GaWx

Followup on AEW coming off Africa as early as tomorrow: 12Z UKMET: has a TS that is already recurving before 40W: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 138 HOURS FORECAST POSITION AT T+138 : 15.3N 32.1W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 03.09.2025 144 16.0N 33.0W 1010 37 0000UTC 04.09.2025 156 16.9N 35.4W 1010 40 1200UTC 04.09.2025 168 18.6N 37.0W 1010 38

Though yesterday’s full daily average sunspot # didn’t come close to the 290 record high for the current cycle, it still was a very impressive 207 and today’s early avg is at 209: 2025 08 22 2025.640 57 8.7 25 27 2025 08 23 2025.642 75 7.0 23 28 2025 08 24 2025.645 110 8.2 31 38 2025 08 25 2025.648 139 15.2 35 42 2025 08 26 2025.651 191 21.2 30 34 2025 08 27 2025.653 207 17.2 20 28 2025 08 28 2025.656 209 15.8 10 12 @snowman19

It was negative but it was negative 1948-55. So, it was very different back then as opposed to back and forth every two years.

Though support has waned significantly since all but the GFS had it on Monday, the 0Z UKMET brought the E MDR AEW back from the dead (albeit with later TCG) with a minimal TS due to a strong pressure gradient below a rather strong Azores high moving WNW: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 156 HOURS FORECAST POSITION AT T+156 : 15.6N 33.8W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 03.09.2025 156 15.6N 33.8W 1010 34 0000UTC 04.09.2025 168 16.9N 35.9W 1011 35 ——- But GFS/Icon/CMC/Euro have no more than a weak reflection at the sfc. Yesterday’s 12Z JMA has close to a TD but it doesn’t develop further and weakens. If this were to develop, it like Erin due to latitude would be a good recurve safely candidate as of the current model consensus of steering fwiw but a long ways to go if it were to actually develop. Edit: Some EPS members develop this but only a pretty small percentage do that. The GEFS is very quiet, however.

Though support has waned significantly since all but the GFS had it on Monday, the 0Z UKMET brought the E MDR AEW back from the dead (albeit with later TCG) with a minimal TS due to a strong pressure gradient below a rather strong Azores high moving WNW: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 156 HOURS FORECAST POSITION AT T+156 : 15.6N 33.8W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 03.09.2025 156 15.6N 33.8W 1010 34 0000UTC 04.09.2025 168 16.9N 35.9W 1011 35 ——- But 0Z GFS/Icon and probably CMC have nothing.

-Indeed, only 11 of 15 La Niña seasons (I’m including 2024) since 1995 had well AN active era ACE though that’s still near 3/4 of them. -For neutral: only 1/3 had well AN active ACE -For El Niño: only 2/9 had well AN ACE -So, La Niña has been associated with the highest odds by far of a high ACE season

Models/MJO suggest it should remain pretty quiet at least through the first week of Sept. Enjoy the chilly respite/rest while we have it as it may not remain that way for too long after that.

Not that I want H hits in the SE because I don’t as I’d love a boring shutout! But keep in mind that the lowest August temp since 2001 in RDU, GSO, ATL, and most major stations in TN/NC/SC/GA and some in AL was in early to mid August of 2004. That month had a 2-3 week long stretch of BN temps. The very next month had 3 bad hurricanes hit FL.

Don’t forget that August of 2004 had 2-3 weeks straight of BN.

Keep in mind that the lowest August temp since 2001 in RDU, GSO, ATL, and most major stations in TN/NC/SC/GA and some in AL was in early to mid August of 2004. The next month had 2 bad hurricanes hit the FL E coast and 3 in total in addition to Charley in that same August.

I just researched this further. This is the source for the “monthly record low”: https://coolwx.com/record/ According to it, PDK (not ATL), which coolwx also calls “Atlanta”, did actually have an unofficial monthly record low this morning with its 55 as that broke its monthly record low of 55.4 (2004). But these PDK records go back only 44 years (1981 or 1982). To compare, KATL had a 56 on 8/14/2004. So, the KPDK 55 in August of 2004 does jibe well with the KATL official 56 then.KPDK Atlanta, GA United States 55.0 59.0 55.4 -5.8 (2013) (2004) (1985) -4.0 44 KPDK It’s not an official KATL monthly record low, which is 55 (1992 and 1986). Their low this morning was 60 vs daily record low of 57. Per this, PDK (same as Chamblee) actually got down to 54 for the low:CHAMBLEE CLEAR 57 52 83 N3 30.22R TC 14 6HR MIN TEMP: 54

Impressive spike! So, I just looked at SIDC, which shows that 290 on 7/18/24, and see “only” 204 for today’s early avg: https://www.sidc.be/SILSO/DATA/EISN/EISN_current.txt 2025 08 26 2025.651 187 21.4 26 29 2025 08 27 2025.653 204 15.3 9 13 Let’s see where the full 8/27/25 avg ends up.

