GaWx

There will continue to be persistent moderate NE and then E winds during the upcoming few days followed by a freshening of them from the NE late week from a new surface high. In addition, there’s a full moon on Tue (10/7) and perigee on Wed (10/8). As a result of the moon, astronomical tides are progged to be the highest of 2025 so far Oct 7-10. Because these already quite high tides are going to combine with the current and upcoming week’s winds, as well as a stronger surge of NE winds Thu/Fri, there’s a possibility of major coastal flooding at/near high tide late this week in the corridor from CHS through GA. Those in or traveling to coastal areas late this week should keep up to date on this:From KCHS NWS:GUSTY NE WINDS RETURN THURSDAY INTO FRIDAY BEHIND THE FRONT - 25TH TO 75TH PERCENTILE REFLECTING A MOST LIKELY WIND SPEED ALONG THE COAST OF AROUND 20-30 MPH - TO END THE WORKWEEK, WHICH, IN ADDITION TO ALREADY ELEVATED TIDE LEVELS, COULD BRING A PERIOD OF VERY IMPACTFUL TIDAL FLOODING TO END THE WEEK. SEE COASTAL FLOODING SECTION FOR MORE.TIDES/COASTAL FLOODING ASTRONOMICAL TIDES WILL CONTINUE TO INCREASED THROUGH NEXT WEEK DUE TO THE UPCOMING FULL MOON (OCT 7) AND PERIGEE (OCT 8). THIS IN COMBINATION WITH THE ANTICIPATION OF CONTINUED NORTHEASTERLY FLOW WILL CAUSE THE POSSIBILITY OF COASTAL FLOODING TO BECOME MORE LIKELY ALONG THE ENTIRE COASTLINE, INCLUDING BOTH DOWNTOWN CHARLESTON AND FORT PULASKI. SALTWATER INUNDATION COULD THEN OCCUR DURING BOTH THE MORNING AND EVENING HIGH TIDE CYCLES DURING THIS TIME. ALTHOUGH THERE IS CONSIDERABLE UNCERTAINTY THIS FAR OUT, PERSISTENT FAVORABLE WINDS HAVE THE POTENTIAL TO PRODUCE UP TO MAJOR COASTAL FLOODING BY THE LATTER PART OF NEXT WEEK.

Not to minimize TS Chantal, which caused record 24 hour rainfall in some portions of C NC, but will 2025 get through the rest of this season with no Conus hurricane impact for the first season since 2015? The record longest streak with a hurricane impact is 13 seasons (1938-50). -Since 1851 there have been 34 (20%) seasons with no Conus H impact on record. Of these 34, these were only 6 during La Niña (1872, 1890, 1892, 1973, 2000, and 2010) vs a much higher 15 during El Niño, which is intuitive. The highest ACE of these 34 was 2010’s 165 (La Niña) followed by 1951’s 126 (El Nino). -Since 1851 there have been only 6 (3%) seasons with a first Conus H impact on record in Oct or later: all were in Oct and none of these 6 had a second one. None were during La Niña. The highest ACE of these 6 was 1853’s 76 followed by 2002’s 68. So, if 2025 were to join them, it would by a good margin have the highest ACE of this group and would be the first during La Niña: 1853 neutral: Oct 20th (GA) when center passing 40 miles off GA from TC 1st reported ~NW Bahamas 1923 El Nino: Oct 16th (LA) from TCG in the EPAC! 1946 neutral: Oct 7th (W FL pen.) from TCG in NW Caribbean 1968 El Niño: Oct 18th (W FL pen.) from TCG in SW Caribbean (Gladys) 1987 El Niño: Oct 12th (Keys/S FL) from TCG in SW Caribbean (Floyd) 2002 El Niño: Oct 3rd (LA) from TCG in C MDR (Lili)

I’m getting some light to moderate showers that are moving W from off the ocean. First rain of the month. The forecast is for scattered showers to continue to occur in the area through the remainder of the night and through tomorrow. There could be a few thunderstorms tomorrow afternoon.

Go to 1st post, choose edit, and then edit title.

