Weather Forecast and Climate Update
Introduction to Weather Forecasting
Weather Maps
Interactive Radar
Climate & Environment
FRIDAY NIGHT: Mostly cloudy and modestly cooler. A few lingering spotty showers possible during the evening. Low: 43.
While it won’t be a complete washout by any means, the opening weekend of May will feature a fair amount of cloudiness and on and off showers. At this point, the best chance for seeing rain looks like early Saturday morning, then again at times Sunday afternoon continuing at times into Monday.
Blocking Pattern and Its Effects
Blocking pattern produces two cut off lows across the U.S.
The culprit behind the extensive cloudiness, cool weekend temperatures, and occasional showers? Two cut-off lows: one will spin across the Ohio River Valley and the other will be across the Southwest over the next several days. They sit beneath a ridge due to “Rossby wave breaking” typical in Spring as the jet stream slows down and is more inclined to buckle or retrograde.
Rossby wave breaking refers to the phenomenon where large-scale atmospheric waves tend to break and distort their shape, leading to significant impacts on the overall weather pattern and climate, particularly in the mid-latitudes. This breaking process can cause air mass mixing between high and low latitudes, influence precipitation patterns, and even contribute to extreme weather events like heat waves and floods.
This results in a cool pattern with added clouds but also the Canadian air is advected southward around the mid-level trough circulations.
Weather Resources
Weather Maps
Weather & Climate News
Interactive Radar
Weather Bug Cameras
7-Day Outlook
Weather Center Newsletter
Current Weather Conditions
Current Conditions
Short-Term Forecast
Next Few Hours
Long-Term Forecast
Looking Ahead
Rainfall next three days
Light amounts expected across the Chicago area. The heaviest rainfall totals cumulatively the next three days will fall across the Ohio Valley and into portions of the Eastern U.S.
Weekend temperature forecast
It will be cool for most of us as the opening weekend of May will feature highs well below the typical mid to upper 60s considered normal for early May.
9-day temperature outlook
Temperatures will gradually warm for almost everyone by the end of this forecast period. By late next week, almost 300 million U.S residents will see at least 70-degree temperatures with 70s nearly coast to coast.
Temperature anomaly next 7 days
A cooler than normal pattern across the nation’s midsection is tied to the “cut off” low pressure system.
