The Spread

Was the forecast right for Seattle on Thu Aug 27?

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

4 days out, 7 models put Seattle's Thu Aug 27 high anywhere from 20° to 25°; by the final call the field had settled to a median of 22°. The day verified at 23° against the SEA observations — drizzle.

GFS landed closest, off by 0.6°. AIFS ran 2° cold.

4 days out the models said 20–25; it hit 23. GFS led (off 0.6°C); AIFS ran 2°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 Thu Aug 27 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
4d · 2026-08-23 21° 23° 23° 22° 25° 20° 23° 20–25°
3d · 2026-08-24 21° 22° 23° 22° 24° 24° 23° 21–24°
2d · 2026-08-25 20° 23° 23° 22° 26° 22° 23° 20–26°
1d · 2026-08-26 21° 22° 22° 23° 23° 21° 22° 21–23°
0d · 2026-08-27 21° 22° 22° 23° 23° 22° 22° 21–23°
actual 23°

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.