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 1074

Nashville's forecast for Monday has moved 11°F warmer

61°F in the 20260911T06:00Z run, 72°F in the 20260913T06:00Z — the 2nd-largest revision of the 9 cities on the roster that moved at all. The current run's 10th-to-90th percentile spread at that hour is 14°F.

Successive cycles do not merely refresh a forecast; they leave a trail. For Monday, September 21 at 12Z in Nashville, that trail runs from 60.8°F in the 20260911T06:00Z cycle to 71.8°F in the 20260913T06:00Z — a move of +11.0°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 Monday at 12Z
api.weather.city /v1/history (nbm-qmd)
11 °F normal 0.0 °F · 2 of 9
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
14.2 °F normal 11.0 °F
current run
Milepost
1074 · laid 2026-09-13T17:25:12Z
Model
nbm-qmd · cycle 20260913T06:00Z
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
0478ea23100d3d2dfc80f44453cde267b94312ff85410421628640bf434a5fe1
Machine
JSON