May 8 Busiest Day of Severe Weather Season So Far

Fig. 1: NOAA/SPC counts 575 severe storm reports yesterday, the most for any day so far in 2024.

Discussion: Yesterday’s severe weather outbreak across the Midwest States to the Carolinas was the strongest of 2024 so far. Featured were 575 severe weather reports of which 341 were damaging hail, roughly 60% of all reports (Fig. 1). Contributing to the severe weather set-up is an amplified upper trough over the western Great Plains clashing with a subtropical ridge causing record heat across Mexico.  Additional severe storms are likely today centered on the Gulf States and extending to the Mid-Atlantic region (Fig. 2). Once again, a large area of high-risk damaging wind gusts (Fig. 3) and hail (Fig. 4) is expected mostly focused on East Texas still recovering from recent historic flooding rains. The upper trough causing the severe weather drops anchor in the Northeast U.S. into the weekend causing day after day of a chilly rainfall centered on Pennsylvania (Fig. 5). More rainstorms are ahead for next week. Excessive rain and attendant flash flooding is centered on Louisiana to Mississippi early next week (Fig. 6) slowly shifting into the Southeast States into middle of next week (Fig. 7).

Fig. 2-4: NOAA/SPC severe weather outlook for today featuring more damaging wind and hail.

Fig. 5: A weekend rainstorm is indicated for Pennsylvania using the NBM model.

Fig. 6-7: NOAA/WPC projects more extreme rainfall for next week in the Gulf region.

Fig. 8: The U.S. population weight CDD forecast utilizing all models, their consensus, and comparing with 48 hours ago and the 10-year/30-year normal.