Was the forecast right for Seattle on Tue Sep 8?
Seattle, Washington · daily high temperature in °F · forecasts from each model's archived runs, verified against the SEA observations
14 days out, 4 models put Seattle's Tue Sep 8 high anywhere from 70° to 83°; by the final call the field had settled to a median of 73°. The day verified at 74° against the SEA observations — partly cloudy.
GEM landed closest, off by 0.1°. ECMWF ran 4° cold.
What every model said, at every lead
Daily-high calls for Tue Sep 8 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 |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-08-24 | — | 86° | — | — | 70° | — | — | 70–86° |
| 14d · 2026-08-25 | 71° | 70° | 83° | — | 82° | — | — | 70–83° |
| 13d · 2026-08-26 | 64° | 73° | 74° | — | 71° | — | — | 64–74° |
| 12d · 2026-08-27 | 61° | 64° | 72° | — | 74° | — | — | 61–74° |
| 11d · 2026-08-28 | 62° | 81° | 64° | — | 66° | — | — | 62–81° |
| 10d · 2026-08-29 | 68° | 67° | 70° | — | 88° | — | — | 67–88° |
| 9d · 2026-08-30 | 66° | 58° | 65° | 63° | 76° | — | — | 58–76° |
| 8d · 2026-08-31 | 64° | 60° | 66° | 63° | 80° | — | — | 60–80° |
| 7d · 2026-09-01 | 65° | 78° | 68° | 64° | 64° | — | — | 64–78° |
| 6d · 2026-09-02 | 67° | 75° | 69° | 68° | 75° | 70° | 68° | 67–75° |
| 5d · 2026-09-03 | 68° | 73° | 67° | 67° | 74° | 69° | 70° | 67–74° |
| 4d · 2026-09-04 | 70° | 72° | 69° | 68° | 74° | 70° | 72° | 68–74° |
| 3d · 2026-09-05 | 71° | 73° | 69° | 69° | 75° | 71° | 72° | 69–75° |
| 2d · 2026-09-06 | 71° | 74° | 70° | 70° | 75° | 71° | 73° | 70–75° |
| 1d · 2026-09-07 | 70° | 74° | 70° | 75° | 76° | 70° | 74° | 70–76° |
| 0d · 2026-09-08 | 70° | 74° | 70° | 74° | 75° | 71° | 73° | 70–75° |
| actual | 74° |
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.