Potential Winter Storm March 6-7

[MJO812]

JMA

 

[Dsnowx53]

If we had a situation where the Euro was a hit and the GFS was a miss, but then the next GFS made changes like this, I would be quite enthused. But considering it's the Euro, this is not enough of a jump to get me excited.

I'm not giving up yet, but this run just doesn't do enough for me considering it's the Euro at 60-72 hours.

More often that not I would say essentially that it was game over given that Euro run at this range. But the dramatic changes aloft on the Euro, and the GFS and SREF showing us what just a slight shift can do, leaves me mildly interested.

Right, I feel the exact same way. Mildly interested describes it well.

Compare 84 on 00z with 96 on 12z at 500mb on WSI. Not amazing changes, but certainly noticeable ones. There was certainly more room for a phase with that shortwave that drops in from the northwest, and the heights tried to bend back a bit. Too bad these changes are at day 3 instead of day 5.

[JSantanaNYC]

Cant believe the euro didnt changed after the significant changes at 48hrs

[Weathergun]

The Euro has a some of our weaker threats, too far south of late. Since there is overall trend for some more northern steam interaction, I would think this will probably at least creep further north with time. We are also getting in the range where GFS typically does better. I think its best to go between the GFS and ECMWF, from here on out few runs. Unless there is some major change.

[earthlight]

Right, I feel the exact same way. Mildly interested describes it well.

Compare 84 on 00z with 96 on 12z at 500mb on WSI. Not amazing changes, but certainly noticeable ones. There was certainly more room for a phase with that shortwave that drops in from the northwest, and the heights tried to bend back a bit. Too bad these changes are at day 3 instead of day 5.

 

There were some fairly significant changes as early as 36-48 hours too. That's the main reason for my continued intrigue.

[Dsnowx53]

Right, I feel the exact same way. Mildly interested describes it well.

Compare 84 on 00z with 96 on 12z at 500mb on WSI. Not amazing changes, but certainly noticeable ones. There was certainly more room for a phase with that shortwave that drops in from the northwest, and the heights tried to bend back a bit. Too bad these changes are at day 3 instead of day 5.

There were some fairly significant changes as early as 36-48 hours too. That's the main reason for my continued intrigue.

Indeed. One subtle thing I noticed was that the ULL itself that the retrograding shortwave detached itself was further south, and much better defined/compact, yet not more suppressive... kinda like the GFS in that regard. This leads me to believe that there is more cyclonic flow in that area that would lead the shortwave to be forced westward.

It's just that the shortwave itself was not nearly as potent as it was on the GFS.

[kingwill42]

Will be interesting what Tomorrow mornings GFS shows(if it stands Firm or Caves to Euro) Also curious to see tomorrow afternoons Euro if GFS holds Firm.

[Clinch Leatherwood]

There were some fairly significant changes as early as 36-48 hours too. That's the main reason for my continued intrigue.

All year long including the blizzard the Euro has been a southwest/slow outlier with upper lows. With our first blizzard it insisted for 3-4 runs the low would stall se of ack only to finally cave to the more ne models. Wsi still has last nights 0z up, look at the steady move Ene of the ULL as it exits the Carolina's. every 12 hours the new run is faster. Really all that separates a more significant hit on this run of the euro is a 100 or so miles on the ULL ( roughly speaking) to get it further NE before the energy digs down from the lakes. Based on a winter in which the euro almost always was among the last models to come north on the cape scrapers, the blizzard and the follow on 4" which it was too supressed on at 6 hours lead time.... I will hedge my bets that we see a faster ULL ejection.

The gfs was way overdone in the scrapers. But it did correctly signal the threat and I think this is no different. NYC, Long Island and at least south coastal New England will be impacted I think. It's late, just trying to relate what I've seen this year.

