Crown Weather
Discussions

Hurricane Imelda: We are seeing a true Atlantic Fujiwhara interaction occur today between Humberto and Imelda and this is something that you do not see very often. The analysis of both hurricanes show that they seem to be imparting wind shear on each other. With a much weaker Humberto now, it seems that Imelda may end up absorbing part of the circulation of Humberto over the next few days.

Back to Imelda, reconnaissance aircraft have found that the storm has a central barometric pressure of between 980-982 millibars. In addition, peak winds measured by reconnaissance aircraft, are around 75 mph. Because of this, Imelda is now a hurricane.

Imelda is now heading towards the northeast and it is expected that this northeast to east-northeast track will continue for the next few days. It is expected that the relative wind shear over Imelda will fall to very low levels by tomorrow as the hurricane will be moving in the same direction as the upper level winds. Because of this, fairly quick strengthening of Imelda is likely & because of this, the hurricane may be about a Category 2 strength when it passes right over Bermuda on Wednesday night.

Forecast Impacts For Bermuda: A direct hurricane impact from Imelda is expected on the island of Bermuda on Wednesday night as it appears quite possible that the eye of the hurricane will pass right over the island.

This means that tropical storm conditions will develop on Bermuda during Wednesday afternoon. Hurricane conditions with wind gusts of over 100 mph can be expected during Wednesday night with these conditions persisting into part of Thursday morning. Weather conditions will then rapidly improve by late Thursday.

Model Track Forecast:

Satellite Imagery:

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Locally Heavy Rain Possible Along The Northern Gulf Coast During This Weekend: Things “might” get a little interesting over the northern Gulf this weekend as some energy from the two hurricanes break off and rotate westward into the Gulf by later this week. This piece of energy is then expected to push northward reaching the northern Gulf during this weekend & is likely to produce locally heavy rain across much of the northern Gulf Coast throughout this weekend.

One thing to note is that there are a few ensemble members of both the GFS model and the European model that do show a low pressure system forming over the northern Gulf at some point this weekend. At this point though, the ensemble guidance only show a 10 percent chance of tropical development, probably due to the presence of lots of dry air in the western Gulf, which could inhibit any sort of development of any low pressure system that forms.

Either way though, rain seems likely to occur this weekend across immediate coastal areas of southeastern Louisiana, southern Mississippi, southern Alabama and the Florida Panhandle. While it seems possible that a majority of heavy rain may stay offshore, 1 to 4 inches of rain is a possibility across these areas this weekend.

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Could There Be Tropical Development Over The Eastern & Central Tropical Atlantic Next Week?: Some of the deterministic and ensemble members of the GFS, European and Google Deep Mind AI models are showing the possibility of a tropical wave that looks to push off of the coast of Africa on Friday to develop as it heads westward across the eastern and central tropical Atlantic next week.

At this point, there are a few members of both the GFS and European ensemble model that show this possible development. Most members that do show development forecast it to reach the area near the northern Leeward Islands around next Thursday and next Friday. It should be pointed out that the European ensemble model guidance does show about a 30 percent chance of tropical development next week over the eastern and central Tropical Atlantic.

For now, this is just something to keep an eye on, but at this point, I don’t think that it’s anything to be overly concerned or worried about if you are in the Leeward Islands or the northeastern Caribbean.

The next tropical weather discussion will be issued on Wednesday.

Tropical Storm Imelda: Imelda seems to be gradually becoming better organized today with satellite imagery showing deep convection occurring very near the center of circulation, which is located right over Abaco Island in the northwestern Bahamas. Additionally, reconnaissance aircraft investigation Imelda have found that the central barometric pressure has fallen to 994 millibars with maximum winds in the 45-50 mph range.

Imelda is moving slowly towards the north & it is expected that this northward track will continue throughout the rest of today and tonight. During Tuesday, Hurricane Humberto, which is located to the east of Imelda, is expected to break down the high pressure ridge causing Imelda to turn abruptly to the east-northeast. This east-northeasterly track is then expected to continue through the middle and later parts of this week.

This means that it is all but guaranteed that Imelda will stay well offshore of the US Southeast Coast. This also means that Imelda is now expected to directly impact the island of Bermuda as a Category 1 or 2 hurricane on Wednesday night into Thursday morning.

Forecast Impacts:
For The Northwestern Bahamas: Squally weather with occasional wind gusts of up to tropical storm force are expected across the northwestern Bahamas throughout the rest of today. Conditions will then improve as we get into Tuesday.

For Florida’s East Coast: The circulation on the western side of Imelda is likely to continue to produce gusty northerly winds throughout the day today along Florida’s East Coast from about Daytona Beach southward through Vero Beach and Stuart. These winds will diminish as we get into tonight and especially on Tuesday.

Coastal Parts Of South Carolina & North Carolina: Some additional rain, which will be locally heavy at times, is expected across coastal parts of South Carolina and southeastern North Carolina throughout today, tonight and Tuesday. Additional rainfall amounts of up to one more inch can be expected in some areas. Weather conditions are likely to improve as we get into Tuesday night and especially Wednesday.

Bermuda: A direct hurricane impact from Imelda is expected on the island of Bermuda on Wednesday night as it appears quite possible that the eye of the hurricane will pass right over the island. This means that tropical storm conditions will develop on Bermuda during Wednesday afternoon. Hurricane conditions with wind gusts of about 100 mph look likely on Wednesday night into Thursday morning. Weather conditions then will rapidly improve by late Thursday and especially Friday.

It should be noted that this is in addition to the tropical storm conditions that are expected on Bermuda from the outer bands from Humberto. These tropical storm conditions are expected during tonight and Tuesday.

