May 20, 2024. David Waxum. The region has experienced widespread rain and thunderstorms as abundant moisture surges northward, propelled by a warm front lifting into Wisconsin and an approaching low-pressure system from the west. Heavy rainfall occurred overnight, with more periods of intense rain possible this morning. As you head out today, remember to bring an umbrella, as rain is expected through the first half of the morning. However, the Chippewa Valley should see a drying trend by the afternoon, with some potential for pop-up showers or storms later in the day. Clouds will begin to clear, allowing for occasional sunshine as temperatures rise into the 70s.
This evening, a front will stall to our south, while a second low-pressure system intensifies in the Central Plains, moving towards the Upper Midwest on Tuesday. The night is expected to remain mostly dry, although an isolated shower or thunderstorm cannot be completely ruled out. Another significant wave of rain and storms is anticipated on Tuesday as the low-pressure system approaches, placing the region in the warm sector under continued cloud cover. By Tuesday afternoon and evening, there is a heightened risk of severe weather in Western Wisconsin, particularly in southern counties, which are under an Enhanced Risk (level 3/5) for severe weather, according to the Storm Prediction Center.
Despite uncertainties regarding the level of instability due to persistent cloud cover and limited daytime heating, the conditions will support the development of scattered to numerous severe thunderstorms. These storms could bring large hail, damaging winds, and potentially a few tornadoes in the areas under the level 3 risk. Due to the significant threat of severe weather and heavy rainfall, a 13 FIRST ALERT WEATHER DAY has been declared. Winds will become breezy from the east-southeast, with temperatures peaking in the 70s.
By Wednesday, the low-pressure system will slowly lift north and east, leaving behind a few lingering showers and predominantly cloudy skies. Breezy conditions will persist, with cooler air lowering temperatures to the low 60s. Total rainfall from Sunday night through Wednesday afternoon is expected to range between 1-4 inches across the area.
Quieter weather is forecasted for Thursday as an upper-level ridge brings mostly sunny skies and temperatures around 70 degrees. On Friday, another system may bring shower chances, although the exact timing remains uncertain. The system will move away by Saturday, setting the stage for a mostly dry Memorial Day weekend with partly sunny skies and temperatures near to above average in the 70s.
