September 20, 2023 Hurricane Season
Models confused about African easterly wave development
September 2023 was the 9th-warmest September in the 131-year national record (1895–2025), at 67.7°F against a 1991–2020 normal of 66.0°F (+1.8°F).
September 2023 was the 27th-driest September in the 131-year national record (1895–2025), at 2.1in against a 1991–2020 normal of 2.6in (-0.4in).
NOAA/NCEI Climate at a Glance, contiguous United States. This is the observed record for the month, not a score of anything said in this piece — the forecast ledger begins 2026-08-17 and cannot reach earlier posts.
GFS 18z is into the 980s mb with the coastal storm that starts out as Subtropical but could transition into a fully tropical system prior to landfall. This looks like Ophelia by late Friday or early Saturday, although NHC is only at 40% chance of development.
The storm will start forming during the latter half of Thursday east of Florida. I suspect we will have a Potential Tropical Cyclone alert in the next 24-36 hours.
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- 103 · laid 2023-09-20T22:24:36.337000Z
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