{ "number": 758, "headline": "October 6, 2025 Monday Evening Tropical Update", "standfirst": "Impactful coastal storm this weekend off Carolinas + Jerry", "desk": "tropics", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2025-10-07", "published": "2025-10-07T01:16:45.952000Z", "updated": null, "access": "free", "body_html": "
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2025 Hurricane Season [Day 128]. 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

Good Evening! This is post 758 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.

Fantasy Land GFS model at 12z \u2026 can\u2019t resist showing this scenario well over the forecast predictability horizon \u2014 heavy lake effect snow (feet) in the Great Lakes snowbelts on October 22 (!)

How can this happen? Cold air behind a strong Canadian Arctic cold front in the 20s and 30s \u00b0F blowing over the much warmer Great Lakes (60s) \u2026

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Yes, it can get pretty cold into the latter half of October \u2014 but not expecting this level of extreme cold \u2014 however, we should be ready for a pattern switch to cooler conditions once the record warmth departs.

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Canada already seeing substantial snowfall \u2026 and if we zoom out to the rest of North America (from ECMWF), we see the Arctic including Alaska well into winter weather season \u2026 15-day forecast also sees the Rocky Mountains with substantial snowfall.

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Central Atlantic Water Vapor + IR Satellite Images

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NHC has a 90% chance of development for Invest 95L \u2014 tropical wave in the central Main Development Region

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The environment in front of the storm (to the west) is rather dry in the mid-levels. Plus, from the NASA Dust loop, there is a fairly impressive Saharan Air Dust layer behind the tropical wave. Convection continues to fire, so the dry air doesn\u2019t seem to be counteracting instability or ascent + moisture availability.

Snapshot of Integrated Vapor Transport valid at 00z (Tuesday) shows plenty of moisture on the top half of the wave \u2014 and we just need a surface circulation to close off the low.

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NASA GEOS-5 | 5-day Dust Forecast

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This is a very strong \u2014 and unusual Saharan Air Layer + Dust outbreak in the Eastern Atlantic that will rotate anti-cyclonically to the west \u2014 just north of Invest 95L.

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

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  1. Large view centered on North America shows [Eastern Pacific] Hurricane Priscilla and its moisture plume heading into the American Southwest.

  2. Another system behind Priscilla \u2014> to become Raymond along the coast of Mexico

  3. In the Atlantic, Invest 95L reaches the northern Leeward Islands and comes apart in a very hostile environment \u2014> NHC at 90% chance of development

  4. Non-tropical trough \u2014> development of \u201chybrid system\u201d off the East Coast that could be impactful even if not a named storm (but it could be Karen)

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 that persists through 10-days

ECMWF EPS Temperature Anomaly | Next 15-days

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Ensemble mean shows cooler air through this weekend across the Midwest, Great Lakes, and Northeast behind a cold front / trough. But warmth builds again in the Central U.S. \u2014 but cooler out west into Week 2

ECMWF 18z Wind Gusts | Into this weekend | Next 3 to 6-days

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A Nor\u2019easter like hybrid system developing this weekend off the Carolinas

ECMWF 18z Precipitable Water | Next 6-days

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Major Canadian Trough bringing cooler and dryer air into the Eastern U.S. helps force the development of Southeast coastal low \u2014> which will push northward. Jerry is well to the east and by this weekend, poorly organized.

Note ECMWF is much faster with the movement of Invest 95L \u2014> Jerry

NOAA GFS 18z \u2014> East Coast \u201cNor\u2019easter\u201d Hybrid System

Slower movement of Jerry \u2014> more intense

Major coastal low \u2014> looks like a powerful (but rainy) Nor\u2019easter in a similar location as ECMWF 18z

NOAA WPC 7-Day Precipitation

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Atlantic Basin Outlook | 8 PM ET Update

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90% NHC \u2014 Invest 95L with risk to northern Leeward Islands and Northeast Caribbean in 3-4 days

Invest 95L ATCF Spaghetti

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I\u2019m discounting the western members mainly the HMON, HAFS-A and HAFS-B

ECMWF 18z Precipitable Water | Next 6-days

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Updated ECMWF 18z is only somewhat 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. Another tropical wave comes off Africa for this weekend.

NOAA GFS 186z | Integrated Vapor Transport

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GFS/GEFS = much more aggressive with development of Hurricane Jerry

NOAA GEFS 18z | Invest 95L | 31 Ensemble Members

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HAFS Hurricane Models | 12z Intensity Update | Major \u2014> Cat 4

HAFS Hurricane Models | 18z Intensity Update | Cat 1 Hurricane

\u2014> Uncertainty about intensity and therefore the ultimate track from the HAFS mesoscale model (A and B)

Range of outcomes from TS/Cat 1 to perhaps Category 5

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.

NOAA Tropical Surface Analysis | 18z

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Atlantic Tropical Waves = 3 with Invest 95L \u2014 red 90% {HIGH chance)

ECMWF EPS 12z | All Storm Tracks Day 6

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Most members develop Invest 95L \u2026 with a range of intensity outcomes

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

ECMWF EPS 12z | All Storm Tracks Day 15

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Some weak TS tracks in the Caribbean + 2 more intense out of 51 members in the Gulf of Mexico \u2014> we shift focus to the western half of the Atlantic basin through October as the Cape Verde season winds down.

Nothing imminent or threatening after Jerry \u2014 and whatever develops off the Carolinas.

Eastern Pacific Tropical Weather Outlook | 8 PM ET

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Tropical Storm Octave and large Hurricane Priscilla + Next System (70% \u2014> Raymond)

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Another system \u2014 Raymond will likely follow along the coast of Mexico (60%)

Hurricane Priscilla | NHC Cone | 85 mph Category 1

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Priscilla still 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.

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

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

Western Pacific Typhoon Season | 28W (Halong) and 95W (Invest)

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Potential Super Typhoon Halong (28W)

Massive typhoon \u2014 should reach 130-knots over warm waters well south of Japan. The storm will loop/curve out to sea and surely miss Japan.

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Satellite shows a compact and powerful Typhoon with a clearing/warm eye = T 6.0 and about 115-knots (Category 4)

ECMWF 18z | Next 6-days Precipitable Water

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Google Deep Mind 12z | Ensemble Tracks for Halong

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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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Fantasy Land GFS model at 12z \u2026 can\u2019t resist showing this scenario well over the forecast predictability horizon \u2014 heavy lake effect snow (feet) in the Great Lakes snowbelts on October 22 (!)

How can this happen? Cold air behind a strong Canadian Arctic cold front in the 20s and 30s \u00b0F blowing over the much warmer Great Lakes (60s) \u2026

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