Thunderstorms return for Memorial Day weekend

 

Thursday was an absolutely beautiful afternoon with plenty of sunshine and temperatures warming into the upper 70s and low 80s. While there were a few isolated storms across central Wisconsin this afternoon our skies locally remained clear and will stay clear through the night. Overnight temperatures will dip into the mid and upper 50s, rising back close to 80 degrees Friday.

A couple things we need to note and monitor for Friday will be the rise in humidity as dew point temperatures warm back into the 60s. This could help sustain thunderstorms that'll be moving in from the west. The storms are likely to remain west of the Mississippi River through sunrise, shifting east mid to late morning.

There are still some questions regarding whether or not the storms will weaken some as they move into northern Illinois and southern Wisconsin Friday morning. If the storms don't move in until later in the morning there may be enough instability that builds up to allow the risk for severe storms to increase through early afternoon before shifting east towards Chicago later in the day.

The Storm Prediction Center has placed all of northern Illinois and southern Wisconsin under a slight risk for severe storms Friday. Biggest threats would be damaging wind gusts. If, however, the storms weaken some through the morning a few outflow boundaries left over could interact with a northward shifting warm front, slightly increasing the potential for some low-topped supercells which could produce brief tornadoes.

Friday night will be dry as high pressure moves in from the west. This will pave the way for a fairly decent Saturday with temperatures warming into the mid and upper 70s.

Another system moving in from the west and southwest late Saturday night will increase the chance for some heavy rain producing thunderstorms Sunday morning. Another warm front will be pulled into northern Illinois coming

very close to the I-80 and I-88 corridors. Low pressure moving across northern Illinois during the afternoon will bring a few severe storms across the central part of the state. The highest risks right now will be across southern Illinois. It's possible the severe threat could shift north near the state line, especially if the warm front lifts further north as well. Sunday will also be a day to monitor this weekend.

Cooler air will filter in behind the low for Monday which will give us scattered rain showers and temperatures in the upper 60s and low 70s.