18Z Icon has lemon as a TD near S FL and pumpkin as TS E of Leewards at 120: Edit for other 18Z: -GFS has a hurricane turn sharply 200 miles E of Leewards as it recurves -Euro is again very weak and has no TC through 144 ———Edit for 0Z 10/5 UKMET: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 102 HOURS FORECAST POSITION AT T+102 : 15.3N 57.6W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 09.10.2025 108 15.9N 59.3W 1009 33 0000UTC 10.10.2025 120 17.2N 61.9W 1007 34 1200UTC 10.10.2025 132 18.2N 64.5W 1007 34 0000UTC 11.10.2025 144 19.6N 66.7W 1005 41 1200UTC 11.10.2025 156 21.3N 68.0W 1003 44 0000UTC 12.10.2025 168 23.9N 68.4W 1000 48

How soon folks forget about Chantal, which caused record flooding in parts of NC. Also, Erin missed NC by only 200 miles and caused storm surge flooding as well as TS winds on OB. There have been many full years that had less impacts than 2025 on the E coast.

Oct 11-20 TCG W Car. climo says from a generalizing standpoint this far out that Keys/SW and S tip of FL would be at the most risk in US although each setup is unique:

Pumpkin: 12Z UKMET dropped the FL TC but still has this though it doesn’t form til 162, moving WNW to the SSW of Bermuda: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 162 HOURS FORECAST POSITION AT T+162 : 22.7N 67.7W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 11.10.2025 168 23.0N 68.5W 1009 24 ——————- 12Z Icon 933 mb at 180 but getting ready to recurve; SE US being partially protected by TS S FL from the lemon though would very likely recurve safely even without that since overall pattern shouldn't allow it to get close:

1. Humberto: the vast majority of all models never had it threaten the US 2. Imelda: -No UKMET or Icon had it hit the US and only one JMA did so. They were not only not schooled, they were the schoolers! -Several CMC had it hit as you implied. -A good # of GFS/Euro along with many ens members hit as you implied. -But some Euro AI runs hit, too, including from Humberto. So, UK, Icon, and JMA did better than Euro-AI: this top map has Humberto hit NC!

I’m in the SAV area. It’s pretty amazing how fast it has changed here. After ~17” of rain in August and water tables through the roof, I got only ~1” in Sept and see that the map you posted already has me in yellow.

For the pumpkin 0Z UK: similar to 12Z with the recurve NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 108 HOURS FORECAST POSITION AT T+108 : 15.2N 53.0W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 08.10.2025 108 15.2N 53.0W 1009 36 0000UTC 09.10.2025 120 17.2N 56.5W 1010 32 1200UTC 09.10.2025 132 19.0N 59.6W 1010 30 0000UTC 10.10.2025 144 20.1N 61.4W 1010 26 1200UTC 10.10.2025 156 21.4N 62.9W 1010 29 0000UTC 11.10.2025 168 23.2N 63.8W 1009 27

The UKMET (2nd run in a row) has the Bahamas lemon become a TC: The 0Z UKMET has itbecome a TD at 168, when it is in the NW Bahamas: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 168 HOURS FORECAST POSITION AT T+168 : 26.1N 77.8W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 11.10.2025 168 26.1N 77.8W 1007 33

Would it be possible, for continuity purposes, to incorporate it in the “two lemon” thread since most of the posts, including model output, are for the tropical ATL wave?

MJO is forecasted to continue to traverse mainly favorable phases meaning a resumption of activity fairly soon wouldn’t be surprising, especially with it being La Niña:

AAM forecast: Ninaish for at least most of month

ACE, which yesterday got to a NN 91.64, is now taking a break for awhile pending mainly what the E MDR system and any possible W Caribbean system will or won’t do next week (Bahamas AOI is very weak with only a 10% chance): note that it got to 29th out of the last 75. It just missed 2018 though it went ahead of 2024, 2016, and 2022 (2022 not shown because it was then 78.85). But, 2024 and 2016 should soon pull well ahead of 2025 during this expected 2025 respite: So, getting 100+ is still not yet certain even though it’s highly likely. I’ll give it a 95% chance since it’s La Nina and recent late seasons have been active.

12Z GEFS for pumpkin: only one of 30 hits Conus (hits S FL as a hurricane) and that’s because it is the furthest SW member (at Barbados) as it approaches the Lesser Antilles. The rest are at that time from PR to the Leewards (~50%) with ~50% at that time well NE of the Leewards: Here’s when that one member hits S FL. The one at the Outer Banks is from a NW Caribbean system: Edit: I don’t think any 12Z EPS are hitting the CONUS. If there are any, I can’t tell.

