Salt Lake City's forecast for Saturday has moved 9°F colder
77°F in the 20260915T06:00Z run, 69°F in the 20260916T18:00Z — the 3rd-largest revision of the 4 cities on the roster that moved at all. The current run's 10th-to-90th percentile spread at that hour is 4°F.
Successive cycles do not merely refresh a forecast; they leave a trail. For Saturday, September 19 at 21Z in Salt Lake City, that trail runs from 77.2°F in the 20260915T06:00Z cycle to 68.5°F in the 20260916T18:00Z — a move of -8.7°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.
| forecast revision for Saturday at 21Z api.weather.city /v1/history (nbm-qmd) |
-8.7 °F | normal 0.0 °F · 3 of 4 8 synoptic cycles |
| 10th-to-90th percentile spread at that hour api.weather.city (nbm-qmd) |
4.5 °F | normal 8.7 °F current run |
- Milepost
- 1116 · laid 2026-09-17T10:25:25Z
- 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
- 7d696fbe97415b0bf51bb051f649d3535f60b36a72ca46f849ae86d12a011d68
- Machine
- JSON