GaWx

But isn’t a KU a pretty random event that can happen in just about any winter if things happen to line up? In other words, isn’t there at least some KU potential every winter (I realize the probabilities vary each winter) because it’s random?

12Z summary of main ops-Icon H 250 miles E/SE of Bermuda 9/22-3-GFS another relatively weak run with a TS over Bermuda but takes 10 days (9/27)!-CMC H 150 miles E/SE of Bermuda 9/22-Euro H 200 miles E/SE of Bermuda 9/22-JMA out to only 72 as a TD recurving-UKMET: TS ~150 miles E of Bermuda 9/22:NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 24 HOURSFORECAST POSITION AT T+ 24 : 20.0N 50.9WLEAD CENTRAL MAXIMUM WINDVERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)-------------- ---- -------- ------------- -------------1200UTC 18.09.2025 24 20.0N 50.9W 1009 350000UTC 19.09.2025 36 20.8N 53.2W 1009 311200UTC 19.09.2025 48 21.3N 55.3W 1010 290000UTC 20.09.2025 60 22.4N 58.1W 1011 301200UTC 20.09.2025 72 23.6N 59.5W 1011 270000UTC 21.09.2025 84 25.1N 61.1W 1011 291200UTC 21.09.2025 96 26.9N 61.2W 1011 330000UTC 22.09.2025 108 29.3N 62.0W 1008 431200UTC 22.09.2025 120 31.2N 62.2W 1007 470000UTC 23.09.2025 132 33.5N 61.9W 1005 411200UTC 23.09.2025 144 36.5N 58.5W 1003 420000UTC 24.09.2025 156 39.5N 52.7W 994 431200UTC 24.09.2025 168 42.3N 44.3W 982 52

Followup: JB was surprisingly quiet. All he said was this: “Now, the red-hatched area has been designated Tropical Depression 7, posing a threat to Bermuda but not the U.S.” But then he immediately mentioned a possible unexpected “side-show Bob” to form off the SE US.

I love the “battle-zone” that so many forecasters love to put much of the SE US in every winter lol.

Thanks. Indeed, the chances of exceeding 100 total continue to decline. For reference, the 1991-2020 average from now to the end is 51: -22 rest of Sept -22 during Oct -6 during Nov -1 during Dec So, to reach 100, 2025 would need to be ~10 above the 1991-2020 avg, a tall but not near impossible order. But it being a weak La Nina and recent seasons being pretty heavily backloaded help those chances to an extent. What Gabrielle does or doesn’t do will be a pretty significant part of the mix.

I bet Bastardi will have a thing or two to say about this upgrade lol.

Check this out folks: 0Z GFS is much weaker with strongest at 1005 mb/barely a TS followed by it weakening and then dissipating over open water of the SW Atlantic into nothing! The prior 13 runs all had hurricanes, usually MH! What the? ————— 0Z UKMET: passes just E of Bermuda (similar to 0Z Euro): TROPICAL DEPRESSION 92L ANALYSED POSITION : 14.4N 43.9W ATCF IDENTIFIER : AL922025 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 17.09.2025 0 14.4N 43.9W 1010 28 1200UTC 17.09.2025 12 16.9N 45.4W 1009 33 0000UTC 18.09.2025 24 19.5N 48.0W 1009 41 1200UTC 18.09.2025 36 20.7N 50.6W 1008 37 0000UTC 19.09.2025 48 21.3N 53.3W 1008 31 1200UTC 19.09.2025 60 21.7N 55.6W 1009 27 0000UTC 20.09.2025 72 22.0N 57.6W 1010 26 1200UTC 20.09.2025 84 23.3N 59.0W 1010 30 0000UTC 21.09.2025 96 24.8N 60.2W 1010 29 1200UTC 21.09.2025 108 26.2N 60.8W 1010 32 0000UTC 22.09.2025 120 27.5N 61.9W 1009 37 1200UTC 22.09.2025 132 29.2N 63.5W 1010 37 0000UTC 23.09.2025 144 31.1N 63.5W 1010 34 1200UTC 23.09.2025 156 33.1N 62.8W 1010 33 0000UTC 24.09.2025 168 34.0N 59.7W 1009 30

AAM says solid La Niña like for next month: @snowman19

There's no indication it’s tropical. But it’s a hybrid of sorts though hybrid doesn’t necessarily mean subtropical, which is a type of hybrid, either. Most pro mets I’ve seen are saying not ST. I had been wondering if it could be ST.

What the? @donsutherland1@snowman19@bluewave

8 PM TWO: Central Tropical Atlantic (AL92): Showers and thunderstorms associated with an elongated area of low pressure located about midway between the Windward Islands and the Cabo Verde Islands have changed little in organization during the past 12 hours or so. However, environmental conditions are conducive for additional development, and a tropical depression or storm is expected to form in the next day or two as the system moves west-northwestward or northwestward at 10 to 15 mph over the central tropical Atlantic. Additional information on this system, including gale warnings, can be found in High Seas Forecasts issued by the National Weather Service. * Formation chance through 48 hours...high...90 percent. * Formation chance through 7 days...high...90 percent.

