{ "number": 743, "headline": "September 23, 2025 Tuesday Evening Update", "standfirst": "Twin hurricanes could develop with a risk to US East Coast", "desk": "tropics", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2025-09-24", "published": "2025-09-24T00:45:11.956000Z", "updated": null, "access": "free", "body_html": "
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2025 Hurricane Season [Day 115]. My FORECAST for this year is (still) 14 named storms, 7 hurricanes, and 3 major hurricanes (near average)

2025 Season to Date: 7 Named Storms, 2 Hurricanes, and 2 Majors | ACE = 54

Good Evening! Atlantic hurricane season becoming quite busy over the next week or so with at least 2 more named storms \u2014 and both may become strong hurricanes. There is a risk for U.S. East Coast impacts from at least one of the systems \u2014 currently designated Invest 93L and Invest 94L \u2014 but we won\u2019t know which one gets Humberto or Imelda naming rights. Holding patten until storm(s) formation occurs.

Hurricane Gabrielle is still a major hurricane as of 8 PM ET moving eastward across the central North Atlantic. The eye has become cloud filled an more ragged as the hurricane weakens over cooler ocean waters within a more stable and dry environment.

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Atlantic Basin Outlook | 8 PM ET Update

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NHC has Invest 94L up to 70% development within next 7-days + Invest 93L to the right/east at 90%

Invest 93L with similar NW track as Gabrielle

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Invest 94L more uncertain WNW track through northern Caribbean into the Bahamas in next 5-days

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Not much model guidance yet for 93L \u2014 more will be available tomorrow from the suite of hurricane models.

Category 3 Hurricane Gabrielle (110-knots | 953 mb)

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Post-tropical storm by Friday \u2014 may landfall Portugal this weekend but much weaker

Category 3 Hurricane Gabrielle (07L) ATCF Spaghetti

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ECMWF Ensembles 12z | Gabrielle

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Medium and Extended Range

ECMWF 12-Days Integrated Vapor Transport | 12z cycle

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Flagship model at 12z through 12-days shows both Humberto (93L) and Imelda (94L) becoming hurricanes \u2026 but remaining separated and not interacting.

Humberto leaves to the ENE out to sea but Imelda is left behind to spin off the East Coast. Further in the future, it eventually heads out to sea with another trough.

UNCERTAINTY = HIGH \u2014 this is just one of hundreds of potential forecast ensemble scenarios we\u2019ll see in the next several days.

ECMWF 18z Precipitable Water | Next 6-days

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Most recent 18z cycle of the ECMWF (flagship) model has both Humberto and Imelda (hard to predict naming here) gaining latitude together side by side through Monday

HIGH uncertainty \u2014 but interests along the U.S. East Coast should monitor BOTH systems which may interact

ECMWF 18z Cyclonic Relative Vorticity | Next 6-days

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Atlantic Satellite Imagery | Infrared + Water Vapor + Night GeoColor

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NOAA Tropical Surface Analysis | 12z

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Atlantic Tropical Waves = 4 including two being watched with HIGH chance of development: Invest 93L and Invest 94L

Sea Surface Temperature + Anomaly | ECMWF 12z

Anomalously warm water centered upon Bermuda above 30\u00b0N \u2014 coincidentally along the path of Gabrielle and following system (Humberto or Imelda)

ECMWF EPS 12z Ensemble | All Cyclone Tracks Through 5.5-days

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ECMWF EPS 12z Ensemble | All Cyclone Tracks Through 7-days

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Threat to the U.S. Southeast \u2014> Carolinas + Virginia coastline by 7-days from 94L

ECMWF EPS 12z Ensemble | All Cyclone Tracks Through 10-days

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Highly chance of both systems developing into Hurricanes \u2014 with major intensity on the table. However, we\u2019ll need to wait until formation occurs before making any impacts forecasts \u2014 very complicated because there are 2 storms!

AIFS-ENS Comparison at 12z | All tracks at Day 6

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AIFS-ENS Comparison at 12z | All tracks at Day 8

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AIFS-ENS Comparison at 06z | All tracks at Day 10

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Eastern Pacific Tropical Update | Hurricane Narda

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Hurricane Narda | Category 1

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Forecast to reach near major hurricane strength over warm water of Eastern Pacific well away from Mexico.

Western Pacific Typhoon Season Update

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Category 4 Typhoon RAGASA (24W)

115-knots \u2014 Category 4 with a ragged eye

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Ragasa is tracking south of Hong Kong and will maintain Major Typhoon intensity as it makes landfall down the China coastline on Wednesday.

BUALOI (26W) has been designated \u2014 expected to become a Typhoon prior to impacting the Philippines in a couple of days.

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ECMWF 18z Precipitable Water | Next 6-days

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East of Japan, Typhoon Neoguri will eventually move into the North Pacific once another trough comes by to whisk it away.

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.

", "body_key": null, "teaser_html": "

Good Evening! Atlantic hurricane season becoming quite busy over the next week or so with at least 2 more named storms \u2014 and both may become strong hurricanes. There is a risk for U.S. East Coast impacts from at least one of the systems \u2014 currently designated Invest 93L and Invest 94L \u2014 but we won\u2019t know which one gets Humberto or Imelda naming rights. Holding patten until storm(s) formation occurs.

Hurricane Gabrielle is still a major hurricane as of 8 PM ET moving eastward across the central North Atlantic. The eye has become cloud filled an more ragged as the hurricane weakens over cooler ocean waters within a more stable and dry environment.

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