{ "number": 705, "headline": "August 16, 2025 Erin Undergoing Eyewall Replacement", "standfirst": "Earlier Saturday, Erin reached Category 5", "desk": "notebook", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2025-08-17", "published": "2025-08-17T00:51:54.377000Z", "updated": null, "access": "free", "body_html": "
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2025 Atlantic Hurricane Season [Day 77]. My FORECAST for this year is 14 named storms, 7 hurricanes, and 3 major hurricanes.

2025 Season to Date: 5 named storms, 1 hurricanes, and 1 majors [ERIN +1]

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Saturday Evening Tropical Update

Good Evening! Hurricane Erin rapidly intensified to Category 5 with central pressure down to 915 mb \u2014 but has since come up this evening to 935 mb as an eyewall replacement cycle got underway.

No change to the track forecast reasoning: Erin will turn NW and gain latitude before taking a right turn out to sea well off the North Carolina coast.

Currently, Erin is hugging the 20\u00b0N latitude line & heading almost due westward.

ECMWF 18z | Precipitable Water Next 6-days

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My favorite parameter: through the next 6-days:

The furthest west that Erin should make is 73\u00b0W longitude with a sharper turn to the north in 3 days at 25\u00b0N latitude. While the ECMWF 18z didn\u2019t initialize the small inner-core of Erin very well, the model has been quite accurate in predicting the westward slide of Erin.

Initial MSLP in the model is 985 mb (biased 50 mb too high) but drops to 937 mb in 72-hours suggesting the storm will become a LOT larger and the central pressure in the 9-km model will be easier to resolve.

Most recent ECMWF 18z track for Erin

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Pressure of 952 mb in 5-days (Thursday afternoon) due east of North Carolina \u2026 and well west of Bermuda. Splits the uprights!

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Next 6-days of Vorticity

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Another wave that emerged off Africa heads westward through the MDR but does not develop \u2014 remaining diffuse and weak through 6-days. NHC has a 20% yellow hatching to watch in this coming week.

Atlantic Basin Outlook

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Category 4 Hurricane Erin

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NHC forecast maintains major hurricane status throughout the 5-day forecast, and it will become more MASSIVE in size. NHC discussion (5 PM): 

Although Erin is a somewhat compact hurricane now, the models are in\nstrong agreement that the system will grow in size over the next\nseveral days. In fact, by the middle of next week, Erin is forecast\nto at least double or triple in size, which will result in rough\nocean conditions over the western Atlantic.

ATCF Spaghetti | 18z Interpolated Models

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Some spread at 4-5 days as the parabolic track curves out to sea.

Atlantic Satellite Imagery | Infrared

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NOAA Tropical Surface Analysis | 18z

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Atlantic Tropical Waves = 2 + Major Hurricane Erin

Large View of Atlantic

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Africa Wave Train

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Plenty of \u201cseedlings\u201d lined up across tropical Africa \u2026 Erin is the first real success story.

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": "

2025 Season to Date: 5 named storms, 1 hurricanes, and 1 majors [ ERIN +1 ]

No change to the track forecast reasoning: Erin will turn NW and gain latitude before taking a right turn out to sea well off the North Carolina coast.

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