Here’s another one, Don: Mysterious ‘warm blob’ re-emerges in Pacific Ocean, long-term impacts expected by: Mike Masco Posted: Sep 15, 2025 According to the National Oceanic and Atmospheric Administration, the North Pacific sea surface temperature hit 20°C (68°F) in August, which would put it as the highest on record. For perspective, the first time it reached 19°C was 11 years ago, with records dating back to 1854. This event marks the fourth-largest marine heat wave since 1982, spanning a vast region from north of Hawaii to the coasts of California and Alaska. From a meteorological view, this setup can be significant. The warm anomaly tends to build high-pressure ridges over the Pacific Northwest, which pushes the jet stream eastward, often unleashing colder Arctic air into the eastern U.S.. This developing pattern closely mirrors what happened in the summer, fall and winter of 2013–2014, which featured: A neutral-to-weak La Niña ENSO pattern Below-average hurricane activity in the Atlantic Massive cold outbreaks and snowfall across the Northeast That year, New York City recorded 57 inches of snow, Philadelphia saw 63 inches, and the following year, Boston shattered records with 110 inches. Is history repeating itself? The current oceanic and atmospheric setup strongly resembles the winter of 2013–2014, raising the possibility of another brutal season for the East Coast — especially with hurricane activity already trending below normal, just like it did back then. https://wgntv.com/news/mysterious-warm-blob-re-emerges-in-pacific-ocean-long-term-impacts-expected/

Regarding this nor’easter, here’s chaser Josh-iCyclone’s take:

For the E MDR lemon from the 2PM TWO: 2. Eastern Tropical Atlantic: A tropical wave just offshore of the west coast of Africa is producing an area of disorganized showers and thunderstorms. Some slow development of this system is possible towards the latter part of this week as it moves westward at 15 to 20 mph, moving from the eastern to central portion of the tropical Atlantic. * Formation chance through 48 hours...low...near 0 percent. * Formation chance through 7 days...low...20 percent.

More 12Z runs: The models have switched in some cases. The GFS/CMC moved W to just SE of Bermuda whereas the Euro moved E to well E of Bermuda. Icon: still well to the SW of others with it much weaker SSW of Bermuda then recurving NWJMA: TS at Bermuda at 192

Great Q, big ten fan! 1. The UK has been found to be a top tier model when looking at average errors over the longterm. 2. I like to post all of the majors, good model or not. But I like to post the UK also for some other reasons like: -it’s the only one I can find with definitive textual output that’s easy to post without taking up image space and it allows one to post the entire run for a TC on just one page -so, it’s also good for documentation purposes for when one wants to look back at it for a particular TC or a TC that never formed like the recent Invest 91L -this complete run’s textual output comes out earlier than all but the Icon of the majors -The UKMET is often overlooked. You see lots of Icon, GFS, and Euro posts, but hardly any UK despite it overall being a good model. So, I happily fill in that gap.

12Z UKMET: center passes just SE of Bermuda NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 36 HOURS FORECAST POSITION AT T+ 36 : 19.4N 49.2W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 18.09.2025 36 19.4N 49.2W 1008 42 1200UTC 18.09.2025 48 20.2N 51.3W 1007 37 0000UTC 19.09.2025 60 21.1N 53.9W 1007 33 1200UTC 19.09.2025 72 21.6N 56.5W 1008 28 0000UTC 20.09.2025 84 22.8N 58.1W 1008 31 1200UTC 20.09.2025 96 24.1N 59.6W 1009 30 0000UTC 21.09.2025 108 25.8N 59.8W 1008 37 1200UTC 21.09.2025 120 27.3N 61.2W 1005 46 0000UTC 22.09.2025 132 28.8N 62.3W 1003 44 1200UTC 22.09.2025 144 30.3N 63.0W 1001 44 0000UTC 23.09.2025 156 31.7N 63.0W 1000 49 1200UTC 23.09.2025 168 32.5N 61.5W 998 43

Good discussions all! Unlike like the last couple of runs, the 12Z UKMET has no followup TC to 92L.

Maybe we need a RAMO (relative AMO) in addition to classic AMO sort of like we now have RONI in addition to the classic ONI.

Do you think that this possibly could have properly been classified as a subtropical storm? Is this mainly a baroclinic low but with some tropical characteristics?

2. Eastern Tropical Atlantic: A tropical wave emerging off the west coast of Africa is producing an area of disorganized showers and thunderstorms. Some slow development of this system is possible towards the mid to latter part of this week as it moves westward at 15 to 20 mph, moving from the eastern to central portion of the tropical Atlantic. * Formation chance through 48 hours...low...near 0 percent. * Formation chance through 7 days...low...20 percent.

But what do you think about the possibility that this also has some tropical characteristics making it subtropical?

True. In this case though, keep in mind that this wasn’t even given a 10% chance in any TWO to become just a subtropical depression. The TWOs cover both tropical and subtropical depression+ development potential.

Keep in mind that this wasn’t even given a 10% chance in any TWO to become just a subtropical depression. The TWOs cover both tropical and subtropical depression+ development potential.

I’m not sure as it’s somewhat subjective. I’m thinking more about subtropical than tropical. But the NHC never even had it at a 10% chance to transition to subtropical or tropical in any TWO, which is what really made JB mad initially.