674 replies to this topic

[LongIslandCoastalWx]

I am starting this thread because I see some discussion on this potential in the other thread, which is meant for the early week storm. So I'd like to keep the discussions separate. Thanks guys.

[weatherman1]

look at all the moisture this storm will be working with

[forte408]

The end of this month may very well deliver the biggest blockbuster hit of the year. And that's saying A LOT in this winter.

[TatamyPA]

2/13 0z Euro at 216 hrs



12z Euro at 192 hrs



12 Euro at 216 hrs



FWIW - the GFS does not show this event happening at all - today's runs have all shown a strongly suppressed scenario.

The 18z DGEX shows a suppressed scenario with the system moving east OTS off of VA.

The 18z GFS ensembles have only 3 members showing the storm - all suppressed.

At this point in time there is still plenty of time for the models to find this storm

[IdolikesnowKocin]

weatherman1, on Feb 13 2010, 04:44 PM, said:

look at all the moisture this storm will be working with

My only realistic fear is that so much energy coming from the south will cause mixing issues/ rain for the immediate coast

[TatamyPA]

Latest HPC Longe Range Discussion - Looks like the HPC guys are liking the Euro scenario for next weekend too.

EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
108 PM EST SAT FEB 13 2010

VALID 12Z TUE FEB 16 2010 - 12Z SAT FEB 20 2010

INTENSE POSITIVE HT ANOMALIES CONT THRU THIS PERIOD NEAR CAPE
FAREWELL AND OVER THE SERN AK PANHANDLE KEEPING UP THE STRONG
PERSISTENT NEG AO/NAO PATTERN. REASONABLE MODEL AGREEMENT
CONTINUES THRU DAY 5 THURSDAY OF A NEAR NEUTRAL TO SLIGHTLY
POSITVE PNA PATTERN BY GFS AND GFS ENS GUIDANCE. DIFFERENCES SHOW
UP BY DAY 6 FRIDAY ONWARD AS GFS AND ITS ENS MEAN TO SOME EXTENT
UNDER CUT THE WRN CONUS COASTAL RIDGING RESULTING IN A NERN
PACIFIC REX BLOCK WITH CONSIDERABLE SRN STREAM FLOW COMING ACROSS
THE SRN TIER OF CONUS. IN THIS STRONG EL NINO YEAR THIS REMAINS
POSSIBLE. CURRENT MJO PHASE 8 AND ENTERING PHASE 1 WHILE WEAKENING
INTO INDETERMINATE STATUS LEAVES A RELATIVELY POOR MATCH TO D+8
GUIDANCE OF GFS OR ECMWF. THESE DIFFER LATE PERIOD AND INTO THE
DAY 8 AND BEYOND BY GFS KEEPING UP A STRONGER SRN STREAM AS
MENTIONED PREVIOUSLY WHILE BOTH MODELS AND CMC KEEP UP THE STRONG
POSITIVE HT ANOMALIES NEAR LOWER DAVIS STRAIT AND THE SRN AK
PENINSULA. ECMWF KEEPS UP MUCH MORE OF A STRONGER DOMINANT
AMPLIFIED PNA PATTERN. D+8 ANALOGS OF GFS/ECMWF/CMC LIKE FEB 63
AND 68 BOTH OF WHICH HAD A VERY AMPLIFIED PNA PATTERN AND A SRN
STREAM CONNECTION AT THE ANALOG TIME FRAME..A HYBRID OF THE TWO
MODEL SOLUTIONS LATE PERIOD. HOWEVER THESE WERE BOTH NON EL NINO
YEARS. GOING A BIT FARTHER TO THE D+11 TIME FRAME GFS/CMC SERIES
TARGET AND HAVE BEEN TARGETING FOR QUITE A WHILE FEB 1978 AND
ESPECIALLY FEB 1958 WHICH WERE INFAMOUS ERN CONUS WINTERS AND WERE
WARM ENSO EL NINO YEARS LIKE TEH CURRENT ONE. THE INFLUENCE OF THE
STRONG NEG A0/NAO AND ITS CORRESPONDING PARTNER THE POSITIVE PNA
HAS BEEN THE LEADING INFLUENCE OVER NOAM THIS WINTER WITH A VERY
SIGNIFICANT MOISTURE FEED FROM THE SRN STREAM. PREFER THE
AMPLIFIED ECMWF ENS MEAN WITH SOME ADDITION OF THE GFS ENS MEAN
WHICH IS MORE AMPLIFIED THAN ITS OP RUN FOR DAYS 6 AND 7 FRI/SAT
WITH THIS BEING THE PREVAILING PATTERN.

