Winter Storm Threat *Technical* Discussion. No Op Run PBP or Snow maps

[WEATHER53]

This concept is solid but lack of participation exemplifies the model hugging and loving 

[CAPE]

48 minutes ago, WEATHER53 said:

This concept is solid but lack of participation exemplifies the model hugging and loving 

We still rely on model guidance itt, but no snow map hugging, and no bitching and complaining after every 'bad' op run.

[CAPE]

Not enthused about this storm potential overall, but given the 6z run and that 12z was close- it just missed a phase(occurs too late offshore) and so off the coast the primary shortwave goes without gaining enough latitude. Main takeaway even with a miss at 12z, the best physics based model we have access to thinks its cold enough to snow in much of the region given a strong LP and track to our south, at least for now.

 

[Ji]

I didnt love the long range EPS--seemed a bit warmer. Trough was deeper on west coast. Not a shutout pattern but this would favor 40N more i think

[Ji]

2 minutes ago, Ji said:

I didnt love the long range EPS--seemed a bit warmer. Trough was deeper on west coast. Not a shutout pattern but this would favor 40N more i think

maybe its a delay but not denied but we cant really afford a delay lol

[CAPE]

5 minutes ago, Ji said:

maybe its a delay but not denied but we cant really afford a delay lol

Yeah its actually 'caving" a bit to the GEFS, which hasn't been as enthusiastic about the favorable look in the NA or the western trough weakening/progressing eastward after the 20th. We shall see.

[Ji]

DT is ending winter based on the GFS MJO that takes it strongly into 4,5,6

meanwhile Euro loves the non impact neutral circle

[CAPE]

25 minutes ago, Ji said:

DT is ending winter based on the GFS MJO that takes it strongly into 4,5,6

meanwhile Euro loves the non impact neutral circle

lol DT. He is still relevant?

[Ji]

1 minute ago, CAPE said:

lol DT. He is still relevant?

He still has a huge following so yes!

[NorthArlington101]

3 minutes ago, CAPE said:

lol DT. He is still relevant?

I work with a lot of Richmond folks and whenever they know I like snow or weather they ask about DT.

[Scarlet Pimpernel]

I haven't really paid much attention to the somewhat longer range in awhile.  But is the previously thought more favorable NA later this month and early March now looking less likely?  I recall there was some discussion awhile back about a PV split, and being on our side of the hemisphere, with a good shot at a return to more blocking around that time period.  Not sure of the details though.  It doesn't seem like the Pac side is going to do much to become better.

[Ji]

3 minutes ago, Scarlet Pimpernel said:

I haven't really paid much attention to the somewhat longer range in awhile.  But is the previously thought more favorable NA later this month and early March now looking less likely?  I recall there was some discussion awhile back about a PV split, and being on our side of the hemisphere, with a good shot at a return to more blocking around that time period.  Not sure of the details though.  It doesn't seem like the Pac side is going to do much to become better.

i think there will be mini windows for winter weather. I dont think a cold or a warm pattern is going to lock in. Lot of variability.....perhaps we score once or twice

[Scarlet Pimpernel]

Just now, Ji said:

i think there will be mini windows for winter weather. I dont think a cold or a warm pattern is going to lock in. Lot of variability.....perhaps we score once or twice

Well, getting into the time of year when we typically don't "lock in" on any cold/warm setup so I guess that's not a surprise.  I still think we don't get shut out the remainder of the season, and perhaps not even the rest of this month.  A decent moderate event, maybe on the order of a SECS-MECS, would still have to be on the table I'd like to believe, between now and early-mid March.  And perhaps a second event of some sort too if lucky.

[osfan24]

53 minutes ago, Ji said:

DT is ending winter based on the GFS MJO that takes it strongly into 4,5,6

meanwhile Euro loves the non impact neutral circle

Kinda weird since he would just regurgitate anything the Euro spits out.

