Powerful Multi-regional/ multi-faceted east coastal storm now above medium confidence: Jan 29 -30th, MA to NE, with snow and mix combining high wind, and tides. Unusual early confidence ...

[mostman]

1 minute ago, Cmass495 said:

HIGHLIGHTS...

* WE NOW HAVE HIGH CONFIDENCE IN A HISTORIC MAJOR WINTER STORM FOR
 EASTERN NEW ENGLAND. WIDESPREAD 1 TO 2 FT SNOWFALL WITH LOCALIZED
 3 FT IS LIKELY FOR EASTERN MA AND RI ALONG WITH BLIZZARD
 CONDITIONS.
* SNOWFALL RATES COULD REACH 2 TO 4 INCHES PER HOUR AT TIMES DURING
 THE DAY ON SATURDAY WITH POSSIBILITY OF THUNDERSNOW ACROSS EASTERN
 MA AND RI.
* IN ADDITION TO POTENTIAL HISTORICAL SNOWFALL, STRONG WINDS UP TO
 HURRICANE FORCE ESPECIALLY ALONG THE COAST WILL LEAD TO BITTERLY
 COLD WIND CHILLS ON SATURDAY ALONG WITH MINOR TO MODERATE COASTAL
  FLOODING.   

DETAILS...

HEAVY SNOWFALL/EXTREME SNOWFALL RATES...

MODELS HAVE NOW COME INTO CONSENSUS FOR A HISTORICAL BLIZZARD TO
IMPACT EASTERN SOUTHERN NEW ENGLAND. EXPLOSIVE CYCLOGENESIS WILL
OCCUR OFF THE MID ATLANTIC COAST TONIGHT, WITH AN IMPRESSIVE 40 MB
PRESSURE DROP IN 24 HOURS AS A SURFACE LOW TRACKS FROM EAST OF THE
CAROLINAS TO THE 70W/40N BENCHMARK. FOR REFERENCE, A BOMB CYCLONE'S
CRITERIA IS A DROP OF 24 MB IN 24 HOURS. AT THIS POINT WITHIN 24
HOURS OF THE STORM, WE ARE NOW IN THE TIME FRAME WHERE THE NAM
GENERALLY PERFORMS WELL DURING AN EAST COAST CYCLOGENESIS EVENT.

WE NOW HAVE HIGH CONFIDENCE IN EXCEPTIONAL TO EXTREME SNOWFALL RATES   
WITH THE POSSIBILITY FOR THUNDERSNOW ACROSS EASTERN MA AND RI.   
SOMEWHAT LOWER CONFIDENCE IN THE EXACT PLACEMENT OF THE HEAVIEST   
BAND, HOWEVER. BOTH NAM AND GFS BUFKIT SOUNDINGS SHOW OVER 50 UNITS 

OF OMEGA COINCIDING WITH THE FAVORABLE SNOW GROWTH REGION. GIVEN   
THAT A DOUBLE BARREL LOW COULD DEVELOP WITH THE POTENTIAL FOR AN EYE-
LIKE FEATURE AT SOME POINT, WHEREVER THE MESOSCALE SNOW BAND SETS UP
COULD SEE 2 TO 4 INCHES PER HOUR SNOWFALL RATES WITH AN OUTSIDE
CHANCE FOR 5 INCHES PER HOUR ESPECIALLY WHEN ON THE BACKSIDE OF THE   
SYSTEM. IF A DEFORMATION BAND CAN PERSIST WHEN THE ARCTIC AIR
ARRIVES LATER IN THE DAY, SNOW TO LIQUID RATIOS (SLRS) COULD BE AS   
HIGH AS 20-25 TO 1. THEREFORE, WE FELT CONFIDENT ENOUGH IN THIS
FORECAST PACKAGE TO INTRODUCE AN AREA OF 24 TO 30 INCHES STORM TOTAL
SNOWFALL. IT IS POSSIBLE THAT THIS BAND COULD SET UP FURTHER WEST,
OR THERE MAY BE TWO BANDS OF HEAVY SNOW WITH LESSER AMOUNTS IN
BETWEEN. EITHER WAY, WE ARE CONFIDENT ENOUGH TO GO WITH A BLIZZARD
WARNING FOR THE POTENTIAL OF BLOWING AND DRIFTING SNOW WITH NEAR
ZERO VISIBILITY AT TIMES ACROSS MUCH OF EASTERN MA AND RI.

