Edition 2026-09-25 The Ledger Archive API RSS Weather Trader
Milepost
1202

TheForecast Post

A chronicle of American weather and climate  ·  Friday, 25 September 2026

Dallas, Texas Revisions MILEPOST 1199

Dallas's forecast for Friday has moved 11°F colder

92°F in the 20260922T18:00Z run, 80°F in the 20260924T12:00Z — the largest revision of any city on the roster. The current run's 10th-to-90th percentile spread at that hour is 20°F.

Successive cycles do not merely refresh a forecast; they leave a trail. For Friday, October 2 at 18Z in Dallas, that trail runs from 91.6°F in the 20260922T18:00Z cycle to 80.3°F in the 20260924T12:00Z — a move of -11.3°F across 8 runs.

The change is about half the run's 10th-to-90th percentile spread, so the earlier forecast is still inside the current range of outcomes.

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 Friday at 18Z
api.weather.city /v1/history (nbm-qmd)
-11.3 °F normal 0.0 °F · 1 of 6
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
19.6 °F normal 11.3 °F
current run
Milepost
1199 · laid 2026-09-24T22:25:15Z
Model
nbm-qmd · cycle 20260924T12:00Z
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
0ddb8b29b8ad6cdf6b1d2a680ef377a198be6e4b9b0c138d834a2b735eaf299f
Machine
JSON