Monday's 86-degree reading (the city's highest temperature thus far this season and
the warmest in nearly eight months) yields to cooler air today, but heat returns
Thursday -- and persists. Chicago's temperatures have climbed to 80 degrees or higher
on only four days this year (17 days by this time last year), but forecasts on five of the
next seven days contain readings above 80 degrees. Higher humidities, too, will
accompany the arrival of this season's first multi-day stretch of summer warmth. It's
also likely to be a turbulent period. Computer models indicate a powerful 70-90 m.p.h.
jet stream shoots from Missouri into central Illinois today, and that will enhance
thunderstorm development. Other disturbances sweep across the area Thursday and
Friday and again on Monday, and thunderstorms will accompany each of these events.
SEVERE THUNDERSTORM POTENTIAL
Chicago sits within a 30-percent-chance area Tuesday. That means there is a 30
percent chance that a severe storm will occur within 25 miles of any given point.
--By Richard Koeneman, WGN Weather Center Meteorologist
