Winter storm potential for mid atlantic and new england....

[WXBUFFJIM]

Good morning everyone. A busy time weatherwise as things begin to evolve across the eastern United States. There will be two disturbances to deal with. The weaker one will move through the mid atlantic today into tonight. In the meantime a stronger upper air disturbance will catch up with the first and energize a coastal storm off the delmarva coast Friday night into Saturday. Meanwhile strong high pressure over Quebec will pump cold air into the northeast and Middle Atlantic where moisture will be falling.. Thus significant wintry precipitation is expected in many areas and travel will likely be disrupted due to this, especially Friday night into Saturday as the coastal storm takes over and colder air will be in place.

Breaking down the watches, warnings and advisories, winter storm watches are up for DC, Baltimore, Harrisburg, and Allentown. A winter storm watch means severe winter weather is possible, especially friday night into Saturday as the coastal storm morphs and the cold air wraps around the system. A winter storm warning is in effect for southwestern Virginia and western North Carolina including the triad and the triangle area where a significant ice event of 1/2 inch or more and snow accumulaiton of 3-5 inches is possible tonight through early Friday. Meanwhile a winter weather advisory is in effect for Trenton and Philadelphia tonight through Friday as some light snow and ice accumulation will likely cause hazardous travel later tonight into Friday for the Philadelphia, Cherry Hill, and Trenton areas. Beyond this point, significant snow potential does exist for Philadelphis Friday night into Saturday with some amounts possibly reaching winter storm warning criteria. Likewise for DC and Baltimore. So this is more of a one, two punch, some snow ice and rain, then a significant snowstorm potential for the major cities.

Timing of this brings light snow, sleet and freezing rain to DC, Baltimore, and Philly tonight into Friday. Areas south and east of those cities will likely remain all rain through Friday. However, as the second stronger disturbance moving in from the west merges with the first, a coastal storm will morph and could result in the formation of a strong comma head snow band from DC up through Philadelphia and possibly New York. A strong high pressure system will be situated over Quebec in eastern Canada. Thus the colder air is anticipated to be in place so that any mixed precip will change over to all snow from DC up to New York City Friday night into Saturday. Snow amounts are still a bit difficult to say. However some areas could get over a half foot of snow by the time this is over. Areas north and west of DC, Baltimore, Philadelphia, and New York will especially see a half foot plus of snowfall and possibly near a foot in those areas. However it is still a bit too early to detail the exact amounts for one given area. This is just a trend based on precipitation type, QPF amounts, and the timing of the precipitation. This will likely be adjusted over the next day or two and further updates will be issued on this winter storm later today into tonight.

Also keep an eye out for gale force winds along the northeast and mid atlantic coast. With the full moon on December 8th, any higher than normal tides courtesy of strong onshore flow will likely be enhanced by the full moon given the astronomically higher than normal tides to begin with. Tides could be several feet above normal, thus significant beach erosion and the potential for coastal flooding along the coast.

In summary, while wintry precipitation is forecast to be significant, we can't forget the potential for gale conditions along the coast and some significant beach erosion and coastal flooding problems potentially. More updates later this afternoon and this evening in this developing winter storm.

Jim

[HeartofNC]

Breaking down the watches, warnings and advisories, winter storm watches are up for DC, Baltimore, Harrisburg, and Allentown. A winter storm watch means severe winter weather is possible, especially friday night into Saturday as the coastal storm morphs and the cold air wraps around the system. A winter storm warning is in effect for southwestern Virginia and western North Carolina including the triad and the triangle area where a significant ice event of 1/2 inch or more and snow accumulaiton of 3-5 inches is possible tonight through early Friday.

Jim,

I don't see any watches or warnings yet for the winter storm warning for the triangle through Friday. . . Care to share where I might find this info?

Thanks Tons!

[WXBUFFJIM]

Check out http://www.spc.noaa.gov/products/wwa/

Winter storm warnings are out for western North Carolina. Ashville, Hickory, and Boone, NC are in this warning for mostly significant ice today into tonight. However some snow is possible also. A winter weather advisory is in effect for west central North Carolina. This includes cities such as Charlotte, Winston Salem and Greensboro. Certainly a rough time in west central North Carolina. Be careful and take it slow today and tonight.

