As the northern Plains states bake under 100°-plus heat and high humidity, Chicago will experience close to a “typical” mid-July day today with high temperatures reaching into the mid 80s.
The upper-air jet stream pattern will change very little in the next couple days with a huge ridge of high pressure out west and a deep low-pressure troughing effect over the eastern United States. This will result in Heat Advisories over the Dakotas and just a slow increase in humidity and a possible introduction of scattered showers or thunderstorms in the forecasts here.
The jet stream flow will modify slightly toward the end of the work week, but the primary storm track for low pressure centers will be west-east across southern and central Canada. We anticipate just one “cool” frontal passage in northeast Illinois during the week ahead on Friday, ending the chance of thunderstorms and dropping humidity significantly next weekend.
--By Paul Dailey, WGN Weather Center Meteorologist
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
