The Spread

Was the forecast right for Salt Lake City on Tue Aug 4?

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

14 days out, 4 models put Salt Lake City's Tue Aug 4 high anywhere from 37° to 40°; by the final call the field had settled to a median of 31°. The day verified at 33° against the ECMWF IFS analysis — clear.

GFS landed closest, off by 0.3°. GEM ran 3° cold.

14 days out the models said 37–40; it hit 33. GFS led (off 0.3°C); GEM ran 3°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 Tue Aug 4 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 · 2026-07-20 — 34° — — 40° — — 34–40°
14d · 2026-07-21 38° 37° 40° — 39° — — 37–40°
13d · 2026-07-22 35° 33° 42° — 38° — — 33–42°
12d · 2026-07-23 32° 32° 40° — 41° — — 32–41°
11d · 2026-07-24 32° 38° 39° — 41° — — 32–41°
10d · 2026-07-25 34° 36° 39° — 41° — — 34–41°
9d · 2026-07-26 34° 38° 37° 35° 39° — — 34–39°
8d · 2026-07-27 35° 37° 38° 36° 32° — — 32–38°
7d · 2026-07-28 35° 35° 38° 35° 34° — — 34–38°
6d · 2026-07-29 33° 32° 35° 33° 33° 37° 38° 32–38°
5d · 2026-07-30 32° 30° 36° 32° 33° 34° 34° 30–36°
4d · 2026-07-31 31° 30° 35° 31° 34° 32° 34° 30–35°
3d · 2026-08-01 32° 30° 34° 32° 33° 31° 34° 30–34°
2d · 2026-08-02 32° 30° 33° 32° 33° 31° 32° 30–33°
1d · 2026-08-03 32° 31° 33° 32° 33° 31° 31° 31–33°
0d · 2026-08-04 31° 31° 32° 30° 33° 31° 31° 30–33°
actual 33°

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 ECMWF IFS analysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.