The Spread

Was the forecast right for Salt Lake City on Wed Sep 9?

Salt Lake City, Utah · daily high temperature in °C · forecasts from each model's archived runs, verified against the SLC observations

14 days out, 4 models put Salt Lake City's Wed Sep 9 high anywhere from 19° to 31°; by the final call the field had settled to a median of 28°. The day verified at 29° against the SLC observations — partly cloudy.

GEM landed closest, off by 0.9°. AIGFS ran 2° cold.

14 days out the models said 19–31; it hit 29. GEM led (off 0.9°C); AIGFS ran 2°C cold.
The shareable card for this receipt — what this page looks like pasted into a thread.

What every model said, at every lead

Daily-high calls for Wed Sep 9 as each model's runs approached it — the last archived run per day. NBM and The Spread's own blend are consensus products and stay out of these ranges and rankings; the Salt Lake City scoreboard shows them, labelled.

Lead AIFSAIGFSECMWFGEMGFSICONUKMO Range
15d · 2026-08-25 30° 30° 30–30°
14d · 2026-08-26 19° 29° 31° 28° 19–31°
13d · 2026-08-27 31° 32° 33° 28° 28–33°
12d · 2026-08-28 32° 29° 30° 29° 29–32°
11d · 2026-08-29 24° 20° 28° 34° 20–34°
10d · 2026-08-30 33° 28° 22° 32° 22–33°
9d · 2026-08-31 27° 22° 25° 17° 33° 17–33°
8d · 2026-09-01 28° 24° 30° 18° 29° 18–30°
7d · 2026-09-02 29° 29° 30° 30° 33° 29–33°
6d · 2026-09-03 29° 29° 32° 25° 27° 26° 23° 23–32°
5d · 2026-09-04 29° 27° 30° 28° 32° 30° 30° 27–32°
4d · 2026-09-05 29° 27° 31° 28° 29° 28° 29° 27–31°
3d · 2026-09-06 28° 27° 29° 28° 30° 28° 28° 27–30°
2d · 2026-09-07 28° 27° 29° 27° 29° 30° 28° 27–30°
1d · 2026-09-08 28° 26° 29° 28° 28° 28° 28° 26–29°
0d · 2026-09-09 28° 27° 28° 28° 28° 28° 28° 27–28°
actual 29°

Read it honestly

This is one date, not a league table. A model can win a day it deserved to lose; rankings only mean something over a window. For that, see which model has been most accurate in Salt Lake City — or every city The Spread scores.

Forecasts are what each model's archived runs said at the time, captured at The Spread's sweep times — never reconstructed after the fact. Truth is the SLC observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.