September 12, 2023 Hurricane Season
Hurricane Lee to transition post-tropical this weekend prior to landfall
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.
Hurricane Lee has maintained major hurricane intensity just barely (100-knots) and may be evolving into a bigger storm — with larger diameter eye — typical of storms approaching higher latitudes where environment is drier and more stable. Eventually Lee will encounter strong wind shear over cooler water and begin process of extratropical transition (ET). The NHC forecast is for Lee to complete ET prior to the center (lowest pressure) making landfall in Nova Scotia late Saturday/early Sunday.
The 00Z ECMWF HRES track of Lee was into Maine but the initial pressure and now 12-hour forecast was way too intense with pressure to 915 mb. That obviously did not occur with HRES and there are many EPS members that mimic the outlandish intensity of Lee. These then cluster into Maine. The EPS mean is dragged to the left as well.
The rest of this piece is for paid subscribers of Weather Trader. The Post keeps the archive, the index and the record; the writing itself stays behind the same subscription it was published under.
Read the full piece →- Milepost
- 97 · laid 2023-09-12T12:57:52.551000Z
- Source
- https://weather.substack.com/p/september-12-2023-hurricane-season
- Digest
- 97461064a89f18ebee1a6f43cefc35dd8f199e52fb0758d318cde8699b75bbc5
- Machine
- JSON