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 1081

Nashville's forecast for Sunday has moved 10°F warmer

85°F in the 20260912T00:00Z run, 94°F in the 20260914T00:00Z — the 2nd-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 11°F.

Successive cycles do not merely refresh a forecast; they leave a trail. For Sunday, September 20 at 18Z in Nashville, that trail runs from 84.5°F in the 20260912T00:00Z cycle to 94.2°F in the 20260914T00:00Z — a move of +9.7°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 Sunday at 18Z
api.weather.city /v1/history (nbm-qmd)
9.7 °F normal 0.0 °F · 2 of 8
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
10.8 °F normal 9.7 °F
current run
Milepost
1081 · laid 2026-09-14T10:25:12Z
Model
nbm-qmd · cycle 20260914T00:00Z
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
0285fa56f1949c497058e39f0d230fcd6365d6f3d22c2d4f8375debfee9a0c42
Machine
JSON