Vince_Condella's Blog

Does it get any better than today?  July 1 has been a beauty, with full sunshine and temperatures in the 80s.  Most important is the low dewpoint, only in the low 50s early this Tuesday afternoon.  This dry airmass is known as cP, or continental Polar, according to the designation of air masses from the early years of the 20th century.

cP air that we have today has been modified by the high summer sun.  But the continental part of the name means the air mass originates from land and not water.  The polar part of the name means it originated in Canada.  At least it did yesterday.  Today, however, the wind is from the southwest and our air parcels are arriving from the central Plains - Nebraska, Iowa, and Missouri.  Plus, the summer sun is heating the air mass and it is not a true polar origin.  It has become a cT air mass, continental Tropical.

Tomorrow (Wednesday) we will feel a touch of mT air, or maritime tropical.  It will originate over the waters of the Gulf of Mexico.  Dewpoints will jump into the 60s as air parcels sweeping from Texas, Louisiana and Alabama curve north and northeast into Wisconsin.  The higher dewpoints will combine with an approaching cold front to produce afternoon showers and thunderstorms.  The cold front will act as the lifting mechanism for the moist air near the ground.  Some of the storms may be strong.

Once the cold front sweeps through our area Wednesday evening, watch for a cooler and drier air mass once again for Thursday.  This will be another shot of cP air, with air parcels arriving from central Canada, well away from any source of ocean water.