Late February/Early March Medium and Long Range Discussion Thread

[Dsnowx53]

Since this SW is still 1000 miles south of the Aleutians and 6 days out  , I will refrain from throwing the threat away,until theres at least 1 West coast sampling and we are inside 96 hours .Hard to expect a goldilocks scenario 150  plus hours out .

 

Maybe it is an Atlanta to Roanoke special , but do you really wana go all in on that this far out  ?  I said 2 days ago I thought a  3 to 4 SD below normal in the NAO may not be to our benefit , but will wait until Monday to see if anything in the modeling takes on a different look .

 

Remember at 6 days out , if theres  the smallest  variable missed in any of the models initialization , it gets magnified downstream .

The GFS may be right in the end  but at 150 - 170 hrs away it really is outside its effective range , so I just cant look at it until we are inside 96 hours .

The Euro has really backed off , as has its control and the overnite ensembles .

It`s an uglier solution and that I will not deny .I will wait a few days until its on the grid to close the window  otherwise , at 150 hrs the spray stil gives you a shot .

 

 

Yeah, the block may be too strong and poorly oriented this time around. Change the orientation of the block, though, and the odds of a major snowstorm go up. 

 

As far as the models go, the GFS is initially similar to other guidance, but after 96 hours, becomes very different, as almost all other guidance breaks off a vort from the northern stream, whereas the GFS does not. 

The problem though is that even with the phase, the storm might not be able to climb up the coast because there is lots of confluence in the Atlantic, since the block is too far west based. Last night's Euro run phased very early, but it didn't climb up the coast. It's not just about the timing of the phase...it's about the orientation and strength of the block as well, which is what's concerning. I do favor some sort of phase at this time, fwiw.

[Dsnowx53]

The NAVGEM is closer to the Euro than the GFS through 120.

 

nvg10.500.120.namer.gif

 

 

It's much more meridional out west than the other guidance. Plus, its confluence is not as overwhelming, so we actually see a semblance of SE ridging trying to connect to the block, as opposed to Midwest ridging. The height rises ahead of the storm are much more impressive on the NAVGEM than other guidance. 

[Dsnowx53]

we should probably ignore the fact that there isnt any real cold air around (for like the 10th time this winter season) also...

 

and for the 17th time this winter season the big -NAO advertised by the Euro in the 7-10 day frame won't and hasn't materialized...

 

 

The air mass is fine. In this pattern, if we get a strong storm system taking a favorable track, the cold air will be there, period. 

 

That being said, although you're wrong about the NAO block not materializing...since clearly there is a strong NAO in place before the storm, you do have a point about the orientation. Its orientation has not trended favorably on the latest set of guidance; I would rather see it where it was initially forecast, as you stated. Since it is so strong and oriented to the west on most guidance, the downstream confluence and troughing is stronger and right near our coastline; making height rises ahead of our storm minimal. However, the orientation of the block can certainly change with time. A more eastward oriented block will force the confluence to move further east, increasing the height rises out ahead of our storm. 

 

That being said, I really do not think we can get a good snowstorm unless those changes occur. 

[jm1220]

Since this SW is still 1000 miles south of the Aleutians and 6 days out  , I will refrain from throwing the threat away,until theres at least 1 West coast sampling and we are inside 96 hours .Hard to expect a goldilocks scenario 150  plus hours out .

 

Maybe it is an Atlanta to Roanoke special , but do you really wana go all in on that this far out  ?  I said 2 days ago I thought a  3 to 4 SD below normal in the NAO may not be to our benefit , but will wait until Monday to see if anything in the modeling takes on a different look .

 

Remember at 6 days out , if theres  the smallest  variable missed in any of the models initialization , it gets magnified downstream .

The GFS may be right in the end  but at 150 - 170 hrs away it really is outside its effective range , so I just cant look at it until we are inside 96 hours .

The Euro has really backed off , as has its control and the overnite ensembles .

It`s an uglier solution and that I will not deny .I will wait a few days until its on the grid to close the window  otherwise , at 150 hrs the spray stil gives you a shot .

