COOL LOOKING TO RULE INTO FALL...
Late Wednesday afternoon at the Swails ranch in Cedar Rapids was dreary and frankly downright depressing, especially by August standards. At noon the temperature stood at just 72 with a thick overcast that promised to linger into the early hours of Thursday.
At the surface Late Wednesday a weak wave of low pressure was cutting a slow but sure path through SE Iowa.
With the wave there was a band or rain but as expected the heaviest held just south of my area. That said, some showers reached along (and especially south of I-80). I had hoped this would hold about 50 miles further south but the system got the better of me and the models. As a result this part of my area had to deal with another sub-par day. Sorry about that. The radar image was captured just after noon.
These are the rainfall estimates as of Wednesday night.
The wave Wednesday slowed the penetration of dry air into the central Midwest. However, the dry air is out there and it has already cleared the skies over the upper Midwest. Notice the dew point spread late Wednesday from 48 in North Dakota to 72 in WC Illinois.
With time the high pressure will drive a dry Canadian air mass into the region clearing skies on Thursday. Here you can see the high situated over the northern Great Lakes Friday night. At that time the rains are well south and west of its center and the Midwest is high and dry.
Check out the difference in water vapor levels from early Wednesday to Saturday.
Saturday's PWAT's. Get a load of that wall of dry air from Western Minnesota and Iowa into southern Illinois.
Saturday water vapor is forecast to be only 30-40 percent of normal in much of this area.
With the slow movement of the high pressure ridge and wall of dry air, the earnest return of moisture should hold off until late weekend or early next week. That should ensure a dry forecast through Sunday evening. Here is the EURO rainfall forecast through Sunday night.
Here are the departures for that period.
With an easterly wind component temperatures are likely going to remain on the cool side going forward, mainly in the 70s for highs. In fact, with a general NW flow forecast for much of the next few weeks the CVSv2 climate model has a decidedly fresh look. Check out the temperature departures in 10 day increments.