Back to Back Snowstorms East U.S Jan 2015 (icy, most, map)

[Cambium]

My final look at the latest snow total forecast pieced together from multiple offices.

Unless something drastic changes I wont be doing this again for this storm.

Nice little snowstorm going to happen. To bad a lot of it will be washing away....

[Cambium]

Radar & 850mb temp update.

There's a tounge of warm air over central NJ already. Yikes!

Mixing happening in Baltimore right now. This is NOT an image I'd like to see. That warm air is filtering in quick.

Should hold for CT until sunrise. Also as precip moves in should keep the column cool.

Snow starts after midnight here. Most will be sleeping during the highest accumulations.

[Cambium]

Check out Earths Winds! Tell me how the flow is

https://www.windyty.com/?850h,wind,now,42.488,-70.488,4

I'm not a fan of that High pressure right there! Enough with the warm air infiltration!

[Cambium]

HRRR HiRes short term model snowfall total till 11am

Hmmmm. I'm in the 7-9" zone.

https://twitter.com/RaleighWx/status...375041/photo/1

[Cambium]

Started snowing here 12:30am. Already sticking with 0.10" accumulation

SPC outlines Heavy Snow Discussion. Gets technical

CONCERNING...HEAVY SNOW

VALID 240448Z - 241045Z

SUMMARY...HEAVY SNOW WILL BE DEVELOPING OVERNIGHT TONIGHT --
ESPECIALLY FROM 06Z TO 09Z -- FROM PORTIONS OF THE CNTRL
APPALACHIANS ENEWD TO SRN NEW ENGLAND AND THE LONG ISLAND
COAST...INCLUDING THE NEW YORK CITY METROPOLITAN AREA. LOCAL
SNOWFALL RATES TO 1 INCH PER HOUR WILL BE POSSIBLE.

DISCUSSION...MOSAIC RADAR IMAGERY INDICATES A SHIELD OF WIDESPREAD
PRECIPITATION EXTENDING FROM THE MID-ATLANTIC TO THE OHIO
VALLEY...EMBEDDED WITHIN A BROAD WARM-ADVECTION ZONE ANALYZED AT
H85. THIS PRECIPITATION WILL CONTINUE TO SPREAD ENEWD THROUGH THE
NIGHT...AS RELATED ISENTROPIC ASCENT IS MAINTAINED WELL DOWNSTREAM
OF A POSITIVELY TILTED MIDLEVEL TROUGH...WHICH WATER VAPOR LOOPS
DEPICT AS EXTENDING FROM THE MIDDLE OH VALLEY TO THE LOWER MS
VALLEY. RECENT SFC OBSERVATIONS SUGGEST 2-HOURLY PRESSURE FALLS
AROUND 3.5-4.5 MB FROM SERN VA TO ERN NC...MOST LIKELY A REFLECTION
OF INCREASING LARGE-SCALE ASCENT PRECEDING THE TROUGH BECOMING
JUXTAPOSED WITH A NE/SW-ORIENTED BAROCLINIC ZONE/INVERTED TROUGH
ANALYZED ROUGHLY 40-75 MILES INLAND FROM THE COAST. SFC LOW PRESSURE
IS FORECAST TO CONSOLIDATE/DEEPEN FROM THIS INTERACTION AND MOVE OFF
THE COAST...WITH A CORRESPONDING INCREASE IN WAA AND FRONTOGENETIC
ASCENT TO ITS N. IN TURN...PRESENT PRECIPITATION INTENSITY WILL BE
MAINTAINED...OR PERHAPS INCREASE...ACROSS THE DISCUSSION
AREA...PARTICULARLY AS A DEFORMATION BAND BECOMES ESTABLISHED WELL
N/NW OF THE EVOLVING SFC CYCLONE.

SUBJECTIVE SPATIAL INTERPOLATION BETWEEN THE 00Z IAD AND OKX RAOBS
SUGGESTS NEAR- TO BELOW-FREEZING TEMPERATURES EXISTING...AND
CONTINUING TO EXIST...THROUGHOUT THE TROPOSPHERE ACROSS THE MCD
AREA. THIS IS ESPECIALLY THE CASE GIVEN CONTINUED NOCTURNAL DIABATIC
COOLING AND MODEST ADIABATIC COOLING ASSOCIATED WITH DCVA PRECEDING
THE APPROACHING MIDLEVEL TROUGH. WHERE SFC TEMPERATURES REMAIN
SLIGHTLY ABOVE 0C FROM SERN PA TO CNTRL NJ...WET-BULB-ZERO HEIGHTS
WILL GENERALLY REMAIN AOB 500 FT AGL -- AS AFFIRMED BY RAP FORECAST
SOUNDINGS AND INTERPOLATED OBSERVED SOUNDINGS. AS SUCH...SNOW IS
FORECAST TO BE THE PREDOMINANT PRECIPITATION TYPE ACROSS THE
DISCUSSION AREA...WITH DEEP...NEAR-ISOTHERMAL/NEAR-0-C LAYERS
FOSTERING EFFICIENT GROWTH OF SNOW AGGREGATES. AS SUCH...SNOWFALL
RATES WILL LOCALLY REACH 1 INCH PER HOUR. SUCH RATES IN HEAVY SNOW
WILL LIKELY MATERIALIZE BETWEEN 06Z AND 09Z FROM CNTRL PA TO CNTRL
NJ...WHILE SPREADING ENEWD TOWARD THE NEW YORK CITY AREA AND SRN NEW
ENGLAND THROUGH THE LATE-NIGHT HOURS.

VERY LATE TONIGHT...GENERALLY AFTER 10Z...IT IS POSSIBLE THAT
STRENGTHENING ONSHORE FLOW ALONG THE E-CNTRL NJ COAST -- IN RESPONSE
TO CYCLOGENESIS FARTHER SOUTH -- MAY SUPPORT SUFFICIENT LOW-LEVEL
WARMING FOR PRECIPITATION TO MIX WITH AND/OR CHANGE TO RAIN.
HOWEVER...THIS WILL GENERALLY BE IN A CONFINED AREA NEAR THE COAST
WHERE OCEANIC HEAT FLUXES ARE MAINTAINED INLAND ONLY OVER A MODEST
DISPLACEMENT.

[Cambium]

5:00am.. 4.8" total so far. 1.3" in last hour. Pines getting weighed down, clumps falling off.. About 8:1-9:1 snow ratios. Heavy Snow rates in last 2 hrs. Went from 2.25" at 3am to almost 5" 2 hrs later. Winds calm. The Silence of the night with snow falling.

[Cambium]

Here it comes... Raining on Long Island. Couple more hours should do it for coastal CT. Still snowing in NYC 5:15am

[Cambium]

This map makes it so clear why the 850mb level temps is so important for snow. If its above freezing, forget snow. Look where the freezing line is.

NYC about to or is changing over at this very moment. This is why Long island is rain and CT is snow right now.

RUC model might be a bit too far with the freezing line near White Plains but it's close! Mid Levels are warming up!

[Cambium]

THUNDERSNOW!!! That was INSANE. Brightest blue flash and a little pop. I thought was a transformer but others miles away saw it too so it was Thundersnow. This is insane.

6:00am. 6.0" Snow total. 1.2" in last hour. Rates are amazing!

[Cambium]

Record daily snowfall:

JFK: 3.4" (2.8" in 1971)
BDR: 5.5" (1.7" in 1965)
EWR: 5.1" (4.8" in 1948)
ISP: 3.1" (0.1" in 2005)

Snowfall total reports for CT only from the 3 WFO's. Burlington & New Britain in Hartford County with 8".