Edition 2026-09-25 The Ledger Archive API RSS Weather Trader
Milepost
1211

TheForecast Post

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

Nashville, Tennessee Revisions MILEPOST 1210

Nashville's forecast for Tuesday has moved 13°F colder

83°F in the 20260924T12:00Z run, 70°F in the 20260925T06:00Z — 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 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 69.5°F in the 20260925T06:00Z — a move of -13.3°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 Tuesday at 00Z
api.weather.city /v1/history (nbm-qmd)
-13.3 °F normal 0.0 °F · 2 of 6
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
20.8 °F normal 13.3 °F
current run
Milepost
1210 · laid 2026-09-25T16:25:16Z
Model
nbm-qmd · cycle 20260925T06:00Z
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
ec92b5c7010695566af692c0c1ea998b68d611319119d9161a1184f68a635210
Machine
JSON