GaWx

The 0Z GFS has joined the hybrid/nor’easter party for a week from today: Edit: GEFS largely agrees with the GFS big change

Not always though. See 2023-4, for example, which was way too cold along with most other models. They all forecasted a classic Nino Aleutian low and you probably remember that it strangely enough verified closer to a La Ninaish Aleutian high! I did and posted an analysis here of all of them back to 2017-8. I’ll recheck it asap.

Followup: Regarding the hybrid that should keep the E coast safe from tropical, will it be safe from the hybrid, itself? This would be still another mess on the already hard hit NC coast! 18Z Euro: sfc: total rain thru 144 with some still falling near coast: winds:

Hey Charlie, As promised with the help of a Midwest pro met., here is the first response supporting the net benefit of CC to crops. This one covers soybeans (posts to cover other crops to come later): Let's separate out other factors(technology for instance), so that we can look only at the photosynthetic benefits from increasing CO2 to soybeans. Turns out that the impact of CO2 on soybeans has more studies than almost any other plant. Here's how to access the empirical evidence/data from the site that has more of it than any other. Please go to this link: http://www.co2science.org/data/data.php Go to plant growth data base: http://www.co2science.org/data/plant_growth/plantgrowth.php Go to plant dry weight(biomass): http://www.co2science.org/data/plant_growth/dry/dry_subject.php Pick the name of a plant, any plant and go to it based on its starting letter. Let's pick soybeans. Go to the letter S: http://www.co2science.org/data/plant_growth/dry/dry_subject_s.php Then scroll down and hit soybeans. This is what you get: http://www.co2science.org/data/plant_growth/dry/g/glycinem.php Look at the following screenshot for the table showing the large benefits of CO2 to soybeans:

I was wondering what’s the deal with that hybridish nor’easter offshore the E coast this weekend into next week? It’s on all 12Z major ops in one form or another. As you implied, the 12Z Euro has this, which had moved NNE from off the SE US and then turns sharply left into NJ in Sandy fashion:

Hey Charlie, I need to put a detailed post together about the net benefits of CC on crops and will do that ASAP!

What’s with that hybridish nor’easter offshore the E coast this weekend into next week? It’s on all 12Z major ops in one form or another.

12Z UKMET: further SW than 0Z as it goes WNW to Leewards and PR followed by NW and then NNW turn to near Erin’s position NE of Turks/Caicos (pretty weak and a little weaker than 0Z) with a safe recurve from the Conus as it is taken out by an upper trough: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 78 HOURS FORECAST POSITION AT T+ 78 : 13.6N 53.2W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 09.10.2025 84 14.2N 55.1W 1009 36 1200UTC 09.10.2025 96 15.4N 58.6W 1009 37 0000UTC 10.10.2025 108 16.5N 61.9W 1008 33 1200UTC 10.10.2025 120 17.1N 64.7W 1009 34 0000UTC 11.10.2025 132 18.9N 67.3W 1008 33 1200UTC 11.10.2025 144 20.5N 69.1W 1008 38 0000UTC 12.10.2025 156 22.3N 70.6W 1007 34 1200UTC 12.10.2025 168 24.2N 71.4W 1006 33 ————- Edit: Does anyone know how to save an image from Pivotal if not a member without having to do a screenshot?

Thanks for clarifying. Regarding MDR activity, 2025 sort of reminds me of a quieter version of these 3 years of the current active era that had all MDR TC origins recurve safely from the Conus: 1995: from MDR like Erin in 2025 only one was close (Emily); was also La Niña 2010: from MDR like Erin in 2025 only one was close (Earl); was also La Nina 2023: from MDR like Erin in 2025 only one was close (Lee) and similar to 2014: from MDR like Erin in 2025 only one was close (Bertha)

Followup to above post: Followup: rain became moderate to even heavy at times and more continuous the last few hours including some heavy rain in a thunderstorm a little while ago. But so far there’s been no flooding in my location as the totals appear to be no more than 1” so far. Now the precip. elements are moving more SE to NW.This FFW was released, mainly for N and W parts of my county as my area hasn’t had the 2-3” referenced:BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE CHARLESTON SC 1121 AM EDT SUN OCT 5 2025 THE NATIONAL WEATHER SERVICE IN CHARLESTON HAS ISSUED A * FLASH FLOOD WARNING FOR... CHATHAM COUNTY IN SOUTHEASTERN GEORGIA... * UNTIL 215 PM EDT. * AT 1121 AM EDT, DOPPLER RADAR INDICATED THUNDERSTORMS PRODUCING HEAVY RAIN ACROSS THE WARNED AREA. BETWEEN 2 AND 3 INCHES OF RAIN HAVE FALLEN. FLASH FLOODING IS ONGOING OR EXPECTED TO BEGIN SHORTLY. HAZARD...FLASH FLOODING CAUSED BY THUNDERSTORMS. SOURCE...RADAR INDICATED. IMPACT...FLASH FLOODING OF SMALL CREEKS AND STREAMS, URBAN AREAS, HIGHWAYS, STREETS AND UNDERPASSES AS WELL AS OTHER POOR DRAINAGE AND LOW-LYING AREAS. * SOME LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING INCLUDE... POOLER, I-16/I-95 INTERCHANGE, SAVANNAH INTERNATIONAL AIRPORT, GODLEY STATION, HUNTER ARMY AIRFIELD, DOWNTOWN SAVANNAH, GARDEN CITY, PORT WENTWORTH, BLOOMINGDALE AND MEINHARD. VERY HEAVY RAINFALL IS OCCURRING ACROSS NORTHERN CHATHAM COUNTY. THE SAVANNAH INTERNATIONAL AIRPORT MEASURED 1.53 INCHES IN AN HOUR AND OTHER AUTOMATED RAIN GAUGES IN THE AREA HAVE MEASURED NEARLY 3 INCHES OF RAIN SO FAR TODAY. @buckeyefan1please pin. TIA I ended up with 0.75” for the period starting Saturday night and ending at sunset yesterday (10/5).

New (Oct) Euro precip anomaly forecast for DJF: very slightly wetter in NE/SE and very slightly drier part of Midwest vs Sept outlook and similar to Oct ‘24 outlook for last winter/La Ninaish NN much of E US but BN signal deep SE with lack of dominant ST jet Sept ‘25 outlook for DJF: Last Oct precip for last winter:

More (2M temps) from brand new Euro winter outlook: Oct (brand new) is somewhat mild in much of US similar to Sept outlook with mainly ~2-3.5 F AN (vs 1993-2016 base) in much of the US and mainly ~2 F AN much of NE US and ~2.5-3 AN much of SE US with best chance closer to 1 AN N tier from Wash state to Lakes, where it cooled ~1F from Sept outlook: Sept outlook was similarly fairly mild in most of the US: For comparison, here was last Oct’s outlook for DJF 24-5: was actually slightly warmer in the NE and we know that verified to be much too warm most of US Actual DJF 2024-5: much colder than Oct Euro forecast! Was Oct ‘24 the warmest Oct. DJF forecast for the NE back to 2017? No, it actually was this one for 2020-1, which like 2024-5 verified to be significantly too warm most of US: Actual DJF 2020-1: significantly colder than Oct Euro forecast! @snowman19

Thanks for the reminder! Here are the last two runs of Euro DJF H5 maps to compare: October (just released): very La Ninaish…hopefully this will be wrong just like 2024-5 was! Most negative anomalies in N Hem west of Hudson Bay (Ninaish): September run for DJF: didn’t have as strong of an Aleutian ridge; E US ridge similar:

This is now Invest 95L: Tropical Weather Outlook NWS National Hurricane Center Miami FL 800 AM EDT Sun Oct 5 2025 For the North Atlantic...Caribbean Sea and the Gulf of America: 1. Tropical Atlantic (AL95): A broad area of low pressure associated with a tropical wave continues to produce a large area of disorganized showers and thunderstorms several hundred miles south-southwest of the Cabo Verde Islands. Environmental conditions appear conducive for additional development of this system, and a tropical depression is likely to form this week as the system moves quickly across the central tropical Atlantic, approaching portions of the Leeward Islands by the latter part of this week. * Formation chance through 48 hours...medium...40 percent. * Formation chance through 7 days...high...70 percent. @bigtenfan

The latest Euro Weeklies are the most active yet in the W Caribbean for the week of 10/13-19 (if I were in the FL pen., especially S half, I’d be pretty concerned for midmonth): Forecast nearby TC probabilities: Forecasted anomalies vs 2005-24 climo: wow!

The latest Euro Weeklies are the most active yet in the W Caribbean for the week of 10/13-19 (if I were in the FL pen., especially S half, I’d be a bit concerned for midmonth): Forecast nearby TC probabilities: Anomalies vs 2005-24 climo: wow!

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!