STRONG WINDS/BLOWING SNOW...  

WITH 925MB WINDS AT 65-70 KTS OR 4 TO 5 STANDARD DEVIATIONS ABOVE   
NORMAL ACCORDING TO GEFS AND NAEFS SITUATIONAL AWARENESS TABLE AND
COMBINED WITH EXCELLENT MIXING, THERE WILL BE HURRICANE FORCE WIND   
GUSTS AT TIMES ALONG THE IMMEDIATE COAST AND 50-60 MPH GUSTS FURTHER
INLAND. THIS WILL TRANSLATE TO WIDESPREAD DRIFTING AND BLOWING OF
SNOW WITH LOCALIZED SNOW DRIFTS OF UP TO 4 FT OR HIGHER. WITH
TEMPERATURES IN THE TEENS TO LOW 20S, WE HAVE HIGH CONFIDENCE IN
RATHER WIDESPREAD BLIZZARD CONDITIONS ACROSS EASTERN MA AND RI,
INCLUDING THE PROVIDENCE TO BOSTON CORRIDOR. BASED ON THE LATEST
GUIDANCE TRENDS, IT IS POSSIBLE THAT THE I-95 OR EVEN THE I-495 
CORRIDOR ENDS UP WITH A SECONDARY LOCAL SNOWFALL MAXIMA. THE SILVER
LINING IS THAT BECAUSE WE ARE DEALING WITH DRY POWDERY FLUFF, THERE
IS LESS OF A CONCERN FOR SNOW LOADING ISSUES EXCEPT FOR PARTS OF THE
OUTER CAPE AND NANTUCKET DUE TO THE COASTAL FRONT.

POWER OUTAGE POTENTIAL LOOKS TO BE HIGHEST ACROSS CAPE/ISLANDS,
WHERE THE WARMER TEMPS WOULD LEAD TO HEAVIER AND WETTER SNOW AND
CONSEQUENTLY HIGHER SNOW LOADING. WITH 70 MPH WINDS, POWER OUTAGES
WILL BE LIKELY.

THERE IS SOMEWHAT LOWER CONFIDENCE HOW FAR WEST THE HEAVY SNOW
OVERSPREADS AND THIS IS SOMETHING THAT WE CANNOT BE ENTIRELY SURE
UNTIL THE MESOSCALE BAND SETS UP AS THE STORM GETS GOING TOMORROW
MORNING. WHILE WE DO THINK THAT PLYMOUTH COUNTY IS STILL GOING TO
END UP WITH ONE OF THE HIGHEST TOTALS FOR THIS STORM, HOWEVER, THE 
SLRS MAY BE AFFECTED BY THE DENDRITIC GROWTH ZONE'S LESS THAN IDEAL
COINCIDENCE WITH THE BEST OMEGA RESULTING IN RIMING AND THE FACT
THAT THE HURRICANE FORCE GUSTS COULD BREAK UP DENDRITES.

Wonder how they feel about that GFS

[moneypitmike]

Well, the GFS never wanted to give us this storm anyway.......came west kicking and screaming.  Might have been right all along.

[OceanStWx]

2 minutes ago, ORH_wxman said:

GFS goes to George's Bank...lol

I mean I would hit that 700 low in a heartbeat. The GFS has all the best QPF east of its track. 

I'm tossing that run to Georges Bank with its surface low.

