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Milepost
1108

TheForecast Post

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

Salt Lake City, Utah Revisions MILEPOST 1051

Salt Lake City's forecast for Sunday has moved 14°F warmer

65°F in the 20260909T06:00Z run, 79°F in the 20260911T00:00Z — the largest revision of any city on the roster. The current run's 10th-to-90th percentile spread at that hour is 18°F.

Successive cycles do not merely refresh a forecast; they leave a trail. For Sunday, September 13 at 18Z in Salt Lake City, that trail runs from 65.4°F in the 20260909T06:00Z cycle to 78.9°F in the 20260911T00:00Z — a move of +13.5°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)
13.5 °F normal 0.0 °F · 1 of 8
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
18.1 °F normal 13.5 °F
current run
Milepost
1051 · laid 2026-09-11T10:25:10Z
Model
nbm-qmd · cycle 20260911T00:00Z
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
4dc787e6ecd04217a76e237909c7a2eb8fee595241036700dc20356b47cac9c4
Machine
JSON