Slowly Developing Two Part Storm for MD. The system Sunday night through Tuesday will be a complex Clipper bomb. The initial mid-level short wave Clipper will slowly push across the mid-Atlantic late Sunday night and into Monday with widespread 1-3 of snow south of DC and more north and west. The latest 6Z GFS model projection in the first image shows the band of light snow across central MD, PA, and VA at 7:00 AM Monday morning. However, from Monday morning and onward, the initial Clipper energetics will quickly transfer offshore and the associated precipitation field will dissipate Monday morning into scatter snow showers. How quickly the precipitation transfers off shore will determine the extent of the dreaded dry slot that may develop over MD. The second image shows the GFS model at 7:00PM on Monday with a strong coastal low beginning to form off the Ocean City coast, and remnant scattered snow showers across Maryland (being aided a bit by the moisture from the coastal low). Note: this could very likely be a significant coastal erosion event for the Delmarva Peninsula. Watch out for some coastal flooding there. By 7:00 AM on Tuesday (third figure), the coastal low is intense and pounding New England with over a foot of snow (two feet perhaps in New York City) and Blizzard conditions along the coast. However locally, the impacts will depend on wrap-around snow at this juncture of the storm. In the third figure, GFS brings a pretty decent wrap-around snowfall band into northern DE, northeast MD, and eastern PA. However, just below this band is a strong dry slot from Lewes, DE and locations south (i.e. no snow really falling, dry air being wrapped in). The timing and location of this wrap-around snow and adjacent dry slot will be critical for determining the final snowfall totals. Right now, most of the major global models agree on some wrap-around snow from Baltimore and locations north and east, so Ive included those totals in my forecast. HOWEVER some important notes on wrap around snow: 1) models notoriously over-do wrap around snow in our area; 2) Clipper bomb system in the past have be big snow makers along the coast, and not so much inland. 3) Therefore I suppressed some of the snowfall totals north and east of Baltimore (map in figure 4) compared with what you may see elsewhere. --- SNOWCAST INFO: The fourth figure is my snowfall map through Tuesday night. For locations northwest of Baltimore, most of the snow will arrive Sunday night and through mid afternoon on Monday. I anticipate 2-4 by mid-Morning in places like Westminster, with the chance for an additional inch or two associated with some of the scattered showers during the day on Monday. The story will be much different northeast of Baltimore in places likes Bel Air. By Monday morning at sunrise, perhaps only 1-2 will be on the ground... but these locations have the best chance of getting 4 or more additional snow as the storm intensifies Monday evening and into Tuesday. Because of the questions associated with the dry slot and wrap-around snow, these areas (NE of Bmore) also holds the greatest BUST POTENTIAL (including the upper Delmarva Peninsula). More details will be available by this evening for a more refined forecast. Closer to Philly should safely get into the coastal moisture so more than 7 is a good best there. ** I WILL POST A FINAL CALL AFTER DINNER TONIGHT ** LIKE AND >SHARE!
Posted on: Sun, 25 Jan 2015 14:39:02 +0000