Was the forecast right for Seattle on Tue Aug 4?
Seattle, Washington · daily high temperature in °C · forecasts from each model's archived runs, verified against the ECMWF IFS analysis
14 days out, 4 models put Seattle's Tue Aug 4 high anywhere from 22° to 30°; by the final call the field had settled to a median of 26°. The day verified at 26° against the ECMWF IFS analysis — clear.
AIFS landed closest, off by 0.1°. AIGFS ran 3° hot.
What every model said, at every lead
Daily-high calls for Tue Aug 4 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 · 2026-07-20 | — | 35° | — | — | 29° | — | — | 29–35° |
| 14d · 2026-07-21 | 25° | 22° | 30° | — | 27° | — | — | 22–30° |
| 13d · 2026-07-22 | 23° | 22° | 25° | — | 26° | — | — | 22–26° |
| 12d · 2026-07-23 | 22° | 31° | 26° | — | 28° | — | — | 22–31° |
| 11d · 2026-07-24 | 27° | 21° | 28° | — | 20° | — | — | 20–28° |
| 10d · 2026-07-25 | 27° | 30° | 28° | — | 29° | — | — | 27–30° |
| 9d · 2026-07-26 | 25° | 28° | 27° | 24° | 27° | — | — | 24–28° |
| 8d · 2026-07-27 | 27° | 33° | 25° | 25° | 28° | — | — | 25–33° |
| 7d · 2026-07-28 | 28° | 31° | 25° | 25° | 28° | — | — | 25–31° |
| 6d · 2026-07-29 | 27° | 30° | 28° | 24° | 28° | 27° | 28° | 24–30° |
| 5d · 2026-07-30 | 27° | 29° | 28° | 25° | 28° | 27° | 28° | 25–29° |
| 4d · 2026-07-31 | 27° | 30° | 28° | 25° | 28° | 27° | 28° | 25–30° |
| 3d · 2026-08-01 | 27° | 30° | 28° | 25° | 29° | 27° | 28° | 25–30° |
| 2d · 2026-08-02 | 27° | 30° | 29° | 25° | 28° | 26° | 28° | 25–30° |
| 1d · 2026-08-03 | 27° | 30° | 28° | 27° | 27° | 26° | 28° | 26–30° |
| 0d · 2026-08-04 | 26° | 29° | 27° | 25° | 25° | 25° | 26° | 25–29° |
| actual | 26° |
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.