{ "number": 752, "headline": "September 30, 2025 Tuesday Weather Update", "standfirst": "Early October warmth for much of the Lower 48", "desk": "notebook", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2025-10-01", "published": "2025-10-01T00:27:34.053000Z", "updated": null, "access": "free", "body_html": "
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2025 Hurricane Season [Day 122]. My FORECAST for this year is (still) 14 named storms, 7 hurricanes, and 3 major hurricanes (near average)

2025 Season to Date: 9 Named Storms, 4 Hurricanes, and 3 Majors | ACE = 80

Good Evening! This is post 752 in this newsletter\u2019s brief history (~2 years). I\u2019m shifting back to full time USA weather coverage as winter is fast approaching, and that means snow and cold.

Mid-Level Water Vapor Loop

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IR Loop

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Medium and Range | AIFS 18z | 10-days Height Anomaly

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A powerful Canadian Arctic trough will connect with Humberto & Imelda and take them out to sea.

Strong ridging persists over the central U.S. into week 2 \u2014 with the Canadian Arctic \u201cpolar vortex\u201d showing signs of dipping into the Midwest and Great Lakes, but not quite yet! Instead, we\u2019ll have balmy early-October weather \u2014 otherwise quiet.

High Temperatures Next 9-days

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Weather Trader is a reader-supported newsletter authored by Dr. Ryan Maue. To receive new posts and support my work, consider becoming a free or paid subscriber.

Wednesday Low Temperatures

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A tiny % of New England below freezing \u2014 more chilly air back over Quebec and Ontario with strong Canadian Arctic trough

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Wednesday High Temperatures

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NOAA WPC 7-Day Precipitation

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Atlantic Basin Outlook | 8 PM ET Update

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NHC Track for Hurricane Humberto

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Hurricane Humberto IR and GeoColor Satellite

Humberto is firing very deep convection within a sheared environment \u2014 and looks more impressive than Imelda this evening

Hurricane Imelda | NHC Forecast Cone

978 mb \u2014 75 knot maximum sustained winds

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Imelda displaying a large, ragged eye like feature ESE of the main burst of convection

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ECMWF Next 10-Days Integrated Vapor Transport | 12z cycle

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ECMWF 18z Precipitable Water | Next 6-days | Humberto and Imelda

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ECMWF 18z Relative Vorticity | Next 6-days | Humberto and Imelda.

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Post-Tropical Humberto \u2014> Powerful Hurricane Force \u201cbomb cyclone\u201d

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Textbook 942 mb \u2014 \u201cwarm seclusion\u201d extratropical cyclone \u2014> 80-100 knot winds + gusts over the ocean \u2014> and perhaps hurricane force over British Isles into Friday and Saturday.

SST Analysis and Anomaly

Atlantic Satellite Images

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NOAA Tropical Surface Analysis | 18z

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Atlantic Tropical Waves = 2 but neither flagged as development potential by NHC

ECMWF EPS 12z | Active Storm Tracks Day 10

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ECMWF EPS 12z | Active Storm Tracks Day 15

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Still a LOT of random activity across the western half of the Atlantic basin through mid-October \u2014 including some Caribbean tracks likely emanating out of the Central American gyre \u2014 typical for early to mid October.

Eastern Pacific | Tropical Storm Octave (15E) + Disturbance (80%)

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Octave might be around for a week meandering over warm-enough water to keep convection alive.

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Burst of convection with Octave \u2014 the next disturbance likely a TD/TS by this weekend off coast of Mexico

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Western Pacific | Invest 93W \u2014> Philippines into South China Sea

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Another Typhoon landfall in China this weekend

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Maps sourced from weathermodels.com designed and innovated by yours truly! Please subscribe there for real-time access to the newest maps, charts from all of the weather models including ECMWF.

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A powerful Canadian Arctic trough will connect with Humberto & Imelda and take them out to sea.

Strong ridging persists over the central U.S. into week 2 \u2014 with the Canadian Arctic \u201cpolar vortex\u201d showing signs of dipping into the Midwest and Great Lakes, but not quite yet! Instead, we\u2019ll have balmy early-October weather \u2014 otherwise quiet.

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