When you see a five day rainfall forecast that looks like the one below, you can bet the farm that the area coated in yellow, orange, and red is situated in what's known as the "baroclinic zone". Essentially that's the area where the fight is on between warm moist air to the south and significantly cooler and drier air to the north. It's the battleground for heavy rain, thunderstorms, and in some cases...severe weather.
The contrast associated with the "baroclinic boundary" shows up nicely in the forecast temperature departures Friday.
Actual readings at 7:00 am range from the upper 30s in North Dakota to the upper 60s in NE Kansas.
The warm sector has the ability to hold far more moisture which is evidenced in the water vapor forecasts, PWAT values (precipitable water) are as high as 2.00" in Missouri and as low as 0.35: in North Dakota.
Where the greatest instability resides, (those areas where the warmth and moisture are highest), is where the severe weather threat is maximized. The Storm Prediction Center has issued these convective outlooks for severe storms Wednesday and Thursday.
For the most part the best instability remains just to the south of my area. That said, it's possible a few elevated storms could produce some marginal hail or gusty winds over SE Iowa or WC Illinois. The bigger threat will be locally heavy rains around my area, The Euro indicates widespread 1-3" totals through Sunday.
As far as timing the rain, the first batch arrives late Wednesday afternoon or night and lingers into much of Thursday. That's followed by a break but more rain returns for Saturday and Saturday night.
After another cool day Wednesday, temperatures look more seasonal Thursday through the weekend (highs 67-72). Beyond that we're still on track for a summery surge next week. Highs should be be near 75 Tuesday and 80s are likely Wednesday and Thursday. Below you can see the Euro meteogram for Cedar Rapids.
While there are some rough spots the next few days, what's to come next week is worth the wait. Patience is a virtue,,,or so they say! Roll weather...TS