{ "number": 736, "headline": "September 16, 2025 Tuesday Morning Hurricane Season", "standfirst": "Invest 92L likely to become a tropical depression within next day or two", "desk": "tropics", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2025-09-16", "published": "2025-09-16T12:36:10.376000Z", "updated": null, "access": "free", "body_html": "
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Good Morning!

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Good morning! Invest 92L is quite impressive this morning \u2014 a marked change from the Atlantic basin doldrums we\u2019ve seen over the past weeks since Hurricane Erin.

The system is showing convective banding and bursts of thunderstorms in clusters. While not terribly well organized, there is large cyclonic circulation. This sprawling initial size will probably mean slow but steady intensification into a hurricane over the next 4-5 days.

Invest 92L will become Tropical Storm Gabrielle and has the potential to become another Major Hurricane \u2014 perhaps Category 4+ over the very warm waters of the west Atlantic warm pool. However, highly unlikely to be a direct impact to land including the Eastern U.S.

Another tropical wave will emerge off African coast (2nd in a parade) and currently has a 20% chance of developing according to the fresh NHC 8 AM outlook.

Atlantic Infrared Satellite Loop

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North America Precipitable Water | Next 6-days

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The Eastern Pacific off the coast of Mexico and Baja California remains active with Tropical Storm Mario holding on (barely) over cooler ocean waters. The next system already is designated Invest 96E and will be named Narda following in a similar track as Mario.

By Day 6, Hurricane Gabrielle will cross 60\u00b0W longitude but slow down considerably before being quickly swept out to sea ahead of a trough. By this time, the system could be a major hurricane.

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Atlantic Basin Outlook | 8 AM ET Update

2025 Hurricane Season [Day 108]. My FORECAST for this year is (still) 14 named storms, 7 hurricanes, and 3 major hurricanes (near average)

2025 Season to Date: 6 named storms, 1 hurricanes, and 1 majors | ACE = 40 ACE of Erin: 32.2 (140-knots maximum wind)

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Invest 92L \u2014> 90% chance of development + a new \u201carea of interest\u201d at 20% through 7-days.

Invest 92L ATCF Spaghetti

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Through Day 7, we can see the northward turn \u2014> out-to-sea \u201cfish mixer'\u201c

ECMWF 12-Days Integrated Vapor Transport | 00z cycle

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Another hurricane could form behind Gabrielle out of one several waves emerging off the African coast in sequence over the next few days. Then, looks like a break in the action in the Main Development Region (MDR) into end of September.

Atlantic Basin | ECMWF 06z | Precipitable Water Next 6-days

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Wave train is nicely set up into this weekend. Gabrielle should be underway by then while we watch 2 other waves with potential.

ECMWF 06z | +6 Days MSLP | UV850 | PWAT

Gabrielle likely to be a major hurricane within 6-days

HAFS A and HAFS B mesoscale models (06z) are mixed with Category 1 to 2 intensity at Day 5.

Atlantic Satellite Imagery | GeoColor and Infrared

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Water Vapor | Mid-level

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The upper-level low (trough) has moved SW just to the northwest of Invest 92L but so far seems to be helping with upper-level diffluence.

SST and SST Anomaly | ECMWF 12:00 UTC Forecast

Warm pool 28\u00b0 to 29\u00b0C plenty sufficient for any category of hurricane along the entire track of Invest 92L \u2014> Gabrielle

NOAA Tropical Surface Analysis | 06z

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Atlantic Tropical Waves = 4 \u2026 including Invest 92L (90% NHC area of interest)

Eastern Atlantic and Africa Visible Satellite

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ECMWF EPS 00z Ensemble | All Cyclone Tracks Through 5-days

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Some ensemble members showing major intensity surface pressure by Day 5 \u2026 not much along track spread, tightly clustered

ECMWF EPS 00z Ensemble | All Cyclone Tracks Through 10-days

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Only 2 members decide to leave the pack and head westward \u2026 but those eventually recurve out to sea as well.

ECMWF EPS 00z Ensemble | All Cyclone Tracks Through 15-days

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We need to keep an eye on the Caribbean and Gulf of Mexico for \u201cCentral American Gyre\u201d spawned systems.

AIFS-ENS Comparison at 00z | Active Tracks at Day 8

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AIFS-ENS Comparison at 00z | Active Tracks at Day 15

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A few members show something in the Gulf of Mexico \u2014 way over the \u201cforecast horizon\u201d but still a signal we need to watch closely heading into October.

AIFS-ENS 06z | 15-day Loop of Active Cyclones

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Busy Atlantic during the next 2-weeks with potential for 1-3 named tropical systems

Eastern Pacific Tropical Update | Tropical Storm Mario

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Mario is puffing a tiny burst of convection this morning so it remains a tropical storm. The next system is Invest 96E \u2014> Narda.

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HAFS mesoscale models with TS and Hurricane intensity solutions in next few days.

Western Pacific Typhoon Season Update

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TD 23W is underway + Invest 90W \u2014 potential for a Super Typhoon in a week.

ECMWF 06z | 6-days Snapshot | UV850 | PWAT | MSLP

Integrated Vapor Transport | Next 9-days

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TD 23W remains a tropical storm according to JTWC, but if it avoids land, then I\u2019d lean to a Typhoon

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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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The system is showing convective banding and bursts of thunderstorms in clusters. While not terribly well organized, there is large cyclonic circulation. This sprawling initial size will probably mean slow but steady intensification into a hurricane over the next 4-5 days.

Invest 92L will become Tropical Storm Gabrielle and has the potential to become another Major Hurricane \u2014 perhaps Category 4+ over the very warm waters of the west Atlantic warm pool. However, highly unlikely to be a direct impact to land including the Eastern U.S.

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