[earthlight]

All year long including the blizzard the Euro has been a southwest/slow outlier with upper lows. With our first blizzard it insisted for 3-4 runs the low would stall se of ack only to finally cave to the more ne models. Wsi still has last nights 0z up, look at the steady move Ene of the ULL as it exits the Carolina's. every 12 hours the new run is faster. Really all that separates a more significant hit on this run of the euro is a 100 or so miles on the ULL ( roughly speaking) to get it further NE before the energy digs down from the lakes. Based on a winter in which the euro almost always was among the last models to come north on the cape scrapers, the blizzard and the follow on 4" which it was too supressed on at 6 hours lead time.... I will hedge my bets that we see a faster ULL ejection.

The gfs was way overdone in the scrapers. But it did correctly signal the threat and I think this is no different. NYC, Long Island and at least south coastal New England will be impacted I think. It's late, just trying to relate what I've seen this year.

It's just so difficult to weight the NCEP guidance into a forecast at this range given the track record, especially when it comes to the precipitation shields northward extent and ticking surface lows in too close to the coast. But you are correct in the fact that the Euro has tapped out several times this year with a slightly too far south solution.

The SREF from 21z are still very amped up, but after thinking about it for a few minutes I wouldn't take them into much consideration. Not only are they at the tail end of their useful range, but the amplified members are all ARW and half of NMM nest...which have a tremendous bias of being not only too amplified, but far too wet as well. Some of them are producing 3" QPF bombs over NYC. If you take them out of the mean plumes, the expected QPF drops drastically.

That leaves us essentially with the GFS and Euro (forgetting the GGEM which has been disappointingly inconsistent since it's uber upgrade). The GFS handling of the ULL over the NW Atlantic is extremely intriguing and I think the Euro definitely took some steps that way. We've also seen the GFS trend farther southeast with that northern stream vort over the Lakes for 4 runs in a row.

I think in the end this ends up somewhere in between, leaning towards the Euro...like the most of them. Buf this specific situation definitely holds promise for a big jump in either direction..specifically a big jump from a Euro solution to a GFS type solution..with some very minor tweaks aloft.

[WE GOT HIM]

It's just so difficult to weight the NCEP guidance into a forecast at this range given the track record, especially when it comes to the precipitation shields northward extent and ticking surface lows in too close to the coast. But you are correct in the fact that the Euro has tapped out several times this year with a slightly too far south solution.

The SREF from 21z are still very amped up, but after thinking about it for a few minutes I wouldn't take them into much consideration. Not only are they at the tail end of their useful range, but the amplified members are all ARW and half of NMM nest...which have a tremendous bias of being not only too amplified, but far too wet as well. Some of them are producing 3" QPF bombs over NYC. If you take them out of the mean plumes, the expected QPF drops drastically.

That leaves us essentially with the GFS and Euro (forgetting the GGEM which has been disappointingly inconsistent since it's uber upgrade). The GFS handling of the ULL over the NW Atlantic is extremely intriguing and I think the Euro definitely took some steps that way. We've also seen the GFS trend farther southeast with that northern stream vort over the Lakes for 4 runs in a row.

I think in the end this ends up somewhere in between, leaning towards the Euro...like the most of them. Buf this specific situation definitely holds promise for a big jump in either direction..specifically a big jump from a Euro solution to a GFS type solution..with some very minor tweaks aloft.

Great Points as always

[Dsnowx53]

I'm getting exhausted, but I just wanted to say that John and Rollo make good points in their posts.

The ARW members of the SREFS were the ones that gave us blizzards during the February 16 "event".

[Weathergun]

The models are often too far south with ULLs. In fact, the Euro ensembles have been almost always been further north with the ULL than the OP Euro.

 

 

[CooL]

New srefs are still wet, 0.75"+ for most of us

[earthlight]

New 03z SREFs are in..and they are still very amped up. For the little that its worth.

[CooL]

At hr 240 on the euro the storm is still just a few hundred miles SE of nova scotia lol

[CooL]

Not bad

 

[WE GOT HIM]

Nam relatively similar through 36. The block looks to be slightly more north.

[CooL]

Pretty big changes on the NAM thru 42 hrs. Northern stream from the ULL def more involved.

