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 1042

Nashville's forecast for Saturday has moved 11°F colder

70°F in the 20260908T12:00Z run, 60°F in the 20260910T06:00Z — 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 Saturday, September 19 at 12Z in Nashville, that trail runs from 70.5°F in the 20260908T12:00Z cycle to 59.6°F in the 20260910T06:00Z — a move of -10.9°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 Saturday at 12Z
api.weather.city /v1/history (nbm-qmd)
-10.9 °F normal 0.0 °F · 2 of 7
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
20.8 °F normal 10.9 °F
current run
Milepost
1042 · laid 2026-09-10T16:16:45Z
Model
nbm-qmd · cycle 20260910T06:00Z
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
e95d8569a05d4909a925e336854c61fbc7829b92da45c6716976bc969afef714
Machine
JSON