The Spread

Was the forecast right for Denver on Tue Aug 4?

Denver, Colorado · daily high temperature in °C · forecasts from each model's archived runs, verified against the ECMWF IFS analysis

10 days out, 4 models put Denver's Tue Aug 4 high anywhere from 24° to 39°; by the final call the field had settled to a median of 26°. The day verified at 24° against the ECMWF IFS analysis, with 0.3 mm of precipitation — drizzle.

AIGFS landed closest, off by 0.5°. UKMO ran 3° hot.

10 days out the models said 24–39; it hit 24. AIGFS led (off 0.5°C); UKMO ran 3°C hot.
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 Denver scoreboard shows them, labelled.

Lead AIFSAIGFSECMWFGEMGFSICONUKMO Range
10d · 2026-07-25 24° 28° 29° 39° 24–39°
8d · 2026-07-27 31° 30° 30° 28° 32° 28–32°
7d · 2026-07-28 30° 30° 34° 22° 35° 22–35°
6d · 2026-07-29 22° 22° 29° 28° 30° 33° 22–33°
5d · 2026-07-30 23° 23° 32° 28° 30° 23° 32° 23–32°
4d · 2026-07-31 22° 22° 32° 24° 29° 25° 30° 22–32°
3d · 2026-08-01 24° 25° 27° 26° 32° 25° 25° 24–32°
2d · 2026-08-02 24° 25° 28° 23° 30° 27° 28° 23–30°
1d · 2026-08-03 24° 25° 28° 24° 27° 26° 26° 24–28°
0d · 2026-08-04 23° 25° 27° 26° 28° 25° 28° 23–28°
actual 24°

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 Denver — 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.