GaWx

I got just a T after sunrise yesterday. My total for Sept was a mere 1.04” vs 17.1” in August.

The ICON and UKMET were absolutely stellar in that neither model had even one run hitting the coast or even stalling at the coast. None ever got closer than 100 miles from the US. I made sure to post every UKMET with a TC as well as any Icon that nobody else posted. All of the UKMET runs 12Z of 9/23 through 0Z 9/28 run (except 0Z of 9/24, which had no TC) in textual form can be seen ITT. The Icons going back to 12Z on 9/24 are still on Tropical Tidbits: https://www.tropicaltidbits.com/analysis/models/ ICON: The only Icon that I don’t know with 100% certainty is the 18Z of 9/24 because it goes out only 120 and is then moving very slowly NW toward C FL at ~79.0W (see 1st quoted post above). But even it is slowing down 100 miles offshore FL, the closest of any ICON to the US, and quite possibly about to make the hook OTS. UKMET: The other 4 quotes are of the furthest west UK runs. The two 9/25 runs move to 78.3W. Then the 9/26 12Z and 9/27 0Z move to 78.5W, the furthest W runs. All others’ furthest W were 77.1-77.4W. The closest to the US of any UKMET run was 115 miles E of Ft. Lauderdale (0Z 9/25 run). Furthest W of each UKMET run: 9/23 12Z: 77.1W 9/24 0Z: no TC 9/24 12Z: 77.2W 9/25 0Z/12Z: 78.3W 9/26 0Z: 77.3W 9/26 12Z and 9/27 0Z: 78.5W 9/27 12Z: 77.3W 9/28 0Z: 77.4W Whereas the UK’s record on the tracks was the best of all models (even better than the Icon), it was the latest on first having it as an actual TC (12Z 9/23) and also it didn’t have it on the 0Z 9/24. So, it was too genesis shy very early on, which is not uncommon with it. That’s why I pay extra attention when the UKMET first has a TC. Aside: The UKMET (#1) and ICON (#2) were also by far the best with Ian (‘22). ———— Honorable mention for JMA, which had only one run hit the US (NC). But like the UKMET, it was a bit shy early on in showing a TC. Despite its pretty poor record on the track along with Euro and CMC, an honorable mention is due for the GFS for showing Imelda as far back as one 9/19 run, way earlier than any other model, even though it lost it for a couple of days after that run. * Imelda’s actual furthest W was 77.3W. @WxWatcher007

Check this out. It turns out that Humberto and Imelda are the two closest Atlantic hurricanes on record (at 467 miles) other than a highly unreliable two unnamed hurricanes in 1853 (428 miles apart). Next closest of reliable years was Easy and Fox in 1951 (497 miles)!

I don’t have the answer though it may not. But regardless, I just find it absolutely fascinating that it has and will continue to be dominated by the “wrong” way for 6 weeks. I can’t find any longer than about 1/2 month like this over the last 50 years in Jul-Dec. (I haven’t checked Jan-June.) What I’ve love to know is what unique set of factors is allowing this to happen?

The unptecedented for the 2nd half of the year (since MJO records started in 1974) very lengthy clockwise dominated track continues with still no end yet in sight. It started Sept 1st and is projected to continue at least through Oct 12th, which would mean 6 weeks long! GEFS: clockwise at least through Oct 14th EPS: clockwise at least through Oct 12th @snowman19Has Roundy said anything about this?

Favorable ACE looks to continue through the foreseeable future: (note that favorable phase 2 just produced Humberto and Imelda) GEFS: going backwards through 2/1/8 EPS: going backwards through 2/1/8

Based on RONI, 2024-5 was a moderate La Niña: ASO 2024 -0.75 SON 2024 -0.81 OND 2024 -0.92 NDJ 2024 -1.07 DJF 2025 -1.12 JFM 2025 -0.89 FMA 2025 -0.67 Related to this, the Australian BoM has switched from ONI to RONI for its official model forecasts: says we’re already in a weak La Niña though it will weaken starting in Nov:

And this general idea of a big ACE comeback has been forecasted for several weeks by the Euro Weeklies. The EW after an upcoming break once Humberto and Imelda dissipate continue to forecast ACE to pick up again as we get to mid and even moreso as we approach late month.

BULLETIN Hurricane Imelda Intermediate Advisory Number 15A NWS National Hurricane Center Miami FL AL092025 800 AM EDT Tue Sep 30 2025 ...IMELDA BECOMES A HURRICANE... SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION ---------------------------------------------- LOCATION...29.0N 76.9W ABOUT 180 MI...290 KM N OF GREAT ABACO ISLAND ABOUT 755 MI...1215 KM WSW OF BERMUDA MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H PRESENT MOVEMENT...NE OR 35 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...980 MB...28.94 INCHES @WxWatcher007

JB has been pushing the idea of warm Oct/cold Dec. @snowman19i know you’re shocked lol.