Model Track Forecast:

Satellite Imagery:

The next tropical weather discussion will be issued on Tuesday.

Tropical Depression #9 (Future Imelda): It is looking much more likely today that Future Imelda will turn sharply to the east as we get into Monday and Tuesday and thus head away from the Southeastern United States. This is, obviously, great news for the Carolinas as the impacts from the storm will be much, much less than what was anticipated even a day or two ago.

TD 9 is still disorganized with the center of circulation located just south of Andros Island in the Bahamas & convection extending northward from there towards the Carolinas. To the east of TD 9 is Category 4 Hurricane Humberto, which is expected to close the distance from TD 9 over the next 24 hours and become a big influence on where the depression will track throughout this coming week. It should be noted that Humberto peaked at a 160 mph Category 5 hurricane yesterday & the size and strength of Humberto will have quite a huge influence on pulling TD 9 sharply to the east.

There has been a delay in how quickly TD 9 is organizing and this has caused the depression to not move as quickly to the north as what was expected. Because of this, it is missing the window for it to link up with the upper level low pressure system over the Southeastern United States, which would have pulled it inland into the Carolinas.

Instead, what looks to occur is that the upper level low pressure system will weaken by Tuesday and large and powerful Humberto will become the main influence in where TD 9 will track. This should cause TD 9 to turn sharply to the east right off of the northeast Florida or east-central Florida coast as we get into Tuesday and Wednesday. From there, it seems plausible now that Future Imelda will track towards Bermuda & potentially impact the island later this week. This is what a majority of the ensemble members are now showing – a quick movement to the east-northeast towards Bermuda & then out into the open Atlantic.

That said, there are a few ensemble members of the European model that do show TD 9 getting left behind by Humberto & languishing just offshore of the Carolina and Mid-Atlantic coastline later this week through next weekend. For now, this is not expected as most indicators seem to point towards a quick exit to the east-northeast. That said, this is something that’ll be watched, just in case.

Forecast Impacts:
As for Florida’s East Coast – Any tropical storm force sustained winds will very likely stay well offshore of the east coast of Florida as TD 9 (Future Imelda) tracks to northwest and parallels Florida’s East Coast over the next couple of days. Instead, I think that we’ll see occasional heavy showers that’ll affect the immediate coast of the Treasure Coast and Space Coast of Florida mostly during the day on Monday. Some of these showers may produce wind gusts of up to 40 mph in squalls. Overall, not a big deal at all. These squally conditions will quickly come to an end by Tuesday morning.

As for the Carolinas – Even though TD 9 is now expected to remain far to the south of the Carolinas, heavy rain still looks to be a threat as the moisture from TD 9 interacts with a stationary front in the area.

This means that rainfall totals of 2 to 5 inches can be expected along the immediate South Carolina coast as well as along the immediate coast of southeastern North Carolina from today through Wednesday. This rain will lead to scattered areas of flash flooding. In addition, gusty winds in squalls, rough surf and beach erosion can be expected along the entire coasts of South Carolina and North Carolina over the next 2-3 days.

For Bermuda – Direct impacts from Future Imelda are a possibility late this coming week should this system head directly to the east-northeast. This means that heavy rain, tropical storm to hurricane force winds and extremely rough seas are a distinct possibility around Thursday and Friday. It’s definitely something to watch closely, if you are on the island of Bermuda.

Imelda’s rich plume of tropical air will collide with a stalled front along the coastal Carolinas Monday and Tuesday, bringing the threat of several days of heavy rainfall and scattered flash flooding ahead of the storm along the coastal plains of the Carolinas from Charleston, South Carolina, to Wilmington and Morehead City in North Carolina. Rainfall totals should generally stay in the 3- to 5-inch range for these areas.

Model Track Forecast:

Satellite Imagery:

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Looking Beyond Humberto & TD 9 (Imelda): Unfortunately, we are still not done with the hurricane once Humberto and Imelda exit stage right late this coming week. In fact, I still think that we’re going to be tracking tropical systems through the month of October and very probably well into November.

The latest European weekly models is pointing to the possibility of a brief break in activity during the week of October 6.

Beyond this, the European weekly models seem to suggest activity will pick up big time starting during the week of October 13 in the area that includes the Gulf, the northwestern Caribbean and the southwestern North Atlantic. This includes the Yucatan, Cuba, the north-central and northeast Gulf Coast, Florida & the Southeastern US coast, the Bahamas and Bermuda. This very active tropical activity may then continue through the week of October 20.

In fact, the European weekly model is forecasting 140 percent of normal activity during the week of October 13 and 160 percent of normal activity during the week of October 20.

So, unfortunately, I think that we’re looking at yet another year with a lot of tropical storm and hurricane season late in the hurricane season.

This is something that I will be keeping a close eye on and will have updates as needed.

The next tropical weather discussion will be issued on Monday.

Tropical Depression #9 (Future Imelda): Satellite imagery, weather analysis and reports from reconnaissance aircraft indicate that now Tropical Depression #9 is becoming better organized today with clusters of thunderstorm activity occurring from the southeastern Bahamas southward through eastern Cuba to far western Haiti. Additionally, reconnaissance aircraft have found a low-level center with this system just north of the northeastern coast of Cuba and because of this, it is now a depression. I expect that TD 9 will likely strengthen into a tropical storm as soon as later tonight or during Sunday.

