Stormchaserchuck1

Nino 1+2 finished March >+1. That actually rolls forward to a strong +PDO signal by the following Fall (although the signal could be because of blossoming El Nino events)

Cold will sometimes produce. Snowfall can be too localized for grand general analogs. Did you have any snow in March? Does Boston still have its <4" streak going?

ENSO subsurface continues to be cold in the central region, which at the very least favors ENSO Neutral this season. Last year I did research on the trend regarding different Hurricane season factors. Here's how ENSO subsurface has been leading surface events: Here's my post from last year which is a 1 year old, but you can still see the long term trends.. I think we had 18 Named Storms last year, 11 Hurricanes. In 1995, the AMO (Atlantic Multi-decadal Oscillation) index switched to positive, and since then it's been rising/still hasn't peaked. Atlantic Hurricane season activity is strongly correlated to the AMO, and Atlantic Hurricane season activity has also been in an upward incline since the 1995 AMO switch. Here is a smoothed graph of number of Tropical Storms by year: Since 1995, we have averaged the following number of storms per year in various ENSO states: El Nino (8 years): 12.5 TS, 5.4 Hurr, 2.5 MH Neutral (10 years): 16.4 TS, 8.2 Hurr, 3.8 MH La Nina (10 years): 17.9 TS, 9.2 Hurr, 4.2 MH In September 2022, the AMO peaked at an all time high of +0.662, and is still rising/in an inclining phase. I plotted monthly AMO numbers, up until the CPC last updated the dataset, which was January 2023: If you smooth out the index, it looks like a very clear rising phase is still underway: Since those AMO graphs, we had record +AMO last Summer, now it's cooled down to be cooler than the last 2 seasons, but still above the 30-year average. We are still on the general AMO trends. The Atlantic activity has been especially strong lately: - 4 of the last 5 years have had 18+ Named Storms - The average in the last 5 years is 20.5 Named Storms/year - 8 of the last 9 years have had 7+ Hurricanes - The average is 8.7 Hurricanes/year for the last 9 years With ENSO Neutral and slightly warm Atlantic SSTs, I'd put the over/under on this season at ~16 Named Storms, just based on long term trends. Remember, the rest of the globe has not been nearly as active as the Atlantic.

Well it's from +PNA. PDO-neutral is still not +PNA favorability, but we have seen a new trend of stronger +PNA episodes over the Winter which brought the PDO up. Rolled forward, it doesn't give a +PNA signal for the following Winter (+12 months) Per the CPC, it was the strongest +PNA Winter non-El Nino since 1950 as Gawx has researched. ^That is a +NOI signal though (high pressure off the west coast), which is a slight La Nina indicator Winter +PNA rolled forward is surprisingly a slight La Nina indicator for the following year, based on 63 years of data (It probably has to do with El Nino's typically switching)

-3c in the central-ENSO-subsurface.. it's not budging. The trends of surface warming through Feb and early March matched oncoming El Nino episodes, but that subsurface is still in Weak Nina range.. all last year it was around -3 to -4. Imo, that's more important than surface SSTs.

I found this interesting, a +NAO in March has a slightly cooler temp correlation in April (usually they all go in the same direction).

Thanks for doing it Roger. April DCA _ NYC _ BOS __ ORD _ ATL _ IAH __ DEN _ PHX _ SEA 1.7 1.8 1.6 1.2 2.1 1.6 2.1 2.7 1.0

Not going to hit 90 in that allotted time, but DC has had 3 straight days of 82+ here in March, making it the 4th warmest March on record. With the NAO being positive almost all of the time in the Winter (March will probably be >+1.00), the Pacific is what is needed for cold, but when the Pacific favorability shuts down, it torches.. DC hit 84F today.. a few days ago, it was expected to make it into the mid 70s today.

Looks like they want to repeat 2024-2025.. I wonder if back to back years have ever been so similar (except for ENSO)

Atlantic SSTA's are right near the 30-year average, cooler than the last few years. But the year-to-year makes a difference, as the subsurface does play a role in tropical systems. Because the last 2 years were record breaking warm, there is probably warmer subsurface water in the Atlantic relative to current SSTs. There is also a cold pool right off of Africa, that has a lite correlation with a cooler Atlantic during peak season, but the anomaly is weak right now so it's not a real good roll-forward.

CPC is actually going really aggressive on -NAO based cold from/after Stratosphere warming.

Stratosphere warming is finally correlating with -NAO on models.

SOI has been positive every day for more than a month now. SOI Dashboard | LongPaddock | Queensland Government SOI led this time last year, that the La Nina would not go strong. It seems to be having the same effect over the last few weeks.. It's also been positive 7 months in a row, including March. 2020-2023 it was positive 37 months in a row.

I saw this too.. My observation has been for the last 5+ years, we bust warmer a lot after the coldest day of the year passes (Jan 27th).. going into the early Spring

Thanks.. it's fitting the average time lag about perfectly this time (+15 days in April vs +45-60 days in Oct/Nov!) I wonder if models have a bias at all regarding SSW's and following -NAO's..

Even since Winter 18-19, we've been getting this huge -PNA/+NAO pattern.. it's actually -AAM I love this next image, because it covers a 300-month consecutive period over 25 years.. this is the 12-month total May-Apr 1999 to 2024.. When 20% of the dataset is hit like this over a consecutive period, there is a >95% chance that the max anomaly would be over the Poles.. but we have been in a La Nina base state generally since the 97-98 Super El Nino

We've been getting -NAO's in the Summer.. This is what it's been.. expansion of the Hadley Cell in the Northern Hemisphere, amped is a -PNA/+WPO pattern in the Pacific, and +NAO in the Atlantic

-NAO on models from the Stratosphere warming.. +15 days is about perfect time lag for this time of year

CPC continues doing this stuff every day since early-February.. will be interesting to see if it verifies.

This goes for everyone.. if the model is showing snow in the long range: 1) Look at the 500mb index patterns - Is the NAO negative? - Is the PNA positive? - Is the EPO negative? If not, don't expect troughs. This kind of hit me when PSUhoffman said 10% chance it verifies.. in reality, it's about 1-2%. Unless the NAO is negative, ensemble mean is showing a trough over the east, etc. For your map, I'd say it's 1% chance of verifying. It hit 82F in Portland today.

CPC has had above average precip in the area pretty much every day, in the 6-10 day and 8-14 day, since early February.. hasn't happened like that yet.

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.