I would wait a few days and hold back before declaring this dead or a real threat. Much can and will change.

[PB GFI]

Yeah, the block may be too strong and poorly oriented this time around. Change the orientation of the block, though, and the odds of a major snowstorm go up. 

 

As far as the models go, the GFS is initially similar to other guidance, but after 96 hours, becomes very different, as almost all other guidance breaks off a vort from the northern stream, whereas the GFS does not. 

The problem though is that even with the phase, the storm might not be able to climb up the coast because there is lots of confluence in the Atlantic, since the block is too far west based. Last night's Euro run phased very early, but it didn't climb up the coast. It's not just about the timing of the phase...it's about the orientation and strength of the block as well, which is what's concerning. I do favor some sort of phase at this time, fwiw.

 

Agree , and if you look at the Euro ensembles , thats only about 150 miles away from firming up .

With a week to go , we aren`t 1000 miles off  .I wouldnt be shocked if the modeling was able to displace the block 100 or so miles over a  6 day period . That why I am thinking let this get sampled , lets be inside 96 hours then we can

really see if this is closer to a favorable solution .

 

I cant hang on an operational run at 150 hrs out , Im uncomfortable picking apart the atmosphere as it is a week out .

[Dsnowx53]

The Euro ensembles are further north with the low this run than the OP.

 

MSLP_North32America_168.gif

 

Geopotential32at32500hPa_North32America_168.gif

 

 

Certainly good news. A few members probably bring us snow, based on that look. 

[Dsnowx53]

Agree , and if you look at the Euro ensembles , thats only about 150 miles away from firming up .

With a week to go , we aren`t 1000 miles off  .I wouldnt be shocked if the modeling was able to displace the block 100 or so miles over a  6 day period . That why I am thinking let this get sampled , lets be inside 96 hours then we can

really see if this is closer to a favorable solution .

 

I cant hang on an operational run at 150 hrs out , Im uncomfortable picking apart the atmosphere as it is a week out .

 

 

Definitely agree with you here. 

[MJO812]

GGEM ensemble mean

 

http://raleighwx.americanwx.com/models/cmcensemble/12zggemensemblep12168.gif

[bmc10]

"I had a dream"....

 

This is not a block, If you think this is a snow storm h5 map you dont pay attention:

now here is the euro from 3.5 days ago...this is what I was talking about: This WILL NOT come too fruition: notice the real dual blocking justs south of Greenland and just north of alaska.

 

Just because you don't favor the look at h5 or don't like the orientation of the block, does not mean that one does not exist. There is clearly a block, maybe not where or how we would ideally like it. I also wasn't saying this setup will produce, my point was that it could snow if everything came together. Just like it did for Feb 8th, even with a marginal air mass.  

[RU848789]

those who bet the under on March snowfall in the NYC area are looking real solid right about now.

Considering the poor accuracy of deterministic models more than about 5-6 days out, that's kind of a silly statement, since nobody really knows what the rest of March will bring. 

[ace0927]

Considering the poor accuracy of deterministic models more than about 5-6 days out, that's kind of a silly statement, since nobody really knows what the rest of March will bring. 

 

 

Considering the poor accuracy of deterministic models more than about 5-6 days out, that's kind of a silly statement, since nobody really knows what the rest of March will bring. 

if its anything like the past 15 or so March's (sans one here and there), it wont bring much. For all intense and purposes March is no longer a winter month around these parts

[JSantanaNYC]

if its anything like the past 15 or so March's (sans one here and there), it wont bring much. For all intense and purposes March is no longer a winter month around these parts

October is not a Winter month.. neither is November. and we had snow the past two years during those months. 

[nzucker]

if its anything like the past 15 or so March's (sans one here and there), it wont bring much. For all intense and purposes March is no longer a winter month around these parts

December has been snowier than normal recently; March has been less snowy than usual. Both months are similar in temperature profile historically. Climo will even things out eventually...we'll have a string of snowy Marches and poor Decembers.

