Was the forecast right for Seattle on Mon Sep 7?
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 Mon Sep 7 high anywhere from 80° to 100°;by the final call, the day before, the field had settled to a median of 68°. The day verified at 70° against the SEA observations — showers.
GEM landed closest, off by 1.1°. AIGFS ran 4° cool.
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 | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-08-23 | — | 92° | — | — | 78° | — | — | 78–92° |
| 14d · 2026-08-24 | 80° | 80° | 87° | — | 100° | — | — | 80–100° |
| 13d · 2026-08-25 | 81° | 79° | 82° | — | 84° | — | — | 79–84° |
| 12d · 2026-08-26 | 72° | 69° | 70° | — | 87° | — | — | 69–87° |
| 11d · 2026-08-27 | 71° | 65° | 65° | — | 82° | — | — | 65–82° |
| 10d · 2026-08-28 | 60° | 71° | 67° | — | 81° | — | — | 60–81° |
| 9d · 2026-08-29 | 67° | 71° | 70° | 66° | 82° | — | — | 66–82° |
| 8d · 2026-08-30 | 67° | 62° | 65° | 67° | 74° | — | — | 62–74° |
| 7d · 2026-08-31 | 66° | 73° | 69° | 74° | 73° | 73° | — | 66–74° |
| 6d · 2026-09-01 | 66° | 75° | 68° | 68° | 81° | 74° | 68° | 66–81° |
| 5d · 2026-09-02 | 66° | 70° | 73° | 69° | 77° | 71° | 63° | 63–77° |
| 4d · 2026-09-03 | 66° | 73° | 68° | 69° | 77° | 69° | 72° | 66–77° |
| 3d · 2026-09-04 | 67° | 64° | 68° | 66° | 65° | 69° | 71° | 64–71° |
| 2d · 2026-09-05 | 68° | 65° | 66° | 70° | 72° | 67° | 70° | 65–72° |
| 1d · 2026-09-06 | 68° | 66° | 67° | 71° | 72° | 67° | 69° | 66–72° |
| actual | 70° |
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.