[Cambium]

Future radar loop. White is snow not clouds. Light snow tonight then the 27th storm you can see rounding the base at the end here.
http://hp6.wright-weather.com/eastnmm.shtml

[urbanmyth]

Originally Posted by Cambium

PRECIP WILL TRANSITION FROM SNOW/SLEET TO RAIN WED NIGHT AS MID
LEVEL WARMING ADVANCES NORTHWARD. THIS PROCESS WILL BE QUICK IN
THE COASTAL PLAIN AS E WINDS WARM THE BOUNDARY LAYER.

ICE WILL ALSO BE A CONCERN IN THE INTERIOR INCLUDING THE CT VALLEY
AS SFC COLD AIR MAY GET LOCKED IN AS THE CHANGEOVER OCCURS WITH
SEVERAL HOURS OF FREEZING RAIN POSSIBLE.

Thanks Cambium. Sounds like "winter" inthe Piedmont of NC and VA. It's a little early, but do you have a feeling yet about snow chances this weekend?

Cheers!

[7 Wishes]

Just looked at the OKX description. Looks like they're thinking snow for all to start, then change to rain on the coast (though staying a mix in the area covered by this thread), but no more than 1-2" anywhere. They are concerned about icing in the interior:

CATEGORICAL POPS WARRANTED BY EVENING...AND BOUNDARY LAYER TEMPS...FORECAST PROFILES AND PARTIAL LOW LEVEL THICKNESS WOULD SUGGEST SNOW TO START...WITH A QUICK CHANGEOVER TO RAIN NEAR THE COAST...SNOW TO A MIX ACROSS THE NORTHERN SUBURBS INCLUDING COASTAL CT...AND ALL SNOW INLAND DURING THE EVENING. PRECIP TAPERS OFF TUESDAY MORNING.

THERE COULD BE SOME LIGHT ICING HOWEVER ON TOP OF THE INCH OR TWO OF SNOW LATE AT NIGHT DUE TO LOSS OF ICE NUCLEI IN THE CLOUD LAYER WITH PRECIPITATION GENERATION IN THE -10C OR WARMER CLOUDS. LIGHT FZRA LIKELY BY THAT TIME. THIS COULD MAKE FOR SOME SLICK TRAVEL BY TUESDAY MORNING. WILL ISSUE WINTER WX ADV FOR INTERIOR LOCATIONS.



Still a lot of uncertainty in their mind with Wed-Thurs, including a possibility it doesn't start until very late Wed. but sounds like they're thinking rain coast/snow inland and a lot of wind:

SOME WAVERING WITHIN A 50-75 MILE SWATH STILL EXISTS WITH THE TRACK OVER THE NYC METRO AREA...BUT HOPE IS FOR A BIT MORE CONSENSUS AS THE RESPONSIBLE PAC SHORTWAVE GETS BETTER SAMPLED FROM THIS MORNING ON. THE EXACT TRACK WILL DETERMINE PTYPE...BUT THIS CONTINUES TO LOOK AS MAINLY A RAIN EVENT FOR THE COAST WITH A STRONG EASTERLY COMPONENT TO THE FLOW...AND A WINTRY MIX FOR THE INTERIOR. THE EXACT TRACK OF THE STORM WILL DETERMINE PTYPES AND AMOUNTS ACROSS THE INTERIOR...BUT A PERIOD OF HEAVY WET SNOW TRANSITIONING TO SLEET AND FREEZING RAIN IS LIKELY. THERE HAS BEEN A NOTICEABLE TREND OF A SLOWER APPROACH OVER THE LAST FEW RUNS...WITH MAIN IMPACTS NOW EXPECTED LATE WEDNESDAY INTO EARLY THURSDAY MORNING. HAVE TRENDED FORECAST IN THAT DIRECTION. MAIN IMPACTS LOOK TO BE STRONG EASTERLY WINDS...HEAVY PRECIPITATION AND COASTAL FLOODING LATE WED INTO THURSDAY MORNING. IN TERMS OF WINDS...25 TO 40 MPH SUSTAINED EASTERLY WINDS AND GUSTS OF 50-60 MPH ARE POSSIBLE. HIGHEST WINDS WILL BE ALONG THE COAST AND HIGHER ELEVATIONS. NW WINDS BEHIND THE STORM WILL NOT BE AS STRONG. STRONG WINDS COMBINED WITH SATURATED GROUNDS AND/OR WINTRY PRECIPITATION WILL LIKELY RESULT IN DOWNED TREES AND POWER OUTAGES.