I got ~0.05” last night. That gets me to 0.95” for MTD. There is a small band moving SW from S SC that may give me a little more soon. *Edit 9/30 9:05AM: That band yesterday afternoon gave me ~0.09”. Gives me 1.04” MTD. A few showers are in the area this morning (9/30), but amounts should be very light.

The SE US dodged a potentially very deadly bullet. Whew!

The Gulf looks somewhat active (more active than most of the season so far) overall on the 12Z models so far through 192 (Icon, GFS, CMC). However, the UKMET, which goes out only 168, did drop the Gulf TC per its textual output that it had on its prior 2 runs.

The 2025 ACE is now up to ~80, or near the 1951-2024 avg with it rising rapidly. I project it to reach ~88 as of the end of Sept, which compares to 94 for 1991-2020 and ~81.5 for 1951-2024. So, essentially 2025 will go in the books as NN through Sept. Humberto and Imelda should get 2025 to ~95 in early Oct. (near normal for then per 1991-2020). As of 9/30, 2025 will exceed 2024 and 2022 by 9-10 and be only ~2 under 2018. The 88 would move 2025 ahead of 1971 and 1981, which would then move 2025 up to 30th highest of the last 75 years. This chart’s avg. is based on 1951-2024, which is lower than 1991-2020. That’s why 2025 already hit the average line:

I‘m not sure exactly what you’re asking. But I do know that both the Icon and the UKMET on every single run going back to when they first had this on their runs 5+ days ago had this after moving it N to NNW hook sharply right OTS. They were absolutely stellar and were far better than any other non-JMA models with their essentially perfect records. I have the JMA as a clear 3rd as only its 12Z 9/23 run hit NC. All others hooked sharply right and OTS although two of them (12Z 9/25 and 12Z 9/26) combined with Humberto to make one storm. All of this is still on Tropical Tidbits for those who are interested. They have runs back a full week. Check them out before it’s too late! Edit: The 18Z 9/24 Icon, which goes out only 120 hours, didn’t go out far enough to be able to tell for sure. It had Imelda further N than most other runs and she was getting pretty close to FL when the run ended. But she was moving very slowly and could have easily hooked right had the run gone out further as that’s about the time the right hook would have started.

BULLETIN Tropical Storm Imelda Intermediate Advisory Number 11A NWS National Hurricane Center Miami FL AL092025 800 AM EDT Mon Sep 29 2025 ...IMELDA CONTINUES NORTHWARD AND A LITTLE STRONGER... ...TROPICAL STORM CONDITIONS CONTINUE OVER THE NORTHWEST BAHAMAS THIS MORNING... SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION ---------------------------------------------- LOCATION...26.3N 77.0W ABOUT 10 MI...15 KM SE OF GREAT ABACO ISLAND ABOUT 265 MI...425 KM ESE OF CAPE CANAVERAL FLORIDA MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...N OR 360 DEGREES AT 9 MPH...15 KM/H MINIMUM CENTRAL PRESSURE...993 MB...29.33 INCHES

BULLETIN Hurricane Humberto Intermediate Advisory Number 19A NWS National Hurricane Center Miami FL AL082025 800 AM AST Mon Sep 29 2025 ...HUMBERTO A LITTLE STRONGER AND EXPECTED TO PRODUCE DANGEROUS SURF FOR BERMUDA AND MOST OF THE U.S. EAST COAST THIS WEEK... ...TROPICAL STORM CONDITIONS POSSIBLE IN BERMUDA ON TUESDAY... SUMMARY OF 800 AM AST...1200 UTC...INFORMATION ---------------------------------------------- LOCATION...27.5N 67.3W ABOUT 365 MI...585 KM SSW OF BERMUDA MAXIMUM SUSTAINED WINDS...145 MPH...230 KM/H PRESENT MOVEMENT...NW OR 320 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...938 MB...27.70 INCHES

A notable number of 6Z EPS members at 144 (~1/3) have a surface low in the Gulf (mainly northern portion) from something:

The 30 year average (1991-2020) ACE as of Sept 30th is 94. 2025 as you implied is projected to be close to that making it near the average for the end of Sept. Looking ahead: the Euro Weeklies, weak La Niña, and recent active late seasons tell me that ending the season at least near the 30 year average of 122 is likely. Even my pre-season prog of 139 is in reach.

