Stormchaserchuck1

Daily records 4 days with an average of beating previous record by +10F/day.

New NWS forecast has downtown Phoenix hitting 108F Friday, with 11 days to go in the month. This is up there in std's of top records broken. June 2021 in the PNW and SW Canada comes to mind.

NWS forecast for Phoenix.. their all time March high on record was March 26, 1988, 100F. They have only hit 100 once in March (someone correct me if I'm wrong, that's what I've seen other people post). Wednesday Sunny, with a high near 102. Thursday Sunny, with a high near 105. Friday Sunny, with a high near 107. Saturday Sunny, with a high near 106. Sunday Mostly sunny, with a high near 103.

It will be interesting to see if RONI vs ONI makes a difference this season, because RONI will be ~-0.5c vs ONI. That difference in Moderate Nino range is historically about 2 NS/yr 2023 was +1.1c RONI (ASO), and +1.6c ONI and that season had 20 Named Storms, and slightly above average ACE. (SSTAs in the Atlantic so far this year are nothing close to 2023).

^Well we've had 5/6 recent years La Nina (RONI), and 7/10 recent years La Nina. In 20-21 we were -0.1c away from Strong Nina, so I don't think we are "due". Actually history shows that 4/6+ ENSO-state occurrence flips in the following 3-5 years 2:1

And temps higher than the low 60s

I think getting off for a thunderstorm is a little ridiculous, temps will be what low 60s? But kids probably go to school too much anyways.

2009 -1.3 1986 -0.3 If you're going to include those, you should include 1957: -2.7 So we've never in developing Moderate+ El Nino's since 1950 had a March SOI over +2.1 Now it has recently reversed on the daily from positive, to negative (-9) on March 15th.

Sometimes. Here is how a Nino 3.4 El Nino usually develops.. first over the dateline: Sometimes Stronger El Nino's will develop in the far east and spread west to Nino 3, but they typically don't jump to where the western ENSO regions have the same +std as the east.

12z ECMWF has Phoenix hitting 104-104 March 20-21. 12z EPS is 103-102

An El Nino is likely to develop by the Summer of 2026. The ENSO subsurface is very warm Since 1985, the most extreme ENSO subsurface anomalies for this time of the year, 8/10 (80%) became favored warm/cold ENSO state later that year. The CPC on March 12 has put up an El Nino watch for 2026: Climate Prediction Center: ENSO Diagnostic Discussion They are giving an 80% chance that August-Sept-Oct (peak Hurricane season) will be El Nino In 1995, a positive phase to the AMO cycle began, and a major uptick in Atlantic Hurricane activity occurred. Since 1995, we have averaged the following number of storms per year in various ENSO states (using the RONI): El Nino (7 years): 12.1 TS, 5.0 Hurr, 2.6 MH Neutral (11 years): 16.1 TS, 8.0 Hurr, 3.4 MH La Nina (13 years): 17.4 TS, 8.4 Hurr, 4.3 MH Climate Prediction Center - Relative Oceanic Niño Index (RONI) El Nino has been associated with much lower activity, and that occurs back to 1950 and before. Since 1995, Strongest 3 El Nino's (ASO>+1.2): (3 years): 10.3 TS, 3.7 Hurr, 1.7 MH Since 1995, Weakest 4 El Nino's (ASO<+1.1): (4 years): 13.5 TS, 6.0 Hurr, 3.3 MH So, there has been a pretty big difference between the El Nino being weaker or stronger for the Hurricane season in terms of total activity. It's important to monitor ENSO going forward, current projections are probably right around +1.0 ASO RONI. AMO CPC AMO Index stopped updating January 2023 I made a raw and smoothed graph of the AMO 1995 to Jan 2023: Raw Smoothed In Summer/Fall 2023, the Atlantic was record warm, and then Summer/Fall 2024 was warmer than that. They were the #2 and #1 AMO Seasons on record, so the trend continues to be Up-general, although the 2025 Season was much colder Atlantic SSTs. Record warm SSTs in 2023 helped 20 Named Storms occur (4th highest all time) in a +1.1c ASO El Nino. Last season (2025) was a colder AMO in Weak La Nina, and had 13 Named Storms, 4 Major Hurricanes. Anomalies in a bunch Something that we have seen in the past few seasons is Top 1% Rapid Intensification with certain storms. 2023 - Lee 2024 - Milton (honorable mention to Beryl, the earliest Cat 5 on record) 2025 - Erin and Mellisa What are some other indicators to how active the season will be? April-May Atlantic Sea-level pressure Since 1995, the most active Atlantic Hurricane Seasons minus the least active Atlantic Hurricane Seasons, have this preceding April-May sea-level pressure anomaly in the Northern Hemisphere -AO and -NAO in April-May precedes more active Atlantic Hurricane seasons +AO and +NAO in April-May precedes less active Atlantic Hurricane seasons Atlantic SSTs Current global SSTA [time sensitive] Never too early to start discussing! Thoughts? Related Discussions:

