Re: Freezing Rain THREAT Sunday in Western VA/Western MD/Eastern WV
not really…. here is why.
This image shows the current readings as of 11:00 p.m. the areas I have circled in red represent key areas that show the temperature and the Dew point. Fr example Charlottesville has a temperature at 11:00 p.m. 34° with a dew point of 23. This means that when the precipitation starts temperatures will drop down to around 30 degrees and that would support either ice or freezing rain or snow.
Richmond has a temperature of 34° also with the dew point of 25 so when the precip begins… The temperature will fall and the dew point will rise. This is referred to as the wet bulb or the saturation point. A temperature of 34° and a dew point of 25 means that the saturation point will be around 30° in Richmond — if the precipitation were to start before dawn…. would support sleet or freezing rain. Roanoke Virginia has the same sort of temperature and Dew point. Washington DC has a temperature of 28° with a dew point of 24 — so when the precipitation starts the temperature will be around 26°. And in Frederick and central Maryland they have a temperature of 30° so the dew point of 28 which supports a wet bulb or saturation of 29° and again freezing rain and sleep if the precipitation were to start during the overnight hours.
BUT … The problem is that because the system is tracking well inland when the precipitation comes in on Sunday morning… south winds will cause temperatures and the dew points to rise rapidly. This image shows the temperatures at 8:00 a.m. and at 10:00 a.m. on Sunday and you can see how rapidly the temperatures rise even in the normally colder locations such as the mountains of southwest Virginia…. the Shenandoah Valley …western and Central Maryland ...and the eastern panhandle of West Virginia.
Another problem is that by the time the main precipitation moves into Virginia Maryland Delaware southern Pennsylvania New Jersey and West Virginia temperatures will have warmed and the precipitation will come in mainly as rain. This image shows how the rain will advance rapidly from its position at ATM on Sunday to 11:00 a.m. Notice that the pink color does support Freezing in the Valleys of Southwest Virginia and the Central Shenandoah Valley but because the temperatures are warming rapidly the icing situation does not look to be significant in any way.
By 3:00 p.m. on Sunday the rain is pushed into almost as far north as Philadelphia and southern New Jersey Moderate rain will cover all of Delmarva … central and eastern Maryland… all of Virginia and North Carolina. There may still be some light freezing rain in the valleys of the Shenandoah Valley as well as the eastern panhandle of West Virginia and western Maryland but again the temperatures will be very marginal for any kind of icing.
Moderate snow in interior new England Sunday night into Monday…. More on that Sunday am.