Edition 2026-09-16 The Ledger Archive API RSS Weather Trader
Milepost
1108

TheForecast Post

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

Nashville, Tennessee Revisions MILEPOST 1060

Nashville's forecast for Friday has moved 13°F warmer

81°F in the 20260910T12:00Z run, 93°F in the 20260911T18:00Z — the 3rd-largest revision of the 8 cities on the roster that moved at all. The current run's 10th-to-90th percentile spread at that hour is 17°F.

Successive cycles do not merely refresh a forecast; they leave a trail. For Friday, September 18 at 21Z in Nashville, that trail runs from 80.7°F in the 20260910T12:00Z cycle to 93.4°F in the 20260911T18:00Z — a move of +12.7°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 21Z
api.weather.city /v1/history (nbm-qmd)
12.7 °F normal 0.0 °F · 3 of 8
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
17.5 °F normal 12.7 °F
current run
Milepost
1060 · laid 2026-09-12T04:25:14Z
Model
nbm-qmd · cycle 20260911T18:00Z
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
ecac42c2eedb3782ae8cd66457c7ab73500b04c9490c1622041bb219195f0a98
Machine
JSON