Rockford’s high temperatures yesterday hit 76 degrees, the first above normal high temperatures in 5 days. The high came amidst increasing clouds as an area of showers and thunderstorms that developed in eastern Iowa moved through the area during the mid-afternoon hours. Officially Rockford saw 0.20” of rain yesterday. The cluster of showers and thunderstorms continued to head east through the evening hours and lambasted the Chicago metro area with torrential downpours and very spectacular and vivid lightning displays. Some rain totals hit over 3 inches of rain in Chicago causing flash flooding on city streets and expressways as the rain came down at a rate over 2 inches an hour.
As a warm front approached the area overnight more thunderstorms developed through the region. Most of the rain cleared the area by the late morning hours. Skies will continue to clear during the afternoon hours. Temperatures should reach well into the 80s, maybe near 90 in some spots that see more sun. Dew points ahead of the approaching cold front are near 70 which will make the day feel more like mid-summer than early fall. This might be the last time we see these types of conditions in the region until late next spring.
The heat and humidity this afternoon will fuel powerful storms associated with an approaching cold front off to our west, currently in the Dakotas and Minnesota. Isolated showers and thunderstorms could develop later in the afternoon, but a more widespread thunderstorms threat with some potentially reaching severe limits will be possible during the overnights hours and lasting into Friday morning. Damaging winds, marginally severe hail will be possible, but the main threat looks to flash flooding with any storms forming this evening and overnight capable of producing torrential rainfall.
Cooler and drier air will start to work in tomorrow, but especially Friday night and into the weekend. After the rain clears the area through the morning hours, clouds will start to clear in the afternoon and winds will switch to the north. Temperatures tomorrow will reach near average for this time of year in the low to mid 70s, but Saturday and Sunday look cooler, but dry. Highs both days should be in the upper 60s in most spots, with overnight lows dipping well into the 40s with clear skies and light winds with high pressure overhead.
36 Hour Forecast:
This Afternoon: Partly sunny, with a high in the middle to upper 80s. Southwest wind 5 to 10 mph, with gusts as high as 20 mph. Isolated showers and thunderstorms possible after 4pm. Chance of rain 30%.
This Evening: Mostly cloudy, temperatures in the 70s. Southwest wind 5 to 10 mph, with higher gusts. More numerous showers and thunderstorms, some severe possible late. Chance of rain increasing to 50%.
Tonight: Showers and thunderstorms likely. Chance of rain 80%. Some storms could produce very heavy rainfall. Low in the upper 60s and very muggy. Southwest wind 5 to 10 mph, with gusts up to 15 mph.
Tomorrow Morning: Temperatures in the upper 60s. Mostly cloudy. Chance of rain 60%, mainly in the morning hours before Noon. Southwest wind around 10 mph, gusts up to 15 mph.
Tomorrow Afternoon: Temperatures in the low 70s. Winds becoming northwest 10 to 15 mph, with higher gusts. Gradual clearing, becoming mostly sunny.
Tomorrow Night: Clearing skies, with temperatures near 50 for overnight lows. West wind 5 to 10 mph.