The Threat of Thunderstorms Increase Tonight, Some Stronger

The big weather talker today besides temperatures cooling off today along the lakeshore will be a threat of showers and thunderstorms tonight.  A warm front will lift northward with good dynamics to fire up a few stronger storms.  The chance of widespread severe weather does not appear to be likely; however, a few storms could contain gusty winds, hail, and brief heavy downpours.  The heaviest rainfall, per our model data, has been trending a little farther north.  Streams and rivers could rise a bit in a few locations, and minor ponding or flooding in a few areas is not out of the question.

The big source of energy will be a strong low level jet feeding warmth and moisture into these storms, and an always important lifting mechanism, a front.  With higher amounts of energy in the atmosphere, a risk of gusty winds embedded in the thunderstorms is possible.  Precipitable water values (the amount of water in the atmosphere when squeezed out) will be over an inch with these storms.  The fun part of spring storms is when there’s enough cold air around the low, you will see snow developing in the northern and northwestern tier of the storm, which is exactly what will happen with snow possible Thursday in extreme northern Wisconsin.

The timing of storms are always key! Besides a couple of isolated showers this afternoon, the main event will take place later tonight after midnight.  Most, if not all, of the rain and storms should be east by the early morning commute.  Thursday will be a very windy day in the wake of the storm system with the tightening of the pressure gradient.  Winds will crank out of the west 15-30 mph.