Saturday Evening Update on Potential Blockbuster Nor’easter

Blustery cold view of the Nation’s Capital from the Netherland’s Carillon in Arlington, Virginia

Headlines (based on the latest model data that just came out):

  • Heavy Snow with 1 to 2″ per hour accumulation rates likely Monday evening through Tuesday morning; Scattered snow showers continuing Tuesday afternoon & evening.

 

  • Depending upon which model you look at, Sleet and or Rain could mix in along and east of interstate 95. This storm currently looks like a High-Impact event with most forecast models dropping between 5 and 10″ of snow (where no change-over to rain/sleet occurs). 

 

  • Phasing does not look to occur with this system until it is off the coast of New England; some models suggest the storm could track further east meaning southern Maryland and the eastern suburbs are not out of the woods and western zones could therefore end up seeing less snowfall accumulation if the track does shift east (this will be ironed out overnight and Sunday morning).

 

  • Damaging winds are possible Wednesday (gusts in excess of 50 mph) with widespread snow squalls & the potential for additional accumulations with temperatures holding at or below Freezing and wind chills ranging in the teens to teens below zero (wind chill advisories may need to be issued Tuesday night & Wednesday).

Latest GFS operational forecast model:

  • Upper level trough (seen over Michigan) remains separate from the upper-level disturbance (coastal NC/VA) suggesting a non-phasing storm until it is well off the coast of New England.  This suggests to me that this Nor’easter will be a fairly quick-moving system

  • 18Z GFS surface map showing rain and snow (8PM Monday through 8PM Tuesday)

GFS Trend for Tuesday morning at 8AM (when the Nor’easter should be right tracking off of our coastline):

  • Rain/Snow line still in play across southern Maryland and the Eastern Shore

Latest 18z GFS Operational Snowfall Accumulation Potential (image courtesy WxBell):

Latest North American model (NAM):

  • The latest NAM model tracks the upper-level disturbance from the mid-south (look at the bright red/orange colors over south-central Tennessee in the beginning of this image loop) into southeastern Virginia and then inland across Long Island and southern New England.

Latest NAM showing potential surface track:

  • Heavy, quick-hitting Snowfall with tremendous snowfall rates, but if this model is correct, the heaviest snow would remain across the northern and western suburbs with lots of heavy rain/sleet across central Virginia into Long Island.

NAM model Trend:

  • “You’re killing me smalls” with your wobbling “uncertain” track!

Latest NAM Snowfall Potential (if the 18z operational model is correct):

Latest Canadian model:

  • More of a classic offshore track but still a very fast mover as the upper-level trough over Michigan may not unite (phase) with the system off of the Mid-Atlantic coastline.

Canadian model showing potential surface track:

  • Heaviest snowfall accumulations would favor interstate 95 corridor

Canadian Model Trend:

  • Low pressure “bombs out” (rapidly deepens/rapid pressure fall) with thunder-snow and snowfall rates over 2″ per hour Tuesday morning across the DC to NYC corridor!

 

  • Western zones of DC Region (Shenandoah Valley) would receive much lighter snowfall accumulations with heavy rain/sleet across lower southern Maryland

Latest Snowfall Projection from Canadian Model:

  • Notice the Foot or more right across the Fredericksburg-DC-Baltimore 95 corridor!

Latest European Model:

  • Like the Canadian above, shows a very impressive 994mb low (category 2 hurricane) sitting off the coastline.

 

  • Notice the upper level trough (blue area over Michigan, circled in red) remains un-phased (not united/separate) from the surface low.

 

  • Nice blocking over eastern Canada, however North-Atlantic blocking not as impressive… again, I am seeing this being a fast-moving storm system!

European Ensemble:

  • Slight shift eastward among its various members which is good if you want snow along interstate 95 … (will it continue to slip too far east in tonight’s 00z run pulling the heavier snow east of DC?)

 

Latest European Operational Surface Maps:

  • 2AM Tuesday (heavy snow falling in DC, Baltimore and northern Virginia with sleet and rain across southern Maryland

  • 8AM Tuesday (mixing once again an issue across Fredericksburg, southern Maryland and eastern shore, heavy snow predominant precipitation type in DC and Baltimore’s immediate northern and western suburbs.

Latest European Snowfall Guesstimate for DC and the entire BOS-WASH Northeast Corridor: 

The latest European model makes me wonder if the NAM model is full of $hit.

Check out the latest European Meteograms for the major three airports:

National Airport – bottom of graph… total snow… 9″ possible.

Dulles:

  • Currently suggesting 8″ (again the latest European operational is a bit further east in track than the GFS)

Baltimore-Washington-International:

  • 10″ of snow doesn’t seem unreasonable if the trends hold.

Finally from the folks at the National Weather Service in Sterling (www.weather.gov/lwx):

I’ll issue my own snowfall map tomorrow after I see the overnight run of the latest European and the North-American Model.

Again, we are currently seeing a good probability of a plowable snow across parts of the region.  The exact track still needs to be ironed out so those of you in southern Maryland, you’re not out of the woods. Those of you who think you might be in the bulls-eye… if this system follows the Canadian and European trends… the heaviest snow could still shift to your east. 

Stew and Chew folks… stew and chew on all this data!  Print out yo’ own map and show yo’ friends.  Now y’all know why meteorology is the only business when you can be wrong 100% of the time and still receive a paycheck. 

Have a fantastic Saturday evening!

 

 

 

 

 

 

One thought on “Saturday Evening Update on Potential Blockbuster Nor’easter

  1. Jason

    Boy is this fun to follow. And nervous. I have visions (nightmares?) of waking up Tues morning to one inch or less. I hope for 5″ or more.

    Like

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