Friday February 8th Storm Potential

[Weathergun]

It's going to be tough to kill the primary since we are in a northern stream dominant pattern. We had a version of this last

February when the northern stream was too strong pushing the southern stream development further east.

 

500mb-20120211-12z.gif

 

The GFS has the northern stream keeping the low and mid-levels warm and kicking out the southern stream. We are almost certain not to see a west-based -NAO. So our best hope is either for higher heights over the Rockies/Central Plains or a stronger southern stream, to cause the northern stream to dig more. The 0z ECMWF has both happening. Which is why is much closer to phasing for our area.

[Weathergun]

It's going to be tough to kill the primary since we are in a northern stream dominant pattern. We had a version of this last

February when the northern stream was too strong pushing the southern stream development further east.

 

500mb-20120211-12z.gif

 

The GFS has northern stream keeping the low and mid-levels warm and kicking out the southern stream. We are almost certain not to see a west-based -NAO. So our best hope is either for higher heights over the Rockies/Central Plains or a stronger southern stream, to cause the northern stream to dig more. The 0z ECMWF has both happening more. Which is why is much closer to phasing for our area.

[jm1220]

The GFS has the northern stream keeping the low and mid-levels warm and kicking out the southern stream. We are almost certain not to see a west-based -NAO. So our best hope is either for higher heights over the Rockies/Central Plains or a stronger southern stream, to cause the northern stream to dig more. The 0z ECMWF has both happening. Which is why is much closer to phasing for our area.

Even on the Euro, the ridge axis is over the eastern Plains, which is well east of where you would want it for a big storm here. There's also a big bowling ball low on its heels pushing that east. There's a semblance of a 50-50 low, but north of where we want it. The flow still looks too progressive to show any real confidence of a hit here. The primary low is also quite evident here. It COULD happen for us if the streams phase in the right spot and the systems are powerful enough to temporarily slow down the flow, but it's highly unlikely. I would urge caution at jumping on any big storm solution.

[MJO812]

SREF is also more amped up on the 9z run. It's way out there though.

 

http://mag.ncep.noaa.gov/Image.php?model=sref&area=namer&param=mslp&cycle=09ℑ=sref%2F09%2Fsref_namer_087_mslp.gif

[Zir0b]

SREF is also more amped up on the 9z run. It's way out there though.

 

http://mag.ncep.noaa.gov/Image.php?model=sref&area=namer&param=mslp&cycle=09ℑ=sref%2F09%2Fsref_namer_087_mslp.gif

look at the individuals. Not a single solution would be even close to snow for this area

[ace0927]

I just don't see how this is a nyc snowstorm without a west based nao block in place, there's not even a good pna right now. New England is a different story...

not to cause a raucous, but you realize that there have been plenty of snow storms without a west based -nao, right? Jan 21 1978, Jan 1987, Feb 2003, March 1993 January 2005...im NOT saying this will play out the same (all of those had other things working for them that this storm wont/doesnt have)  but that isnt 100% necessary...in this setup it might be, however.

[FPizz]

The SREF's have pretty much been wrong just hours before precip gets here all season.  87 hours out is even more of a joke. 

[ace0927]

Euro has not had a good track record this year when it's on its own. Unless the 12z suite makes a big step toward the 0z Euro's solution, I'd expect it to back down from its outlier solution. 

 

i think most models went towards the Euro. GGEM/GFS/UKMET....

[BxEngine]

not to cause a raucous, but you realize that there have been plenty of snow storms without a west based -nao, right? Jan 21 1978, Jan 1987, Feb 2003, March 1993 January 2005...im NOT saying this will play out the same (all of those had other things working for them that this storm wont/doesnt have) but that isnt 100% necessary...in this setup it might be, however.

Who hacked ace's account? Lol

[mikemurph44]

not to cause a raucous, but you realize that there have been plenty of snow storms without a west based -nao, right? Jan 21 1978, Jan 1987, Feb 2003, March 1993 January 2005...im NOT saying this will play out the same (all of those had other things working for them that this storm wont/doesnt have) but that isnt 100% necessary...in this setup it might be, however.

. Yes I know you can get a major snowstorm without a -nao in nyc, but when you add in the lack of a +pna as well...lets just say I would not bet my weeks salary on it

[IsentropicLift]

The 00z NOAGPS take the primary as a 1008 mb low just east of ACY

 

[NaoPos]

if you want, check out the philly sub forum medium range thread. HM adding some insight to this possible event.

[earthlight]

not to cause a raucous, but you realize that there have been plenty of snow storms without a west based -nao, right? Jan 21 1978, Jan 1987, Feb 2003, March 1993 January 2005...im NOT saying this will play out the same (all of those had other things working for them that this storm wont/doesnt have) but that isnt 100% necessary...in this setup it might be, however.

Yeah we've definitely seen our fair share of major events without a west based nao block. But this set up really needs it, I think.

[JERSEYSNOWROB]

Per HM in the Philly thread: I would say things are 65/35 that this is mostly a winter type of system and not rain.

[Edge Weather]

HM is all over this potential in the Philly forum, but here is just one of his many posts in the past hour or so:

 

 

Well I wouldn't call it a long shot though. The 6z GFS only warms the 850mb temps above 0C because the CCB fails to develop in time. But you have to admit that it has an impressive southern stream wave which it did NOT have up until last night. Actually, it trended on the 18z run but failed to have a northern s/w. I would say things are 65/35 that this is mostly a winter type of system and not rain.

 

My biggest worry is the compressing flow somehow prevents either s/w from interacting and we get the classic separation as tombo suggested.

