STORM THREAT FOR SOME SUNDAY NIGHT...
I was just looking over some new data and was impressed with the convective potential that's showing Sunday night. A strengthening jet at 5,000 feet along with strong warm air advection will generate stout lapse rates that should set off elevated thunderstorms. Despite the elevated nature of the convection there should be at least 30kts of bulk shear to produce updrafts strong enough to spit out marginally severe hail.
The Storm Prediction Center has put out a marginal risk for strong storms Sunday night over the region highlighted below. The greatest threat is over the SE third of Iowa, WC Illinois, and northern Missouri.
Here's a broader view of the risk area.
In that region the EURO shows some very impressive CAPE (convective available potential energy) of 2400J/kg Sunday night at midnight. That's probably too high but even half that number would be generous instability for the time of night.
You can see the warm air advection I mentioned in the max temperatures the model forecasts Sunday. Highs reach 80 into NW Missouri while mid 50s prevail over EC Iowa. That's the lift or forcing that will trigger the storms Sunday evening.
Dew points also reflect the on going warm air advection as they range from 65 in NW MIssouri to the 30s in EC Iowa Sunday evening.
That's a huge jump in moisture from Saturday when dew points in NW Missouri were in the teens at 3:00pm.
Below you can see the returning instability in the rising heights ahead of the advancing short wave entering the western Plains.
At midnight the GFS surface depiction shows a cold front bisecting Iowa with thunderstorms over the SE half of my local area.
The hi res 4k NAM shows the storms in greater detail
Where storma do develop some local spots could see up to an inch of rain. However, general amounts should be on the order of 1/4" or less. Here's what the 4k NAM has for rainfall.
The GFS shows this.
Once again, most of the showers and storms are not expected until mid-evening or later Sunday night. Thus, Sunday itself should be a decent early spring day over much of the Midwest. Roll weather...TS