Before I get into the expected tornado outbreak on Monday across the upper Midwest, I wanted to mention that severe weather is likely this afternoon into tonight across southern Oklahoma and north Texas. Slow moving strong to severe thunderstorms are expected across this area, especially right along the Red River. Damaging winds and a couple of tornadoes seems to be the main threat.
The severe weather threat looks to shift into the central Plains states on Sunday and more specifically across central and northwestern Nebraska, southern South Dakota and far northern Kansas. Main severe weather threat looks to be large hail and damaging winds.
Now, turning to Monday’s expected tornado outbreak across the upper Midwest – A strong upper level trough of low pressure will move into the northern Plains states during Monday. This weather system will interact with an unusually moist and unstable air mass for late April across the upper Midwest leading to the potential for a severe weather and tornado outbreak.
Intense, long-lived supercell severe thunderstorms are expected during Monday afternoon across the upper Midwest & looks to be centered across southeastern Minnesota, western Wisconsin and central and northeastern Iowa. These supercell storms will be capable of producing very large hail and strong to violent tornadoes. This tornado outbreak threat area includes Minneapolis-St. Paul, La Crosse and Des Moines.
Finally, turning briefly to the tropics – I am still planning on beginning to issue my regular tropical weather discussions on Thursday, May 1.
Some of the model guidance (GFS model) seems to be hinting at the possibility of some sort of tropical development to the northeast of the Lesser Antilles over the open central Atlantic during the first week of May.
Other model guidance (CFS model) are hinting at the possibility of some sort of low pressure system to affect Puerto Rico, the Virgin Islands and the Leeward Islands during the first week of May. While it doesn’t look tropical or sub-tropical, it could still bring some heavy rain and squally weather to Puerto Rico, the Virgin Islands and the Leeward Islands around May 6 and May 7.
Finally, the European AIFS model is hinting at the possibility of some sort of sub-tropical development near the Georgia and South Carolina coastline around US Southeast Coast around May 10.
One thing to note is that there is no consistency between the models on where tropical or sub-tropical development may be most possible during early May. Because of this, I am skeptical of all of the models & want to see more consistency before I start highlighting an area of concern.
That said, given the possibility that there could be some sort of development chances during early May, I am planning on starting to issue regular tropical weather discussions this coming Thursday, May 1. Should the tropical development chances increase before then, I will start to issue regular tropical weather discussions before Thursday.