The forecast of TD 9 continues to be a very difficult one as there are no less than 4 weather features influencing the track and strength of this system. These weather features include (1) A weak upper level low pressure system located over the Florida Straits, which seems to be guiding the depression to the north right now; (2) An upper level low pressure system that’s located over the southeastern United States, which should help guide TD 9 northward as we get into Sunday; (3) A high pressure ridge, that’s located near Bermuda, which is expected to slide to the east and weaken, allowing for a possible “escape route” for TD 9 & (4) Almost Category 5 Hurricane Humberto that’s located to the east of the depression, which might try to use its strength and size to pull TD 9 away from the US Southeast Coast causing it to get close to the coast of South Carolina, but not make landfall.

The forecast track of TD 9 throughout the weekend looks fairly straight forward as it’ll be guided towards the north-northwest by the high pressure ridge near Bermuda & the upper level low pressure system over the southeastern United States. This means that this system will head from southeast to northwest through the Bahamas over the weekend & then parallel Florida’s East Coast during Monday. That said, it is expected that this system should remain about 100 miles or so to the east of Florida’s East Coast & because of this, significant rain and wind impacts are not expected across the Florida Peninsula. Instead, expect some occasional showers across the Florida Peninsula with wind gusts of up to 40 mph at times along Florida’s East Coast from Monday through Tuesday, especially from Melbourne to Jacksonville.

As we get into Monday night and Tuesday, the forecast of TD 9 becomes A LOT more complicated and uncertain. What is expected to happen is that the upper level low pressure system over the Southeastern US will be trying to pull future Imelda northwestward towards the Carolinas. At the same time this is occurring, Hurricane Humberto will be trying to capture the depression and pull it eastward. You can see this push and pull between these two weather features on the depression in the latest model guidance.

There has been a notable shift eastward in all of the model guidance’s track of TD 9. It seems that the model guidance are sensing that Category 4 Hurricane Humberto is exerting a bigger influence on TD 9 than what was previously thought. Also, the upper level low pressure system over the Southeastern United States could end up being weaker leading it to exert less influence on the track of the depression. This has led to most of the models to now forecast the depression to slow way down in forward speed just barely offshore of the Carolinas and then turn abruptly to the east leading it to get close, but not make landfall.

The 12Z hurricane track models all seem to suggest a quick yank to the east on Tuesday before TD 9 reaches the Carolinas.

Last night’s Canadian model initially shows a track that yanks the depression away from the Carolinas. It should be noted that the Canadian model does forecast Humberto not fully capturing TD 9 leading to the depression to turn back to the north and ultimately making it as far north as Southern New England next weekend.

The European ensemble model guidance members show that there are up to 40 percent of their members that indicate a stall just barely offshore of the Carolinas followed by a turn back towards the west later next week

The 06Z run of the European AI model shows a lot of meandering just offshore of the Carolinas during next week followed by this system making landfall in the Outer Banks and heading up the Chesapeake.

The most recent run (12Z) of the GFS model seems to have trended towards future Imelda tracking closer to Florida’s East Coast on Monday. These model trends will definitely need to be watched as this trend westward by the GFS model would put heavier squalls into the Treasure Coast, the Space Coast and parts of the First Coast of Florida during Monday. Beyond this, the 12Z run of the GFS model shows TD 9 being yanked to the east just offshore of the South Carolina coast by Wednesday.

Here Are My Thoughts About TD 9’s Track Towards The Carolinas: It cannot be emphasized enough of how complicated and uncertain the forecast still is for TD 9 as it tracks towards the Carolinas as we get into Tuesday and Wednesday.

That upper level low pressure system over the Southeastern United States looks to try to pull TD 9 northwestward towards the Carolinas, but it appears that Humberto’s strength and size may be large enough to pull it to the east instead.

What, to me, looks to possibly occur is that future Imelda will slow way down in forward speed just barely offshore of the South Carolina coast during Tuesday into Wednesday. My thinking is that the center of TD 9 may end up tracking as close as about 100 miles or so offshore of the South Carolina coast during Tuesday and Tuesday night. As we get into Wednesday though, Humberto may partially capture TD 9 and pull it eastward increasing the distance it is from the Carolinas.

Ultimately though, it is possible that Humberto may end up leaving TD 9 behind around late next week leading to even more uncertainty as to where it could end up tracking – whether it be back westward towards the Carolinas or a turn to the northwest and north leading it to head for the Mid Atlantic or New England.

I do think that the depression will get close enough so that there will be heavy rain and gusty winds along the Georgia, South Carolina and North Carolina coasts starting on Tuesday and continuing through Wednesday and perhaps into Thursday. Additionally, some coastal flooding is also possible depending on how close the center of TD 9 gets to the coast.

Even though it is looking increasingly more likely that TD 9 will stay offshore, flooding from rainfall is still a very real threat across eastern North Carolina and eastern South Carolina throughout the first half of next week. Rainfall totals could end up being in the neighborhood of 3 to 7 inches across much of eastern South Carolina and southeastern and eastern North Carolina during next week.

Bottom Line Is That Everyone along Florida’s East Coast, as well as across southeastern Georgia, eastern South Carolina and eastern North Carolina should pay very close attention to the updates of TD 9/Imelda. My biggest concern with TD 9 is the potential for rainfall produced flash flooding in the coastal Carolinas next week & you should be concerned too, if you live in these areas.

I’ve spent so much time trying to figure out TD 9/Imelda that I’m not going to cover Hurricane Humberto. Just know that Humberto should still pass far enough west of Bermuda to not bring hurricane conditions to the island. It looks quite possible though that Humberto could bring tropical storm conditions to Bermuda during the day on Tuesday.

Model Track Forecast:

Satellite Imagery:

The next tropical weather discussion will be issued on Sunday.

