The dry air in place across the Chicago area has cooled overnight, contributing to
Thursday's daybreak chill. Highs Wednesday struggled to reach 64 degrees -- a
situation that is about to change. Areas away from Lake Michigan are in line for a string
of five 70-degree afternoons, which would be the longest late season 70-degree string
in eight years. October's cool open has been unusual and well below the same period a
year ago. The month has failed to produce a 70-degree high to date, something that
has happened here only once in the last half-century.
The warmth predicted in coming days is linked to a buckling jet stream out West
brought on by a southward plunge of cold early season air. The process is to produce a
powerhouse autumn storm that could drench the northern Plains with the equivalent of
two Octobers worth of rain while burying the northern Rockies under as much as 1-2
feet of snow. The system shifts Chicago winds southeast in coming days -- then
southerly over the weekend, promoting warmer and more humid conditions here.
POWERHOUSE PACIFIC HURRICANE NORBERT MAY SEND RAINY REMNANTS
INTO MIDWEST
--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune
