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Milepost
1108

TheForecast Post

A chronicle of American weather and climate  ·  Wednesday, 16 September 2026

New York, New York Revisions MILEPOST 1075

New York's forecast for Tuesday has moved 9°F warmer

59°F in the 20260911T06:00Z run, 68°F in the 20260913T06:00Z — the 3rd-largest revision of the 9 cities on the roster that moved at all. The current run's 10th-to-90th percentile spread at that hour is 18°F.

Successive cycles do not merely refresh a forecast; they leave a trail. For Tuesday, September 22 at 12Z in New York, that trail runs from 59.2°F in the 20260911T06:00Z cycle to 67.7°F in the 20260913T06:00Z — a move of +8.5°F across 8 runs.

The change sits well inside the run's own spread, which is the guidance converging rather than reversing.

Model NBM-QMD, via api.weather.city /v1/history. Percentiles are the same run's own.

The numbers in this piece, with what they are measured against
forecast revision for Tuesday at 12Z
api.weather.city /v1/history (nbm-qmd)
8.5 °F normal 0.0 °F · 3 of 9
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
18 °F normal 8.5 °F
current run
Milepost
1075 · laid 2026-09-13T17:25:12Z
Model
nbm-qmd · cycle 20260913T06:00Z
Desk
revision v1
Method
the same valid time read from successive synoptic cycles; the move is last run minus first run
Source
https://api.weather.city/v1/history
Digest
db4b7d270008f8ef728b8116b3b49f0b8232e11b814b48f5b01e4037b8b9d167
Machine
JSON