Heavy rainfall on the order of 3-5 inches will mean we’ll have to be on heightened alert for flash flooding early on and then river flooding late-week into the weekend.
Current jet stream forecasts show the river of air at the top of the atmosphere to be moving fast right overhead. This will allow several fronts to enter the area and move along under the jet. This is a classic set-up for flash flooding (and perhaps severe weather).
First, thunderstorms are exiting this evening. Our next bout of wet weather will come late Tuesday night with a round of potentially damaging thunderstorms. These storms will race across Iowa during the late-afternoon and evening hours of Tuesday. I expect them to cross the Mississippi between 10pm and midnight and affect Northern Illinois during the wee hours of Wednesday. The main threat with this batch will be very heavy rainfall amounts and damaging wind.
Additional thunderstorms are likely Thursday and then again Saturday into Sunday.
Posted under flooding, severe weather
This post was written by Eric Sorensen on May 31, 2010














As we go through the afternoon, a few widely scattered showers and storms are possible. Our warm and humid atmosphere has allowed a few cumulus clouds to take off and build vertically. You may have heard us talking about the convective temperature being a guide as to when these storms take off. Once you surpass this temperature, storm development is possible. Today’s convective temperature is in the lower 80′s and with temperatures near 90 around the Stateline, we have begun to see some storms pop up. Any showers that do develop may produce some small hail and a few gusts of wind, but will be very short lived.




