Gusty southwest winds will boost temperatures back into the mid 60s this afternoon and again Tuesday before a cold front moves through from the northwest Tuesday night. After a couple days under the influence of cool high pressure (but still above-average temperatures for this time of the year), computer models agree on a big warm-up this coming weekend with record highs in jeopardy both Saturday and Sunday. It is rare for Chicago to experience 70° temperatures in mid November, but once a pattern is established, it is hard to break it down. With the jet stream mean position flow west-to-east along and north of the U.S.-Canadian border, bitterly cold air is trapped in northern and central Canada, and only brief incursions of cool air are allowed to penetrate this far south. Warm air holds much more moisture, and converging winds produce strong uplift and instability, so cold frontal passages will trigger thunderstorms and the potential for severe weather.
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
