Was the forecast right for Seattle on Wed Sep 16?
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 Wed Sep 16 high anywhere from 68° to 84°; by the final call the field had settled to a median of 72°. The day verified at 74° against the SEA observations — clear.
GEM landed closest, off by 0.8°. ECMWF ran 5° cold.
What every model said, at every lead
Daily-high calls for Wed Sep 16 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 · 2026-09-01 | — | 61° | — | — | 79° | — | — | 61–79° |
| 14d · 2026-09-02 | 68° | 68° | 70° | — | 84° | — | — | 68–84° |
| 13d · 2026-09-03 | 66° | 69° | 80° | — | 72° | — | — | 66–80° |
| 12d · 2026-09-04 | 65° | 66° | 68° | — | 71° | — | — | 65–71° |
| 11d · 2026-09-05 | 71° | 73° | 73° | — | 75° | — | — | 71–75° |
| 10d · 2026-09-06 | 68° | 72° | 66° | — | 77° | — | — | 66–77° |
| 9d · 2026-09-07 | 73° | 78° | 65° | 72° | 75° | — | — | 65–78° |
| 8d · 2026-09-08 | 68° | 66° | 62° | 72° | 64° | — | — | 62–72° |
| 7d · 2026-09-09 | 72° | 74° | 78° | 68° | 82° | — | — | 68–82° |
| 6d · 2026-09-10 | 73° | 76° | 72° | 73° | 78° | 73° | 75° | 72–78° |
| 5d · 2026-09-11 | 73° | 75° | 73° | 72° | 77° | 72° | 76° | 72–77° |
| 4d · 2026-09-12 | 72° | 75° | 69° | 72° | 76° | 72° | 73° | 69–76° |
| 3d · 2026-09-13 | 71° | 75° | 69° | 71° | 76° | 71° | 73° | 69–76° |
| 2d · 2026-09-14 | 71° | 74° | 69° | 71° | 75° | 71° | 73° | 69–75° |
| 1d · 2026-09-15 | 71° | 74° | 70° | 75° | 77° | 71° | 73° | 70–77° |
| 0d · 2026-09-16 | 70° | 73° | 69° | 73° | 75° | 71° | 72° | 69–75° |
| 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.