Edition 2026-09-30 The Ledger Archive API RSS Weather Trader
Milepost
1250

TheForecast Post

A chronicle of American weather and climate  ·  Wednesday, 30 September 2026

Denver, Colorado Revisions MILEPOST 1249

Denver's forecast for Thursday has moved 8°F warmer

64°F in the 20260928T06:00Z run, 72°F in the 20260930T00:00Z — the 2nd-largest revision of the 6 cities on the roster that moved at all. The current run's 10th-to-90th percentile spread at that hour is 11°F.

Successive cycles do not merely refresh a forecast; they leave a trail. For Thursday, October 1 at 21Z in Denver, that trail runs from 64.0°F in the 20260928T06:00Z cycle to 72.3°F in the 20260930T00:00Z — a move of +8.3°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 Thursday at 21Z
api.weather.city /v1/history (nbm-qmd)
8.3 °F normal 0.0 °F · 2 of 6
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
11.1 °F normal 8.3 °F
current run
Milepost
1249 · laid 2026-09-30T10:25:14Z
Model
nbm-qmd · cycle 20260930T00:00Z
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
75bd3842ed4feedffe1cc2ba9ab4a028441b906dc268b7ad37cd5a003f0cf2b7
Machine
JSON