Stormchaserchuck1

We could have a buckled mid latitude jet though.. if that were the case you could say, 1/3 odds, 1/2 odds or whatever.. but it's not an ideal jet stream situation we have as waves west and east of the storm are progressive. Just makes the timing needing to be just right.

0z GFS and 6z NAM completely different from each other at 84hr.. GFS dug part of the Polar Jet a lot further SW.. NAM has less phasing. NAM not the best model though.

It's not about wave spacing, it's about having a nearly perfectly timed wave to get the high outcome. That map shows that there's a lot of moisture though. I just think the high potential is capped, given the larger 500mb pattern.

True, but it is about "threading the needle" a little bit, as we need a perfectly timed wave, which models showed tonight, but I'm just saying there is more potential variance than normal between now and the event.. It's not being held constant by any particular thing in the upper latitudes, except the remains of the -AO block over Canada.

This moisture sure is pretty though

I'm a bit skeptical of a big one riding on the heals of this.. This is at your -5 AO Don't get me wrong the Pacific turns favorable.. -EPO/+PNA is definitely what we want, but I think a 4-10" event is more likely than 12-20". I can see something moving more W->E vs S->N. The pattern is actually pretty progressive, it's just a matter of really good timing, having a trough right under the Canadian block on models tonight. They sharpened the trough, but not necessarily the N. Hemisphere fundamentals. I mean it could happen like that, but there's more margin of error imo, and less high potential too without an east-pos-PNA and further SW 50/50 low. Don't get me wrong, I think there could be a snowstorm. But I'm not buying the MECS just yet.

I understand what you're saying, just know that models have trended toward a warmer high latitude pattern after the 20-22 storm.. They have been bad in the Day 10+ range, but right now I think it's looking like more of a rain threat. Maybe the MJO tendency will overpower.. we'll see.

A trough off the west coast in the NE Pacific would look attractive. Our average temp is in the low to mid 40s.. we need more than flipping the map.

Yeah.. I think its potential is somewhat capped though.. expect more of a progressive wave vs Miller A MECS. But it could trend north..

Block isn't super strong.. +NAO keeps the flow progressive We still can get a snow event out of it though

Need everything to slow down for that to happen, and it's somewhat of a progressive pattern..

CPC apparently changed their reading some time ago.. and it's ... not even really close. There was a time in September I think too where there was N. Pacific High pressure and they said it was like a +2.5 PNA lol. I don't know.. someone said they keep the old calculation on another website, and that one has been -PNA for the last month. You can see the clear Pacific-North-American 3 wave pattern in the map I posted. It does run into the EPO domain a little, but is mostly south of Alaska and over the Ocean.. a clear -PNA. This also isn't going to be close to one of the most +PNA Winter's on record.. the 500mb map isn't like that at all. I just don't know how the CPC has +PNA in that time if there is a string of High pressures from the Gulf of Alaska to NE Asia! I don't know what to say... maybe it's better just to look at 500mb or SLP maps and make your own call. They also had many +NAO's when there was a Greenland block lately too.. maybe they use something that is completely independent from H5? I don't know..

Good research Larry, like always, but this is not +PNA

I stand corrected saying the PNA has been positive all Winter yesterday. There is something wrong with the CPC's methodology of calculating.. this is a 1-month period of -PNA.. I don't care that the CPC says it was +pna. It's not going to actually be one of the most +PNA Winter's on record..

The pattern is ok... you guys aren't hearing me that, that's not a 50/50 low.. it's too far NE and actually a +NAO. Now +NAO has higher precip correlation, so when the Pacific pattern works you can get an overrunning storm.. that's probably what we'll get, but not a Miller A without south-of-Alaska low 500mb and sustained 50/50 low. Beyond there, I got weenied 10 times for saying this last night... but it's not an impressive cold pattern. The EPO looks to go positive for a few days. The next "threat" after the 20-22, probably right now looks like rain. @psuhoffman The AO pattern has its highest snow correlation when it's deeply negative.. not coming back to neutral or positive. The NAO is what you want to see go back to neutral because its negative phase is so dry... but we are missing a -5 AO here with 2 rainstorms. After that, when the AO goes back to neutral/positive, it's not a favorable pattern for MECS anymore! I know your research says lag, but besides the 20-22 storm, it's not looking like a favorable period, mostly because of lack of deep cold (because by that time it's not -AO)! The index regions do correlate the highest with US temps at Days 0 to +1.

My Christmas tree is still up! One year I left it up until July. Actually 2 years. but July is the record.

Uh oh.. 1st run showing it, and GFS ensembles have not been great lately, but Days 10-13 have a +WPO/+NAO pattern.. pretty strong. Going to flood the CONUS with warm air after the 20-22 storm if the run verifies verbatim. It does shift back to +PNA days 13+ though

Was there a 1001mb low in 1983?

No going back to what's behind us. that goes for all of, you

It has been a Weak Nina-like STJ

Nino's have correlated with +EPO lately. Actually, the NPH (North Pacific High) is its main correlated region.. last Winter it did pop a -NPH, which is typical of +ENSO El Nino's can be very warm, and La Nina's can be very cold.. but we can get big snowstorms in El Nino yeah West-based El Nino, focused near the dateline is the better potential scenario.

It was record breaking the last 7 years, especially in Feb-March, until this year. Big flip this year. Strongest non-Nino +PNA probably since 00-01. 2 weeks ago the GFS ensemble mean had a +300dm -PNA in the long range.. they didn't even come close to verifying.. it's still +pna

PNA hasn't gone below -0.1 a single day since Dec 1st.. and that looks to continue at least through March 1

The 90N block maxes out in the next 1-3 days, at +500dm. After then the AO loses its strength. It becomes about the Pacific moving into a more favorable pattern. The MJO is more about what H5 it's correlating with.. but this stuff at Day +0-3 is modeled well right now.. it's not something that is over the modeled 500mb pattern. It just sounds like you like +PNA over -AO... which is fine, but I think a Polar block maxing out and producing 2 rainstorms at its max without a -PNA pattern or anything like that is kind of disappointing. Like I said, AO is more about what it produces as it goes strong, not so much when it comes out of that max like the NAO.

With that south-based +NAO, I wouldn't be surprised if it trends wetter in the coming days. Also watch to see if that -AO holds strong with a -epo/+pna Pacific.. it might come a little north. AO is like -4 for the storm as modeled right now. Here is precip correlation to south-based +NAO in February https://postimg.cc/5H4Ty09s