[donsutherland1]

. Yes I know you can get a major snowstorm without a -nao in nyc, but when you add in the lack of a +pna as well...lets just say I would not bet my weeks salary on it

Current PNA value is +0.400. It should be neutral to weakly positive at the time the storm develops.

[NEG NAO]

UPTON

 

THERE ARE DIFFERENCES BETWEEN THE OPERATIONAL RUN OF THE 00Z/05

GFS AND THE 00Z/05 ECMWF...THE MOST NOTABLE OF WHICH IS THAT THE

GFS HAS A TRACK SOUTH OF THE 40/70 BENCHMARK AS OPPOSED TO THE

ECMWF...WHICH BRINGS THE LOW RIGHT OVER THE BENCHMARK. THE GFS IS

ABLE TO PUSH SOME WARMER AIR INTO THE REGION...WHICH WOULD RESULT

IN SNOW INITIALLY...THEN MIXING AND CHANGING TO RAIN. THE

ECMWF...ON THE OTHER HAND...HAS A DEEPER TROUGH ALONG THE EAST

COAST...WHICH BRINGS COLDER AIR INTO THE LOCAL AREA AND KEEPS THE

PRECIP AS SNOW. MOST OF THE GFS ENSEMBLE MEMBERS FOLLOW A TRACK

SIMILAR TO...AND JUST SOUTH OF...THE 00Z GFS. THE GFS ENSEMBLE

MEAN IS ALSO SIMILAR TO THE 00Z OPERATIONAL GFS. THE STORM

ASSOCIATED WITH THE ECMWF IS ALSO DEEPER AND PRODUCES MORE QPF

THAN THE GFS.

CANNOT RULE OUT THE ECMWF...AS THAT WOULD BRING WINTER STORM WARNING

 

THEY GO ON TO SAY THEY ARE SIDING WITH THE WARMER SOLUTION FOR NOW .

stay tuned

good idea to side with the solution which brings the minimal amount of snow - because this pattern does not support anything else - ie. NAO - near neutral - PNA near neutral and AO near neutral - all might be on one side of neutral slightly - difficult to determine - regardless does not support a big east coast storm

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index_ensm.shtml

[MJO812]

The PNA is slightly positive so that might help some amplification for the storm.

[NEG NAO]

Current PNA value is +0.400. It should be neutral to weakly positive at the time the storm develops.

Don - are there any big east coast storms or even moderate storms on record where all 3 indicies NAO PNA and AO where very close to neutral at the same time ?

[jm1220]

The PNA is slightly positive so that might help some amplification for the storm.

Look how far east the ridge axis is. That's a pretty big point of concern for me. I'd rather it be a few hundred miles or so west of there.

[MJO812]

Look how far east the ridge axis is. That's a pretty big point of concern for me. I'd rather it be a few hundred miles or so west of there.

 

The ridge axis is a concern. I think this storm will be a thread the needle event anyway for our area. The one thing that I am liking is the high pressure to the north. If that can come more south , there will be more colder air for our region.

[rossi]

Per HM in the Philly thread: I would say things are 65/35 that this is mostly a winter type of system and not rain.

 

Has anyone looked at DT's post about oz Euro.

 

His maps seem to indicate that we get mostly snow. Can some one look and let me know if you agree.?

 

 

Rossi

[NEG NAO]

The ridge axis is a concern. I think this storm will be a thread the needle event anyway for our area. The one thing that I am liking is the high pressure to the north. If that can come more south , there will be more colder air for our region.

what is going to even hold it in place ?

[NEG NAO]

Has anyone looked at DT's post about oz Euro.

His maps seem to indicate that we get mostly snow. Can some one look and let me know if you agree.?

Rossi

I agree we get mostly snow - BUT not enough precip because of the progressive flow and lack of indicie support - so we end up with the usual coating to an inch or 2 - except this time it does not come from a clipper

[rossi]

I agree we get mostly snow - BUT not enough precip because of the progressive flow and lack of indicie support - so we end up with the usual coating to an inch or 2 - except this time it does not come from a clipper

Huh - Not the case  with a coastal system.

 

Rossi

[MJO812]

I agree we get mostly snow - BUT not enough precip because of the progressive flow and lack of indicie support - so we end up with the usual coating to an inch or 2 - except this time it does not come from a clipper

 

Coating to an inch from a coastal storm? We still don't know yet if the Euro is right with the storm. I would like to see the GFS jump on board.

[NEG NAO]

Huh - Not the case with a coastal system.

Rossi

ok I will agree -IF someone can show me when is the last time we had a moderate or heavy snow event here from a coastal storm when the AO PNA and NAO are very close to neutral at the same time -

[mikemurph44]

Don - are there any big east coast storms or even moderate storms on record where all 3 indicies NAO PNA and AO where very close to neutral at the same time ?

. I would think it very rare with the exception of new england. I'm sure don can shed some light on it. I can get over the lack of a west based -nao and -ao, but with the lack of a solid +pna as well? I would not headge any bets on those odds

[wolfsheepsheadbay]

I agree we get mostly snow - BUT not enough precip because of the progressive flow and lack of indicie support - so we end up with the usual coating to an inch or 2 - except this time it does not come from a clipper

The 0z Euro is .60 QPF and mostly snow.

[CIK62]

The 0Z high-res EURO for NEUS shows (for NYC)  Rn.  @90hrs. ie. Fri.  AM, Hv.Rn. @96hrs., Mixed Lt. @102hrs.,  Lt.Sn. ending @108hrs., ie early Sat. AM.

32deg. line forced north before onset, then is able to come back at end.   

What is the thrill here?   32deg. line goes far north of us.   I would call 30 miles away a close call, but this is more than that at height of precip. here.