Jim

[Garrettj]

I dont understand, peolple have been saying richmond, VA will get 6+ out of this, no where do you say richmond will get any precip, can you fill me in, thanks

[Stephanie]

I just have a Winter Weather Advisory for now:

Severe Weather Alert from the National Weather Service

...ATLANTIC NJ-BUCKS PA-CAMDEN NJ-CECIL MD-CHESTER PA-CUMBERLAND NJ- DELAWARE PA-GLOUCESTER NJ-HUNTERDON NJ-KENT MD-MERCER NJ- MIDDLESEX NJ-MONTGOMERY PA-NEW CASTLE DE-NORTHWESTERN BURLINGTON NJ- OCEAN NJ-PHILADELPHIA PA-SALEM NJ-SOMERSET NJ- SOUTHEASTERN BURLINGTON NJ-WESTERN MONMOUTH NJ-
... WINTER WEATHER ADVISORY FOR TONIGHT INTO FRIDAY...

THE NATIONAL WEATHER SERVICE HAS CONTINUED A WINTER WEATHER ADVISORY FOR MUCH OF CENTRAL AND SOUTHERN NEW JERSEY... SOUTHEASTERN PENNSYLVANIA... NORTHERN DELAWARE... AND EXTREME NORTHEASTERN MARYLAND. THIS INCLUDES THE FOLLOWING COUNTIES...

IN NEW JERSEY... HUNTERDON... SOMERSET... MERCER... MIDDLESEX... SALEM... GLOUCESTER... CAMDEN... BURLINGTON... CUMBERLAND... AND INLAND SECTIONS OF ATLANTIC... OCEAN AND MONMOUTH.

IN PENNSYLVANIA... BUCKS... MONTGOMERY... CHESTER... DELAWARE... AND PHILADELPHIA.

IN DELAWARE... NEW CASTLE.

AND IN MARYLAND... CECIL AND KENT.

SNOW WILL SPREAD ACROSS THE AREA FROM SOUTHWEST TO NORTHEAST TONIGHT. THE SNOW WILL BEGIN CHANGING TO RAIN ALONG THE NEW JERSEY SHORE LATE TONIGHT... AND THE RAIN WILL SPREAD OR MIX FURTHER INLAND DURING THE DAY FRIDAY. AN INCH OR TWO OF ACCUMULATION IS POSSIBLE IN THE ADVISORY AREA BY FRIDAY MORNING. ANOTHER INCH IS POSSIBLE DURING THE DAY FRIDAY... MAINLY TO THE NORTH AND WEST OF PHILADELPHIA WHERE THE RAIN WILL MIX IN LAST.

THE RAIN OR MIXED PRECIPITATION SHOULD CONTINUE INTO SATURDAY... BEFORE TAPERING TO SNOW SHOWERS LATE IN THE DAY AS THE STORM HEADS OUT TO SEA.

REMEMBER THAT A WINTER WEATHER ADVISORY IS ISSUED WHEN SNOW OR OTHER WINTRY PRECIPITATION IS FORECAST THAT WILL CAUSE SIGNIFICANT INCONVENIENCES. WHILE THE PRECIPITATION IS NOT EXPECTED TO REACH WARNING CRITERIA... CONDITIONS COULD... IF CAUTION IS NOT EXERCISED... LEAD TO LIFE THREATENING SITUATIONS. CONTINUE TO MONITOR THE LATEST FORECASTS... AND LISTEN FOR LATER STATEMENTS.

...

[WXBUFFJIM]

The advisory only carries you through Friday. Beyond that Friday night through Saturday, the coastal storm morphs and colder air flows in with moisture falling in that cold air. Heavy snow is possible Friday night into Saturday. So while things could get hazardous from Philly north and west tomorrow, Frdaiy night and Saturday looks even worse potentially. 6 inches of snow is possible in this area Friday night into Saturday.

As for the Richmond area, enough cold air maybe in place for a light snow sleet mixture changing to rain today. Then keep an eye on later Saturday for snow before the precip shuts down as cold air wraps around the coastal storm. There will also be a cold high pressure system supplying colder air into the northeast and middle atlantic states Saturday. Snowfall accumulation Saturday maybe in the 1-3 inch range mainly from Richmond north and west. Even higher amounts are expected north and west of there in the mountains and the skyline drive where a half foot of snow or more is possible in addition to siginficant icing potential. More updates a bit later,

Jim

[Stephanie]

You're right Jim! It'll be interesting!!!

[JCT777]

Good discussion Jim. Thanks!