Today’s Euro Weekly run not only has the most active 9/15-21 ACE yet, it is the 1st run with 9/22-8 and that is even more active than 9/15-21! It has the quietest Sep week as the 1st one and the noisiest week as the 4th one. That resembles Sep of 2024 somewhat because then the quietest weeks of ACE in Sep were the 1st (0) and 3rd (0) while the 4th had the noisiest by far with AN ACE (18.1). The 2nd had 6.1. Today’s EW ACE Sep progs vs very active 20 yr climo 1-7: 4.5 (.3) 8-14: 11.3 (.7) 15-21: 20.4 (1.3) 22-28: 22.4 (1.6) So, today’s vs climo is despite a very quiet 1st week and still BN 2nd week progging the 1st 4 weeks of Sept at 58.6, which compares to only 24.2 in 2024 and ~the active 30 year climo of ~60. To compare, look at what I posted on 8/27/24: Today’s Euro Weeklies could be nicknamed “A Tale of Two Seasons”: - Weeks 1-3 (9/2-22): remain only at ~50% of climo overall. These haven’t changed much for days other than a gradual decline. - Week 4 (9/23-29/new week “on the block”): the first forecast for that week is for 120% of climo and it follows the prior week’s modest 70%. So, it’s seeing some kind of sudden change. If it were a reversion to climo, it would be only at 100%, not 120%. Also, this is the first time there has been any week at 120%+ since the 8/16 run. Will be interesting to follow. @PhiEaglesfan712If this EW run were to verify closely, the ACE through 9/30 would be ~100 and keep the door open for a 140+ season total as 30% of Octs-Novs over the last 30 years were 40+.

Today’s Euro Weekly run not only has the most active 9/15-21 ACE yet, it is the 1st run with 9/22-8 and that is even more active than 9/15-21! It has the quietest Sep week as the 1st one and the noisiest week as the 4th one. That resembles Sep of 2024 somewhat because then the quietest weeks of ACE in Sep were the 1st (0) and 3rd (0) while the 4th had the noisiest by far with AN ACE (18.1). The 2nd had 6.1. Today’s EW ACE Sep progs vs very active 20 yr climo 1-7: 4.5 (.3) 8-14: 11.3 (.7) 15-21: 20.4 (1.3) 22-28: 22.4 (1.6) So, today’s vs climo is despite a very quiet 1st week and still BN 2nd week progging the 1st 4 weeks of Sept at 58.6, which compares to only 24.2 in 2024 and is ~the active 30 year climo of ~60. To compare, look at what I posted on 8/27/24: Today’s Euro Weeklies could be nicknamed “A Tale of Two Seasons”: - Weeks 1-3 (9/2-22): remain only at ~50% of climo overall. These haven’t changed much for days other than a gradual decline. - Week 4 (9/23-29/new week “on the block”): the first forecast for that week is for 120% of climo and it follows the prior week’s modest 70%. So, it’s seeing some kind of sudden change. If it were a reversion to climo, it would be only at 100%, not 120%. Also, this is the first time there has been any week at 120%+ since the 8/16 run. Will be interesting to follow.

The 12Z Icon, which then has it become a TS, is implying an eventual though not immediate safe recurve from the US would later occur on that run fwiw. Other 12Z runs: -GFS still doesn’t have a TC from the far E MDR AEW. However, it does now have a weak reflection at the sfc as well as upper level vorticity clearly showing up now. So, this is a hint that the GFS may in runs soon start showing this as a closed sfc low. -CMC has nothing unlike prior runs -UKMET, Euro, and JMA still yet to be released Edit: Edit: -UKMET is 2nd run in a row without it -Euro: dropped it So, for now it’s just the Icon although JMA not yet out

Sorry, I have no idea. The 12Z Icon is another run with it. It comes off Africa Fri night and is already a TD on Sat/Sat night:

Just like yesterday’s 12Z and today’s 0Z, the 6Z Euro has the low come off Africa Fri evening (not that far out…that’s why I think it’s worth posts). It becomes a TD Saturday night near the CVs, moves slightly S of due W from there, and ends up near 16N, 30W at 144 still as a TD. If this keeps up a few more runs, it would call for a lemon, especially with the CVs potentially impacted within only 5 days. Edit: Actually, with rather strong support by the Euro and Icon, some support by the CMC and JMA, and on/off support by the UKMET, I feel that if the Euro/Icon were to hold onto this at 12Z and if the UKMET were to get it back, it would then already be lemon-worthy even if the GFS still doesn’t have it.

