Was the forecast right for Seattle on Mon Aug 17?
Seattle, Washington · daily high temperature in °F · forecasts from each model's archived runs, verified against the ECMWF IFS analysis
14 days out, 4 models put Seattle's Mon Aug 17 high anywhere from 68° to 75°; by the final call the field had settled to a median of 77°. The ECMWF IFS analysis says the day verified at 78° — cloudy.
ECMWF landed closest, off by 0.3°. AIFS ran 4° cold.
What every model said, at every lead
Daily-high calls for Mon Aug 17 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 · 2026-08-02 | — | 65° | — | — | 81° | — | — | 65–81° |
| 14d · 2026-08-03 | 68° | 68° | 75° | — | 75° | — | — | 68–75° |
| 13d · 2026-08-04 | 71° | 68° | 89° | — | 78° | — | — | 68–89° |
| 12d · 2026-08-05 | 80° | 70° | 82° | — | 62° | — | — | 62–82° |
| 11d · 2026-08-06 | 70° | 69° | 72° | — | 68° | — | — | 68–72° |
| 10d · 2026-08-07 | 75° | 69° | 88° | — | 87° | — | — | 69–88° |
| 9d · 2026-08-08 | 68° | 60° | 73° | 75° | 89° | — | — | 60–89° |
| 8d · 2026-08-09 | 71° | 80° | 76° | 71° | 82° | — | — | 71–82° |
| 7d · 2026-08-10 | 70° | 82° | 82° | 78° | 80° | — | — | 70–82° |
| 6d · 2026-08-11 | 72° | 80° | 80° | 74° | 86° | 76° | 79° | 72–86° |
| 5d · 2026-08-12 | 75° | 76° | 78° | 75° | 75° | 77° | 82° | 75–82° |
| 4d · 2026-08-13 | 73° | 75° | 80° | 77° | 83° | 75° | 81° | 73–83° |
| 3d · 2026-08-14 | 73° | 79° | 78° | 73° | 86° | 76° | 78° | 73–86° |
| 2d · 2026-08-15 | 72° | 81° | 78° | 72° | 82° | 76° | 80° | 72–82° |
| 1d · 2026-08-16 | 73° | 80° | 78° | 78° | 79° | 76° | 80° | 73–80° |
| 0d · 2026-08-17 | 73° | 80° | 77° | 78° | 75° | 75° | 79° | 73–80° |
| actual | 78° |
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 ECMWF IFS analysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.