[kdxken]

Just now, The 4 Seasons said:

Final call. We kept our original forecast pretty much the same with amounts just tilted the axis of snowfall a bit to orient it more SW to NE. Tri-state area stayed very similar with the 12-20" range extending farther west across long island.

CT:

Tri-state:

CT warnings:

What about Massachusetts? Are we chopped liver or something?

[klw]

Q- are the models properly equipped to use the additional data collected from the recon flights if they are not usually part of the input?

Just curious.

Thanks, I will hang up and take my answer off the air..

[RUNNAWAYICEBERG]

Just now, HIPPYVALLEY said:

Every time.

Every storm off the east coast these days is affected by convection chasing. The only time that doesn't happen is when it stem winds up the Poconos. That's compact, no problem. 

[SouthCoastMA]

The GFS finally captures/consolitates at our latitude..but about 50 miles further east.

[MJO812]

[STILL N OF PIKE]

2 minutes ago, mostman said:

Wonder how they feel about that GFS

Wonder what storm that is even talking about 

[The 4 Seasons]

1 minute ago, kdxken said:

What about Massachusetts? Are we chopped liver or something?

get me a good CT/MA/RI base map and ill do it lol. We started with Connecticut but are expanding areas to include Tri-state NJ/CT/NY based on client needs. I'd definitely like to add a southern new england focused map next.

[TalcottWx]

Meteorology not Modelogy. Upper air. Mid-levels. I've never seen a solution do this with that setup. I just don't buy it. Stick to guns. 

[ice1972]

Always with the elongations…..

[wxeyeNH]

18Z GFS as compared to 12Z total QPF

[TauntonBlizzard2013]

I actually thought it initially looked better, and then chased that caca 

[EastonSN+]

[TalcottWx]

7 minutes ago, Cmass495 said:

HIGHLIGHTS...

* WE NOW HAVE HIGH CONFIDENCE IN A HISTORIC MAJOR WINTER STORM FOR
 EASTERN NEW ENGLAND. WIDESPREAD 1 TO 2 FT SNOWFALL WITH LOCALIZED
 3 FT IS LIKELY FOR EASTERN MA AND RI ALONG WITH BLIZZARD
 CONDITIONS.
* SNOWFALL RATES COULD REACH 2 TO 4 INCHES PER HOUR AT TIMES DURING
 THE DAY ON SATURDAY WITH POSSIBILITY OF THUNDERSNOW ACROSS EASTERN
 MA AND RI.
* IN ADDITION TO POTENTIAL HISTORICAL SNOWFALL, STRONG WINDS UP TO
 HURRICANE FORCE ESPECIALLY ALONG THE COAST WILL LEAD TO BITTERLY
 COLD WIND CHILLS ON SATURDAY ALONG WITH MINOR TO MODERATE COASTAL
  FLOODING.   

DETAILS...

HEAVY SNOWFALL/EXTREME SNOWFALL RATES...

MODELS HAVE NOW COME INTO CONSENSUS FOR A HISTORICAL BLIZZARD TO
IMPACT EASTERN SOUTHERN NEW ENGLAND. EXPLOSIVE CYCLOGENESIS WILL
OCCUR OFF THE MID ATLANTIC COAST TONIGHT, WITH AN IMPRESSIVE 40 MB
PRESSURE DROP IN 24 HOURS AS A SURFACE LOW TRACKS FROM EAST OF THE
CAROLINAS TO THE 70W/40N BENCHMARK. FOR REFERENCE, A BOMB CYCLONE'S
CRITERIA IS A DROP OF 24 MB IN 24 HOURS. AT THIS POINT WITHIN 24
HOURS OF THE STORM, WE ARE NOW IN THE TIME FRAME WHERE THE NAM
GENERALLY PERFORMS WELL DURING AN EAST COAST CYCLOGENESIS EVENT.

WE NOW HAVE HIGH CONFIDENCE IN EXCEPTIONAL TO EXTREME SNOWFALL RATES   
WITH THE POSSIBILITY FOR THUNDERSNOW ACROSS EASTERN MA AND RI.   
SOMEWHAT LOWER CONFIDENCE IN THE EXACT PLACEMENT OF THE HEAVIEST   
BAND, HOWEVER. BOTH NAM AND GFS BUFKIT SOUNDINGS SHOW OVER 50 UNITS 

OF OMEGA COINCIDING WITH THE FAVORABLE SNOW GROWTH REGION. GIVEN   
THAT A DOUBLE BARREL LOW COULD DEVELOP WITH THE POTENTIAL FOR AN EYE-
LIKE FEATURE AT SOME POINT, WHEREVER THE MESOSCALE SNOW BAND SETS UP
COULD SEE 2 TO 4 INCHES PER HOUR SNOWFALL RATES WITH AN OUTSIDE
CHANCE FOR 5 INCHES PER HOUR ESPECIALLY WHEN ON THE BACKSIDE OF THE   
SYSTEM. IF A DEFORMATION BAND CAN PERSIST WHEN THE ARCTIC AIR
ARRIVES LATER IN THE DAY, SNOW TO LIQUID RATIOS (SLRS) COULD BE AS   
HIGH AS 20-25 TO 1. THEREFORE, WE FELT CONFIDENT ENOUGH IN THIS
FORECAST PACKAGE TO INTRODUCE AN AREA OF 24 TO 30 INCHES STORM TOTAL
SNOWFALL. IT IS POSSIBLE THAT THIS BAND COULD SET UP FURTHER WEST,
OR THERE MAY BE TWO BANDS OF HEAVY SNOW WITH LESSER AMOUNTS IN
BETWEEN. EITHER WAY, WE ARE CONFIDENT ENOUGH TO GO WITH A BLIZZARD
WARNING FOR THE POTENTIAL OF BLOWING AND DRIFTING SNOW WITH NEAR
ZERO VISIBILITY AT TIMES ACROSS MUCH OF EASTERN MA AND RI.

STRONG WINDS/BLOWING SNOW...  

WITH 925MB WINDS AT 65-70 KTS OR 4 TO 5 STANDARD DEVIATIONS ABOVE   
NORMAL ACCORDING TO GEFS AND NAEFS SITUATIONAL AWARENESS TABLE AND
COMBINED WITH EXCELLENT MIXING, THERE WILL BE HURRICANE FORCE WIND   
GUSTS AT TIMES ALONG THE IMMEDIATE COAST AND 50-60 MPH GUSTS FURTHER
INLAND. THIS WILL TRANSLATE TO WIDESPREAD DRIFTING AND BLOWING OF
SNOW WITH LOCALIZED SNOW DRIFTS OF UP TO 4 FT OR HIGHER. WITH
TEMPERATURES IN THE TEENS TO LOW 20S, WE HAVE HIGH CONFIDENCE IN
RATHER WIDESPREAD BLIZZARD CONDITIONS ACROSS EASTERN MA AND RI,
INCLUDING THE PROVIDENCE TO BOSTON CORRIDOR. BASED ON THE LATEST
GUIDANCE TRENDS, IT IS POSSIBLE THAT THE I-95 OR EVEN THE I-495 
CORRIDOR ENDS UP WITH A SECONDARY LOCAL SNOWFALL MAXIMA. THE SILVER
LINING IS THAT BECAUSE WE ARE DEALING WITH DRY POWDERY FLUFF, THERE
IS LESS OF A CONCERN FOR SNOW LOADING ISSUES EXCEPT FOR PARTS OF THE
OUTER CAPE AND NANTUCKET DUE TO THE COASTAL FRONT.

POWER OUTAGE POTENTIAL LOOKS TO BE HIGHEST ACROSS CAPE/ISLANDS,
WHERE THE WARMER TEMPS WOULD LEAD TO HEAVIER AND WETTER SNOW AND
CONSEQUENTLY HIGHER SNOW LOADING. WITH 70 MPH WINDS, POWER OUTAGES
WILL BE LIKELY.