The 0Z UKMET (a model that tends to be a bit more stingy with TCG than the GFS) is the 2nd run in a row that develops a TC from the current C Gulf weak surface low after it moves S into the Bay of Campeche. This run actually has minimal TS winds early on. Whereas the prior run then moved it into a threatening position in the W-C Gulf, this run only moves it slowly back N to the end of the run: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 108 HOURS FORECAST POSITION AT T+108 : 19.9N 94.7W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 03.10.2025 108 19.9N 94.7W 1009 36 0000UTC 04.10.2025 120 19.7N 93.9W 1008 31 1200UTC 04.10.2025 132 19.5N 93.9W 1006 31 0000UTC 05.10.2025 144 20.1N 94.2W 1005 29 1200UTC 05.10.2025 156 20.2N 94.0W 1005 26 0000UTC 06.10.2025 168 20.7N 94.5W 1004 27

BULLETIN Tropical Storm Imelda Intermediate Advisory Number 8A NWS National Hurricane Center Miami FL AL092025 200 PM EDT Sun Sep 28 2025 ...DEPRESSION BECOMES TROPICAL STORM IMELDA... ...TROPICAL STORM CONDITIONS EXPECTED OVER THE CENTRAL AND NORTHWESTERN BAHAMAS THIS AFTERNOON AND EVENING... SUMMARY OF 200 PM EDT...1800 UTC...INFORMATION ---------------------------------------------- LOCATION...23.9N 77.3W ABOUT 95 MI...155 KM WNW OF THE CENTRAL BAHAMAS ABOUT 370 MI...600 KM SE OF CAPE CANAVERAL FLORIDA MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...N OR 355 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...998 MB...29.47 INCHES @WxWatcher007

I wasn’t paying any attention to the Gulf at all due to Humberto and TD9 til just now. I just noticed on the most recent runs that just about all models have a weak but notable surface low/spin initialized in the C Gulf that then drifts SW to the Bay of Campeche, where it seems to stall just W of the Yucatan at ~hour 96. Interesting. And lo and behold, there’s a TD on the UKMET (12Z) for the first time in the Bay of Campeche at hour 120 that then drifts N through the end of the run to a threatening position in the W central Gulf. I just saw new UK maps and this UK TD is from the same low that’s now in the C Gulf! NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 120 HOURS FORECAST POSITION AT T+120 : 20.7N 93.3W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 03.10.2025 120 20.7N 93.3W 1009 26 0000UTC 04.10.2025 132 21.1N 93.0W 1007 25 1200UTC 04.10.2025 144 22.3N 93.0W 1005 30 0000UTC 05.10.2025 156 22.8N 92.8W 1004 24 1200UTC 05.10.2025 168 24.4N 92.8W 1005 26 ——————— 12Z UKMET at 168 hours: this TD originates from the current C Gulf low and this becomes a TD on this run at 120, which moves N to this position at the end of the run (168): Also, check out the 12Z GFS at 168: there’s a TD that forms off of LA that then moves N into that state. That may or may not be directly related to the current C Gulf low, however, based on looking at vorticity maps.

Per the latest Euro Weeklies: After Humberto and Imelda wind down ~10/4-5, there looks to be a brief break overall. However, don’t get too comfortable as activity markedly picks up again to above normal on the run in the Gulf, NW Caribbean, and SW Atlantic (including Yucatan, Cuba, NC/NE US Gulf coast, FL/SE US coast, Bahamas, and Bermuda) with 140% of normal 10/13-19 and 160% of normal 10/20-26. This would be a 3rd peak of sorts for 2025 should it verify. This active period would resemble a somewhat toned down version of the freakishly active late seasons of 2020 and 2005 and similar to 1950, 1878, and 1870 for that area. 10/13-19: 10/20-26:

All major 6Z models including hurricane models stay away from the US. As of the 5AM advisory, it finally started moving a little faster and that’s continuing now on the 8AM with SLP dropping to 1002 mb: BULLETIN Tropical Depression Nine Intermediate Advisory Number 7A NWS National Hurricane Center Miami FL AL092025 800 AM EDT Sun Sep 28 2025 ...DEPRESSION MOVING SLOWLY NORTH-NORTHWESTWARD... ...HEAVY RAINS CONTINUE OVER PORTIONS OF EASTERN CUBA AND THE BAHAMAS, WITH WINDS SOON INCREASING OVER THE BAHAMAS... SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION ---------------------------------------------- LOCATION...23.2N 77.3W ABOUT 285 MI...460 KM NW OF THE EASTERN TIP OF CUBA ABOUT 100 MI...160 KM WSW OF THE CENTRAL BAHAMAS MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...NNW OR 345 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES

Unlike prior two runs, the 0Z Euro stays away from US. Also, unlike some hurricane model runs yesterday that curved back into SC/GA, the 0Z runs all stayed offshore that area.