psuhoffman

I see mixed signals for Feb. Tropical convection (if you extrapolate) isn’t ideal but it isn’t in the worst spot either and it’s been a muted driver so far. I also find it odd that some who dismiss a good look on guidance say 10-15 totally accept a bad look day 25 lol. Some people keep misidentifying normal reversion towards mean at long leads as a sign the -AO/NAO is breaking down. That’s been going on since December. Even now after hints it was breaking long range earlier this week there are signs on the eps and geps that blocking reloads AGAIN into Feb after this retrograding block episode. GEFS is neutral. It lingers the -AO/NAO. I kind of favor a continued high latitude blocking regime. There was another PV split yesterday! The effects of the original SSW event are just coupling with the tpv now. And there are hints at further strat weakening next week. This has the feel of a full season -AO year. That said other factors could continue to mute its effectiveness at delivering cold/snow. But if a decent but flawed pattern is ever going to work February is the time. The picture is murky Imo. Definitive calls for February seem premature.

If a Rex block retrograding from Greenland to Baffin along with a -epo doesn’t work then frankly I’m out of ideas how to countermand the pac jet.

What makes you so sure tropical convection centers near the MC in Feb? Most evidence I see has the most dominant signal in the western pacific. Not as far east as ideal (probably more phase 6/7) but not as hostile as the MC. That and the MJO has been a non factor so far.

There is kinda a catch 22 with that first wave. There isn’t much cold in front. So if it’s not suppressed and it pumps any ridge and rides the boundary it goes north of us. But if it is suppressed it gets squashed. Not saying it can’t be a hit but it’s a very delicate balance because there isn’t enough cold in place ahead of the wave. This isn’t an amplifying coastal type setup. For a west to east boundary wave to work it’s much easier with good cold in front. Let’s see what the eps has to say about the 10-15 period. 12z eps liked it and gefs really hit that time 18z and again 0z. Gefs 5 day mean day 10-15

well...those that wanted cold check out the Para. Not a drop or flake of any precip after tomorrow...dry as a bone for 15 days...but damn cold lol. WAY too much of a good thing. Huge block but develops a TPV vortex just to our northeast under the block and it sits there forever just squashing everything. Nothing even comes close...not even NC...its too suppressed for anything to get east of the MS. Now that would be an epic way to fail after we couldn't buy any cold air the first 6 weeks of winter...to waste a block because its too cold.

I get the frustration...but we have had some hits mixed in lately...the euro snowed on us like 4 straight runs actually. The GFS and para had a few runs with a hit day 10-15 and the ICON just had some snow. We just have not had any consistency with one of these waves yet...guidance is all over shotgun style on how they play out. I still think the progression favors a further south track after the wave on the 22nd, if there even is a wave on the 22nd. It's possible the southern wave shears out and the northern wave stays to our north...and its not much of anything. That is one option because there is so much ridging in front...but then with a sudden wall in the way from the blocking. If you really want to look for something "exciting" I have noticed the trough in the west continues to retrograde, in response to the pac ridge retrogression...and by around day 15 its SOOOOO close to pulling back enough to really dump a huge trough into the east under the block. And this time because there is a ridge in the WPO not a long trough across the whole north pacific...there wouldn't be a raging pac jet blasting into north america. Imagine...a poleward ridge west of alaska to get cold into N America...then a trough off the west coast to get a PNA ridge...then huge trough under the block in the east...going into February. Might as well dream big right? This crap has to end sometime...why not end with a bang.

Give it a few days. It will be a deep south storm Every wave we are tracking is still 7+ days away... a range where there will be significant changes on every op run. But you are tracking them like every little detail on the run is live or die as if its 24 hours away. That very first wave around the 22nd is maybe a day or so away from getting to a range where we might start to get some clarity. But I was never that optimistic on that one anyways. But you would do better to let the full run's come in and then just get a sense for overall trends based on the ensembles rather then getting twisted around by the flip flops of each op run.

Given where the block is by then...I would worry more about suppressed then a cutter like the GFS shows.

The indexes don’t mean much in March with short wavelengths ETA: they do if you want a sustained pattern like March 1960 or 2018 but a fluke storm can happen in almost any pattern the way waves can dig and cut off that time of year.

I like their apple pie

If we weren’t in a pandemic and I didn’t have a family I would seriously be on my way to NC right now to get a chicken cheddar biscuit.

We’re in the worst snow drought IN HISTORY. This is like if you’re starving and someone offers you a bucket of chicken and they’re like “I’m not eating that unless I get a biscuit”.

