Northern Gulf Low Pressure System Development Will Lead To Heavy Rain This Weekend Into Early Next Week Across Central & North Florida, The Florida Panhandle, Southern & Eastern Alabama, Much Of Georgia, Much Of South Carolina & Southern North Carolina: Weather analysis as of late this morning indicated that there is plentiful amounts of moisture streaming northward from the Gulf into southern Louisiana and southwestern Mississippi where a stationary front is located. This is leading to moderate to heavy amounts of rain to occur at the time of this writing across central and southern Louisiana and southwestern Mississippi.
It is expected that a low pressure system will form over the north-central Gulf just to the south of coastal Alabama and the western Florida Panhandle by Saturday morning. This low pressure system is then expected to remain either nearly stationary or just mill around coastal parts of Mississippi, Alabama and the Florida Panhandle as we get into Sunday and Monday.
It should be noted that the environmental conditions will be highly unfavorable for any sort of tropical development due to strong wind shear. Even though tropical development is not expected with this low pressure system, the moisture and energy with this low pressure system will interact with a stationary front & produce heavy rainfall with flooding across a large area from central and north Florida northward into the Carolinas this weekend into early next week.
Heavy rain with the potential for flooding is expected the rest of today through tonight across southeastern Louisiana, southern Mississippi, southern Alabama and the western and central Florida Panhandle.
During Saturday and Saturday night, heavy rain with flooding is expected across central and southern Alabama, central and southern Georgia, all of the Florida Panhandle and parts of north Florida.
As we get into Sunday and Sunday night, very heavy rain with likely flooding is expected across the Florida Panhandle, north Florida, central and southern Georgia.
Maximum rainfall totals of 3 to 5 inches are expected from today through this weekend across southern Alabama, central and southern Georgia, all of the Florida Panhandle and north Florida.
Turning to early next week, multiple rounds of heavy rain is expected from much of the Florida Peninsula northward through eastern and southeastern Georgia, all of South Carolina, all of North Carolina and southern and central Virginia. Flash flooding is likely from this heavy rainfall in the upslope regions of the southern Appalachians of southwestern Virginia, western North Carolina, northwestern South Carolina and northeast Georgia.
Slight Possibility Of Western Caribbean Tropical Development Starting Next Weekend: The latest data seems to be trending towards a decreasing chance of tropical development over the western Caribbean starting next weekend. That said, it is not a zero chance and because of that it is something that I’m still going to keep an eye on.
The GFS model seems to have trended from western Caribbean tropical development towards development occurring in the eastern Pacific by about May 19. That said, the GFS model tries to split off a piece of energy that travels eastward to the Lesser Antilles where it produces an area of low pressure over the far eastern Caribbean next Sunday. This low pressure system produces several days of heavy rain across the Lesser Antilles from next Friday May 16 to Tuesday May 20.
The Canadian and European models forecast no tropical development at all next weekend anywhere in the Caribbean.
It should be noted that the European ensemble model guidance still shows a 30 percent chance of tropical development in the far southwestern Caribbean late next week and next weekend. Also, the longer range European ensemble model guidance keeps the chances for tropical development in the 20-40 percent range through the week of May 26 and the week of June 2 across the southwestern Caribbean. So this part of the Caribbean certainly will need to be watched during the second half of this month.
Here Are My Thoughts: While the western Caribbean may need to be watched for possible tropical development during the second half of this month, I do think that the chances of tropical development are lower as compared to what I thought on Tuesday.
An upward motion pulse of the Madden Julian Oscillation is expected to cross the Caribbean during next week. Latest guidance has trended weaker with this upward motion pulse & this is probably why the guidance have trended lower with development chances. It should be noted that the model guidance are showing the next upward motion pulse of the Madden Julian Oscillation to push through the Caribbean and the Atlantic between June 6 and June 16. This could be the next window to watch for possible tropical development.
My thinking as of today is that I’m lowering the chances of tropical development in the western Caribbean to 10 percent starting next weekend. While it is something to keep an eye on, it seems that it’s much more likely tropical development will not occur.
The next tropical weather discussion will be issued on Sunday & will mostly cover the heavy rainfall & flooding threat across the Southeastern United States.