{ "number": 756, "headline": "October 5, 2025 Sunday Tropical Update", "standfirst": "NHC up to 70% chance of Tropical Storm Jerry formation in central Atlantic", "desk": "tropics", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2025-10-06", "published": "2025-10-06T01:32:25.847000Z", "updated": null, "access": "free", "body_html": "
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2025 Hurricane Season [Day 127]. My FORECAST for this year is 14 named storms, 7 hurricanes, and 3 major hurricanes (near average)

2025 Season to Date: 9 Named Storms, 4 Hurricanes, and 3 Majors

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Hurricanes Octave and Priscilla

Good Evening! This is post 756 in this newsletter\u2019s brief history (~2 years). With winter fast approaching, we\u2019ll be transitioning to coverage of cold and snow \u2014 but also stay with the tropics as activity seems to be heating up.

Weather Trader is a reader-supported newsletter with daily weather updates. To receive new posts and support my work, consider becoming a free or paid subscriber.

Mid-Level Water Vapor Loop | Atlantic Basin

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While the Atlantic is currently quiet, NHC is continuing to watch an active tropical wave with some convection bubbling up late tonight. NHC has a 70% chance of development in 7-days.

The environment in front of the storm is rather dry in the mid-levels. However, as we\u2019ll see from the NASA Dust loop, there is a fairly impressive Saharan Air Dust layer behind the tropical wave that may be signaling to ECMWF model to tamp down expectations of a powerful Hurricane Jerry.

The GFS/GEFS systems + Mesoscale models are ALL in agreement on Major Hurricane Jerry \u2014 while the ECMWF/EPS system is a coin flip for no development vs. major hurricane.

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

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Large view centered on North America shows the eventual dissipation of Hurricane Octave in the wake of Eastern Pacific]Hurricane Priscilla with moisture heading into the U.S. Southwest \u2014 also absorbing what\u2019s left of Octave, and then being followed by Raymond *60% chance NHC).

The flagship 12z model run from ECMWF shows a weaker reflection of Tropical Storm Jerry developing east of the Lesser Antilles and heading near/through the Northeast Caribbean through 5-6 days.

Tropical storm development chance is increasing \u2014 now up to 70% chance but uncertainty about the intensity \u2014 large range from minimal TS to Category 5.

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

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Central U.S. ridging (and warmth) in the story of the next 10-days with troughs on either side. This is a persistent pattern \u2014 may need a recurving Typhoon to help rejigger the North Pacific jet stream and downstream Rossby waves.

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.

NOAA WPC 7-Day Precipitation

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Atlantic Basin Outlook | 8 PM ET Update

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70% NHC \u2014 Invest 95L with risk to Lesser Antilles and Northeast Caribbean in 4-5 days | Invest 95L ATCF \u2014>

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ECMWF 18z Precipitable Water | Next 6-days

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Updated ECMWF 18z is barely interested in the small vortex from Invest 95L and only minimally develops it into a TD/TS before merging with a frontal boundary in the subtropics. A strong African dust / Saharan Air Layer clears out the MDR like an eraser.

NOAA GFS 18z | Integrated Vapor Transport

GFS/GEFS = very aggressive with development of Major Hurricane Jerry

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NOAA GEFS 18z | All Cyclone Tracks | 31 Ensemble Members

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HAFS Hurricane Models | 18z Intensity Update

Major hurricane \u2014 but a small inner-core

NASA Dust Forecast | Next 5-days

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Impressive Saharan dust layer!

SST Analysis and Anomaly | 12z

Passage of Imelda and Humberto took a huge bite out of the water temperature along the U.S East Coast to Bermuda with sub-26\u00b0C water and a remarkable \u201ccold wake\u201d that probably won\u2019t recover heading through October.

Gulf of Mexico and Caribbean remain warm \u2026 with 28\u00b0C+ into the MDR = wide open for business.

Atlantic Satellite Image | IR

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Areas of convection including 3 tropical waves \u2014 with Invest 95L showing some showers and thunderstorms.

NOAA Tropical Surface Analysis | 18z

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Atlantic Tropical Waves = 3 with Invest 95L \u2014 red 70%

Eastern Atlantic Night Pseudo-Visible Satellite Image | Invest 95L

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ECMWF EPS 12z | Active Storm Tracks Day 7

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Still around 50% chance of developing Invest 95L from EPS 12z \u2014 full physics.

Non-tropical area of low-pressure off the East Coast could be impactful..

ECMWF EPS 12z | Active Storm Tracks Day 10

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Need to keep an eye on the western Caribbean and whatever might spin out randomly of the Central American Gyre.

ECMWF EPS 12z | Active Storm Tracks Day 14

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Comparison with AIFS-ENS | 18z | Day 6 All Storm Tracks

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Not all of the members trigger a track with Invest 95L but more than conventional model \u2026 also see the East Coast system tracks

Eastern Pacific Tropical Weather Outlook | 8 PM ET

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Busy \u2014 2 hurricanes: small Octave and large Priscilla

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Another system \u2014 Raymond will likely follow along the coast of Mexico

Hurricane Octave | NHC Cone | 80 mph Category 1

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Hurricane Priscilla | NHC Cone | 75 mph Category 1

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Could become a major hurricane heading slowly NW to west of Baja California in next several days. Moisture from the remnants will likely head into the U.S. Southwest in a week.

Eastern Pacific Current Satellite

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Priscilla significantly larger than Octave.

PWAT Next 6-days for Octave and Priscilla \u2014 then Raymond!

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Surge of PWAT through Gulf of California into Southern California and Arizona \u2014 and Raymond on its heels

Western Pacific Typhoon Season + Northern Indian Ocean Cyclones

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A Hurricane developed in the Arabian Sea but has since nearly sputtered out over cooler water and very stable/dry atmospheric conditions east of Oman. It will dissipate in the coming couple days.

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Potential Super Typhoon Halong (28W)

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Massive typhoon \u2014 could reach 130-knots (I think) over warm waters well south of Japan. The storm will loop/curve out to sea and likely miss Japan.

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ECMWF 12z | Ensemble Tracks for Halong

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Interesting track for Halong \u2014 comes very close the Japan with the ECMWF 12z flagship model \u2014 but at this juncture \u2014 misses landfall \u2014 barely.

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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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While the Atlantic is currently quiet, NHC is continuing to watch an active tropical wave with some convection bubbling up late tonight. NHC has a 70% chance of development in 7-days.

The environment in front of the storm is rather dry in the mid-levels. However, as we\u2019ll see from the NASA Dust loop, there is a fairly impressive Saharan Air Dust layer behind the tropical wave that may be signaling to ECMWF model to tamp down expectations of a powerful Hurricane Jerry.

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