Invest 94-L (Future Imelda): First things first, it continues to look like that Invest 94-L (future Imelda) is going to be a definite threat and very possibly directly impact some part of the Carolinas early next week. That said, areas, including northeast Florida, coastal Georgia and eastern and southeastern Virginia need to watch the progress of Invest 94-L extremely closely as impacts in these areas are quite possible. Also, there continues to be a huge amount of uncertainty as to the exact track of this system & whether it’ll barrel inland or stall and then sit and spin very near the Carolina coastline next week. Needless to say, Invest 94-L is a system that needs to be watched extremely closely.

Satellite imagery and weather analysis indicates that the convection around Invest 94-L seems to be gradually organizing. In addition, it appears that a low pressure system has formed somewhere between the southeast coast of Cuba and the Turks and Caicos Islands.

Analysis of the environmental conditions around Invest 94-L reveals that there is a bit less wind shear over this system as compared to yesterday. Also, it appears that Invest 94-L will be heading into lower wind shear conditions and more favorable conditions for development during this weekend. This means that it is extremely likely that Invest 94-L will become Tropical Storm Imelda within the next couple of days or so.

In addition, it is expected that Invest 94-L will move from southeast to northwest through the southeastern and central Bahamas through Saturday and then track across the northwestern Bahamas during Sunday.

By Monday, the uncertainty of where Invest 94-L will go once it is north of the Bahamas is extremely high. The model guidance diverge quite a bit in their forecasts of where this system might go.

The GFS model and a majority of its ensemble members show a track that takes Invest 94-L directly inland into South Carolina and far southeastern North Carolina around Monday night and Tuesday.

The most recent European model run also now shows Invest 94-L moving directly inland into South Carolina on Monday night and Tuesday. As for the ensemble members of the European model, a majority of them show a track that takes this system directly inland somewhere between Hilton Head and Myrtle Beach with a few members showing a landfall as far northeast as southeastern and eastern North Carolina.

As for the Google Deep Mind AI ensemble model, they are split right down the middle. Half of the members showing a direct inland track right into South Carolina. The other half of ensemble members show Invest 94-L getting turned abruptly to the east as it approaches the coast of the Carolinas due to its interaction with Humberto leading to Invest 94-L to not make landfall at all.

Here Are My Thoughts: While I do think that it is looking fairly likely that Invest 94-L will directly impact somewhere between Savannah, Georgia and Wilmington, North Carolina, the uncertainty with the exact track and strength of this system is very high.

It cannot be emphasized enough how complicated the weather pattern is going to be during this weekend into next week and this will certainly affect where Invest 94-L goes.

The first player in the weather pattern is Hurricane Humberto, which is located to the east of Invest 94-L. The closer Humberto and Invest 94-L are in distance, the more they will affect each other with track and strength.

The second player in the weather pattern is an upper level low pressure system over the southeastern United States. If Humberto does not alter the track of Invest 94-L, then it looks plausible that this upper level low pressure system will be able to pull Invest 94-L directly into the southeastern United States.

I think that there are at least a couple of scenarios that could occur with Invest 94-L:

Scenario Number 1 is that Imelda tracks fairly quickly to the northwest from the northern Bahamas on Sunday to the South Carolina coast by Monday night into Tuesday as that upper-level low pressure system captures Invest 94-L and pulls it inland.

This first scenario would lead to hurricane force winds and surge issues along the South Carolina coastline from Monday into Tuesday. In addition, we would be looking at a flooding rainfall across much of the Carolinas and the Piedmont during at least the first half of next week.

Scenario Number 2 is that Invest 94-L (Future Imelda) moves a bit slower in forward speed and is influenced more by Hurricane Humberto as that upper level low moves out of the way to the northeast. This leads to Invest 94-L to approach the Carolina coast, but then stalls just offshore being pulled to the east away from the coastline. This would make for an extraordinarily difficult forecast as it opens up multiple different other scenarios. This includes Humberto pulling Invest 94-L with it out into the open Atlantic. It also includes Humberto departing to the northeast and leaving Invest 94-L behind causing it to track again towards the coast for a second attempt at a landfall late next week.

It Is Of My Opinion that I think scenario number 1 may be more likely to occur than scenario number 2. This means that I think that it is likely Invest 94-L will become a depression within the next 24-30 hours or so as it tracks through the southeastern and central Bahamas. This system should then strengthen into a tropical storm and then a hurricane as it approaches the Carolinas on Monday and crosses the Gulf Stream as it does so.

I do think the area of highest threat right now of a landfall and direct hit from this system looks to be along the South Carolina coast on Monday night or Tuesday as a hurricane of perhaps Category 1 or low end Category 2 strength.

Now, is this a guaranteed forecast?? Absolutely not!! There are a lot of moving parts with the forecast of this system, including how quickly Humberto strengthens, Humberto’s forward speed, how strong the upper level high pressure system is & the evolution of the upper-level low pressure system over the Southeast United States.

It seems clear though that Invest 94-L is very likely to develop & become a tropical storm and then a hurricane. It also seems fairly likely now that Invest 94-L is a threat to the Southeastern coast of the US & especially the Carolinas.

In addition to the potential for impacts from tropical storm to hurricane force winds and surge issues along the South Carolina coast, I am also quite concerned about the potential for heavy rain and flood issues across the Lowcountry of South Carolina into central and eastern North Carolina and southern Virginia. In fact, it looks like the setup is favorable for a Predecessor Rain Event to occur out ahead of future Imelda this weekend across southern Virginia, central and especially eastern North Carolina and across the Lowcountry of South Carolina.

