Was the forecast right for Seattle on Mon Aug 31?
Seattle, Washington · daily high temperature in °C · forecasts from each model's archived runs, verified against the SEA observations
8 days out, 5 models put Seattle's Mon Aug 31 high anywhere from 15° to 26°;by the final call, the day before, the field had settled to a median of 24°. The day verified at 24° against the SEA observations — cloudy.
AIGFS landed closest, off by 0.0°. ICON ran 3° cool.
What every model said, at every lead
Daily-high calls for Mon Aug 31 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 | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 8d · 2026-08-23 | 18° | 25° | 23° | 15° | 26° | — | — | 15–26° |
| 7d · 2026-08-24 | 21° | 19° | 17° | 20° | 23° | 29° | — | 17–29° |
| 6d · 2026-08-25 | 21° | 19° | 23° | 20° | 15° | 22° | 24° | 15–24° |
| 5d · 2026-08-26 | 22° | 23° | 23° | 22° | 25° | 23° | 23° | 22–25° |
| 4d · 2026-08-27 | 22° | 24° | 21° | 22° | 24° | 21° | 24° | 21–24° |
| 3d · 2026-08-28 | 22° | 24° | 22° | 22° | 25° | 21° | 24° | 21–25° |
| 2d · 2026-08-29 | 22° | 25° | 21° | 25° | 24° | 22° | 24° | 21–25° |
| 1d · 2026-08-30 | 22° | 24° | 22° | 25° | 25° | 21° | 24° | 21–25° |
| 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 SEA observations. The actual values are the ones in hand when this receipt was settled, usually 2 days after the date; a correction published after that is not carried into it. Archive depth varies by city; receipts exist only for dates the archive watched arrive.