R.O.V.A. Snow Storm
Snowfall Accumulation by Monday Morning (Low Confidence Forecast for Immediate DC Area)
Tricky forecast between Interstate 70 and Interstate 66…Where does the upper level support (snow maker) go?
Does the upper level support slide due east, chasing the surface low off of Hatteras out to sea keeping the snow across South-side/Central Virginia?
Latest European Forecast Model: Slight Jump to North; trend? or hiccup?
Earlier Euro shows northern extent of snow staying south of NOVA
Latest Euro brings northern edge of snow into Baltimore's southern suburbs
GFS and NAM keep the northern extent of snow along/south of Washington… an inch of snow at best in the Nation’s Capital?Any jump in track of 25 miles would make a huge difference between a dusting and 2 to 4 inches of snow across the immediate Washington Area:
Global Forecast System (GFS): Snow stays at/south of Washington
With the latest model inconsistency, B.S., & uncertainty… I am going to jump on the bandwagon that this will mainly be a R.O.V.A. storm (Rest of Virginia) storm. Sorry N.O.V.A — if you wanted snow we might be too far north this time around 
Latest NAM (North American Model : Short range forecasting): Snow falls as far north as PA/MD line
- Snow now doesn’t even begin until Sunday mid/late afternoon in the D.C. Area… and it’s out of here overnight Sunday.
- If there is a significant change in the model data, I will update my snowfall accumulation map… Sunday morning.
Depressing Snowfall Statistics from December 1st to February 18th: Yeah BOS-WASH (Boston-Washington) Pathetic!
LA NINA’s MARK ON THE EASTERN SEABOARD… DROUGHT DEVELOPING AS WE ARE HEADING INTO SPRING
New England & Mid-Atlantic coastline could use a nice rain storm or snowstorm (image: courtesy NOAA)
How Much Snow Could Fall this Weekend?
Southern Stream Energy is currently over Baja California…
Water Vapor image (courtesy: weather.unisys.com) depicts disturbance over Baja, California
Latest Forecast Model Trends:
- European Forecast model is tracking this weekend’s storm slightly south of the Global Forecast System (GFS) track…
- Storm system may spare much of New England and Upstate New York
- The Shenandoah Valley, Northern Virginia, Washington, Baltimore & Philadelphia are in the *current* ‘zone of accumulating snow’
- New York City is on the northern edge and it is still possible that the Big Apple may miss out on any significant snowfall accumulation.
- A more southern track in this system would deliver an accumulating snow event to the Richmond Virginia Area.
- Timing: Snow may begin as early as Sunday AM or as late as Sunday PM…. ending Sunday night.
- If current trends do continue, the National Weather Service may issue Winter Storm Watches (meaning conditions are favorable for 4″ or more of snow in the next 36 hours) as early as Friday night or Saturday morning.
European Forecast Model from this morning shows snow getting as far north as the New York City Area (courtesy www.weatherunderground.com)
European Forecast Model from this afternoon shows snow getting as far north as the Washington and Baltimore Areas (courtesy www.weatherunderground.com)
Global Ensemble Forecasts show that consensus is building for this system to track up the Carolina coast however there is still some uncertainty in exact track. A difference in track of 50 miles makes a huge difference in any one location of who gets 2" versus 10". (image above courtesy: www.http://mag.ncep.noaa.gov/NCOMAGWEB/appcontroller
Global Forecast System (GFS) produces a hefty swath of accumulating snow from eastern Kentucky to central and southern New Jersey. (image courtesy: www.weatherunderground.com)
Continuing theme of the GFS... BULLS EYE over the Washington Area, Northern Virginia, Shenandoah Valley, Charlottesville VA, much of the state of Maryland, Delaware and the Philadelphia Area. (image courtesy: www.weatherunderground.com)
- So you ask… how much snow COULD fall? Well IF you are under the Bulls Eye and the current moderate CONSENSUS CONTINUES with NO MAJOR CHANGE IN TRACK: FOUR TO EIGHT INCHES OF SNOW WOULD BE POSSIBLE WITH SOME SWEET SPOTS OF A FOOT IN THE HIGHER ELEVATIONS.
- OF COURSE IF SNOW BEGINS EARLIER ON SUNDAY AND TEMPERATURES CAN STAY AT FREEZING AFTER A MILD SATURDAY… WE COULD SEE MORE LIKE SIX TO TEN INCHES OF SNOW…
- THE DEVIL IS IN THE DETAILS… KEEP THE SNOW SHOVELS ON STANDBY….
- STAY TUNED AND HAVE A GREAT (HOPEFULLY WHITE) WEEKEND
Nor’easter Forecast
This mornings European forecast model had a powerful 992 mb storm sitting off of Virginia Beach dropping heavy, accumulating snows along I-95…
Euro Forecast Model image courtesy: weatherunderground.com
This afternoon’s run of the same Euro model has a flatter wave running well to our south out to sea….
Euro Forecast Model image courtesy: weatherunderground.com
Global Forecast System (GFS) has a storm impacting the central and southern portions of our region….
GFS Forecast Model image courtesy: weatherunderground.com
Then the fun image: The Global Forecast Ensemble Models … a “forecasting nightmare”, showing all the very different possible positions of this coastal storm on Sunday… solutions ranging from “clouds” to “heavy snow” to “flurries” to “no snow in the northern suburbs and heavy snow in Fredericksburg, Quantico, Charlottesville, and southern Maryland”.
Global Ensembles.... courtesy NCEP http://mag.ncep.noaa.gov/NCOMAGWEB/appcontroller
** I noticed that the NAO wasn’t forecast to be slightly negative at this point in time (meaning the ensembles predicted a more positive NAO at this time)… this could mean that blocking might be more of an issue this weekend causing some of the model mayhem. I am with all the skeptics… I am not holding my breath but this is the best shot we have had since meteorological winter began on December 1st.
