SUMMER 2018 STARTS WET....
An unusually strong storm will get summer off to a wet note around much of the central Midwest. Wednesday night 's surface chart depicts a low pressure spinning just SW of Des Moines.
The satellite imagery clearly shows the conveyor belt of moisture that's being drawn into the low pressure center from the Gulf of Mexico.
From there it wraps around the low creating the classic look of a winter storm. While nobody will see any wintry weather temperatures will be dramatically cooler than what we saw Monday. Here's the temperature departures for Thursday. Lots of rain cooledr air wrapping around the storm center.
These are the actual highs the GFS forecasts for Thursday. Upper 50s showing near the Iowa Minnesota border.
The system is well supported at the upper levels as well. The stacked low aloft looks like this at 250 mb Thursday evening.
All of these parameters point to occasional showers and thunderstorms around the central Midwest through at least Thursday night and perhaps part of Friday. With heavy rain falling in many spots the past 2 weeks flooding is a concern...both river and flash flooding. Already moderate flooding is forecast on the Mississippi in coming days. Here's the rains that have fallen the past 2 weeks. Up to 8" in northeast Iowa.
Here's what the 3k NAM if forecasting for total rainfall the next 2 days.
The lower resolution NAM has this.
Needless to say soggy times are ahead but at least it won't be hot. Welcome to the official start of summer. Roll weather...TS