HPC PRELIMS 50/50 OP ECMWF/GFS DAYS 3 AND 4 TUES/WED WITH
INCREASING INCORPORATION OF ENS MEANS DOMINATED BY ECMWF ENS MEAN
DAYS 5-7 THURS-SAT.
NO CHANGES TO AFTN FINALS. 12Z OP MODELS HAVE ENOUGH ILL AGREED
UPON CHANGES FROM PRIOR RUNS AND AMONG THEMSELVES TO STAY WITH AN
ENS BASED SOLUTION.
MID LEVEL CLOSED LOW AND SFC REFLECTION SWINGS OFF THE NORTHEAST
COAST DAY 3 TUES ROTATING UP TO THE ST LAWRENCE RIVER VALLEY WHERE
IT BECOMES A LOCKED IN FEATURE. THIS SPREADS A MODERATE SNOW
ACROSS ERN PA/NJ/NY INTO NEW ENG WITH CONTINUOUS COLD ADVECTION
FLOW AND WELL BELOW NORMAL TEMPS OVER THE ERN THIRD OF CONUS WITH
LAKE EFFECT SNOWS AND UP SLOPE SNOWS INTO THE NRN AND CENTRAL
APPLCHNS INTO DAY 5 THURSDAY. SHORTWAVE ENERGY COMING ACROSS THE
SOUTHWEST AND SRN PLAINS FRI AND SAT WITH A ECMWF/ECMWF ENS MEAN
PREFERENCE BREAKS OUT TX TO TN VALLEY PCPN THE NRN PORTION OF
WHICH WILL NEED TO BE CLOSELY WATCHED FOR WINTER TYPE PCPN. THIS
WILL SPREAD EWD INTO MUCH OF ERN CONUS DAY 8 SUNDAY.

WESTWARD WET CONDS WELL AGREED UPON NRN CA AND PAC NORTHWEST INTO
THE NRN ROCKIES DAY 3 TUES WITH ROCKIES SNOWS WED AND THURS.
PREFER THE DRIER PATTERN OF ECMWF/ECMWF ENS MEAN OVER THE WEST
COAST LATE PERIOD. HIGH PRESSURE DROPS SOUTHWARD THRU THE PLAINS
WED TO SAT REINFORCING SEASONABLY COLD WEATHER.
ROSENSTEIN

[TatamyPA]

[quote name='IdolikesnowKocin' date='Feb 13 2010, 06:46 PM' post='144622']
Mt only realistic fear is that so much energy coming from the south will cause mixing issues/ rain for the immediate coast

Pay attention to the Euro for now - none of the other models have picked up on this storm. All we know is that the Euro has had it for two straight runs now. This event has appeared a couple of times on the GFS - but only for one run and then it goes away again. On today's runs the GFS has had it down near Florida. There's plenty of time for the other models to pick up on this and hone in on what the outcome will be. As for mixing/rain - too soon to tell.

[jackfrost77]

Your worried about mixing a week away??? Might as well put up snowfall maps while your at it.

[LongIslandCoastalWx]

00Z GFS loses the storm possibility.

[LongIslandCoastalWx]

00Z GGEM

168



192

[TatamyPA]

This storm is a no show on the 0z/6z GFS. The Euro shows a weak system exiting the NC coast which moves ENE OTS and bombs out over the fish. 06z DGEX shows a weak impulse exiting the MD coast.

[TatamyPA]

Latest HPC Extended Range Discussion is below. Nothing definitive is showing up at this point for next weekend.

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
803 AM EST SUN FEB 14 2010

VALID 12Z THU FEB 18 2010 - 12Z SUN FEB 21 2010

MODEL DIFFERENCES INCREASE IN TIME THIS PERIOD AS THE WRN CONUS
RIDGE RETROGRADES ABOUT 10 DEGREES. A MEAN VORTEX LOCKS IN OVER
THE LOWER ST LAWRENCE RIVER VALLEY THIS PERIOD WITH A GRADUAL ERN
SHIFT TO EAST OF NOVA SCOTIA UNDER STRONG MID LEVEL RIDGING AND
POSITIVE HT ANOMALIES OVER LOWER DAVIS STRAIT WITH THE NEG AO/NAO
PATTERN. A STRONG ARCTIC VORTEX DROPS SWD TO NEAR 70N 100W. THIS
FEATURES ARE AGREED UPON.