Ok, I saw a different graph at another time.

Salt Lake City, UT has 0.1" snow for the year. #2 lowest for them on record is in the 20's. That's going to hold through at least the 3rd week of March.

CPC increased El Nino chances by 15% Climate Prediction Center: ENSO Diagnostic Discussion

What a ridge in the West and Midwest!

SOI remains very positive for a developing Stronger El Nino 13 Mar 2026 1013.78 1004.20 26.18 15.03 10.39 12 Mar 2026 1012.94 1003.80 24.08 14.12 10.15 11 Mar 2026 1012.23 1003.95 19.96 13.50 9.83 10 Mar 2026 1012.41 1004.15 19.86 12.99 9.54 9 Mar 2026 1013.31 1004.00 24.89 12.33 9.38 8 Mar 2026 1013.00 1003.05 27.95 11.43 9.31 7 Mar 2026 1012.90 1002.50 30.11 10.84 9.13 6 Mar 2026 1012.74 1003.30 25.51 10.77 8.71 5 Mar 2026 1010.85 1003.90 13.59 10.96 8.17 4 Mar 2026 1011.34 1003.15 19.53 11.31 7.65 3 Mar 2026 1010.85 1002.70 19.34 11.46 6.95 2 Mar 2026 1010.44 1002.95 16.18 11.70 6.42 1 Mar 2026 1011.79 1003.40 20.49 11.80 6.11 28 Feb 2026 1011.80 1003.50 17.10 11.49 5.74 Lots of month to go, but March is currently on pace to be the Most +SOI month since before the 23-24 Strong Nino. Later-in-the-year Strong Nino March's: 2023: -1.78 2015: -10.7 1997: -7 1991: -10.1 1982: +0.7 1972: +1.2 1965: +2.1 ^since 1950

Not really a good N. Hemisphere 500mb pattern until the NAO goes negative the last week of March ENSEMBLE LOOP The SW, US ridge as a dominant factor is the best going for us, as a we drop a trough over and east of it, the pattern of the Winter.

Early March Stratosphere warming is starting to connect with -NAO on long range models towards the end of March.

They usually develop further east in Nino 3 and Nino 1+2, because on average there is cooler water there. If the whole area is neutralizing (average state is trade winds and colder SSTs along the equator), then the biggest difference is further east.

12z GFS ensembles now have -NAO from SSW +lag time The last few SSW's didn't have anything in the 3-4 week models (had +0.3-0.4 NAO), then trended for -NAO within the 2 week in the allotted lag time.

This is the following Winter - so you can see the PHX happening is a developing-El Nino occurrence as this Winter precip pattern is very El Nino There has never been a year in the 70-year composite that matched the "Winter before El Nino" better, in the CONUS

Hottest March's in Phoenix, rolled forward to the following April - August (29 analogs) 12z EPS mean for Phoenix has 100, 102, 101 March 19-21. Their all time monthly high for March was 100 on March 26, 1988.

A little trend toward -NAO after the early March SSW. The last few SSW's have been missed by models in the 3-4 week, then they catch on at about 10-day.

^After March, can you do the Dec-March temperature rankings for Phoenix? My guess is it will be 3-4F above #2. Todays 12z EPS has 100, 102, 101 in PHX.

Some pictures from the snow