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Milepost
1113

TheForecast Post

A chronicle of American weather and climate  ·  Thursday, 17 September 2026

Minneapolis, Minnesota Revisions MILEPOST 1112

Minneapolis's forecast for Monday has moved 14°F colder

75°F in the 20260915T00:00Z run, 61°F in the 20260916T18:00Z — the largest revision of any city on the roster. 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 Monday, September 21 at 21Z in Minneapolis, that trail runs from 75.0°F in the 20260915T00:00Z cycle to 61.3°F in the 20260916T18:00Z — a move of -13.7°F across 8 runs.

The change is larger than the run's own 10th-to-90th percentile spread — the guidance did not merely narrow, it moved off its previous position.

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 21Z
api.weather.city /v1/history (nbm-qmd)
-13.7 °F normal 0.0 °F · 1 of 6
8 synoptic cycles
10th-to-90th percentile spread at that hour
api.weather.city (nbm-qmd)
11.2 °F normal 13.7 °F
current run
Milepost
1112 · laid 2026-09-17T04:25:20Z
Model
nbm-qmd · cycle 20260916T18:00Z
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
5c21edd18b90931cf710d28125a63bab6741751cbc8ac4509657d62742b0fb16
Machine
JSON