Friday's predicted 50s won't last long. A southbound blast of cold Canadian air is on
the move beneath powerhouse 150+ m.p.h. jet-stream-level winds. The chill's arrival
will become noticeable in Saturday's predawn, possibly encouraging some rain in the
area to mix with or change to wet snow away from Lake Michigan. But the cold air's
impact becomes most noticeable as howling north winds take hold and send
temperatures into a slow, steady decline beneath wintry gray skies. This is expected to
yield snow showers at times Saturday. Weekend temperatures are to be the coldest of
the fall season to date and the chilliest since last March.
The cold blast is just one of three predicted to arrive at regular intervals over the
coming week. The second one sweeps in Monday and a third is due Thursday.
Persistent warmth aloft which induces a northward buckle in the jet stream for the next
two weeks over North Atlantic appears likely to encourage northwest winds to flood
into the lower 48 states. Thus prolonged warming is not in sight.
U.S. NOVEMBER SNOW COVER IS NEARLY 5 TIMES THAT OF A YEAR AGO
--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune
