Weather Wishcasting for 12/19

[castlerock]

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]

so what are we talking here? How much snow and when?

[gostan]

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]

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]

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]

I found the english translation for that article.

http://www.accuweather.com/blogs/new...95-weekend.asp

[skierdon]

pictures- now that's more like it! Looks like I may be taking a mid-week trip to Maine.

[Tin Woodsman]

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]

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]

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]

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]

so how will this affect/help the MRV- doesn't appear we will be anywhere near the eastern portion of the storm?

[HowieT2]

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]

not looking good for anyone this morning. need to burn more sacrifices to ullr.

[Treeskier]

I just heard they got a good additional inch this morning at the house. White every where!