Btw weeks ago we laughed about the weeklies showing a great pattern but no snow. Well.....just saying if we’re going to blast the long range guidance when it’s wrong we need to acknowledge when it nails something

The weekly ensemble members are not run at high resolution. They won’t estimate things like meso banding and that’s 10-1 which if you and I get a flush hit you know ratios would be higher. The gradient to the NW of 95 is NEVER as sharp as reality would be on those because a lot of what causes our enhanced totals are meso features (upslope and higher ratios and banding) a low res ensemble member won’t see. Also a 50 member ensemble will always skew towards the mean by outlier members. It works both ways. I would say the same if the pattern looked awful and it showed a 3-4” mean. Thats actually a shutout look. Just a few outliers skewing towards the mean. What I’m saying is it’s the axis and anomaly that matters more then the total. Snow maps aren’t even close to the best way to analyze the pattern but you can take hints from them if you know how to interpret them.

@CAPE this ones for you...euro weekly control. I get fringed up here! Fwiw (not much) the euro weeklies had their best run wrt snow mean all winter. Clearly above climo for the period, especially along 95. It’s not shocking...the general H5 looks workable right through Feb. -NAO suppressed SE ridge pattern in feb could work. control Mean

Para did come really close to a monster storm around the 25 but bombs just off the coast.

Wait till you see the para gfs. Cutter. Suppressed suppressed suppressed cutter

It’s weird the Rex block is actually gone it’s just a -NAO ridge but it goes berserk with a vortex in the 50/50. It’s actually the flow under a block that creates the effect so that solution is even more suppressive

When he said the west coast, you thought he meant of THIS planet??

@CAPE of course the -AO will end sometime. Maybe it does finally flip in February but by then we had a -AO from late November straight for 11-12 weeks. The failure of the winter wouldn’t be that the AO was positive the last couple weeks imo. Lol

Yes but in November it said that was coming by mid December. Then in mid December it was January. Then late January. Now by mid February? Ok...

I’m sorry this is the AP course. The remedial class is down the hall.

They have tried to kill the -AO/NAO state all cold season just as guidance tried to weaken the +AO in previous winters. Part of that is reversion to mean at range. Part is guidance misidentifying a key driver. 2 years ago it was a nino that never coupled. This year is a Nina that’s being countermanded by other influences. ETA: point is I doubt it just flips. If we fail this winter we can’t blame the high latitudes. That might make a fail even more painful

Well one is getting it inside 300 hours. The genesis of the pattern is only 5/6 days out from there you can extrapolate... But also other factors. One being the pacific flow backing off which won’t destructively interfere as much. Another is more cold injected into the pattern. We did have pretty good (not as good) look up top the last 10 days but with no cold we wasted it. 3rd guidance often is too fast with a pattern progression both setting in and breaking down. Lastly the effects of the SSW are just starting to couple with the troposphere so increased blocking is supported. It could still fail. But those are reasons I have optimism.

@stormtracker you are right to be skeptical. I’m wrong plenty of times. But let me lay out why I think our opportunities increase the further into this pattern we get. And I feel confident not because the guidance shows this because this was the progression I started laying out days ago before it was as apparent as it is on todays EPS. I’m confident because the guidance is going towards what makes sense wrt how the pattern should progress. Let’s start with why that first wave around day 8 is going to have trouble staying snow despite the block. It’s about what happens before it. The genesis is day 4. The pac ridge (1) is going up and retrograding. It don’t look like much yet but the energy in western Canada and AK is digging into the west (2) in response. As that trough digs downstream once that trough in the east moves out there is nothing to stop a ridge from popping (3). The NAO block (4) is not yet in a spot to be helpful. Actually it’s really still just an extension of the WAR there. So let’s go out a few more days... Now the blocking is getting going. But even there is still centered just east of Greenland and it can’t go back in time and erase that ridge already in the east! It’s not that the block isn’t good but it’s too little too late. But keep in mind the location of key features there. Block just east of Greenland and 50/50 just NW of NF. Could that force a secondary south of us...yea but that ridge is a bit much and more problematic look at the airmass in front of that wave coming... Just being honest...all that ridging with a block just getting into ideal position and no cold in front...isn’t likely to end well. Not impossible but I’m not getting my hopes up. But now that the block is up and there is cold getting into N America as the pac flow finally relaxes look at the progression. With each wave more cold will bleed east under the block. So lets try this again a couple days later... At first glance it might seem that’s the same. But the ridge is flatter. And look at the key features. The blocking is now centered just WEST of Greenland. And the 50/50 is over NF. But most importantly look at the temps in front of the next wave... ok...that’s not Arctic but that’s much more workable. And look at the MSLP anomalies. They hint at exactly what I was looking for... And imo the wave AFTER that day 11 threat has an even better chance. Fast forward to 300 hours and we try again but... look how flat the ridge is that time...look at the location of the block and 50/50. And look at the temps in front this time... Now we’re cooking...the mslp is washed out by that range but the mean precip during that period hints at what is going on. so yes this all relies on certain things happening that may not happen. But it fits the pattern progression. I’m showing this because the EPS went to how the pattern should progress imo. If it does the wave around day 11 will have a better chance then day 8 and the wave around day 14 will have an even better chance. sorry for the war and peace post.