Spring Starts Warmer, Cloudier
That was a good week and a half of winter. Spring begins Monday.
South winds will move high temps into the mid 70°s.
We’ve taken the chance of rain out of the forecast for Monday afternoon, although expect clouds and don’t be shocked if you see a sprinkle.
You may see a passing shower Monday night, which I doubt.
Tuesday Morning Rain, Evening/Late Night Storms
The NAM3 model shows light, off-and-0n showers moving through Tuesday from 1AM to 2 PM:
This may be enough to cause a rainout for Tuesday night’s activities.
Hard to say now, but we may see a break in the rain Tuesday afternoon.
More rain and storms are on the way Tuesday night.
The storm setup for Tuesday night has prompted the Storm Prediction Center to outlook our severe weather potential as a 1 on the scale of 0 to 5:
Observe all uncertainties.
Global models expect an evening/late night event, in the form of a group of storms located along the Kentucky/Tennessee border, moving our way kinda along I-24.
The NAM3 model is now in range. Notice it groups storms around the TN/KY border around 8 PM, and keeps them coming in waves well after midnight.
It’s possible these may pass to our east.
Tornadoes? Probably not. The GFS model is showing a low-end tornado environment Tuesday night, with plenty of moisture (dew point 63°). instability (CAPEs around 1,000 j/kg), low cloud bases (LCLs under 200m), but not very much shear (bulk shear is 45 kn). The shear is “speed shear,” meaning the winds are only going faster the further up you go, but they really aren’t turning all that much. Most of the forecast soundings we see show “elevated” thunderstorms, which are the opposite of the “surface based” storms which contain the higher tornado risk.
We aren’t ruling tornadoes out, but right now there is no reason to worry. We will need to watch it as the models resolve themselves. I am sure the models do not have it “exactly right.” Storm type forecasts like this are always full of uncertainty.
Damaging straight-line winds are the primary storm threat.
Hail is also possible. In the heavier storms, there should be enough shear aloft to support hail. This is less likely than the wind threat.
Lightning? Likely, yes.
Rainout Alert? Yes. Our NWS thinks we will see 0.14″ of rain by 7 AM Tuesday, and another 0.36″ by 7 PM Tuesday night. Add another 0.25″ beginning at 7 PM Saturday. Expect practices and games Tuesday night to be rained out.
Dry Rest of the Week: Saturday Storms?
Tuesday’s storms will be riding a cold front, which will have passed by noon Wednesday, taking the temp down to the mid 40°s Wednesday morning and not quite to 60° Wednesday afternoon. Expect to stay dry from Wednesday afternoon through Friday around noon.
There’s been a lot of interest in a weekend storm system. Models continue to vary. Certainty is low. To quote today’s forecast discussion from the Storm Prediction Center: “Uncertainty is substantial at this range in the forecast period.”
This is what has our attention for Saturday.
That “L” is in the right place for severe weather….however, rather than moving northeast along the Ohio River and raising alarm, the latest run of the GFS thinks the “L” rather drunkenly wanders around west Tennessee. That would make this a rain event Saturday.
Other models, and other runs inside those models, continue to spit out very different solutions.
So I’d say rain looks more likely Saturday after noon and into the evening, but as for storms, we just don’t know.