The 12Z Euro for the “pumpkin”: no TC til ~192 hours when it’s 1005 mb that’s ~125 miles N of PR. But it’s already recurving sharply then and never gets stronger than 1005 mb til it gets to 30N way out in the middle of the ocean. ———— 2PM TWO up to 0/50:2. Tropical Atlantic:A tropical wave has just emerged off the coast of Africa. The wave is forecast to interact with another disturbance over the eastern tropical Atlantic, and then move westward after that. Environmental conditions are expected to become conducive for some slow development of the system in a few days, and a tropical depression could form near or east of the Lesser Antilles by the end of next week.* Formation chance through 48 hours...low...near 0 percent.* Formation chance through 7 days...medium...50 percent.Forecaster Berg

Regarding the pumpkin: 12Z UKMET: 3rd in a row with TCG from this; similar TCG to prior run but moves NW instead of WNW and thus ends up further N than prior run although not quite as far N as two runs ago; Also this one has it become declassified at 168: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 126 HOURS FORECAST POSITION AT T+126 : 16.6N 54.6W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 09.10.2025 132 17.8N 56.3W 1009 36 1200UTC 09.10.2025 144 19.9N 59.3W 1010 30 0000UTC 10.10.2025 156 21.8N 61.2W 1009 29 1200UTC 10.10.2025 168 CEASED TRACKING

I agree 100% if someone is doing what you’re doing. But just to make sure it’s clear, JB has only 50% of his 10 winter weights within 1991+ and he has 1950-1 as a 30% weight.

Fwiw today from JB: Warm October, Warm Winter. Yes and No I received an email last night saying alot of people on X are starting to hammer our winter idea because of the warm October. And they have good reason too, because warm Octobers centered in the Northeast tend to be warm winters. Some of the worst winters I can remember are those warm, dry Octobers However there is a problem when we look at the analogs. When warm Octobers are centered in the heartland and the back part of the hurricane season ( more than 50% of ace after Sept 15) we get a very different story. What I did here with this analog is pick out the warmest Octobers since 1950 and double weighted the late season ACE ones: So what do the winters look like? Here’s my main problem with his maps. He’s using 1991-2020 for climo, which makes his winter analog composite look significantly colder than if earlier climo were used. Keep in mind that half of his years are 1989 and earlier. What’s the most appropriate climo to use from that site? There’s no easy answer but something earlier than 1991-2020 would obviously be more appropriate. Octobers are still warm no matter what climo is chosen (different degrees of warmth depending on climo that’s chosen). If I use 1951-2010, I get this: That actually shows very slightly mild or essentially NN. But perhaps that’s too far back although he does have 3 of his 10 weights as 1950-1. What about if I use 1971-2000? It’s also very slightly mild/NN in the NE US: The point is that he used too warm climo, which made his winter analog average too cold.

Regarding major impacts to crops, it’s actually been closer to the opposite with larger crops in many areas, including the US, due partially to: -longer growing seasons due to GW -ability to have decent crops further N due to GW -increased CO2 itself, due to “fertilization effect”, leads to larger crops I’ve posted about this earlier ITT. So, who’s to say that CC will ever lead to shortages of food? It may continue to be a net positive for that for all anyone knows. However, this isn’t consistent with the message about CC being all bad. Thus, it’s naturally going to be deemphasized so as to avoid a mixed message. Make no mistake that CC has its very bad impacts like sea level rise, more flash flooding events, increased frequency of intense hurricanes, increased AC costs, and increased heat related deaths. But there are some good sides, too, like larger avg crop sizes (at least so far), decreased heating costs, and decreased cold related deaths.

It would almost certainly be a miss of the Conus if it were to be a TC E of 55W per history. There hasn’t been on record even one TC existing E of 55W after October 4th that made it all of the way to the Conus! (I’ve checked all of the years.) That doesn’t mean it’s impossible and that it won’t eventually happen. But that does mean the chance is tiny. OTOH, it is were to be very slow to develop and wait, say, til near the Lesser Antilles or further W, then there would no longer be the near certainty of a Conus miss. It might then still be a likelihood but not a near certainty looking from this far out.

