ST. LOUIS – Following a deadly tornado Friday in the area, the St. Louis region is expecting more severe weather Monday into Tuesday.
There will be a chance for a small shower or thunderstorm at just about any point the rest of Monday morning into the afternoon, but coverage looks to remain isolated and the duration brief. There will be lots of dry time during the day with a mix of clouds and sunshine.
Much of the day between now and 6 p.m. looks decent to be honest. The rough part of the forecast unfolds late this afternoon well to our west, and then translates east into our viewing area this evening into tonight.
Monday evening and night
From 6 p.m. to 1 a.m. or so, this is the peak time for severe weather potential for our viewing area. Storms will spread into our viewing area from the west and southwest.
All severe hazards are possible with these storms with the greatest risk setting up over central Missouri. That’s where a Level 3 (out of 5) risk exists through about midnight. Further east into the St. Louis Metro area, the risk level drops a notch to a Level 2 (out of 5) as instability becomes a bit more questionable.
The max hail size is closer to quarters and golf balls and the max wind speeds are closer to the baseline 60 mph range. While there is some potential for a tornado tied to an advancing warm front, this set-up would seem to favor the lower end of the tornado spectrum in our viewing area.
The severe threat will be highest in eastern Missouri/the St. Louis area from 8 p.m. to 1 a.m. After 1 a.m., the instability really wanes and the severity of the storms should come down quite a bit.
Unfortunately, pockets of non-severe storms will remain possible and that could lead to localized high water issues in flood prone areas. So we do need to keep an eye out for that—that threat is pretty much area-wide. The bulk of the overnight rain will be well east of STL by 5 a.m.
Tuesday
There remains uncertainty about the coverage and potential of any redevelopment for Tuesday afternoon.
It will be largely dictated by the ability of the atmosphere to recharge after Monday night’s storms. There is a chance the atmosphere will be scrubbed of the instability Tuesday with the main focus for new severe storms focused to our east and south.
However, that is not certain at this point and a Level 2 risk remains posted for far eastern Missouri into southern Illinois for the possibility of redevelopment Tuesday from midday through mid-afternoon. I could see that dropping if the atmosphere really gets scrubbed out tonight.
But, if that doesn’t happen, tomorrow could get a little frisky again…especially from St. Louis to the east into southern Illinois. We’ll have to wait and see.