Edition 2026-09-25 The Ledger Archive API RSS Weather Trader
Milepost
1208

TheForecast Post

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

Nashville, Tennessee Revisions MILEPOST 1207

Nashville's forecast for Tuesday has moved 12°F colder

83°F in the 20260924T12:00Z run, 71°F in the 20260925T00:00Z — the 2nd-largest revision of the 7 cities on the roster that moved at all. The current run's 10th-to-90th percentile spread at that hour is 21°F.

Successive cycles do not merely refresh a forecast; they leave a trail. For Tuesday, October 6 at 00Z in Nashville, that trail runs from 82.9°F in the 20260924T12:00Z cycle to 71.3°F in the 20260925T00:00Z — a move of -11.5°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 Tuesday at 00Z
api.weather.city /v1/history (nbm-qmd)
-11.5 °F normal 0.0 °F · 2 of 7
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
20.9 °F normal 11.5 °F
current run
Milepost
1207 · laid 2026-09-25T10:25:14Z
Model
nbm-qmd · cycle 20260925T00:00Z
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
59d34ca3870deb67396cc65fbd1079cc483600cf49f5551ca4c2a8f8c86ebaf4
Machine
JSON