[bncho]

3 hours ago, CAPE said:

Not enthused about this storm potential overall, but given the 6z run and that 12z was close- it just missed a phase(occurs too late offshore) and so off the coast the primary shortwave goes without gaining enough latitude. Main takeaway even with a miss at 12z, the best physics based model we have access to thinks its cold enough to snow in much of the region given a strong LP and track to our south, at least for now.

what does that that insinuate? there are better models out there that aren't available to us?

[CAPE]

6 minutes ago, bncho said:

what does that that insinuate? there are better models out there that aren't available to us?

No. Some prefer the AI models(also accessible). They aren't physics based in the traditional sense. So I am referring to the 'traditional' model guidance. Euro imo is superior to GFS, CMC, etc.

[cbmclean]

Some background on AI models.  https://x.com/i/status/2021333729088585882

[Ji]

Yeah its actually 'caving" a bit to the GEFS, which hasn't been as enthusiastic about the favorable look in the NA or the western trough weakening/progressing eastward after the 20th. We shall see.

And we back

[CAPE]

@Ji

Unlike the 6z run yesterday which had a perfect phase with the NS vorticity digging southward in behind the SS energy at the right time, the latest 6z run has a 'bad' phase. That NS piece is strong and gets involved too late, but rapidly intensifies what was a weak surface low, and its initially too close to the coast.

Next panel-

 

[CAPE]

The other problem with this run is, where's the 50-50 low? If it were in place, as that low strengthens and moves off the coast a bit it would probably snow.

[CAPE]

The 0z CMC is pretty much what we want- the 50-50 low is strong and somewhat displaced southward, locking in HP to the north. There is no phase and the developing coastal low is relatively weak, but good enough and the track is close to ideal.

[psuhoffman]

We still have a thread the needle option for PD.  It's actually pretty simple...strip away the mumbo jump technical stuff and we basically need a more amplified wave that takes the perfect track.  That's it.  Maximize dynamic cooling with a marginal airmass, perfect track to get heavy precip without any SE flow.  Too weak and its rain.  Too far north and its rain.  We need both the track and the amplitude of the wave to be perfect.  It's not complicated...but also not likely, but we're dealing with a marginal setup so we need everything to break out way.  Time to get lucky!  

Long range... I was optimistic 2 days ago, but that was based on the EPS/GEPS look in the long range...I was tossing the GEFS...well because...its been hot garbage for a long time.  Unfortunately everything has moved towards it the last 48 hours.  It's not necessarily the absolute worse look...the Atlantic is still workable...the pacific is bad but its not the absolute worse...it would only take some slight adjustments here and there to turn it into a good enough look and adjustments that are well within likely errors...but of course those errors could be the other way and it ends up a total shutout look and winter is over.  We will see.  

We need the NAO to trend a little more negative, we need that WPO ridge to extend over the top and put some pressure on that AK vortex.  Those two things would take the current look the end of Feb and make it a lot more workable.  

[psuhoffman]

Something I pointed out in the other thread...the 12z UK misses south, but it's closer to what we want...the storm trended north AND the thermal profile trended colder, such that had the storm been slightly more amplified it would have been snow across our area.  It just slides south...but it was a win in my book because we got one of the two factors we need...cold, and it got closer with the track of the storm.  

Some are acting like this is 48 hours out.  It's still 5 days away...time for trends and things to reverse and change a bit.  It's still close enough...its a long shot...we need a lot to go right...perfect track and max out a very marginal airmass but it's not time to close the door on it completely yet.  As long as expectations are in check and understood its a long shot.  

[CAPE]

This period doesn't look quite as good as it did a few days ago, but guidance is hinting at a few chances for wintery weather. Still have a developing -WPO and a decent NA look with a modestly -NAO and tendency for lower heights in the 50-50 region. Yes the trough out west is not ideal, but also not a death knell given the other h5 features. Still looks like a somewhat colder regime is in the works based on the HL upper level flow.