[chademer07]

Using Raleighs maps you can definitely see a big difference at hour 42. This should almost be a lock to come north, just not sure how much.

Pretty big changes on the NAM thru 42 hrs. Northern stream from the ULL def more involved.

[chademer07]

It seems almost every model suite has weakened the block to our north for the last 2 days as well, I would expect that trend to continue.

[WE GOT HIM]

Looking good at 45. This run will deff be north.

[CooL]

Light-Mod precip up to the city at hr 69

 

good trends this run

[WE GOT HIM]

Light-Mod precip up to the city at hr 69

 

good trends this run

Yea, Sooo Close this run but a very good trend. Took a big step toward the GFS.

- Also colder.

[wolfie09]

mount holly

 

 

 

THE MDLS REMAIN IN VERY GOOD AGREEMENT OVERALL. THE 04/00Z GFS ISA BIT FASTER, AS IS USUALLY THE CASE WITH PRECIP ONSET, EVENTHOUGH THE ECMWF HAS BECOME A BIT FASTER THIS CYCLE. THE 04/00ZGFS IS ALSO THE FURTHEST N OF THE MDL CONSENSUS. NEVERTHELESS,DESPITE THE MORE NWD POSN OF THE GFS, THE OVERALL FCST RATIONALEHAS NOT CHANGED. SENSIBLE WX-WISE THE GREATEST IMPACTS WILL BEOVER SRN AREAS WITH LESS AS ONE GOES N. IF THE ECMWF AND SOME OFTHE MORE SRN SOLNS ARE CORRECT, THERE MAY BE MINIMAL IMPACTS OVERNRN AREAS. IF THE GFS IS CORRECT THERE WOULD BE SOME WX OVER NRNPORTIONS OF THE REGION.AFTER THE LOW REACHES THE SERN VA CST THE MDLS GENLY MOVE IT OUTTO SEA. THE GFS BRINGS IT EWD OR NEWD, WHILE THE ECMWF HAS ITMOVING ALMOST SEWD THEN EWD AND THE CMC ALMOST EWD. THIS PATH ANDSPEED WILL ALSO PLAY A ROLE IN THE IMPACTS OVER OUR REGION AND HOWLONG THEY LAST.AGAIN, FOR MOST AREAS, THIS WILL BE A RAIN OR MOSTLY RAIN EVENT.DEPENDING ON THE TIMING, PRECIP WILL BEGIN OVER SRN AREAS LATE TUEAFTN OR TUE EVE AS RAIN. DURG TUE NIGHT THERE COULD BE SOME WINTRYPRECIP OVER THE NRN AREAS, IF THE PRECIP MAKES IT THAT FAR N,WITH RAIN EVERYWHERE ELSE. SNOW COULD MIX IN OVER WRN SECTIONS BY DAYBREAK.DURG WED, EXPECT ALL RAIN, SOME OF WHICH COULD BE HEAVY FORVIRTUALLY ALL AREAS, EXCEPT FOR THE EXTREME N. THEN, BY WED NIGHT,PRECIP WILL BEGIN TO MIX BACK WITH SNOW FROM THE N AND W, ANDDEPENDING ON HOW THINGS PLAY OUT AND HOW FAST THE LOW IS MOVG,THERE COULD BE SOME LIGHT ACCUMS BY THU MRNG.OVERALL QPF AMTS ARE GENLY OVER AN INCH ACRS THE EXTREME S, AROUND0.50 INCHES CNTRL AND A SHARP CUT OFF TO THE N. IF THE MORE SLYSOLN PANS OUT, THE EXTREME NRN AREAS COULD ONLY BE LOOKING AT AFEW HUNDREDTHS TO A TENTH OF QPF.WIND WILL BE ANOTHER CONCERN, WITH WIND PICKING UP DURG THE DAY ONWED AND CONTINUING INTO THU BEFORE DECREASING ON FRI. WINDS COULDGUST AS HIGH AS 30 TO 35 MPH WITH EVEN 40 TO 45 MPH CLOSER TO THECOAST.AS WE HAVE BEEN DOING FOR SEVERAL DAYS NOW, DUE TO THE CLOUDY SKYAND ABUNDANT PRECIP, WE ARE UNDERCUTTING MOS TEMPS BOTH WED AND THU.FINALLY, DEPENDING ON WHICH MDL YOU WANT TO BELIEVE, THE LOW WILLBE EXITING STAGE RIGHT DURG THU AFTN OR EVE AS HIGH PRESSUREBUILDS DOWN FROM CANADA. THE PGRAD BETWEEN THESE TWO SYSTEMS WILLKEEP A GUSTY NW WIND FOR AWHILE, BUT CONDS SHUD IMPROVE. THEN, THUNIGHT, FRI, AND SAT LOOK DRY AND PLEASANT WITH THE HIGH IN CONTROLAND TEMPS NR OR SLIGHTLY ABV NRML.

