SnowGoose69

Also the PNA is likely to go + in that period, at least historically I think 95% of -EPO/-PNA E QBO Decembers had a +PNA January

Would not surprise me if 12/20-1/20 is really the period where it happens and 12/1-12/20 ends up normal or not overly cold.

One notable thing today is a -NAO, albeit a weak one showing up at the end of all ensemble runs. It makes a difference for sure, even if its just -1 if its far enough west as far as flattening the SE ridge component

The classic S-N moving overrunning event...the models even today underestimate those events here, especially from central LI westward though the Euro did well it was somewhat ignored in favor of the the NAM/GFS.

Yeah that ridge is way too far west on the 06z GEFS and 00z EPS/GEPS. The GEPS has what seems like maybe a broader PV that is more south which is why its not as bad. The SER is likely underdone if the EPO ridge is going to be that far west

01-02 was largely positive too. The problem was more just a terrible Pacific or AK pattern in both winters than it was the PNA. The NAO/AO were also largely positive except late December 01

Its common in the TNH pattern...93-94, 14-15 winters saw the -AO/+NAO often.

The good news is that GEFS/GEPS have kind of been destroying the EPS the last 4-6 winters for the most part with the post D10 evolutions involving the pattern due to them seeming to handle PAC issues better. Both of those show markedly faster transitions for those in the E in late Nov than the EPS which is going much more -PNA and SE ridge.

You’d think getting another mod strong one isn’t too likely. That would make 3 of the last 4 with only 18-19 not being strong or mod

People don't realize though that many significant snow events had a -PNA

I want to say those are "Normalized" or re-calculated in some way. I've seen the -1.3 mentioned by others too.

Seems the EPS/GEFS today may have killed it more too. I'm not sure if that is why today we've seen a trend towards less ridging in the E after D10 somewhat. A less potent run through 6 late and 7 might result in that.

925 winds for the metro are 44-49kts from 03-11z or so, sustained on MOS is around 30...if this was day time I'd be worried about mixing to 900 or 875 with gusts of 50kts but I think we might be only 42-44

Thankfully due to La Nina strength we can probably toss both 88 and 99. I think both those years also had W QBOs and W or CNTRL based La Ninas

Good thing peak winds at 900-925 occur when its dark, if this came through 12-18 hours later I think some gusts over 50 would be possible.