Was the forecast right for Seattle on Sun Aug 16?
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 Sun Aug 16 high anywhere from 75° to 89°;by the final call, the day before, the field had settled to a median of 75°. The day verified at 75° against the ECMWF IFS analysis — cloudy.
AIGFS landed closest, off by 0.1°. AIFS ran 7° cool.
What every model said, at every lead
Daily-high calls for Sun Aug 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 · 2026-08-01 | — | 72° | — | — | 83° | — | — | 72–83° |
| 14d · 2026-08-02 | 75° | 89° | 76° | — | 79° | — | — | 75–89° |
| 13d · 2026-08-03 | 73° | 80° | 79° | — | 76° | — | — | 73–80° |
| 12d · 2026-08-04 | 77° | 77° | 91° | — | 78° | — | — | 77–91° |
| 11d · 2026-08-05 | 76° | 68° | 83° | — | 80° | — | — | 68–83° |
| 10d · 2026-08-06 | 68° | 85° | 73° | — | 90° | — | — | 68–90° |
| 9d · 2026-08-07 | 72° | 76° | 82° | 80° | 88° | — | — | 72–88° |
| 8d · 2026-08-08 | 74° | 75° | 77° | 75° | 85° | — | — | 74–85° |
| 7d · 2026-08-09 | 74° | 80° | 80° | 78° | 82° | 76° | — | 74–82° |
| 6d · 2026-08-10 | 73° | 81° | 81° | 75° | 82° | 76° | 82° | 73–82° |
| 5d · 2026-08-11 | 72° | 80° | 80° | 77° | 86° | 76° | 79° | 72–86° |
| 4d · 2026-08-12 | 73° | 76° | 79° | 77° | 84° | 75° | 80° | 73–84° |
| 3d · 2026-08-13 | 72° | 76° | 78° | 74° | 84° | 75° | 79° | 72–84° |
| 2d · 2026-08-14 | 69° | 77° | 79° | 75° | 78° | 75° | 77° | 69–79° |
| 1d · 2026-08-15 | 68° | 75° | 77° | 76° | 72° | 72° | 78° | 68–78° |
| actual | 75° |
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). 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.