This December 30 event first appeared on my radar screen back on December 21-22… But there even some hints of this system before hand. I am doing things a little differently this winter in an attempt to finesse my skills in detecting significant winter weather events beyond 7 days and so far there been 2 significant events– the DEC 20-22 Midwest winter storm and the just ended December 25-26 event… which I detected over 12 days before they actually developed. In fact my first post on the potential for significant eastern U.S. winter storm for DECEMBER 25-26 was first made back on December 7.
Each particular event has certain characteristics which a meteorologist must take a look at and consider as he / she makes a forecast for the client or the general public. For example with a recently just ended DEC 26-27 winter storm… the DOMINATING characteristic was that the main or primary LOW would track into Tennessee and perhaps southeastern Kentucky as a fairly strong system. And that in turn would dislodge the cold air over the northeast U.S. and force the precipitation to change to rain pretty quickly.
In this upcoming situation for December 29-30 things are of course… vastly different.
- This Low is not going to be nearly as strong and the initial stages as the DEC 25-26 Low.
- This is going to be a pretty fast moving system so the actual interval of moderate or significant precipitation is not going to last that long and it is imperative that one does not over forecast too much snow.
- This Low IS going to BOMB OUT southeast of Cape Cod and it’s probable that much of southeastern Massachusetts could see over 12″ of snow from this system.
- Over all of central and south central Virginia the low level temperatures near the ground will be too warm to support ALL snow what the START of the event.
This particular aspect of this Low I have been talking about for the past three or four days— that even though the Middle and Upper levels of the atmosphere will be cold enough for all snow in the Richmond metro area… the temperatures in the last 2000 feet near the ground may be above 32 degrees F. As a result I think that the precipitation at least for the first half of the event over the Richmond metro area will be rain and snow mixed which to most people will probably appear as all rain . Then as the Low pressure area moves off the Virginia Coast and the cold air comes at the surface the precipitation hands as snow .
The one thing that could change this and make it colder and snowy are for the Richmond metro area would be for the precipitation that come down harder / heavier which would pull down enough cold air to the surface so that the precipitation would fall as snow even at the ground level. That is a possibility although it is NOT a likelihood at this point.
The short range model data clearly shows a significant band of moderate precipitation running from Tennessee and southeastern Kentucky into southwestern Virginia up through the Roanoke Lexington area and into much of eastern portions of West Virginia and the Shenandoah Valley. I suspect this area will see the best snow because they also have the coldest low level temperatures.
If you cannot find your location on this map PLEASE go back High school OR please stop reproducing… and give up your right to vote.
The one area that could see the least snow …or the biggest BUST in the northeast would be northern NJ and New York City. And the area that might be the biggest winner with this snow would be Eastern Long Island Rhode Island and southeastern Massachusetts including martha’s vineyard Cape Cod and probably Boston