It was a brutally hot and humid day out today, with temperatures in the low 90s for many, and heat index values into the triple digits throughout much of the afternoon. Some locations saw heat index values close to 115° at points during the afternoon, as dew points remained well into the 70s and even low 80s for some at points. Officially, the high temperature in Rockford made it up to 94°.
Luckily, we do have SOME relief on the way. Not much in the way of humidity drops, but certainly in temperatures. Overnight tonight, a few waves of showers and storms looks to roll in, mainly after midnight. Temperatures fall only into the mid 70s due to heavy cloud cover and moisture limiting the cooling we could see.
Tomorrow, we keep the humidity, but temperatures are a smidge lower, only topping out in the mid 80s. This is a bit conditional on the potential sunshine we could see during the afternoon, so if we stay cloudy and rainy for most or all of the day, our high temperature could be much lower.
So if we time out these waves of showers and storms, we get a picture that looks like this: The first wave comes through after midnight Sunday morning, and continues through into Sunday morning. We get a short break late Sunday afternoon and evening, but a second wave comes through for Monday, bringing another set of rain showers and isolated storms for much of the day. These will be associated with a cold front, so they will cool us down quite a bit past Monday.
These rain showers could be heavy rain producers at times, as the environment is prime to see rainfall rates of up to 0.5 to 1.5 inches per hour. Total rainfall amounts could reach up to 3 to 5 inches, particularly across Southern Wisconsin. Other locations further South still could see up to an inch of rain. Flash flooding remains a potential risk across Southern Wisconsin.
We remain much cooler past the rain showers and storms Sunday and Monday, with another isolated chance for showers Tuesday, but we look to remain cooler and drier through the end of the work week and into next weekend.