Vince_Condella's Blog

It has happened again.  Another entry can be made in the record book for November in Milwaukee.  You may recall yesterday that we set a new record high for the day of 73.  It was also the second warmest presidential election day on record for Milwaukee, with weather records going back to the 1800s.

Our friends at the National Weather Service in Milwaukee-Sullivan tell us today is another rare day.  Mitchell Int'l. Airport reached a high of 70 degrees at 1:35 p.m. before the wind turned southeast and cooled us down quickly.  We have now had 3 consecutive days with highs of 70 degrees or higher in Milwaukee, and that has never happened since weather records began in 1871.  Never happened.  That's pretty significant.

Our record high for today is 73 degrees set in 1978, and we may have gotten close to that one except Lake Michigan got in the act and put us in the big chill along the lakeshore.

A surface low-pressure center from the west is slowly approaching, and has been doing so for the past 4 or 5 days.  As it gets closer, the pressure gradient increases.  The pressure gradient becomes larger as atmospheric pressure changes rapidly over a certain distance.  You may notice on a weather map that isobars get packed closer together.  Isobars are lines of equal pressure.  When they appear packed tightly together, it means the surface pressure changes rapidly with horizonal distance.

Dark lines are isobars, or lines of equal pressure.  When they are packed tightly together, it means there are large atmospheric pressure changes and strong wind.

An increase in pressure gradient also increases the surface wind and begins to curve the wind in toward the center of the low-pressure center.  That curving, due to frictional effects of the Earth, allowed surface wind this afternoon to shift from south to southeast.  It was a subtle shift but enough to dramatically drop temperatures along the lakeshore into the 50s.  Meanwhile, those of you west of Highway 45 were still enjoying highs around 70.

Thursday the low-pressure gets a little closer and rain showers begin to move in during the afternoon.  This will bring an end to our mild temperatures.