Now, we may end up adding in the heavy rainfall from Invest 94-L (future Imelda) into the mix and this could lead to some big time flood issues across southern Virginia, a large part of North Carolina and eastern and northeastern South Carolina. What concerns me is that there’s the possibility that future Imelda could slow way down or stall near the coastal Carolinas on Monday and Tuesday and exacerbate the rainfall issues.

Over the next day or two, I should be able to tell you in more detail exactly which parts of the Carolinas will see the most impactful conditions. I strongly urge everyone from southeastern Georgia through the Carolinas to southern Virginia to closely monitor the updates of this system. If it were me, I would start preparing now for tropical storm and hurricane conditions along the coast & for the potential of serious rainfall produced flash flooding for areas along the coast and areas inland across the Carolinas and southern Virginia.

Model Track Forecast:

Satellite Imagery:

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Hurricane Humberto: The discussion on Humberto will be a very short one again, as most of my attention is on Invest 94-L (future Imelda).

Humberto is undergoing rapid strengthening today and it looks quite likely that it will be a major hurricane as soon as tonight. Humberto looks to probably peak at Category 4 strength as it begins to turn to the northwest and shoot the gap between the Bahamas and Bermuda this weekend.

As we get into the first half of next week, Humberto looks to curve to the north and northeast around the western side of a high pressure ridge over the central North Atlantic. Because of this, it still looks likely that Humberto will remain east of the Bahamas and the East Coast of the United States.

As for Bermuda, it looks as if Humberto will track far enough to the west of the island around Tuesday and Wednesday to not directly impact Bermuda. That being said, some impacts to Bermuda are possible, especially in terms of rough surf and some of the outer rain bands affecting the island during the first half of next week.

Model Track Forecast:

Satellite Imagery:

The next tropical weather discussion will be issued on Saturday.

Invest 94-L (Future Imelda): First things first, I do think that Invest 94-L (future Imelda) is a potential very real threat to areas from northeast Florida and coastal Georgia through the Carolinas and into southeastern Virginia sometime early next week. That being said, there is still a ton of uncertainty as to how strong this system will become and where it will ultimately track. Invest 94-L is definitely a system that needs to be watched extremely closely.

Satellite imagery and weather analysis reveals that Invest 94-L is still disorganized with most of the thunderstorms being blown to the south by northerly wind shear. Any center that is trying to form seems to be located of any center that might be trying to form. The actual center looks to be located near the north coast of of the Dominican Republic with most of the convection occurring just to the south of the Dominican Republic.

It is anticipated that Invest 94-L will move into the southeastern Bahamas by Friday and then push into the central and northern Bahamas during Saturday and Saturday night. The environmental conditions look more favorable for Invest 94-L to develop in the Bahamas and because of this, I do think that we’ll see it become a depression sometime this weekend as it pushes northwestward through the Bahamas.

A look at the latest model guidance reveals that there has been a trend over the last 24 hours for Humberto, which is located to the east of Invest 94-L, to move slower & for Invest 94-L to move quicker in forward speed. This has led to a forecast increased distance between these two systems leading to them having less influence on each other. The reason for these changes in the model guidance is due to a trend towards a stronger upper level high pressure system over Humberto leading it to strengthen quicker & move slower in forward speed.

This increased separation between these two systems gives Invest 94-L (future Imelda) more of an opportunity to strengthen without being affected by Humberto. It also leads to Invest 94-L to potentially be influenced more by the upper level low pressure system over the Southeastern United States. The consequence is for Invest 94-L to be pulled right into the Southeastern coast of the United States between northeast Florida and southeastern Virginia early next week rather than be booted away from the coast and out into the open Atlantic.

Both the most recent GFS ensemble and European ensemble model guidance have a large number of members that show a track that takes Invest 94-L right into eastern South Carolina and eastern North Carolina sometime between Monday and Wednesday of next week. That said, there are some members of both ensembles that show a track towards coastal Georgia and coastal South Carolina while other members still do show a track that still keeps it just offshore of the Southeast coast of the US.

The Google Deep Mind AI ensemble model members are split with some showing a landfall somewhere between northeast Florida and coastal South Carolina around Monday or Tuesday & other members that show a sharp turn to the northeast and has this system going out into the open Atlantic.

All-in-all though, the model guidance have definitely trended towards a higher threat to the Southeast coast of the United States during the early part of next week.

Here Are My Thoughts: As I have mentioned a few times already, I do think that the odds of Invest 94-L directly impacting some part of the Southeast coast of the US are increasing & everyone from northeast Florida through the Carolinas to southeastern and eastern Virginia need to watch this system extremely closely.

In looking at all of the data today, my take is that I think that this system will become a depression by this weekend in the Bahamas and then strengthen into a tropical storm shortly after that. From there, additional strengthening into a hurricane looks quite plausible especially when its approaching the coastline on Monday & crosses the Gulf Stream.

I do think the area of highest threat right now of a landfall and direct hit from this system looks to be along the South Carolina coast into southeastern North Carolina late Monday or early Tuesday as a hurricane of perhaps Category 1 or Category 2 strength.

Now, is this a guaranteed forecast?? Absolutely not!! There are a lot of moving parts with the forecast of this system, including how quickly Humberto strengthens, Humberto’s forward speed, how strong the upper level high pressure system is & the evolution of the upper-level low pressure system over the Southeast United States.

It seems clear though that Invest 94-L is very likely to develop & become a tropical storm and then a hurricane. It also seems as if this system is a threat to the Southeastern coast of the US & especially the Carolinas.

Model Track Forecast:

Satellite Imagery:

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Tropical Storm Humberto: My discussion on Humberto will be shorter than the one for Invest 94-L.

Humberto seems to be strengthening today and this strengthening is likely to continue. Because of this, it is expected to become a hurricane by late Friday or early Saturday.

