psuhoffman

@CAPE @WxUSAF EPS is a carbon copy of the GEFS.

1987 was an analog showing up a lot in the ncep list and the one big snow we got in Feb that year was 50 the day before and after...but it snowed 12-20” with temps around 33-34 degrees in between lol.

This is NOT the same as waiting for a late save in March. Yea it sucks to wait until later January but honestly this is our climo MO. And frankly if we want to pick the absolute best time to maximize the probabilities of taking advantage of blocking and cold late January into February is it!

It has begun...

Oh yea but I’m sort of hoping we pull that card. I said back in the fall I expected this winter to be pretty awful and the only thing I saw that could save us was if we got blocking. I still feel that way. For my area. You have a lot more ways to make things work up here. I’m just pointing out “if” we do get a west -NAO regime the general pac look we’ve had and look to have can work out. Lots of ifs and buts in there though.

Ideally yes. The near record cyclone that blasts in there this week is a killer. But I’m referencing where the vortex has been centered most of winter so far and where long range guidance suggests it pulls back to after the next 10-12 days. We can do ok with lower heights near the Bering so long as a massive vortex isn’t centered there. the look mid January across guidance right now is pretty close to the composite of our biggest snow years and some of our big dog storms. But if you’re talking about why it’s warm the next 12 days or so yes! I was looking ahead. Btw miss your input in the mid Atlantic thread. Please pop in when we have a threat worth talking about.

@WxUSAF this is about as big a “real” ridge signature as I think you will ever see on a day 16 prog. Even a hint of a 50/50 sig.

@CAPE the new gefs is perfect Imo. This is exactly where we want that N PAC trough. This pumps heights into western N America and gets the ridge axis along the west coast. That’s even too far west without blocking but with a -NAO that promotes the broad trough look under the block we want. Pull that Pac trough any further west though and the ridge pulls back into the PAC and that broad trough will split with the cold dumping into the west and a SE ridge will pop. Give me exactly what the GEFS is showing now. It’s not being pushed back in time so far either. Today actually sped up the progression by about a day.

He isn’t wrong for the mid Atlantic though. I’ve run similar studies of our big snow events down here and our best big snow look often has a trough in the N PAC along with a west based NAO block. It’s a big if, but if we do develop a west based NAO block the pac is just fine. Otherwise it’s crap.

Long range gefs is seeing a bit more of a 50/50 signature. That’s one way this could flip colder fast. Get enough of that and it will fight the eastern ridge.

I guess 2020 didn’t end all bad

This is just for fun but the end of the GFS run is how I see our best chance of getting snow. Something like this. It retrogrades the blocking into Canada. Same PAC look with the WPO EPO vortex sensing systems into the west. Which leads to this... that system is trying to cut...but it’s not going too. Look at all the confluence to our north. There is a 50/50 stuck just off the screen and there are lobes rotating around, one is just over top us. The 850s look iffy at a glance but look at all the dry air And as the system approaches the 850s are already crashing in TN and GA when the precip hits the dry air. All that +1 air over NC will end up below 0 once it saturates and has to advent north before we would go to rain. This was an incoming snow event. It may have been a snow to ice to rain event...but it was at least a decent frozen event oncoming. Same crap pac. Being offset by the blocking. That’s what history says should happen in that pattern.

I actually have thought for a while that storm is likely to trend more amplified...but I also think think it ends up mostly a rainstorm so I haven’t given it much thought.

Maybe not but a central pac ridge pattern won’t be any better.

Sorry...I took a lot of heat for that post (@Mersky)and I totally understand why...but it was 100% accurate. I guess I’m not a stick your head in the sand kinda guy.

We don’t have a west based block now. The attempt at that this week failed. The storms that were supposed to assist to retrograde the WAR ended to cutting so far west the instead ended up pressing the ridge east more. The one time in December the AO really ranked we did get cold enough and a legit snow threat. Details didn’t work out but I’ll take that over playing with the fire if that WPO vortex vacates. Given where the tropical pac forcing is...if we lose that n pac vortex I don’t think we get the PNA everyone wants. My guess is we pop a central pac ridge western trough.

I’m of the mind it doesn’t need to improve if we get a west based block. Actually is the N PAC trough vacates and we get a ridge there that’s a worse look with a -NAO.

Now you’re getting really specific but yes ideal pna ridge axis is around Idaho

I think there is some confusion with what an EPO is. An extremely east based EPO coupled with a PNA ridge centered along the western US into western Canada is a great thing. But that’s not a typical EPO and I doubt that’s in the cards. A typical EPO ridge extending from the central PAC into AK is too far west and dumps the cold into the western US. Those both fall into “EPO” but for our purposes are totally different patterns. One good one bad...both under one index.

@CAPE everyone is mad at that north Pac trough but we’ve had some epic snowfall regimes with that look. 1996, 2003, 2010. And that trough is keeping the central pac ridge suppressed. That ridge (remember my soul crushing post last December)is the single biggest snow hope destroyer there is. It can even destroy a -NAO! We have occasionally overcome a pac ridge with a -NAO like feb 2006 but it was still a warm month and if they one storm hadn’t worked out we would have wasted a beautiful block because of that pac ridge. My number one “want” is keep that central pac ridge away. This look on the long range GEFS is getting dangerous. Retrograde that WPO vortex anymore and that pac ridge is going to go ape and we will be fighting a SE ridge even with a block! A perfect pac isn’t in the cards. Getting some huge stable PNA ridge just is unlikely with the current forcing. So imo a WPO vortex is by far the lesser of 2 evils v a central pac EPO ridge that dumps cold into the west while we ridge out! I don’t care about cold it it’s on the other side of the country!!!

Maybe. But sometimes with a -NAO a EPO ridge dumps the cold into the west unless it’s an east based EpO that extremes into Canada. If it’s a central pac EPO ridge into AK that’s actually a bad sign. It’s one of the few NAO killers.

Lol that’s super rare. Typically a ridge into AK and you get a trough dumped further west then that. Most of the time to get that wavelength spacing to work requires a -NAO also.

Yea I think we’re making slightly different points. I’m saying I hope that isn’t true because of an EPO is the best way to get snow in the new normal...the new normal is going to suck.