Chris, Who’s to say that the next 9 seasons won’t jump back somewhat given that 2016-7 through 2024-5 was the lightest 9 year avg on record? Consider this: 1948-9 through 1956-7 averaged only 10.9”, which at the time was the lightest 9 season avg on record and was much lower than the 17.6” of the prior 9 season avg: Monthly Total Snowfall for Washington Area, DC (ThreadEx) Mean 0.0 0.0 0.0 T 1.4 1.8 4.4 1.4 1.9 0.0 T T 10.9 1948-1949 0.0 0.0 0.0 0.0 T 4.4 7.4 4.0 T 0.0 0.0 0.0 15.8 1949-1950 0.0 0.0 0.0 0.0 T T 0.3 T 3.1 T 0.0 0.0 3.4 1950-1951 0.0 0.0 0.0 0.0 1.6 3.8 0.8 3.0 1.0 0.0 T 0.0 10.2 1951-1952 0.0 0.0 0.0 0.0 T 4.8 1.6 T 3.8 T 0.0 T 10.2 1952-1953 0.0 0.0 0.0 0.0 1.7 2.0 1.3 0.2 3.1 T 0.0 T 8.3 1953-1954 0.0 0.0 0.0 T 6.7 T 11.3 T T T 0.0 0.0 18.0 1954-1955 0.0 0.0 0.0 T 0.0 0.1 2.3 4.2 T 0.0 0.0 0.0 6.6 1955-1956 0.0 0.0 0.0 0.0 2.3 0.5 4.5 T 4.0 0.0 0.0 0.0 11.3 1956-1957 0.0 0.0 0.0 0.0 T 0.2 10.1 1.6 2.2 0.1 0.0 0.0 14.2 The subsequent 9 seasons jumped way up to 25.0”, one of their heaviest 9 season stretches: Monthly Total Snowfall for Washington Area, DC (ThreadEx) Mean 0.0 0.0 0.0 T 0.2 5.1 6.8 7.9 4.9 0.0 T 0.0 25.0 1957-1958 0.0 0.0 0.0 T 0.3 12.0 0.3 17.2 10.6 0.0 0.0 0.0 40.4 1958-1959 0.0 0.0 0.0 0.0 T 0.9 4.0 T T T 0.0 0.0 4.9 1959-1960 0.0 0.0 0.0 0.0 T T T 7.2 17.1 0.0 0.0 0.0 24.3 1960-1961 0.0 0.0 0.0 0.0 T 8.7 13.6 18.0 T T 0.0 0.0 40.3 1961-1962 0.0 0.0 0.0 0.0 1.3 1.2 2.0 6.5 4.0 0.0 0.0 0.0 15.0 1962-1963 0.0 0.0 0.0 0.0 T 16.2 2.1 2.0 1.1 0.0 T 0.0 21.4 1963-1964 0.0 0.0 0.0 0.0 T 6.4 8.9 11.7 6.2 0.4 0.0 0.0 33.6 1964-1965 0.0 0.0 0.0 0.0 0.2 0.5 9.1 1.9 5.4 0.0 0.0 0.0 17.1 1965-1966 0.0 0.0 0.0 0.0 0.0 0.2 21.3 6.9 T 0.0 0.0 0.0 28.4 ————— Then 1968-9 through 1976-7 attained a new 9 season record low of 10.5”: Monthly Total Snowfall for Washington Area, DC (ThreadEx) Click column heading to sort ascending, click again to sort descending. Mean 0.0 0.0 0.0 T 0.2 2.7 3.0 3.5 1.0 0.1 0.0 0.0 10.5 1968-1969 0.0 0.0 0.0 0.0 T T 0.2 2.2 6.7 0.0 0.0 0.0 9.1 1969-1970 0.0 0.0 0.0 0.0 T 6.8 3.6 3.6 T 0.0 0.0 0.0 14.0 1970-1971 0.0 0.0 0.0 0.0 T 5.2 4.8 0.3 1.4 T 0.0 0.0 11.7 1971-1972 0.0 0.0 0.0 0.0 1.4 0.1 0.3 14.4 T 0.6 0.0 0.0 16.8 1972-1973 0.0 0.0 0.0 T T 0.0 T 0.1 T T 0.0 0.0 0.1 1973-1974 0.0 0.0 0.0 0.0 0.0 11.0 1.5 4.2 T T 0.0 0.0 16.7 1974-1975 0.0 0.0 0.0 T T 0.1 6.6 5.8 0.3 T 0.0 0.0 12.8 1975-1976 0.0 0.0 0.0 0.0 0.0 0.4 0.1 0.9 0.8 0.0 0.0 0.0 2.2 1976-1977 0.0 0.0 0.0 0.0 0.8 0.6 9.7 0.0 0.0 T 0.0 0.0 11.1 That new record low had followed the prior 9 season avg of 26.5”: Monthly Total Snowfall for Washington Area, DC (ThreadEx) Click column heading to sort ascending, click again to sort descending. Mean 0.0 0.0 0.0 0.0 0.9 6.2 6.8 8.4 4.2 0.0 T 0.0 26.5 1959-1960 0.0 0.0 0.0 0.0 T T T 7.2 17.1 0.0 0.0 0.0 24.3 1960-1961 0.0 0.0 0.0 0.0 T 8.7 13.6 18.0 T T 0.0 0.0 40.3 1961-1962 0.0 0.0 0.0 0.0 1.3 1.2 2.0 6.5 4.0 0.0 0.0 0.0 15.0 1962-1963 0.0 0.0 0.0 0.0 