I hope we finally get a snowy March this year...we're really overdue. Models have backed off a little but the pattern seems favorable overall. We could see another favorable period from March 15-20 with the PNA and EPO bringing fresh cold after the major threat on 3/4.

[96blizz]

We all know it can snow, and snow hard, in March around here --- at least if you're old enough to remember March of 1993 --- and it's false logic to say the last 15 or so March's have proven this.  There are some pretty strong pieces of that type of puzzle possible here that could be in play and we'll have to watch this all unfold and enjoy!

[Edge Weather]

Some food for thought.... with the previous blizzard the Euro had indicated a possible storm for our area, albeit quite weak, in the long distance, out past 192 hrs, then dropped it completely until it re-appeared at 138 hrs, then the Euro never lost it.  We have many times seen the models show a storm in the longer ranger, out at 10 days through 7 days, only to have them then disappear, or not affect our area, only to reappear when the data gets sampled as the energy re-appears over North America around 4-5 days out.  I am not saying this will happen this time at all, but it would not surprise me in the least if it did. 

[CooL]

GFS has an unfavorable setup with the ULL over the northeast and no energy over the lakes to phase with..That has ots written all over

[NEG NAO]

new thread for the march 6th - 7th storm as the Euro ensembles are now closer to the coast

 

http://www.americanwx.com/bb/index.php/topic/39541-march-6-7-potential-winter-storm/

[ace0927]

December has been snowier than normal recently; March has been less snowy than usual. Both months are similar in temperature profile historically. Climo will even things out eventually...we'll have a string of snowy Marches and poor Decembers.

I hope we finally get a snowy March this year...we're really overdue. Models have backed off a little but the pattern seems favorable overall. We could see another favorable period from March 15-20 with the PNA and EPO bringing fresh cold after the major threat on 3/4.

Thanks for the input...and im sure you are right about the even-ing out of Dec and March...

 

March 15-20 is awfully late....at that point id rather just have 62 and sunny so I can hit the links...

[uncle W]

March and early April can have days in the 80's or 90's and snow just before or after it happens...

March 1990...snow and cold around the 7th...85 degrees mid month...1" of snow April 7th...

March 1998...snow on the 22nd...80 degrees or higher the last five days of the month...

April 2000...upper 70's one day and 2" of snow the next morning...the Spring of 1964 had its ups and downs...snow on the 22nd...75 degrees a few days later...22 degrees on the 31st...Coldest for the month...Early April it gets into the 70's again but the next morning was below freezing...

April 1976 and 2002 had cold spells the beginning of April and heat waves around the 18th...These extremes make Spring interesting...

 

 

 

[Blizzardo]

I remember a storm in march.. Bloomfield had rain. My buddy and I drove out rt.80 and when we hit denville. We watched as we drove.. the snow get deeper and deeper.. got off on rt. 15 with 2-3 feet of snow. Each made 600 for the day plowing driveways and getting people unstuck. Drove back to Bloomfield and started spring clean ups the next day...I'll never forget it but don't remember the date. I'm going to say around 94' ??

[Guest Pamela]

I remember a storm in march.. Bloomfield had rain. My buddy and I drove out rt.80 and when we hit denville. We watched as we drove.. the snow get deeper and deeper.. got off on rt. 15 with 2-3 feet of snow. Each made 600 for the day plowing driveways and getting people unstuck. Drove back to Bloomfield and started spring clean ups the next day...I'll never forget it but don't remember the date. I'm going to say around 94' ??

 

Probably March 31 1997. 

[bluewave]

The MJO staling out in 7 would mean a milder pattern for the second week of March.

 

 

 

 

 

 

 

 

 

 

 

[uncle W]

The MJO staling out in 7 would mean a milder pattern for the second week of March.

 

ECMF_phase_MANOM_51m_full.gif

 

MarchPhase7500mb.gif

 

00zECMWFENS500mbHeightAnomalyNH216.gif

I believe 1997 had a little snow before this and 1984 had a good size snowstorm...