The Spread

Was the forecast right for Seattle on Sun Aug 2?

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 2 high anywhere from 19° to 29°; by the final call the field had settled to a median of 20°. The day verified at 21° against the ECMWF IFS analysis, with 0.3 mm of precipitation — drizzle.

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

14 days out the models said 19–29; it hit 21. ECMWF led (off 0.1°C); AIGFS 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 2 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 · 2026-07-18 24° 27° 24–27°
14d · 2026-07-19 19° 23° 29° 25° 19–29°
13d · 2026-07-20 22° 31° 23° 34° 22–34°
12d · 2026-07-21 21° 24° 24° 25° 21–25°
11d · 2026-07-22 20° 23° 23° 24° 20–24°
10d · 2026-07-23 20° 24° 23° 26° 20–26°
9d · 2026-07-24 21° 21° 23° 22° 24° 21–24°
8d · 2026-07-25 21° 21° 22° 21° 24° 21–24°
7d · 2026-07-26 20° 22° 21° 20° 23° 20–23°
6d · 2026-07-27 20° 23° 21° 21° 23° 21° 21° 20–23°
5d · 2026-07-28 20° 23° 20° 20° 23° 21° 21° 20–23°
4d · 2026-07-29 20° 22° 21° 20° 22° 21° 21° 20–22°
3d · 2026-07-30 20° 21° 22° 19° 23° 20° 20° 19–23°
2d · 2026-07-31 20° 22° 21° 19° 24° 21° 20° 19–24°
1d · 2026-08-01 20° 20° 21° 21° 20° 20° 21° 20–21°
0d · 2026-08-02 20° 18° 21° 21° 20° 20° 20° 18–21°
actual 21°

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.