T 16.2 2.1 2.0 1.1 0.0 T 0.0 21.4 1963-1964 0.0 0.0 0.0 0.0 T 6.4 8.9 11.7 6.2 0.4 0.0 0.0 33.6 1964-1965 0.0 0.0 0.0 0.0 0.2 0.5 9.1 1.9 5.4 0.0 0.0 0.0 17.1 1965-1966 0.0 0.0 0.0 0.0 0.0 0.2 21.3 6.9 T 0.0 0.0 0.0 28.4 1966-1967 0.0 0.0 0.0 0.0 T 16.1 1.3 19.0 0.7 0.0 0.0 0.0 37.1 1967-1968 0.0 0.0 0.0 0.0 6.9 6.3 2.8 2.4 3.0 0.0 0.0 0.0 21.4 And the new record low 9 season 1968-9 through 1976-7 avg of 10.5” was followed by an 18.8” 9 season mean for 1977-8 through 1985-6: Monthly Total Snowfall for Washington Area, DC (ThreadEx) Click column heading to sort ascending, click again to sort descending. Mean 0.0 0.0 0.0 0.0 0.4 1.1 6.7 8.7 1.8 T 0.0 0.0 18.8 1977-1978 0.0 0.0 0.0 0.0 0.1 0.2 10.3 3.8 8.3 0.0 0.0 0.0 22.7 1978-1979 0.0 0.0 0.0 0.0 3.1 T 4.0 30.6 T 0.0 0.0 0.0 37.7 1979-1980 0.0 0.0 0.0 0.3 0.0 T 8.6 5.1 6.1 0.0 0.0 0.0 20.1 1980-1981 0.0 0.0 0.0 0.0 T 0.3 4.2 T T 0.0 0.0 0.0 4.5 1981-1982 0.0 0.0 0.0 0.0 T 1.7 15.3 5.3 0.2 T 0.0 0.0 22.5 1982-1983 0.0 0.0 0.0 0.0 0.0 6.6 T 21.0 0.0 T 0.0 0.0 27.6 1983-1984 0.0 0.0 0.0 0.0 0.3 T 6.5 T 1.8 T 0.0 0.0 8.6 1984-1985 0.0 0.0 0.0 0.0 T 0.3 10.0 T T T 0.0 0.0 10.3 1985-1986 0.0 0.0 0.0 0.0 0.0 0.7 1.8 12.9 T T 0.0 0.0 15.4 ————— So, in summary: 1939-40 through 1947-8: 17.6” 1948-9 through 1956-7: 10.9” 1957-8 through 1965-6: 25.0” 1959-60 through 1967-8: 26.5” 1968-9 through 1976-7: 10.5” 1977-8 through 1985-6: 18.8” 2007-8 through 2015-6: 15.9” 2016-7 through 2024-5: 7.8” 2025-6 through 2033-4: ??? Maybe 2025-6 through 2033-4 will jump back up a nice amount. It wouldn’t at all surprise me if it were to jump back up to ~12-15”. And then perhaps it would drop back down. Obviously nobody knows. Yes, it’s overall been headed down with the warming, which is intuitive. But I assume we can agree it’s nowhere near a straight plunge.

Regarding the MDR lemon: A tropical wave is expected to move off the coast of Africa over the next day or two. Thereafter, this wave is forecast to interact with another disturbance in the eastern tropical Atlantic, and some slow development of the combined feature is possible as the system moves westward to west-northwestward at 15 to 20 mph. * Formation chance through 48 hours...low...near 0 percent. * Formation chance through 7 days...low...30 percent. Forecaster Jelsema ——————— I didn’t post it. But the 12Z UKMET had a TC form from this at 162 hours and it was already recurving/moving NW to 23.7N, 57.2W at 168. The new UKMET (0Z) forms it 18 hours earlier and it moves WNW instead of NW meaning it ends up much further S than the 12Z run had it at the end of the run (~150 miles NE of the Leewards): NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 132 HOURS FORECAST POSITION AT T+132 : 15.7N 53.2W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 08.10.2025 132 15.7N 53.2W 1009 40 0000UTC 09.10.2025 144 17.5N 56.5W 1009 39 1200UTC 09.10.2025 156 18.8N 59.3W 1009 34 0000UTC 10.10.2025 168 19.7N 61.4W 1008 31