It is expected that Humberto will remain to the east of the Bahamas and the East Coast of the United States and not be a second threat to these areas.

As for Bermuda, the model guidance seems to have trended further west with the forecast track of Humberto. If these trends hold, then Humberto may end up passing to the west of the island around Tuesday and Wednesday of next week. That being said, some impacts to Bermuda are possible, especially in terms of rough surf and some of the outer rain bands affecting the island during the first half of next week.

That being said, it’s still too soon to say that Bermuda is completely out of the woods in terms of a more direct impact from Humberto. I urge those of you on the island of Bermuda to closely watch the forecasts of Humberto very closely as it’s possible it could be a strong hurricane by the time it reaches the latitude of Bermuda.

Model Track Forecast:

Satellite Imagery:

The next tropical weather discussion will be issued on Friday.

Two robust tropical disturbances, Invest 93-L (the easternmost disturbance) and Invest 94-L (the westernmost disturbance, are likely to develop into tropical storms and possibly hurricanes over the next few days & could very well become viable threats. The westernmost disturbance, Invest 94-L, is likely to track through the Bahamas & then be a very real threat to areas from Florida through the Carolinas to the Mid-Atlantic coast early next week. The easternmost disturbance, Invest 93-L, could end up being a threat to Bermuda early next week.

It needs to be emphasized that the overall forecast of both Invest 93-L and Invest 94-L is extremely uncertain as both systems will influence each other in both track and strength. In fact, these two disturbances could end up rotating around each other in what’s called the Fujiwhara effect.

Invest 94-L: First, to discuss the westernmost disturbance, Invest 94-L, which is located over the northeastern Caribbean.

Satellite imagery today reveals that the convection around Invest 94-L is disorganized & there seems to be 20-40 knots of west-northwesterly wind shear affecting it. Because of this, development is not expected for at least the next couple of days.

Beyond this, the forecast track and strength of Invest 94-L becomes highly uncertain once it reaches the Bahamas by early this weekend as it will be heavily affected by Invest 93-L.

My thinking is that Invest 94-L should track into the area around the Bahamas by this weekend. An upper level low pressure system over the Southeastern United States will produce a south to north upper level wind flow causing Invest 94-L to turn to the north by about Sunday and Monday. This is when the influence of Invest 93-L will come into play and thus will probably lead to all sorts of forecasting headaches as scenarios run everything from a track right into the Carolinas all the way to being yanked out into the open Atlantic. More on this later in this discussion.

Invest 93-L: Invest 93-L, which is the easternmost disturbance, seems to be organizing today with satellite imagery revealing an elongated area of convection. It seems likely that Invest 93-L will be the first one of the two disturbances to develop and in fact, it could be a depression as soon as later tonight or on Thursday.

With Invest 93-L being the easternmost disturbance, it’ll be a lot harder for it to close in on the East Coast of the United States. Instead, I could see it becoming a very real threat to Bermuda by early next week. That said, it’s possible that Invest 93-L could try to rotate to the north of Invest 94-L and try to track towards the northwest and west-northwest during next week leading it to try to come close to the New England coastline.

Again, the interaction between this disturbance and Invest 94-L is going to make for a very difficult and uncertain forecast.

The Interaction Between Invest 93-L & Invest 94-L Makes For An Extremely Uncertain & Complicated Forecast: Both Invest 93-L and Invest 94-L are expected to track in a westerly direction over the next couple of days. By this weekend, both disturbances will likely turn towards a northerly direction as they are guided on the western side of a high pressure ridge over the central North Atlantic.

The forecast then becomes very complicated as these two systems will get quite close to each other in distance & because of this, they will influence both the track and strength of both disturbances.

It’s actually possible that Invest 93-L and Invest 94-L will be close enough to each other next week, so that the Fujiwhara effect could occur. What is the Fujiwhara effect? It’s when the two circulations (Invest 93-L and Invest 94-L) become entangled with one another & end up rotating around a common pivot point. This is something that is uncommon in the Atlantic, but it can sometimes happen.

Most of the model guidance seem to want to keep these two systems distinct tropical systems, however, the guidance are not in agreement with each other on which system might be the stronger and more dominant one.

The European model, for example, forecasts that both Invest 93-L and Invest 94-L will be hurricanes by early next week.

The GFS model, on the other hand, show that the westernmost system (Invest 94-L) will be quite weak & Invest 93-L (the easternmost system) will be the one to become a hurricane. In fact, the GFS model forecasts that Invest 93-L will end up absorbing the circulation of Invest 94-L.

The Google Deep Mind AI model looks similar to the European model and shows the potential for two dueling hurricanes that will be close to each other in distance by early next week.

Bottom Line Is That If you live in Bermuda, the Bahamas, or on the East Coast from the Florida Peninsula through the Carolinas and the Mid-Atlantic coastline to Southern New England, keep close tabs on the progress of what is going on with these two systems. I cannot emphasize enough how uncertain the forecast is. When you get two systems like this in-close to each other, some very strange things can happen. Everything from significant land impacts to some part of the East Coast to both systems harmlessly heading out into the open Atlantic are possible.

Finally, the next two names on the list are Humberto and Imelda. I do think that the easternmost disturbance (Invest 93-L) will probably be Humberto and the westernmost disturbance (Invest 94-L) may end up becoming Imelda at some point.

The next tropical weather discussion will be issued on Wednesday.

With Hurricane Gabrielle heading safely out into the open Atlantic, I want to concentrate a lot more on Invest 94-L, which poses a potential threat to the Bahamas & parts of the East Coast of the United States and Invest 93-L, which might pose some threat to Bermuda.

Invest 94-L Located Over The Lesser Antilles: Satellite imagery and weather analysis today indicates that the northerly wind shear that has been affecting this system has caused it to track more to the south than what the guidance indicated even yesterday. Because of this, it looks very likely now that Invest 94-L will continue to track right through the Lesser Antilles during the rest of today before it heads right over Puerto Rico and Hispaniola during Wednesday into Thursday.

This means that those of you in the Windward and Leeward Islands will continue to see occasional squally weather throughout the rest of today into tonight. This squally weather will affect much of the Virgin Islands, Puerto Rico and Hispaniola throughout Wednesday and will probably last into Thursday.

Strong northerly wind shear is expected to continue to affect Invest 94-L over the next 2-3 days or so and because of this, development is not expected anytime too soon. As we get into Friday and Saturday, however, the environmental conditions around this disturbance will become more favorable for development, just as its moving into the southeastern Bahamas.

A look at the latest model guidance reveals that it seems both the conventional models and the AI models now forecast development of Invest 94-L and also forecasts it to get quite close to the East Coast of the United States.

The Google Deep Mind AI model looks quite aggressive in showing Invest 94-L being a threat to not only the Bahamas but also to the Southeast coast of the United States during the early part of next week.

The European AI model also shows Invest 94-L being a threat to the Southeast coast of the United States during the early part of next week.

As for the conventional models, the GFS ensemble model guidance is further offshore than the AI models and most ensemble members show a close brush with the outer banks of North Carolina early next week.

The European ensemble model guidance looks further west than the GFS ensemble guidance with a few members pointing towards a coastal North Carolina impact early next week.

Here Are My Thoughts: As I mentioned yesterday, those of you in the Bahamas and along the US East Coast should keep a close eye on the progress of Invest 94-L as it could be a problem come late this weekend and early next week.

The environmental conditions around Invest 94-L are currently unfavorable for development, but are expected to become favorable when this system moves into the Bahamas this weekend. This means that we could very well have a developing tropical system right in the Bahamas by early this weekend.

The weather pattern during this weekend into early next week looks quite complicated & because of this, the overall track of whatever forms is highly uncertain. There’s the expectation that there will be a cutoff upper level low pressure system in place over the southeastern US with a high pressure ridge located over southeastern Canada. This is a pattern that is actually quite favorable for an East Coast tropical impact. That being said, the influence of the other tropical disturbance, Invest 93-L, located just to the east of Invest 94-L could lead to some high jinx in the forecast.

It’s possible that the interaction between Invest 94-L and Invest 93-L could cause both systems to completely miss the entire East Coast of the US, especially if the disturbance further east (Invest 93-L) gets stronger & has more influence on the overall weather pattern.

It’s equally as possible that the upper level low pressure system is able to capture Invest 94-L and guide it to the north-northwest towards the Southeast coast of the United States or the Mid-Atlantic coastline early next week.

Bottom line is that all interests along the East Coast from the Florida Peninsula to New England should monitor the progress of Invest 94-L. The area that I’m most concerned about in terms of any impacts are along the Carolina and Mid-Atlantic coastlines. That said, there is still A LOT to figure out with this system & how the overall weather pattern will affect it. Also, there’s the question on how Invest 94-L will interact with Invest 93-L. All-in-all, a very uncertain forecast.

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Invest 93-L Located About 1000 Miles To The East Of The Lesser Antilles: Located to the east of Invest 94-L is another tropical disturbance, designated Invest 93-L. This disturbance is located about 1000 miles or so to the east of the Lesser Antilles.

Right now, Invest 93-L seems to be gradually organizing & probably will develop in the coming days. All signs seem to point towards Invest 93-L strengthening into a tropical storm and possibly a hurricane as it curves to the north away from the Caribbean, but towards Bermuda.

While there is potentially a threat to Bermuda early next week from Invest 93-L, it seems as if this system will curve far enough offshore to not be a threat to the Bahamas or the East Coast of the United States.

The next tropical weather discussion will be issued on Wednesday.

Hurricane Gabrielle: Gabrielle is rapidly strengthening today and it is now a major hurricane with 120 mph maximum winds.

Gabrielle is heading towards the north-northwest and it is fully expected that the hurricane will pass safely to the east of Bermuda later today. Beyond this, it is expected that Gabrielle will turn to the northeast and head out into the open Atlantic. In addition, it is expected that Gabrielle will continue to strengthen throughout the rest of today before it begins to weaken due to increasing amounts of wind shear and cooler ocean water temperatures.

Finally, it should be noted that the swells created by Gabrielle will affect Bermuda throughout the next few days. These swells will also affect areas of the US East Coast from the North Carolina coastline northward to the New England coastline over the next couple of days or so. These swells will lead to extremely rough surf and dangerous rip currents.

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Area Of Disturbed Weather Located About 400 Miles To The East Of The Leeward Islands: Satellite imagery today indicates that there is a tropical wave that’s producing disorganized convection located just to the east of the Leeward Islands. This disturbance could be a system to really, really watch closely throughout this week for those of you in the Bahamas & along parts of the US East Coast from the Carolinas and points northward.

Analysis of the environmental conditions around this disturbance reveals that there is 30 knots of northerly wind shear affecting this system. This northerly wind shear is being produced by the outflow from Gabrielle & for now, these strong wind shear values will impede any sort of development. The environmental conditions may become more favorable for this disturbance to develop when it nears the Bahamas later this week.

A look at the model guidance reveals that while most of the models show this system reaching the Bahamas later this week, they have differing solutions on what might occur.

