Preliminary Snow Map for Clipper

A clipper will track across the Mid-Atlantic Friday morning likely bringing a period of moderate snow. The exact track will be key to how much can accumulate in the Washington Region on Friday.

  • Based on the latest high-resolution forecast model below, snow showers or a period of moderate, accumulating snow could develop pre-dawn in the mountains and move into the DC Area during the morning rush hour.  Scattered Snow Squalls are possible Friday afternoon with gusty winds and bitterly cold wind chills. 

nam_3km_18z

Latest Global Forecast System (GFS) model is currently in agreement with the NAM’s track:

gfs_18z

  • Temperatures could fall close to freezing in the suburbs so there is concern that if the current storm track holds, accumulation could occur on untreated secondary roadways impacting the morning rush hour. gfs_7am_friday
  • As of tonight, there is a 70% chance that this remains a conversational event (accumulations remain under 2″ for most) but if model trends continue, this system could turn out to be more of a nuisance (widespread 2 to 4″??) for those of us outside of the urban heat island of downtown Washington. We will know more tomorrow as we try to iron out a track.

030317_preliminary_impacts_dcstorms-com

Here is my preliminary Snow Map:

  • Here is what I think may fall if the current forecast models maintain their current track, amounts may need to be increased or decreased tomorrow morning.

030317_preliminary_snowfall_potential_through_friday

Short-range Ensembles show a range of accumulation outcomes across our region (focus on the bar graph at the bottom of the charts):

National Airport (DCA): 

  • Ensemble Mean (green line) – Dusting
  • Accumulation range: 0 to 1.6″

kdca_2017030115_6snow

Washington-Dulles International Airport (IAD):

  • Ensemble Mean (green line) – Dusting
  • Accumulation range: 0 to 2.3″

kiad_2017030115_6snow

Baltimore:

  • Ensemble Mean (green line) – Dusting
  • Accumulation range: 0 to 1.7″

kdmh_2017030115_6snow

Latest Global Forecast System (GFS) Model:

  • Latest GFS shows a general dusting with pockets of up to 1″ of snow.

gfs_6hr_snow_acc_washdc_9

Latest North American Model (NAM):

  • A higher-resolution model that typically has a colder temperature bias.
  • Given that the GFS and NAM models agree on track and surface temperatures this model can’t be ruled out. 

hires_snow_washdc_49

2 Replies to “Preliminary Snow Map for Clipper”

  1. The wind in this area has been unusually extreme. I had some roof shingles blow off my house yesterday, Gutterman Services http://guttermanservices.com/ is coming to repair them today, I know I wouldnt climb on a roof with the wind we are still dealing with! It be awesome if this wind was really bringing in some snow, hopefully March brings us ‘luck’ like its supposed to!

    Like

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