Finally (and most interestingly), they are thinking about a possible high possibility that the Dec. 30-31 storm stays to the south and goes OTS:

MODELS STILL INDICATING LARGE DISCREPANCIES IN THE SYSTEM NEXT WEEKEND...BUT POTENTIAL FOR ANOTHER NOR`EASTER. GFS REMAINS WELL OFFSHORE AS DOES ALL MEMBERS OF THE GEFS. 12Z EC HAS TRENDED MORE TOWARDS THE GFS AND SHIFTED SOUTHWARD. LOW CONFIDENCE FORECAST...BUT THERE IS THE POTENTIAL FOR ANOTHER HIGH IMPACT EVENT.

[Cambium]

Speaking of track... here's HPCs thoughts. Amazing being that they had this going up the appalacians 2 days ago. Now showing to exit over Long Island.

Do you guys know we wil be missing a 12" snowstorm by 100 miles?? If this thing was south by 100-125 miles we would be in the 8-12" range.

HPC Winter Weather Forecasts

[ctwhitechin]

Originally Posted by Cambium

Speaking of track... here's HPCs thoughts. Amazing being that they had this going up the appalacians 2 days ago. Now showing to exit over Long Island.

Do you guys know we wil be missing a 12" snowstorm by 100 miles?? If this thing was south by 100-125 miles we would be in the 8-12" range.

HPC Winter Weather Forecasts

always amazed me how just a little shift can change things, me personally I'm glad have elderly relatives supposedly staying with us Friday-Sunday would prefer no snow for them to slip and slide on.

[btownboss4]

Originally Posted by Cambium

NWS Boston agrees with my thinking. Accumulating Snow to start then changing to rain BUT... read last paragraph. If cold air gets stuck at the surface, ice ontop of accumulating snow will cause some outages depending on how much ice falls!

BRUNT OF THE STORM WILL OCCUR DURING THIS PERIOD AS STRONG
EASTERLY LOW LEVEL JET TRANSPORTS MOISTURE NORTHWARD INTO SNE.
PRESENCE OF SFC RIDGING AND EVAP COOLING FROM LOW LEVEL DRY AIR
WILL PROVIDE SUFFICIENT COLD AIR FOR THE PRECIP TO START AS SNOW
OR SNOW/SLEET MIX FOR MOST OF SNE EXCEPT FOR THE IMMEDIATE S
COAST WHERE MAINLY RAIN IS EXPECTED.

PRECIP WILL TRANSITION FROM SNOW/SLEET TO RAIN WED NIGHT AS MID
LEVEL WARMING ADVANCES NORTHWARD. THIS PROCESS WILL BE QUICK IN
THE COASTAL PLAIN AS E WINDS WARM THE BOUNDARY LAYER.
HOWEVER...PARTIAL THICKNESSES SUGGEST SEVERAL HOURS OF SNOW N OF
THE MASS PIKE AND WEST OF I495. EARLY ESTIMATES ARE FOR 3-6" OF
SNOW IN THIS REGION WITH HIGHEST AMOUNTS IN NW MA AND SW NH WHERE
CHANGEOVER MAY NOT OCCUR TIL THU MORNING. OF COURSE SINCE WE ARE
STILL MORE THAN 48 HOURS FROM THE STORM THIS COULD CERTAINLY
CHANGE.

ICE WILL ALSO BE A CONCERN IN THE INTERIOR INCLUDING THE CT VALLEY
AS SFC COLD AIR MAY GET LOCKED IN AS THE CHANGEOVER OCCURS WITH
SEVERAL HOURS OF FREEZING RAIN POSSIBLE.

I would assume parts a the Merrimack Valley will have the same problem.

[Cambium]

Another very cool link to save... It shows you the precip type and amount that would fall based on the particular run of the model. Very easy to use and see.

http://coolwx.com/cgi-bin/getbufr.cgi?region=MA&stn=KBOS&model=nam&time=curr ent&field=prec

1. Scroll down and on the left pick your state
2. scroll down and on the left pick the station closet to you
3. scroll down and on the left pick the NAM or GFS

For instance... I'll show you 3 of them..

Latest GFS shows snow to rain to ice on the 27th for Windsor Locks. 1/2" of snow would mean about 3-5".



For White Plains NY the GFS shows snow to ice to rain on the 27th. Less than 1/2" worth of snow 2-3" before the rain




Here is Bridgeport... All rain. LOL. Over 2 inches of it on the 27th.

[Cambium]

**EURO TRENDED COLDER AND SOUTH MORE**

I didnt want to do this but I'll have to bring my laptop to the family party tonight just because.

Northern CT would stay all snow on this latest run. Snowmap to be posted when it updates.

Yesterdays 12z EURO update on left is over NYC. Todays 12z is over central NJ.
All of MA is below freezing at 850 with todays 12z. Was not yesterday. Northern CT as well.

[TobinJ]

Take your laptop to the family party? You would do that for us?! What a guy! Hip hip hooray for Cam! And a Happy Holidays too!

[7 Wishes]

The snowfall amounts map for tonight's "mini storm". That rain/snow line is right dead on the coast.....