The Spread

Was the forecast right for Seattle on Sun Aug 16?

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

14 days out, 4 models put Seattle's Sun Aug 16 high anywhere from 24° to 28°; by the final call the field had settled to a median of 24°. The ECMWF IFS analysis says the day verified at 24° — cloudy.

ECMWF landed closest, off by 0.1°. AIFS ran 3° cold.

14 days out the models said 24–28; it hit 24. ECMWF led (off 0.1°C); AIFS 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 Sun Aug 16 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 · 2026-08-01 16° 27° 16–27°
14d · 2026-08-02 26° 26° 24° 28° 24–28°
13d · 2026-08-03 22° 26° 26° 24° 22–26°
12d · 2026-08-04 25° 22° 33° 29° 22–33°
11d · 2026-08-05 28° 20° 28° 21° 20–28°
10d · 2026-08-06 22° 26° 23° 24° 22–26°
9d · 2026-08-07 24° 24° 28° 26° 30° 24–30°
8d · 2026-08-08 22° 21° 25° 25° 33° 21–33°
7d · 2026-08-09 24° 27° 27° 26° 29° 24–29°
6d · 2026-08-10 22° 28° 27° 24° 29° 25° 28° 22–29°
5d · 2026-08-11 23° 27° 26° 24° 28° 26° 26° 23–28°
4d · 2026-08-12 23° 25° 26° 25° 30° 25° 27° 23–30°
3d · 2026-08-13 22° 25° 26° 23° 29° 23° 26° 22–29°
2d · 2026-08-14 21° 24° 26° 23° 29° 24° 25° 21–29°
1d · 2026-08-15 20° 24° 26° 25° 24° 23° 25° 20–26°
0d · 2026-08-16 21° 24° 24° 24° 22° 22° 24° 21–24°
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 the ECMWF IFS analysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.