Stormchaserchuck1

These peaks in high temps around the edges of Winter are a little concerning for annual snow/cold, imo. 1/26/2024, Washington DC hit 80F.. that was the first time it ever did 80s late Nov - late February.. crushed it by a month! Do we hit 90F in DC sometime 4/4-7? 80F this Saturday. October and November have had 80s lately. March 2012 was an interesting turn, as many places in the Mid-Atlantic hit 90F. Since then overall snowfall has been down 2012-2025.

In March the NAO correlated warmer.. March pretty much neutralized the cold anomalies from DJF on the 30-year average, I guess saving my Winter forecast, but this Pacific-Atlantic correlation of +NAO/+PNA/-EPO and -NAO/-PNA/+EPO continues to hit. I saw it happen many times this Winter, when one index would shift, they all would shift.. I've estimated about a 0.40 correlation in the pattern since 2019, and 0.30 correlation since 2013. Also if you look at Europe's warming trend over the last few decades it's incredible! It's not like the US where there was snow 2009-2016, then not 2016-2024, etc.. it's a straight line down in places like Germany. That's because the Winter NAO has been positive since 2011-2012. 85% of the time since then! Say what you want about a warm US pattern despite -epo/+pna/-ao this year, but the NAO was very positive and that was a warm Winter variable!

It was really amazing to see the grass green up after those 2 good rains we had.. it was brown before. Hopefully we don't continue the pattern of last Summer, where the cap was breaking for nothing.. it was hot and humid, and no thunderstorms!

I can see some deep hurricanes this year.. Since the Winter we have been trending toward deeper/stronger low pressures in the mid-latitudes. There have been several 970s/980s mb lows. From 2020-2023, we saw a lot of mid latitude high pressures, so this is a trend in the other direction that really started in 2024. Will be interesting to see if it correlates into the tropics for Hurricane season. I was just responding to Barry, saying that we saw an expansion of the Hadley Cell, and more global high pressure systems, especially 2020-2023, but really since 1998. I don't know what the correlation with west-Pacific activity and the PNA is, but it might be a lower. It's this ENSO-dominated pattern that I'm talking about: High pressure in the Pacific might have kept activity down there. I'm not completely sure on that though. Now we have more low pressure.. this started in 2024 actually when the NAO was going severe positive many times May-Sept I wouldn't be surprised if we see an uptick of activity globally this year.... although I don't know why the difference for the last 30 years is so significant. I think current patterns continue to favor more Atlantic activity relative to the globe.

Kind of a wide range, but a lot of recent years are probably good analogs. I guess weed out the El Nino's and La Nina's. In the last 30 years though, global ACE is 70% of normal, while Atlantic ACE is something like 185% (and Atlantic is included in global number!). So although warm Atlantic SSTs and no El Nino may make some want to go aggressive, it's important to remember that globally more storms are not correlating with global warming over the last few decades..

ENSO models going near Neutral for the season.. We saw a major warming trend a few weeks ago, but that since waned big time: ENSO Subsurface is still negative.. so Neutral continues to be highest probability for the coming season... difference since 1995 is: ~20 NS La Nina, ~16 NS Neutral, ~12 NS El Nino.

Washington DC could make a run at or above 90F sometime around 4/4-7. It's amazing how forecasted long range -NAO tendency (March Stratosphere warming +time "downwelled") has run so warm in the East over the last few years. We had the warmest winter on record last year (23-24) with 4 separate Stratosphere warming events. -NAO potential at Day 15+ has almost always run with higher temps in the eastern, US, to verification time lately. That's why last Summer I was seeing +NAO potential for this Winter (24-25) as possibly a cold signal.. and it was! It often linked up with -EPO/+PNA/-AO!

With the Western US ridge really overperforming today (Portland almost hit 80*), Models really trended warmer in the medium range for the US, with that being initialized. Really amped this +NAO/+EPO pattern, maybe something near 90* around here isn't so far away. Apr 4-7 looks warm, if not hot.

If you remember, we had record warm SSTs across the Atlantic early last Hurricane season. I made that chart in February 2024 I think, and it was smoothed out, so the cutoff had to be 2023. But if you include last year, it would look like this:

For the 777th post, I'll say it's going to be 77* on April 7th. https://ibb.co/pjWYBwg9

That's just the Gulf Stream shifted a little south.

In other news, we continue to get warm US conditions in warm Stratosphere, and cold conditions in cold Stratosphere. You would say that makes sense, but it's main effect at the surface is AO/NAO. The NAO has a 0.5 temperature correlation in the eastern 2/3 of the US.. negative (warm Stratosphere +time) being cold, and positive (cold Stratosphere 0-time) being warm. Last Winter we had the warmest Winter on record for CONUS and it was during 4 Stratosphere warmings. The mean for the Winter was +500dm at 10mb. This Winter the opposite occurred, -500dm 10mb, but now after this March Stratosphere warming, in the allotted time where it's suppose to have NAO correlation, we have a major SE ridge signal on models, and possibly 80s. Another point is this -NAO correlation with SE ridge after the coldest day of the year (Jan 27th). For the last few years, the NAO has anomalously low correlation to it's usual tendencies in the late Winter/early Spring. I've found that even "potential -NAO events" (like a "downwelled" Stratosphere warming, or MJO wave cycle) have occurred with a flexed SE ridge in that time.

The AMO is still near the high peak of its positive cycle. For now, it's not in a descending state, it's sustaining or slightly continuing to increase. There is an overlap between the AMO and NAO. When the NAO is positive there is a -0.3 correlation to Atlantic SSTs. This is what happened last Summer - it wasn't that we were cooling because of an oncoming -AMO state, it was cooling because we had a near record +NAO occurring. If you think we will see more +NAO in the future, associated with Solar Max, that could be a cooler AMO.. It's around the timeframe now where decadal states have shifted, but I just don't see the "first Wave down" happening yet. Here is a chart going through 2023 of the current +phase

Nice SE ridge showing up on models April 5-7. We could break the 80s sometime around those days.

+PNA has really correlated with cold this year! It's underrated. That's what we need going forward (next Winter).

I can definitely see the strongest ridge being over the west coast this Summer.

Close to some flurries here! Hopefully this cooler trend associated with +PNA carries into next Winter.

Surprised no one mentioned the 18z GFS snows on us like 6 different times. It probably won't happen but the Stratosphere warming occurring now is going to create some more neutral conditions toward the end of the month to possibly keep us cooler.

^We were a -NAO away from having a good Winter pattern, it would have pushed the mean trough SW. Instead we had +NAO (SLP difference in the N. Atlantic between the Azores and south of Iceland), and it kept everything progressive. It's a shame we had -60dm 50/50 low, favorable Pacific, and really so little snow.. although places down south had average.

^I was pointing out in the Fall that 1955 was the only PDO analog that was close to our Fall PDO. That was interesting, because 55-56 was a cold Dec-Jan in the eastern 2/3 despite record neg PDO, then a warmer Feb. March isn't a match though. But for DJF, the 55-56 analog did come close to this year.

18z GEFS has a lot of "downwelled warmth" from the Stratsphere warming Days 10+ north of 60N in the northern hemisphere. That kind of a signal should correlate with at least a weak -NAO.

Nino 3.4 has been on one heck of a warming trend.. made it up to +0.3, then finally down for the first day in a while today.

This is the start of a legit warming btw

6 months of bare trees for 10" of snow? 3 months of cold for 10" of snow? I'm going with a "D". The positive was having snowcover through most of January though, and it did flurry or more 19 times (mostly in Dec and Jan).

-NAO may continue into the 2nd week of April..