THERE IS SOMEWHAT LOWER CONFIDENCE HOW FAR WEST THE HEAVY SNOW
OVERSPREADS AND THIS IS SOMETHING THAT WE CANNOT BE ENTIRELY SURE
UNTIL THE MESOSCALE BAND SETS UP AS THE STORM GETS GOING TOMORROW
MORNING. WHILE WE DO THINK THAT PLYMOUTH COUNTY IS STILL GOING TO
END UP WITH ONE OF THE HIGHEST TOTALS FOR THIS STORM, HOWEVER, THE 
SLRS MAY BE AFFECTED BY THE DENDRITIC GROWTH ZONE'S LESS THAN IDEAL
COINCIDENCE WITH THE BEST OMEGA RESULTING IN RIMING AND THE FACT
THAT THE HURRICANE FORCE GUSTS COULD BREAK UP DENDRITES.

Amazing discussion. One for the books. 

[WxFreak11]

I wonder if NWS in Boston will do an adjustment on the snow totals map. 

[CoastalWx]

1 minute ago, DotRat_Wx said:

Amazing discussion. One for the books. 

It's like Kevin wrote it. Might be a wee bit over the top.

[CT Rain]

I love the enthusiasm... but that BOX AFD seems completely divorced from the reality of every piece of guidance today.

[Zeus]

3 minutes ago, DotRat_Wx said:

Meteorology not Modelogy. Upper air. Mid-levels. I've never seen a solution do this with that setup. I just don't buy it. Stick to guns. 

Sure, but the GFS half of our wager has swung solidly in my favor. Only a material boon from the Euro prevents you from buying me chickie nuggies and tall boy Gansetts.

[MegaMike]

15 minutes ago, klw said:

There is always the BTV local 4km WRF:

Mostly SE as well

https://www.weather.gov/btv/4kmwrf

Ignore it.

The configuration produces boundary issues which causes little-to-no precipitation along the boundary of predominant flow.

You can see it on the eastern side of the domain (a lot of QPF to basically none).

I sent them an email about it. When the server no longer works, it's not coming back.

[tiger_deF]

This is shaping to either be a complete bust for the models, of a complete bust for many snowfall maps

[SouthCoastMA]

Don't worry, there's still time for things to get worse. 

[TalcottWx]

Maybe they don't buy the strung out crap? 

[MarkO]

Just now, CT Rain said:

I love the enthusiasm... but that BOX AFD seems completely divorced from the reality of every piece of guidance today.

Ready to run my truck in the garage with the door shut. WTF happened? And yes, I want some of what they're smoking.

[SouthCoastMA]

32 minutes ago, SouthCoastMA said:

18z+Recap thus far

Absolute Shite : ICON/RGEM/GFS

OK 3K NAM/HRRR

Excellent: 12K NAM/RAP

Updated

[George001]

Gfs, rgem and all the other shitty models that rob the convection tossed imo. They are all east of the Navy, and obs indicate the low is deepening faster than expected. TV Mets still have my area getting 18-24 and some have my area getting 24+. 

[OceanStWx]

2 minutes ago, tiger_deF said:

This is shaping to either be a complete bust for the models, of a complete bust for many snowfall maps

As I get crustier I'm more convinced than ever that we (NWS) shouldn't entertain 24+ in our forecasts until we see the whites in the eyes of a band. It gets forecasts into trouble more often than not. 

We always seem to chase the peak runs in the 48-24 hour window and inevitably have to back off inside that in most areas. 

I think the last 72 hours at least have been pretty consistent from an ensemble perspective, despite what individual members/models had.

[PhineasC]

Hanging by a NAM thread. If Euro bumps east seems safe to say the huge totals are probably off the table. 

[mostman]

Inside 12 hours until formation and BOX is straight up tossing the models. Bold. Will be interesting to see how this pans out.