Followup: The Euro (0Z) has this again as a weak low just off Africa. It then eventually comes across to just N of the Leewards as a H moving NW though those details aren’t important so far out on an operational. The EPS (0Z) again has a few TC members from this and they all are headed for a safe recurve from the US. The Icon (6Z) has this again at 120 just off Africa. The GFS (6Z) again doesn’t have this develop. Edit: Unlike the 12Z, the 0Z UKMET doesn’t have this as a TC. The 0Z CMC still has this as a weak low.

0Z followup to all 12Z major ops but GFS showing a surface low forming just off of Africa this weekend: 0Z Icon like 12Z has a sfc low just off Africa Sat. It becomes a TD that day and then a TS by Sun as it moves mainly W just N of the CV Islands.

I just looked at other 12Z ops and there’s actually the same general idea of a LL circ forming just off Africa within 6 days from these 12Z models: Euro, CMC, Icon, JMA, and UKMET. The GFS is about the only major op that has virtually nothing. Hmmmm. 12Z UKMET for example has a TD from right off of Africa moving WSW. When I first saw this on the UKMET, I figured it was likely going to end up as a ghost since I thought it was the only op with it. But then I saw the other models and am now wondering. 12Z UKMET: EW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 132 HOURS FORECAST POSITION AT T+132 : 17.6N 17.6W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 31.08.2025 132 17.6N 17.6W 1010 25 1200UTC 31.08.2025 144 17.3N 19.7W 1010 24 0000UTC 01.09.2025 156 17.2N 22.2W 1011 23 1200UTC 01.09.2025 168 16.7N 25.6W 1012 25

In the contest post (that you weenied lmao), I predicted 14/9/3 and 139 ACE. So, I expect another weenie here.

1. I don’t see anything near 190 ACE this season. My original prog as stated in the contest thread was for ~139. I see no reason at all to increase that. 2. MH 6? That chance is tiny. I predicted 3 MH in the contest fwiw. 3. H 8 has a much better chance than MH 6 although it will be a challenge. Fwiw, I predicted 9 H in the contest, which is on life support right now. 4. Erin’s highest winds were 160 mph, not 160 knots. I’m assuming that’s a typo.

WeatherTiger update is out: opinions? https://weathertiger.substack.com/p/real-time-2025-atlantic-hurricane?utm_source=substack&utm_medium=email&utm_content=share Cycloneye of Storm 2K said this about this update: Down to 147 today, will probably dip into the 130-135 range by 9/10 unless we unexpectedly generate some ACE before then. More importantly U.S. ACE is falling as well, odds of 3+ U.S. hurricane landfalls now less than 25%. —————- My take: Seasons with 3+ H hits on the US are considered quite active for the US. They include these over the last 30 seasons (current active era): 2024, 20, 17, 08, 05, 04, 1999, 98 So, that’s 8 out of 30 or 27% with 3+ US H hits. Thus, he’s saying odds of 3+ have dropped to slightly lower than the normal chance of the active era. That seems to me like a reasonable drop considering the chance of the first prior to Sept 7th is low per models.

Opinions? https://weathertiger.substack.com/p/real-time-2025-atlantic-hurricane?utm_source=substack&utm_medium=email&utm_content=share Per Cycloneye of Storm 2K, WeatherTiger is suggesting: Down to 147 today, will probably dip into the 130-135 range by 9/10 unless we unexpectedly generate some ACE before then. More importantly U.S. ACE is falling as well, odds of 3+ U.S. hurricane landfalls now less than 25%. —————————— Seasons with 3+ H hits on the US are considered quite active for the US. They include these over the last 30 seasons (current active era): 2024, 20, 17, 08, 05, 04, 1999, 98 So, that’s 8 out of 30 or 27% with 3+ US H hits. Thus, he’s saying odds of 3+ have dropped to slightly lower than the normal chance of the active era. That seems to me like a reasonable drop considering the chance of the first prior to Sept 7th is low per models. *Corrected

I’ll put this out here for potential discussion purposes. From met. Tony Brite: Edit: one caveat. Tony Brite is assuming 2025 will be just cold neutral ENSO. But per RONI, weak La Niña is actually favored. Also, my research suggests weak La Niña may actually be worse than cold neutral as far as the chance for a rough US hurricane season.