Late Season Storms

The late season severe storms early Thursday illustrate the point that weather is defined by the atmospheric conditions of the time and not by the calendar.  Baseball size hail, 70 mph wind gusts, and up to four inches of rain would be a bad storm in June or July.  But this is September.  The solar angle is lower this time of year which makes it harder for supercell thunderstorms to form.  But Wednesday night, other parameters made up the difference.  Upper level winds brought spin and shear.  Mid-level humidity and temperature was increasing during the night.  The storms formed and moved along the nose of a low-level jet stream which added plenty of energy to the system.  Had this setup occurred in June or July, the additional solar energy would have made tornadoes more likely.     Meteorologist John Wheeler