The Spread

Was the forecast right for Seattle on Mon Sep 7?

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

14 days out, 4 models put Seattle's Mon Sep 7 high anywhere from 22° to 31°; by the final call the field had settled to a median of 20°. The day verified at 21° against the SEA observations — showers.

UKMO landed closest, off by 0.2°. AIGFS ran 3° cold.

14 days out the models said 22–31; it hit 21. UKMO led (off 0.2°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 Mon Sep 7 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 · 2026-08-23 30° 34° 30–34°
14d · 2026-08-24 22° 28° 31° 22° 22–31°
13d · 2026-08-25 25° 30° 28° 27° 25–30°
12d · 2026-08-26 19° 23° 21° 21° 19–23°
11d · 2026-08-27 16° 23° 18° 24° 16–24°
10d · 2026-08-28 16° 23° 19° 21° 16–23°
9d · 2026-08-29 19° 22° 21° 16° 31° 16–31°
8d · 2026-08-30 20° 15° 18° 17° 30° 15–30°
7d · 2026-08-31 18° 19° 21° 19° 27° 18–27°
6d · 2026-09-01 17° 25° 20° 19° 29° 24° 20° 17–29°
5d · 2026-09-02 19° 24° 22° 19° 27° 21° 17° 17–27°
4d · 2026-09-03 18° 22° 21° 20° 26° 21° 22° 18–26°
3d · 2026-09-04 19° 18° 19° 20° 21° 20° 22° 18–22°
2d · 2026-09-05 20° 18° 19° 16° 20° 20° 21° 16–21°
1d · 2026-09-06 20° 19° 20° 20° 21° 20° 21° 19–21°
0d · 2026-09-07 19° 18° 20° 22° 22° 20° 21° 18–22°
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 SEA observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.