 

 

http://forecast.weather.gov/product.php?site=NWS&issuedby=PHI&product=AFD&format=CI&version=1&glossary=1&highlight=on

 

 

 

Upton

 

 

THE MAIN FOCUS OF THE LONG TERM IS THE POTENTIAL IMPACTS FROM ACOASTAL LOW WED-THU WHICH WILL BE FORMING AS A STRONG UPPER LEVELLOW MOVES SOUTHEAST INTO THE TENNESSEE VALLEY. MODELS REMAINCONSISTENT WITH THIS LOW DEVELOPING...HOWEVER MODELS ARE NOT INAGREEMENT WITH RESPECT TO HOW FAR NORTH THE LOW WILL TRACK.DEPENDING ON HOW FAR NORTH THE LOW TRACKS...WILL EVENTUALLYDETERMINE HOW MUCH AND WHAT KIND OF PRECIPITATION THE CWA WILL SEE.

THE 04/00Z GFS CAME IN MUCH WETTER THAN ITS PREVIOUS RUNS...HOWEVERTHE 04/00Z ECMWF...WHICH HAS BEEN THE MORE CONSISTENT MODELLATELY...KEEPS THE MOST IF NOT ALL OF THE PRECIPITATION SOUTH OF THEREGION. THEREFORE...HAVE NOT MADE TOO MANY CHANGES TO THE PREVIOUSFORECAST. WONT GO ANY HIGHER THAN CHANCE POPS AT THIS POINT.WITH RESPECT TO QPF...WONT MAKE MUCH CHANGE TO WHAT IS ALREADYFORECAST WITH AMOUNTS ON THE LIGHT SIDE AND GENERALLY UNDER 0.3INCH. WITH PTYPE...MAINLY SNOW INITIALLY EVERYWHERE LATE TUESDAYNIGHT/EARLY WEDNESDAY MORNING...THEN CHANGING TO RAIN ALMOSTEVERYWHERE DURING THE DAY WEDNESDAY. THE PRECIPITATION THEN CHANGESBACK TO SNOW WEDNESDAY NIGHT AND THURSDAY BEFORE COMING TO AN END.COLDER SOLUTION WAS PREFERRED TO ACCOUNT FOR DYNAMIC COOLING FROMDEEPENING OF LOW WHEN THE SURFACE WINDS TURN MORE NORTHERLY.

 

 

http://forecast.weather.gov/product.php?site=NWS&issuedby=OKX&product=AFD&format=CI&version=1&glossary=1&highlight=off

[WE GOT HIM]

6z GFS is just slightly south of 0z but has much heaver precip just off LI.

[WeatherX]

6z GFS pretty much dead on the 0z run through 81 hours, does look slightly colder at the surface though.....988mb at 39N/69W

[WintersGrasp]

GFS is probably 6"+ for NE NJ up through NE. Bit further south but similar results

[WE GOT HIM]

GEFS agrees with op maybe a hair wetter. Looks like 1.25" is in southern Queens.

[MJO812]

Nice is a nice look on the 6z GEFS

[Rtd208]

According to the New England thread the Euro ensembles shifted a little bit south, also a couple of the mets seem to think the GFS will eventually cave to the other "south" models.