WESTWARD AS THE MEAN RIDGE AXIS RETROGRADES TO THE EPAC HTS BUILD
NWD ALONG THE B.C. COAST INTO THE YUKON AND ERN AK INTO A CLOSED
MID LEVEL HIGH WITH GFS AGAIN TODAY ALLOWING MORE UNDERCUTTING
FLOW. ECMWF AND ITS MEAN ALONG WITH THE UKMET DROP SWD MUCH MORE
ENERGY FROM ALBERTA FORMING A DEEPER TROF OVER AND TO THE LEE OF
THE ROCKIES SUPRESSING THE SRN STREAM FLOW LATE WEEK TO WEEKEND.
IN TIME..BY DAY 8 BOTH MODELS BUILD AN EPAC REX BLOCK BUT ECMWF
AND ITS ENS MEAN HAVE A MUCH DEEPER MID NATION TROF CONTINING TO
SUPRESS THE SRN STREAM FLOW WITH GFS AND ITS MEAN LESS AMPLIFIED
AND HAVING A STRONGER SRN STREAM. TELECONNECTIONS BASED ON THE ERN
NOAM POSITIVE HT ANOMALY NEAR DAVIS STRAIT INDICATE SOME MDT EPAC
RIDGING AND A TROF OVER ERN CONUS. TELECONNECTING ON THE WRN
ANOMALY ALONG THE SRN AK COAST YIELDS A TROF FROM THE HUDSON BAY
REGION TO SOUTHWEST CONUS. THESE DUAL VERY STRONG POSITIVE
ANOMALIES WOULD YIELD A HYBRID OF THE TELECONNECTIONS THIS PERIOD
CLOSER TO THE ECMWF ENS MEAN. WHILE THE GFS FORECAST OF THE PNA
PATTERN IS NEAR NEUTRAL WITH A CONTINUATION OF THE VERY STRONGLY
NEGATIVE AO/NAO BELIEVE THE LONGER TERM GFS IN ERROR AND THE
STRONGER PNA TYPE PATTERN SUGGESTED BY THE ECMWF AND ITS ENS MEAN
OF A MORE AMPLIFIED SOLUTION OF A CENTRAL TO ERN CONUS TROF WILL
PREVAIL. D+8 ANALOGS THAT BEST FIT A STRONG NEG AO/NAO AND WARM
ENSO YEARS CONT TO BE FEB 1978 AND 1958.

HPC PRELIM PROGS START WITH A NEARLY EVEN BLEND OF THE ECMWF AND
ITS ENS MEANS FOR DAYS 3-5 WED/THU INCREASING TO A DOMINENT ECMWF
ENS MEAN DAYS 6 AND 7 SAT/SUN.

BREEZY WITH CONTINUED COLD ADVECTION FLOW OVER ERN CONUS WED TO
FRI. HIGH PRESSURE DROPPING SWD OVER THE ROCKIES WILL PROVIDE SOME
LT UPSLOPE SNOWS THRU THE NRN AND CENTRAL ROCKIES REGION MID TO
LATE WEEK. ECMWF AND ITS MEAN PREFERENCE OF A MORE AMPLIFIED TROF
SWINGING THRU THE SRN AND CENTRAL PLAINS LATE WEEK INDICATE A
POTENTIAL HVY SNOW THREAT FOR THE CENTRAL PLAINS FROM CO TO KS AND
MO FRI AND SAT.
ROSENSTEIN

[TatamyPA]

12z GFS finally shows an event for next weekend - albeit a weak one.

[LongIslandCoastalWx]

TatamyPA, on Feb 14 2010, 11:27 AM, said:

12z GFS finally shows an event for next weekend - albeit a weak one.

Looks something like this.

[LongIslandCoastalWx]

Thoughts from Seve D

Another major storm is possible towards the end of next weekend as an area of low pressure moves out of the Gulf of Mexico. This low has the potential to produce a significant snowfall sometime between late Sunday night through Tuesday.

[LongIslandCoastalWx]

12Z GGEM (Only out to 144 hours, but the model forms low pressure in the GOM)

[LongIslandCoastalWx]

12Z ECMWF (I think this our storm)

[forte408]

18z GFS has a monster, but slows it until the end of that week now.

[LongIslandCoastalWx]

forte408, on Feb 14 2010, 05:38 PM, said:

18z GFS has a monster, but slows it until the end of that week now.

I saw that. I'll have to see if it continues trending that way, and if it does, I'll change the dates. For now, I'll keep the dates the same.

[WrathOfPaulII]

how will our not-so-impressive monday night storm impact the potential for this one? would we want to sacrifice monday nights storm in order to get a bigger one at the end of the week? I remember someone saying that it would be more energy for the 2nd storm to tap into...