Sunday Technical Discussion

Synopsis:

The high pressure that has been affecting our weather for the past several days will be moving off the coast as a cold front from the Minnesota snow storm pushes through on Sunday.  The weather on Monday and Tuesday will slowly turn cloudy as another storm system moves in from the south.  Rain will be the story Tuesday night and into Wednesday.  Another short wave will push through Wednesday night into Thursday bringing scattered rain/snow showers to the Commonwealth.

Short-term:

Both models are in agreement that a cold front will be pushing through the region today, but they seem to be 2 hours off.  After looking at current conditions, the line of showers associated with the cold front where at the door steps of the Commonwealth at 13Z.  Never the less, we split the Commonwealth into three zones, for this cold front.  The western zone will see it during the day, the central zone will get cloudy during the day and see it during the evening hours and the eastern zone will remain sunny until the evening hours which will cloud up with the cold front pushing through during the overnight hours.  The GFS shows the showers dying with the cold front for the eastern zone, but never the less the risk is still there for the showers.  Monday starts the transition day as all of the commonwealth will see sunshine during the day.  Our next weather maker will start to bring clouds in from the south late Monday night into our 4 southern zones.

Long-Term:

This is where the weather gets tricky.  The NAM has the next storm shooting off the coast of North Carolina with only Capital and Southeast regions seeing any showers.  While the GFS and the European both have the storm riding up the western half of the Appalachian Mountains.  Because how well the European model has been in the Eastern US, we went with the GFS solution, and threw out the NAM.  Rain will start to enter the Commonwealth Tuesday afternoon starting out 1^st in our 4 southern zones then working north-northeast during the late afternoon and overnight periods.  Showers will linger across the Commonwealth for Wednesday morning according to the GFS.  The GFS also shows another short wave moving in for Wednesday night and for Thursday.  With this coupled with the 540 line being below us, this brings in the chance that snow will be associated with this short wave.  After checking out the critical thickness levels, we went for a rain/snow mix with this short wave as the 1000-850 critical thickness level was still to our north.  After this short wave passes through, our weather becomes more zonal and the 540 line moves back over us.