GaWx

After having a Medi-TC on both Sep 8th UKMET runs (TCG late 9/13 to early 9/14), the subsequent 5 runs’ textual output showed nothing. But the newest UKMET (12Z 9/11 run) brought it back albeit slightly delayed vs the two 9/8 runs with TCG ~18 hours later. This run gets it all of the way down to 986 mb. Wouldn’t it be amazing for the Mediterranean to have a TC stronger than the strongest so far in the Atlantic? NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 78 HOURS FORECAST POSITION AT T+ 78 : 34.5N 13.5E LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 15.09.2026 84 34.1N 14.1E 1010 30 1200UTC 15.09.2026 96 35.3N 16.5E 1003 43 0000UTC 16.09.2026 108 35.8N 16.7E 998 51 1200UTC 16.09.2026 120 35.4N 15.6E 993 46 0000UTC 17.09.2026 132 35.0N 17.3E 992 41 1200UTC 17.09.2026 144 35.1N 19.7E 989 51 0000UTC 18.09.2026 156 35.0N 22.5E 986 60 1200UTC 18.09.2026 168 35.2N 26.1E 991 48 @LongBeachSurfFreak

Nino 4 on latest UKMET strengthened slightly from a peak of ~+1.3 in Sep on the Aug run to a peak of ~+1.4 in Nov on the new run: Aug run: peak of ~+1.3 in Sep (non-relative) Sep run: peak of ~+1.4 in Nov (non-relative)

The UKMET, which pretty much nailed the 2023 ONI peak of ~+2.0, just updated for Sept: it peaks at ~+3.3 in Nov: The prior run (Aug) had peaked at only +3.1: Regarding Nino 1+2, it also strengthened: New run: a little >+4 (this like for 3.4 above is not relative and thus doesn’t taken into account GW well): Prior run (Aug): ~+3.8

Mean of last 3 days worth of CFSv2 runs has this for Sep 25-Oct 1st:

The latest Euro Weeklies suggest to watch the Gulf during Sep 28-Oct 4th:

Latest 10 day CFSv2 ens mean for RONI shows the downward trend continuing: note for SON through NDJ how much lower are the blue lines (the most recent 8 members) vs the red lines (the earliest 8 members):

The just released WCS daily PDO for yesterday was up to -0.58! They haven’t been this high since way back in late June. It has risen ~1.07 over just the last 10 days. It had dipped to as low as -2.19 on Aug 1st. In case anyone is wondering, it hasn’t been red since it went barely positive on ~6 dates between 3/31/25 and 4/19/25 (highest was ~+0.08 on 4/5/25). One can also see it barely missed going red on 3/1/26. But unlike then and Mar-Apr of ‘25, there’s obviously now a supportive for a higher PDO full fledged very strong Nino:

I got ~0.6” 9-10AM from a nice batch of convection moving NNE over almost the entire SAV area.

I’d love this combination for the SE US!

Also, -3/24/1983 Miller A Gulf coast major snowstorm that crossed over N FL and then offshore the SE -2/8-10/1973: historic Miller A deep Gulf snow storm that crossed C FL to well off SE coast

Thanks for that info. It seems that this has been a really bad year for Hawaii! When was the last season as bad as this? And the season is far from over! -H Lala: extreme rainfall and very strong winds to H force in some cases -TS Moke: additional heavy rains along with gusty winds only a week after Lala thus hampering recovery efforts -H Lowell: lots of damage from sustained TS force/gusts to H force W islands, significant storm surge, and very high waves

I’ve been following this closely. CFSv2 has dropped RONI peak from +3.5 to +3.0 over last month or so due to August pause. That’s just a pause though and notable 3.4 warming has finally resumed. But I don’t see it catching back up. Thus, I’m currently at +3.0 for my educated guess. The BoM is way up at +3.6 and will likely bust too high like it did in ‘23. However, its SST anomalies are based on a dataset that’s ~0.3 to 0.4 warmer than ERSST, which NOAA uses, and which just adds confusion. Keep in mind that 1+2 has recently been strong thus making it the most E based on record for early Sept. beating 1997.

In my two Maroon Bells posts above where I mentioned elevations, I meant I was hiking at 9.5-9.7K ft, not 11.5-11.7K feet lmao. Sorry for the typo! I came back to warm/humid GA last week. I hope to return next summer! The change hit me like a ton of wet hot bricks! @mayjawintastawm@Chinook@ValpoVike

July ‘26 ERSSTv6 relative 3.4 was +1.333 per this: https://www.cpc.ncep.noaa.gov/data/indices/Rnino34.ascii.txt Do you have a link to the monthly GAMSSA data? Using the image below, the July ‘26 relative 3.4 BoM is ~+1.7 meaning a difference of ~0.37 between it and ERSSTv6:

Thanks, Mitch. That means the WCS PDO has risen ~0.92 over just the last 9 reporting days, and that’s the highest daily WCS PDO since way back on June 30th: