GaWx

0Z UKMET: landfall ~175 miles W of 12Z run with it near far SE LA and then MS. Strongest run yet with high end TS/990 mb: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 54 HOURS FORECAST POSITION AT T+ 54 : 22.2N 92.1W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 08.10.2026 60 22.7N 91.7W 1003 30 0000UTC 09.10.2026 72 22.9N 89.9W 1001 30 1200UTC 09.10.2026 84 25.4N 88.6W 999 39 0000UTC 10.10.2026 96 26.4N 88.5W 997 48 1200UTC 10.10.2026 108 29.2N 88.7W 990 58 0000UTC 11.10.2026 120 32.1N 89.5W 992 29 1200UTC 11.10.2026 132 33.8N 88.8W 1002 25 0000UTC 12.10.2026 144 38.4N 83.2W 1003 12 1200UTC 12.10.2026 156 CEASED TRACKING

Today’s Euro weekly for 10/5-11 is the final one: Look how much the cold signal for 10/5-11 in the E weakened overall over the last 10 days. However, the signal remained at about the same level in from the NE to down the coast NYC to Hatteras: Sep 25th run for 10/5-11: much stronger cold signal Week 2 (10/12-18) is warm. Just a few days ago it was cool. Other than week 1, the only other cool E weak is week three, 10/19-25: this week has been mainly coolish over the last week of runs:

Today’s NOAA weekly relative ENSO release for last week: 23SEP2026 3.9 3.1 2.2 0.1 30SEP2026 4.5 3.3 2.3 0.1 Nino 1+2 warmed up strongly (0.6) to +4.5! For the week, it obliterates the prior record back to 1981 of +3.5 (1997). It is only barely shy of the all time record for any week of +4.6 (6/29/1983). Nino 3 warmed up by 0.2 to +3.3. That’s a new record high for the week with it beating the +2.8 of 1997. The record for any week is +3.6 (12/29/1982). Nino 3.4 warmed slightly to +2.3. This barely beats the +2.2 of 1982 for the week. The warmest for any week is +2.9 (12/29/82). Nino 4 remained at only +0.1, which in combo with the way warmer Nino 3 and Nino 1+2, makes ‘26 easily the most E based Nino on record. https://www.cpc.ncep.noaa.gov/data/indices/rel_wksst9120.txt

60%/80% now: Tropical Weather Outlook NWS National Hurricane Center Miami FL 200 PM EDT Mon Oct 5 2026 For the North Atlantic...Caribbean Sea and the Gulf of America: 1. Southwestern Gulf of America (AL92): A trough of low pressure over the southwestern Gulf of America is producing disorganized showers and thunderstorms. Although environmental conditions appear to be marginally conducive, gradual development is becoming more likely, and a tropical depression is expected to form during the middle portion of the week. This system is expected to drift eastward over the next couple of days, before it turns northward. It is too early to determine the specific impacts to the northern Gulf Coast, but interests there should closely monitor the progress of this system. * Formation chance through 48 hours...medium...60 percent. * Formation chance through 7 days...high...80 percent.

12Z UKMET: shifts back east from 0Z run’s far SE LA to MS/AL border track to new track into FL Pan for mid-grade TS followed by NNE and then NNW move in AL: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 66 HOURS FORECAST POSITION AT T+ 66 : 22.8N 92.4W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 08.10.2026 72 24.0N 91.4W 1002 30 0000UTC 09.10.2026 84 25.2N 89.4W 999 34 1200UTC 09.10.2026 96 26.7N 88.0W 996 44 0000UTC 10.10.2026 108 28.7N 86.9W 995 49 1200UTC 10.10.2026 120 32.1N 86.1W 999 26 0000UTC 11.10.2026 132 34.5N 87.3W 1001 26 1200UTC 11.10.2026 144 CEASED TRACKING

The thread for the Gulf tropical threat has been started:

We’re almost certainly heading for the most E based Nino on record for good or for bad. The SE ridge should be held back bigly, which would be really good from my perspective.

Thanks, Mitch. Here are the Euro Oct progs for winter going back to 2017-8 for comparison purposes and how they did in the E US: 2026: 2025: much too warm 2024: much too warm 2023 (Nino): too cold 2022: too cold (not warm enough) 2021: net slightly too warm (close SE, too warm NE) 2020: net too warm (much too warm SE; avg of too warm NE but close N Eng) 2019: pretty close (slightly too cold SE but close NE) 2018 (Nino): net too cold (close NE but much too cold SE): 2017: close ———————— Tally: -did well in 19 and esp. 17 -did pretty well 21 -did pretty badly 23, 22, 20, 18 -did terribly 25, 24 -too cold both El Niños in SE and 1 of 2 in NE -NE: too warm on 4, close on 3, too cold on 2 -SE: too warm on 3, close on 2, too cold on 4

Indeed! Model consensus has plentiful to possibly even flooding rains (especially on/near the Gulf coast) in some areas of the SE this weekend! There will likely be a dedicated thread in the Tropical section for this soon: Now cherry (30%/70%): Tropical Weather Outlook NWS National Hurricane Center Miami FL 800 AM EDT Mon Oct 5 2026 Southwestern Gulf of America: A trough of low pressure in the southwestern Gulf of America is producing disorganized showers and thunderstorms. Although environmental conditions appear to be marginally conducive, gradual development is becoming more likely, and a tropical depression is likely to form during the middle or latter portion of the week. This system is expected to drift eastward over the next few days, before it turns northward. * Formation chance through 48 hours...low...30 percent. * Formation chance through 7 days...high...70 percent.

Now cherry (30%/70%): Tropical Weather Outlook NWS National Hurricane Center Miami FL 800 AM EDT Mon Oct 5 2026 Southwestern Gulf of America: A trough of low pressure in the southwestern Gulf of America is producing disorganized showers and thunderstorms. Although environmental conditions appear to be marginally conducive, gradual development is becoming more likely, and a tropical depression is likely to form during the middle or latter portion of the week. This system is expected to drift eastward over the next few days, before it turns northward. * Formation chance through 48 hours...low...30 percent. * Formation chance through 7 days...high...70 percent.

Up to 10/50% as of 1AM CDT advisory: Tropical Weather Outlook NWS National Hurricane Center Miami FL 200 AM EDT Mon Oct 5 2026 For the North Atlantic...Caribbean Sea and the Gulf of America: 1. Southwestern Gulf of America: A surface trough of low pressure has developed along the coast of Mexico in the southwestern Gulf of America. Although environmental conditions are expected to be only marginally conducive, gradual development of this system is possible and a tropical depression could form by the second half of this week while it initially drifts eastward before turning northward. * Formation chance through 48 hours...low...10 percent. * Formation chance through 7 days...medium...50 percent. Forecaster Papin

Agree 100%. Now will they be T, ST, or ET legs? I think T legs most likely and ET least likely. Speaking of T legs: 0Z UKMET: 5th run in a row with a Gulf TC with it maxing at a mid level TS and land falling over tip of SE LA followed by MS/AL border on Saturday with plentiful rains and even some areas of flooding rains over the SE US over weekend with heaviest Gulf coast: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 84 HOURS FORECAST POSITION AT T+ 84 : 23.2N 91.7W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 08.10.2026 84 23.2N 91.7W 1004 28 0000UTC 09.10.2026 96 22.8N 91.3W 1003 26 1200UTC 09.10.2026 108 25.3N 90.3W 1003 35 0000UTC 10.10.2026 120 26.4N 90.7W 1000 38 1200UTC 10.10.2026 132 29.0N 89.5W 998 45 0000UTC 11.10.2026 144 33.4N 88.1W 992 27 1200UTC 11.10.2026 156 35.4N 87.9W 1002 18 0000UTC 12.10.2026 168 CEASED TRACKING

Sunday had a rainy late afternoon and evening, but it was very light. It’s still raining. Total measured only ~0.1”, which gets me to a MTD of ~2.2”. Edit: 8:38AM Mon 10/5: I’ve been getting good rains the last 45 minutes. Edit 7:30PM: Today (10/5) I received ~0.5”, including those good rains between 7:45 and 8:45AM. That puts me at an impressive ~2.7” MTD and matches the model consensus based expectation.

Here’s the breakdown of Oct vs DJF NAO for +1.4+ Ninos since 1950: 2023: - + 2015: + + 2009: - - 1997: - N 1991: N + 1986: + - 1982: - + 1972: + + 1965: + - 1957: + - So, of the 5 +Oct, DJF was - thrice and + twice fwiw

‘23 JJAS PDO -2.4 ‘26 JJAS PDO -1.2