Was the forecast right for Seattle on Mon Aug 31?
Seattle, Washington · daily high temperature in °F · 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 67° to 73°; by the final call the field had settled to a median of 74°. The day verified at 76° against the SEA observations — cloudy.
GEM landed closest, off by 0.1°. AIFS ran 4° cold.
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 | 70° | 70° | 73° | 67° | 71° | — | — | 67–73° |
| 7d · 2026-08-24 | 71° | 74° | 62° | 71° | 63° | — | — | 62–74° |
| 6d · 2026-08-25 | 67° | 75° | 74° | 65° | 74° | 77° | 75° | 65–77° |
| 5d · 2026-08-26 | 71° | 72° | 73° | 72° | 63° | 72° | 74° | 63–74° |
| 4d · 2026-08-27 | 71° | 77° | 69° | 71° | 77° | 68° | 74° | 68–77° |
| 3d · 2026-08-28 | 72° | 76° | 72° | 71° | 76° | 71° | 76° | 71–76° |
| 2d · 2026-08-29 | 72° | 77° | 71° | 70° | 76° | 71° | 74° | 70–77° |
| 1d · 2026-08-30 | 72° | 76° | 72° | 77° | 76° | 70° | 75° | 70–77° |
| 0d · 2026-08-31 | 72° | 74° | 73° | 76° | 77° | 72° | 74° | 72–77° |
| actual | 76° |
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.