For instance, the GFS model has been pretty consistent in forecasting this system developing into a tropical system that impacts the southeastern Bahamas late this week. The GFS model then forecasts this system will head up the East Coast & directly impact the North Carolina Outer Banks next Monday before passing to the south of New England next Tuesday.

On the other hand, the European model forecasts this disturbance to struggle & not really develop at all. Instead, the European model forecasts that the disturbance that’s located to the east of this disturbance to develop instead.

As for the ensemble model guidance, the GFS ensemble model guidance has quite a few members showing development over or just east of the Bahamas late this week. From there, the GFS ensemble model guidance have many members showing a track just offshore of the US East Coast, but there are a few members that do show a direct impact to the North Carolina coastline & the Mid-Atlantic coast early next week.

The European ensemble model guidance has about 30-40 percent of its members forecasting development in the southeastern and eastern Bahamas on Friday into Saturday. From there, the European ensemble model guidance has most of its members keeping this system offshore of the East Coast of the US. That said, it does show a couple of members hinting at this system stalling just offshore of the Georgia and northeast Florida coast.

As for the Google Deep Mind AI model, a majority of its ensemble members show a developing tropical system in the Bahamas between Friday and Saturday. That said, there are a separate clustering of models that show this system developing in the Florida Straits. The clustering of models that forecast development in the Bahamas show a track northward that threatens areas from the North Carolina coastline northward to Southern New England. The other clustering of models that forecast development near the Florida Straits show a track into the eastern Gulf.

Here Are My Thoughts: I do think that we really need to keep a close eye on this particular disturbance as it could affect the Bahamas at the end of this week & then potentially get very close to some part of the East Coast of the United States.

While the conditions are currently unfavorable for development, these conditions do look a little more favorable for development near the Bahamas. Because of this, we could very well have a developing tropical system right in or very near the Bahamas at the end of this week.

As for the possible steering of this system. The upper level weather pattern near the East Coast of the United States this weekend into next week look to favor this system eventually turning to the north and northeast. The big question is how far west could this system get before it turns.

On one hand, it’s possible that a cutoff upper level low pressure system over the Southeastern United States could yank it quickly to the north and northeast leading it to brush the eastern Bahamas & then barely miss the East Coast of the United States.

On the other hand, it’s possible that this disturbance could be steered further to the west by the other tropical wave located further to the east. Should this occur, it could lead to this disturbance missing being pushed out by that upper level low & then meander near the Bahamas and the Southeast Coast of the United States early next week.

Given how high the uncertainty is with where this system might track & how strong it might get, I would closely keep an eye on it if you are in the Bahamas and anywhere from the Florida Peninsula through the Carolinas to the Mid-Atlantic States.

Finally, this disturbance is expected to bring some squally weather to the Leeward Islands & especially the northern Leeward Islands tonight through the day on Tuesday.

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Area Of Disturbed Weather Located Halfway Between The Lesser Antilles & The West Coast Of Africa: The other disturbance to discuss today is currently located over the central Tropical Atlantic near about 40 West Longitude. This system seems to have a better chance of developing over the next few days as the environmental conditions are favorable. Fortunately, it looks fairly likely that this disturbance will stay to the north of the Lesser Antilles & not be a threat.

Looking beyond this, the model guidance all agree that this disturbance could move into an environment north of the Caribbean that is favorable for development. Because of this, we could have a tropical storm or a hurricane that tracks further west than what Gabrielle is currently tracking. This means that this particular disturbance could eventually become a threat to Bermuda around early next week.

As for the Bahamas and the East Coast of the United States, it currently looks as if an upper level trough over the western North Atlantic should steer this system away from the Bahamas and the US East Coast. That said, given the possible interaction with the other tropical wave, there is some uncertainty as to the final track of this system, but odds are that it should pass well east of the Bahamas and the US East Coast.

The next tropical weather discussion will be issued on Tuesday.

Tropical Storm Gabrielle: Some westerly wind shear is affecting Gabrielle this morning as most of the convection is located just to the east of the low-level center. That said, the convection that is occurring today is quite intense & thus once the wind shear does decrease over Gabrielle, it’ll probably strengthen fairly quickly.

Gabrielle is heading in a northwesterly direction today and this northwesterly movement is expected to continue throughout this weekend. By Monday, it is expected that Gabrielle will turn to the north and northeast and pass well east of Bermuda during the day on Monday. From there, Gabrielle will likely head out into the open Atlantic and not be a threat to anyone.

As I already mentioned, the wind shear values over Gabrielle will likely decrease over the next couple of days and this should allow the storm to undergo some quick strengthening as we get into early next week. This means that Gabrielle will likely become a hurricane as soon as late Sunday and may end up peaking at around Category 2 strength during Monday and Tuesday, just as it’s passing to the east of Bermuda.

Not only does it look likely that Gabrielle will not be a threat to the Bahamas or the United States, but it also looks likely now that Gabrielle will pose no significant threat to Bermuda. That said, Gabrielle may still produce some rough surf and rip currents to Bermuda during the early part of next week.

Model Track Forecast:

Satellite Imagery:

Finally – Quiet conditions are expected throughout the rest of this weekend across the rest of the Atlantic, Caribbean and Gulf. There are no other areas to be concerned about in terms of development.

I’m still keeping a close eye on the area from the western Caribbean to the Bay of Campeche and the southern Gulf for later this month. At this point though, there are no changes at all to what I wrote in yesterday’s update. Those thoughts were that I do think that the area from the western Caribbean through the Bay of Campeche and the southern Gulf will definitely need to be watched closely for possible tropical development during the week of September 29. Nothing concrete or likely at this time, but it is something to keep an eye on.

The next tropical weather discussion will be issued on Monday.