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Judah Cohen blog https://published.aer.com/aoblog/aoblog.html Plain Language Summary The widespread warmth across the Northern Hemisphere (NH) this past summer and now the fall has continued into October (see Figure). However, a series of stretched polar vortex (PV) this month has led to some, albeit modest cooling in Siberia, East Asia and to an even lesser extent far Eastern Canada and New England (see Figure). However, one last stretched PV will bring more intense cooling to Siberia and East Asia and yet again more modest cooling to far eastern Canada and New England (see Figures 3 and 6). Some blocking in the North Atlantic and near Scandinavia will also bring colder temperatures to Europe (see Figure 9). But all eyes then turn to a much larger disruption of the PV that is likely to have an important influence on NH weather late November into December.

He already busted last winter.

Our first state of the Nationwide Study is now complete. First up is the state of Pennsylvania. We will release one state per day over the next 47 days. For much more detail including study design, by decade breakdowns, county by county maps and breakdowns for all State Counties that compare actual vs NCEI trends for each state please go to https://chescowx.com/raw-vs-ncei-state-by-state/ If interested in seeing your state next up on the list please let me know and we will do our best to release that state within 2 days. Thanks again! The main finding for Pennsylvania is the actual readings show no warming at all since 1895! NCEI's published series shows significant warming. Averaging what Pennsylvania's observers actually recorded, county by county and weighted by county area, gives a flat statewide trend from 1895 to 2025 (-0.02 °F per decade, not significant). NCEI's published statewide series warms +0.17 °F per decade, about 2.2 °F in total. The two diverge at +0.19 °F per decade (p < 0.001). NCEI's series runs 1.5–1.8 °F below the actual readings in every decade from 1895 through the 1940s, about 1.0 °F below in the 1950s and 0.7 °F in the 1960s. It is within about 0.35 °F from the 1970s on. The short version NCEI's 67 counties add up to its statewide series. Weighting NCEI's county values by area reproduces its Pennsylvania statewide series within 0.03 °F in every year. Building the state from counties is therefore a like-for-like comparison. The actual readings show no significant statewide trend. They give -0.02 °F/decade (95% range -0.10 to +0.06). NCEI's series gives +0.17 (range +0.10 to +0.24). The ranges do not overlap. The two trend lines are significantly different. The gap between NCEI's statewide series and the actual readings grows at +0.19 °F per decade (95% range +0.15 to +0.22, p < 0.001), so NCEI's adjustments add a statistically significant amount of warming. County by county, NCEI's adjustments add significant warming to the trend in 25 of 43 counties (58%) and significant cooling in 0. NCEI cools the early record in nearly every county. From 1895 through the 1940s, NCEI's county series is cooler than the actual readings in 90–100% of counties in each decade, by a median of about −0.9 to −1.7 °F. The share is 77–81% in the 1950s–70s, about 53% in the 1980s and 1990s, and about 31–33% after 2000. Recent decades match. From 2000 on, the median county difference is about 0.0 °F. NCEI is cooler than the actual readings in 32% of county-decades and warmer in 41%. County verdicts flip toward warming. 43 counties have long enough raw records for a trend. In the actual readings, 8 (19%) show significant warming, 31 (72%) no significant trend, and 4 (9%) significant cooling. In NCEI's county series, 41 (95%) show significant warming and none show cooling. NCEI's trend is steeper in 42 of 43 counties; Philadelphia is the only exception. The 1930s lose their warmth. In the actual readings the 1930s average +0.9 °F against the 1991–2020 normal, the warmest decade before the 2020s. NCEI puts the 1930s at -0.7 °F. Chester County fits the pattern. The actual readings from Chester County's GHCN-Daily stations give -0.01 °F/decade (not significant), against +0.24 °F/decade (significant) for NCEI's Chester County series over the same years.

I wonder if he wished for a super nino for the big 40th, or maybe some humility

Silly people like Brett already have the winter over in October lmfao… so pathetic!

nope

@forkyforkMy mistake concerning underselling ENSO early on was being focused too much on periodicity given the magnitude of the 2023 event just 3 years ago, but upon gaining a more through appreciation for the impact that the solar cycle on ENSO, I now realize that it was 2023 that was the anomaly given that it occurred near solar max. This event is occurring right in the descending solar wheelhouse. My guess is the magnitude of 2023 was largely the result of CC in that it represented a failed effort to redistribute that warm pool eastward...if at first you don't succeed....

I still think one or possibly two events could workout later in February with a second ssw. Even 72/73 which was horrendous in NYC had a big one in the southern mid Atlantic. So there is definitely precedent. I think we get hung up on 97/98 too much. That winter everything just went wrong. .

https://paweatherplus.com/pennsylvania-winter-outlook-2026-2027/

we all make mistakes

Maybe its because the Mid Atlantic will see most of the storms. Jet stream will be aligned for them.

Everyone who puts themselves out there is going to miss...like he missed last year...some our transparent and honest with ourselves, others not so much.

Fingers crossed!

Don’t forget water temps have skyrocketed in the MDR in the last couple months. At the very least it’s setting up for a big season next year. .

drag 'em

Even if it couples, there is never any guarantee that the impact will be manifest in our little slice of the NH. Could just as easily be Europe or Siberia. Or even western NA. Those are reason why I'm usually underwhelmed by SSW pipe dreams in the middle of a dud January. This year though, it looks like we want to hope for it, because it might be the only way to avoid a tropical December a la 2015. And remember that for the December 2015 torch it took the majority of Jan 2016 to recover the NA thermal profile, and you guys were as far south as that recovery went as far as significant snow. I wouldn't place good odds on that happening again 10 years later.

I’m really surprised that a legit meteorologist would make such bold claims. 09/10 is about the worst analog possible. That was the winter of all time for the mid Atlantic and has no other comparison in the historical record. .

blew past that before midsummer. lol

haha