40/70 Benchmark

This times 1,000,000.

Could even get delayed a bit, but will happen...

Edge of my seat...

Pacific Trough Regime 1, January Winter Storm Threats 0 Forecast Early January Pacific Trough Regime Comes Into Focus Guidance Adjusts Accordingly Next Week Last week Eastern Mass Weather discussed how the uncoupling of the intensifying stratospheric polar vortex from the troposphere was allowing for the unanticipated development of a potent west-based negative NAO block. This was a crucial part of the forecast because it was instrumental in allowing forecast guidance to model a potential major east coast snow storm during a period in early January, which represented a deviation from the winter outlook issued last fall that called for a mild, Pacific trough type of pattern in place during this interval. However, guidance has since shifted rather dramatically towards the type of pattern favored for the first half of January, which replaces the storm threat with warm up. Thereafter, the forecast for the balance of January remains unchanged. Colder Turn Around Mid-Month The pattern should remain mild overall through at least the 10th, with any significant snow threats likely related to northern New England, as the MJO tries to emerge into the MC from the neutral circle. However, the pattern will beginning to enter a state of transition, as heights begin to build on the west coast. The MJO will begin to play more of a role towards mid-month, as it enters phase 7 and constructively interferes with strengthening west coast ridging. Note the support for the EPO and WPO to both return negative by mid month. Although support for the development of a +PNA is more tepid, this is likely to correct more aggressively over the course of the next week. Ultimately the culmination of these changes is a full-fledged +TNH pattern that should ensue by approximately January 20th, which will include a slew of moderate winter storms targeting the interior. It will be important not to allow the more active winter pattern to divert attention away from the stratosphere, which will likely take center stage in February. Please stay tuned for more updates this month-

https://easternmassweather.blogspot.com/2026/01/pacific-trough-regime-1-january-winter.html

https://easternmassweather.blogspot.com/2026/01/pacific-trough-regime-1-january-winter.html

See-Mour Snow in Methuen than CT....'bout time.

I like early Feb...then flips warm while strat does it's thing.

Theoretically speaking, I agree....but I would be stunned if ends up solidly negative.

It depends...the issue isn't as binary as the question implies. It depends on the pattern and location....generally speaking, +PNA is beneficial anywhere on the east for cold, phase potential....but in the northeast, sometimes a more neutral or even negative PNA is preferred if there is a major NAO block....below about 40N, you always want a +PNA.

I think there is a recency bias for folks to see a deep, cavernous trough on the west coast, and then just kind of throw their hands up and succumb to the prevailing theme of the decade....but don't forget, that was in fact abandoned last season, regardless of the lack of snow around these parts.

I still say that the +PNA will win the month. I would be careful about buying the deep -PNA as much as I was the -NAO...I bet we see that go "poof" in like fashion.

Yes, this is why often the big arctic blasts in these shoot down the center of the country and we get more pedestrian cold.

+TNH is often +PNA, but not always.....has the PV near Hudson Bay.

IDK...I think the +TNH regime is clear as day. I agree the details need to be worked out, but I don't think there is much ambiguity concerning the larger scale pattern.

Late January will be crucial...if the gradient sets up just north of me, as it has so often and as @jbenedet indicated, then SNE is most definitely cooked in terms of seasonal totals. Wolfie, please put the fangs away...that doesn't preclude a great stretch, but all I'm saying is that climo snowfall is by the boards for SNE if latter January screw us. Maybe not for select areas in CT that got 8.5" last week-

I could totally see it taking somewhat longer than mid-month...perfectly reasonable possibility, especially if Canada gets really flushed.

Great post....only cautionary note that I would add is that January 2022 +TNH interval worked out south of that line.

This is why you incorporate the QBO and solar cycle into analogs. I think my progression has been good so far....only blemish is the severe -WPO making December colder than I thought....but moving forward, I was confident in latter January +TNH last fall, and still am now.

I'm pretty confident that any huge PV infiltration would knife down through the center of the country, anyway.

Last season I bailed after that big January threat failed. We has one decent stretch in early Feb and that was it. I felt like March was a lost cause dating back to the fall, and I was absolutely correct. It was.

I don't know, ask someone who think it's over-

I think "by January 12th" is aggressive, anyway.

I think 2014/2022/2025 analogs will play a role in January and February, along with 2001...not a bad cast.

Main difference between this year and 2018 is I think there will be much more of a +TNH element to this season to partially shield us from stronger PV intervals...this is what I think saves us for at least the start of February due to the carry over from the second half of January. The cold will be there after the flushing next week. It will get scary with the PAC jet firing and all, but it's temporary.