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castlerock
12-16-2010, 05:18 AM
From the BTV Discussion, 647 AM EST THU DEC 16 2010

MODEL ANALYSIS: FOR DAYS 4 THRU 7 WL CONT TO USE AN ENSEMBLE
APPROACH WHICH WOULD SUPPORT MENTIONING CHC POPS SUNDAY INTO
MONDAY...BUT GIVEN NO TRENDS HAVE BEEN ESTABLISHED WITH SFC LOW
PRES TRACK AND DEVELOPMENT OF MID/UPPER LVL FEATURES OVERALL
CONFIDENCE IS VERY LOW. THE 12Z GFS SHOWED SOUTHERN/NORTHERN
STREAM INTERACTION AND DEVELOPMENT OF A SIGNIFICANT COASTAL LOW
PRES NEAR CAPE COD ON SUNDAY....WITH CLOSED MID/UPPER LVL
CIRCULATION CAPTURING THE SYSTEM. IN ADDITION...THE 12Z GFS
ENSEMBLE PRECIP PLUMES SHOWED A HUGE SPREAD WITH LIMITED
CLUSTERING FROM SOME MEMBERS INDICATING NO PRECIP TO OTHERS
SUGGESTING OVER 2.0" OF QPF WOULD BE POSSIBLE AT BTV. THE 18Z GFS
SHOWED A FURTHER EAST TRACK WITH NO IMPACT TO OUR CWA...WHILE THE
ENSEMBLE DATA CONTINUED TO SHOW A LARGE SPREAD FROM QPF <0.25" TO
AMOUNTS >1.50". MEANWHILE...THE 00Z GFS HAS SHIFTED WELL SOUTH AND
EAST OF THE 40/70 BENCHMARK AND SHOWS A MUCH FLATTER AND LESS
AMPLIFIED SYSTEM WITH LIMITED JET STREAM INTERACTION. THIS
SOLUTION IS ALSO SUPPORTED BY THE 00Z GEM AND 00Z UKMET. IN
ADDITION...THE 00Z GFS ENSEMBLE DATA HAS SHIFTED TO THE EAST...BUT
CONTS TO SHOW A 12 TO 14MB SPREAD TWD THE WEST IN ITS MSLP FIELDS.
THESE SOLUTIONS WOULD HAVE LIMITED IMPACT TO OUR CWA AND SEEM
REASONABLE GIVEN THE GREATER CLUSTERING OF GUIDANCE TO THE SOUTH
AND EAST OF THE BENCHMARK.

HOWEVER...JUST REVIEWED THE 00Z ECMWF...WHICH TYPICALLY HANDLES
MED RANGE FCSTS THE BEST AND PERFORMS BETTER IN HIGHLY AMPLIFIED
PATTERNS. THIS SHOWS POTENT SOUTHERN STREAM INTERACTING WITH
NORTHERN STREAM ENERGY AND FORMING SFC LOW PRES OFF THE HATTERAS
COAST ON SATURDAY NIGHT. SFC LOW IS PROGGED TO TRACK NORTH AND BE
CAPTURED BY DEVELOPING AND CLOSING OFF MID/UPPER LVL CIRCULATION
OVER THE MID ATLANTIC STATES ON SUNDAY AND PLACES A 978MB LOW PRES
NEAR CAPE COD BY 06Z MONDAY. THE SFC LOW PRES IS PULLED INTO THE
GULF OF MAINE...THEN RE-CURVES OUT TO SEA BY 12Z TUES. THIS IS VERY
SIMILAR TO THE 12Z GFS SOLUTION AND 00Z 12/15/10 UKMET
SOLUTIONS...AND REMAINS ME OF THE JAN 1-3 STORM OF 2010. THIS
WOULD PLACE BACKSIDE DEFORMATION BAND WITH GOOD DEEP LAYER
MOISTURE ADVECTION FROM THE ATLANTIC ACRS OUR REGION...WITH A
PLOWABLE SNOW FOR THE CPV AND POINTS EAST. HOWEVER...BEFORE
INCREASING POPS AND GETTING INTO GREATER DETAILS...I WOULD LIKE
TO SEE SOME RUN TO RUN CONSISTENCY...ALONG WITH SOME TRENDS EITHER
WEST OR EAST IN THE GUIDANCE. FOR NOW...WL JUST MENTION CHC POPS
SUNDAY INTO MONDAY FOR SNOW.

skierdon
12-16-2010, 07:19 AM
so what are we talking here? How much snow and when?

gostan
12-16-2010, 08:01 AM
so what are we talking here? How much snow and when?Unfortunately, I think that the question is: "How much snow on Cape Cod and when?"

random_ski_guy
12-16-2010, 08:04 AM
Someone probably knows bettre, but I think 2 inches of precip is generally associated with 18-24 inches of snow....depending on how "dry" the snow is when it falls.

Hardbooter
12-16-2010, 08:34 AM
That seems more like the crappy driving forecast than the ski forecast. I guess we'll see.

BTW, does google have a weather-nerd to english translator?

Hardbooter
12-16-2010, 09:19 AM
I found the english translation for that article.

http://www.accuweather.com/blogs/news/story/43076/odds-increase-for-i95-weekend.asp

http://vortex.accuweather.com/adc2004/pub/includes/columns/newsstory/2010/400x266_12152037_weekendstormrisk.jpg

skierdon
12-16-2010, 09:31 AM
pictures- now that's more like it! Looks like I may be taking a mid-week trip to Maine.

Tin Woodsman
12-16-2010, 09:33 AM
HOWEVER...JUST REVIEWED THE 00Z ECMWF...WHICH TYPICALLY HANDLES
MED RANGE FCSTS THE BEST AND PERFORMS BETTER IN HIGHLY AMPLIFIED
PATTERNS. THIS SHOWS POTENT SOUTHERN STREAM INTERACTING WITH
NORTHERN STREAM ENERGY AND FORMING SFC LOW PRES OFF THE HATTERAS
COAST ON SATURDAY NIGHT. SFC LOW IS PROGGED TO TRACK NORTH AND BE
CAPTURED BY DEVELOPING AND CLOSING OFF MID/UPPER LVL CIRCULATION
OVER THE MID ATLANTIC STATES ON SUNDAY AND PLACES A 978MB LOW PRES
NEAR CAPE COD BY 06Z MONDAY. THE SFC LOW PRES IS PULLED INTO THE
GULF OF MAINE...THEN RE-CURVES OUT TO SEA BY 12Z TUES. THIS IS VERY
SIMILAR TO THE 12Z GFS SOLUTION AND 00Z 12/15/10 UKMET
SOLUTIONS...AND REMAINS ME OF THE JAN 1-3 STORM OF 2010. THIS
WOULD PLACE BACKSIDE DEFORMATION BAND WITH GOOD DEEP LAYER
MOISTURE ADVECTION FROM THE ATLANTIC ACRS OUR REGION...WITH A
PLOWABLE SNOW FOR THE CPV AND POINTS EAST.


This is the money quote. If you get a deformation band settling in across the region, you're almost guaranteed to get a solid 8-12", though perhaps not as much as points East. Still, enough to get upper/mid mountain natural runs runs like Paradise, Domino, Black Diamond, Upper Lookin Good and Bravo on the cusp of opening, if not all the way there.

Hardbooter
12-16-2010, 09:43 AM
If you get a deformation band settling in across the region, you're almost guaranteed to get a solid 8-12", though perhaps not as much as points East.

I think that's a real long shot. All the weather nerds at accuweather (and they've got lots) are debating whether it tracks like the picture above or goes directly out to sea off of new jersey. The question is whether the warm, wet air can make a dent in the cold, dry stuff that's here now to produce the picture. At accuweather they don't say anything about a secondary low or anything.

Not that I won't be happy to ski it if it comes...

HowieT2
12-16-2010, 10:37 AM
anyone know what the latest models show? the americanwx.com board is down for a server upgrade.
The GFS has been showing this storm for some time albeit south and east of where we want it. The euro had not, but evidently amplified the southern stream on last night's run which is what the gfs had prior. This is a good sign.

HowieT2
12-16-2010, 11:42 AM
I'm starting to get a wee bit excited.

AS OF 330 PM EST THURSDAY...GFS AND ECMWF HAVE COME MORE INTO
LINE WITH REGARDS TO THE EXTENDED PORTION OF THE
FORECAST...PROVIDING BETTER FORECASTER CONFIDENCE FOR THE DAYS 4
THROUGH 7 PORTION OF THE FORECAST. THESE RUNS ARE ALSO IN
AGREEMENT WITH 00Z ECMWF. WILL CONTINUE TO MONITOR FOR MORE RUN-
TO-RUN AND MODEL-TO-MODEL CONSISTENCY IN FUTURE MODEL RUNS.

THE EXTENDED PORTION OF THE FORECAST BEGINS SUNDAY WITH A LARGE
SCALE MID/UPPER LEVEL TROF CONTINUING TO RETROGRADE WEST ACROSS
SOUTHERN CANADA FROM NORTHERN ONTARIO BACK WESTWARD INTO MANITOBA
THEN AND THEN INTO SASKATCHEWAN BY EARLY MONDAY MORNING. THIS
WILL MAKE WAY FOR VERTICALLY STACKED LOW PRESSURE SYSTEM WHICH
WILL FORM AND THEN DEEPEN OFF THE COAST OF CAPE HATTERAS NORTH
CAROLINA ON SUNDAY MORNING. DURING THE DAY SUNDAY THIS LOW WILL
LIFT NORTH AND END UP JUST SOUTH OF LONG ISLAND BY SUNDAY NIGHT.
THE LOW WILL VERY SLOWLY TRACK NORTHEAST TOWARDS CAPE COD
OVERNIGHT. THE LOW WILL BE NEARLY STATIONARY THROUGH THE DAY
MONDAY...THEN SLOWLY SLIDE EAST AND AWAY FROM THE NEW ENGLAND
COAST MONDAY NIGHT INTO TUESDAY.

HAVE PLACED LIKELY POPS IN THE FORECAST FOR SUNDAY NIGHT AND
MONDAY FOR ROUGHLY THE EASTERN HALF OF OUR FORECAST AREA. COULD
BE A PROLONGED PRECIPITATION EVENT WITH PRECIPITATION STARTING AS
EARLY AS SUNDAY EVENING AND CONTINUING THROUGH AT LEAST TUESDAY.
MOISTURE ADVECTION FROM THE ATLANTIC WILL BE IN PLACE ACROSS OUR
REGION.

skierdon
12-16-2010, 11:43 AM
so how will this affect/help the MRV- doesn't appear we will be anywhere near the eastern portion of the storm?

HowieT2
12-16-2010, 11:50 AM
so how will this affect/help the MRV- doesn't appear we will be anywhere near the eastern portion of the storm?

I think we are in the eastern portion of the forecast area which extends into nrthn NY/adk. they upped the POPs for warren to 60%. my understanding is the ideal track would be over the CC canal. right now it is projected to go over CC.

Benski
12-17-2010, 04:00 AM
not looking good for anyone this morning. need to burn more sacrifices to ullr.

Treeskier
12-17-2010, 04:32 AM
I just heard they got a good additional inch this morning at the house. White every where!

gratefulskier
12-17-2010, 04:50 AM
Yesterday morning, the storm sounded like a complete miss.

By the evening, it was sounding better.

This morning, it is sounding more pessimistic, based on the "40N 70W benchmark". See this blog post for more info about the benchmark:

http://blogs.middlebury.edu/middland/2009/03/03/forecasting-a-noreaster/

The good thing is that all the forecasts remain fairly low confidence, so things can certainly change.


GS

HowieT2
12-17-2010, 05:52 AM
Keep hope alive! from BTV

MODELS CONT TO STRUGGLE WITH INITIALIZATION OF POTENT S/W ENERGY
NEAR THE HUDSON BAY...AND SEVERAL EMBEDDED VORTS EJECTING FROM
DEEP CYCLONIC CIRCULATION OVER THE PACIFIC NORTHWEST. BASED ON UA
DATA AND WATER VAPOR TRENDS...POTENT DISTURBANCE NEAR HUDSON BAY
WAS POORLY SAMPLED IN THE 00Z DATA...AND THEREFORE IS TOO WEAK IN
THE MODELS. MEANWHILE...THE EMBEDDED VORT IN THE FAST WESTERLY FLW
ALOFT ACRS THE WESTERN CONUS IS COMING ASHORE AND STARTING TO GET
CAPTURED BY UA DATA. THIS FEATURE...ALONG WITH THE 130 KNT JET AT
25H SEEMED TO INITIALIZE BETTER IN THE MODELS. STILL FEELING A
STRONG NORTHERN STREAM DISTURBANCE WL HELP DEEPEN/CLOSED MID/UPPER
LVL TROF ACRS THE EASTERN CONUS QUICKER/SOONER AND CAPTURE SFC LOW
PRES DEVELOPING OFF THE CAROLINA COAST LATE SUNDAY AND TRACK THE
SYSTEM FURTHER WEST TWD THE COAST. FURTHERMORE...I STILL HAVE DIFFICULTIES
WITH PLACEMENT OF SFC LOW PRES SO FAR EAST IN RELATION TO 25H JET
COUPLET AND 5H PVA ASSOCIATED WITH DIGGING NORTHERN STREAM TROF. BASIC
METEOROLOGY WOULD SUPPORT A SOLUTION CLOSER TO THE COAST...WITH RAPID
INTENSIFICATION OF SFC CYCLONE DUE TO POTENT ENERGY ALOFT AND VERY
WARM GULF STREAM WATERS...WHICH WL HELP TO SETUP A TIGHT
BAROCLINIC ZONE JUST OFF SHORE. FEEL THE RAPID
INTENSIFICATION...WHICH MODELS STRUGGLE TO CAPTURE...AND BETTER
PHASING OF NORTHERN/SOUTHERN STREAM SYSTEMS SUGGESTED BY THE 12Z
DATA SEEMS REASONABLE AT THIS TIME AND WL TREND TWD IN THE FCST.
THIS WOULD SUPPORT AT LEAST HIGH CHC/LOW LIKELY POPS FOR SUNDAY
NIGHT INTO MONDAY...ALONG WITH INCREASE CONFIDENCE FOR A PLOWABLE
SNOWFALL FOR PARTS OF CENTRAL/EASTERN VT.

BY LATE MONDAY INTO TUESDAY...STRONG BLOCKING ACRS GREENLAND
ASSOCIATED WITH A STRONGLY NEGATIVE NAO WL HELP TO RETROGRADE SFC
LOW PRES BACK TWD THE GULF OF MAINE. IN ADDITION...DEEP CLOSED
MID/UPPER LVL TROF ACRS SNE WL BECM NEGATIVELY TILTED AND HELP
TRACK SFC LOW PRES BACK TO THE WEST TWD THE GULF OF MAINE. THIS
SOLUTION IS SUPPORTED BY THE 00Z ECMWF...00Z GFS...AND 00Z GEM AND
WOULD PRODUCE MORE WRAP AROUND MOISTURE AND SNOW FOR PARTS OF OUR
REGION. IN ADDITION...MID LVL WAA WOULD DEVELOP AND HELP TO
ENHANCE LIFT ACRS OUR NORTHERN/CENTRAL CWA. WL CONT TO MENTION
HIGH CHC POPS ATTM...BUT THIS WL NEED TO BE WATCHED CLOSELY.

OVERALL PLENTY OF UNCERTAINTY WITH DAYS 4 THRU 7 WITH LITTLE RUN
TO RUN CONSISTENCY MAKING FOR AN EXTREMELY DIFFICULT FCST.
HOWEVER...TRENDS ARE SUGGESTING AN INCREASE POTENTIAL FOR AT LEAST
SOME SNOW ACRS CENTRAL/EASTERN VT BY LATE THIS WEEKEND/EARLY NEXT
WEEK. TEMPS WL BE MAINLY IN THE 20S FOR HIGHS AND TEENS/20S FOR
NIGHTTIME LOWS. LITTLE DIURNAL CHANGE ANTICIPATED DUE TO
CLOUDS/PRECIP.

ahm
12-17-2010, 06:28 AM
BUT WITH THE APPROACHING UPPER TROUGH...SURFACE LOW PRESSURE
DEVELOPS AND TRACKS UP THE EAST COAST. COMPUTER MODELS ARE IN
GENERAL AGREEMENT THAT THIS FEATURE WILL TRACK OFFSHORE OF NEW
ENGLAND... A FAVORABLE TRACK FOR SNOWFALL. HOWEVER...JUST HOW FAR
OFFSHORE IT TRACKS WILL DETERMINE WHETHER NORTHERN NEW ENGLAND
GETS SIGNIFICANT SNOWFALL OR ONLY GETS BRUSHED WITH A FEW FLAKES.
GENERALLY EXPECT SNOWFALL TO BE MOST LIKELY ALONG THE COASTAL
SECTIONS ON SUNDAY NIGHT AND MONDAY...CLOSER TO THE TRACK OF THE
LOW. ACCUMULATIONS LOOK TO BE LIGHT TO MODERATE...WITH THE
HEAVIEST AMOUNTS OCCURRING NEAR THE COAST. AS THE UPPER LOW GETS
CUT OFF AND BECOMES STATIONARY OVER THE REGION...IT WILL PULL THE
SURFACE LOW BACK TO THE NORTH AND WEST TOWARD THE COAST. IN
ADDITION...WARM AND MOIST AIR IS EXPECTED TO WRAP IN AND AROUND
THE LOW MONDAY NIGHT...HELPING TO INCREASE PRECIPITATION
INTENSITY. THE HEAVIEST SNOW MAY ACTUALLY FALL DURING THIS TIME
PERIOD...THOUGH IT IS UNCLEAR WHETHER ENOUGH WARM AIR WILL WRAP
AROUND TO ALTER THE PRECIPITATION TYPE FROM SNOW TO RAIN
ESPECIALLY ALONG THE MIDCOAST. SNOWFALL TOTALS ARE STILL VERY
DEPENDENT ON THE TRACK OF THE LOW...THE AMOUNT OF MOISTURE
AVAILABLE...AND WHETHER TEMPERATURES STAY COLD ENOUGH FOR SNOW FOR
THE DURATION OF THE PRECIPITATION. THERE IS A POTENTIAL FOR
SIGNIFICANT ACCUMULATIONS BOTH ON SUNDAY NIGHT WITH THE INITIAL
PASSING OF THE LOW...AND ON MONDAY NIGHT AS MORE MOISTURE WRAPS
AROUND TOWARD THE COAST.

SNOW GENERALLY COMES TO AN END ON TUESDAY AS LOW PRESSURE MOVES
OFF TO THE EAST...AND A SURFACE TROUGH DROPS SOUTH ACROSS THE

Hopefully this "Holiday Gift" comes to a nice spot under our collective trees................

AHM