The Spread

Was the forecast right for Seattle on Thu Aug 13?

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 Thu Aug 13 high anywhere from 19° to 25°; by the final call the field had settled to a median of 26°. ERA5 says the day verified at 26° — cloudy.

ECMWF landed closest, off by 0.2°. AIGFS ran 3° hot.

14 days out the models said 19–25; it hit 26. ECMWF led (off 0.2°C); AIGFS 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 Thu Aug 13 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 · 2026-07-29 29° 29° 29–29°
14d · 2026-07-30 19° 25° 25° 23° 19–25°
13d · 2026-07-31 27° 22° 25° 24° 22–27°
12d · 2026-08-01 23° 32° 27° 29° 23–32°
11d · 2026-08-02 22° 32° 23° 26° 22–32°
10d · 2026-08-03 21° 26° 24° 28° 21–28°
9d · 2026-08-04 22° 31° 30° 26° 31° 22–31°
8d · 2026-08-05 22° 24° 26° 22° 22° 22–26°
7d · 2026-08-06 27° 23° 28° 24° 25° 23–28°
6d · 2026-08-07 26° 24° 28° 25° 25° 22° 26° 22–28°
5d · 2026-08-08 25° 23° 27° 24° 27° 25° 26° 23–27°
4d · 2026-08-09 25° 28° 26° 24° 28° 26° 26° 24–28°
3d · 2026-08-10 25° 28° 26° 24° 29° 25° 26° 24–29°
2d · 2026-08-11 25° 29° 26° 23° 28° 25° 27° 23–29°
1d · 2026-08-12 25° 29° 27° 28° 27° 25° 28° 25–29°
0d · 2026-08-13 25° 29° 27° 26° 25° 25° 27° 25–29°
actual 26°

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.