The Spread

Was the forecast right for Seattle on Mon Aug 10?

Seattle, Washington · daily high temperature in °C · forecasts from each model's archived runs, verified against ERA5

14 days out, 4 models put Seattle's Mon Aug 10 high anywhere from 25° to 26°; by the final call the field had settled to a median of 23°. ERA5 says the day verified at 24° — cloudy.

GEM landed closest, off by 0.2°. GFS ran 3° cold.

14 days out the models said 25–26; it hit 24. GEM led (off 0.2°C); GFS 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 Mon Aug 10 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 Seattle scoreboard shows them, labelled.

Lead AIFSAIGFSECMWFGEMGFSICONUKMO Range
15d · 2026-07-26 27° 27° 27–27°
14d · 2026-07-27 26° 26° 26° 25° 25–26°
13d · 2026-07-28 20° 19° 21° 22° 19–22°
12d · 2026-07-29 27° 24° 27° 32° 24–32°
11d · 2026-07-30 22° 37° 28° 27° 22–37°
10d · 2026-07-31 24° 24° 26° 27° 24–27°
9d · 2026-08-01 25° 28° 24° 25° 24° 24–28°
8d · 2026-08-02 22° 27° 22° 24° 26° 22–27°
7d · 2026-08-03 26° 29° 25° 24° 28° 24–29°
6d · 2026-08-04 26° 28° 25° 24° 29° 25° 26° 24–29°
5d · 2026-08-05 23° 29° 25° 24° 30° 24° 25° 23–30°
4d · 2026-08-06 24° 29° 26° 24° 29° 25° 25° 24–29°
3d · 2026-08-07 23° 27° 26° 23° 28° 24° 25° 23–28°
2d · 2026-08-08 23° 26° 25° 23° 28° 24° 25° 23–28°
1d · 2026-08-09 23° 26° 24° 25° 24° 24° 25° 23–26°
0d · 2026-08-10 22° 24° 24° 23° 21° 23° 25° 21–25°
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 Seattle — 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 ERA5 reanalysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.