Was the forecast right for Seattle on Mon Jul 27?
Seattle, Washington · daily high temperature in °F · forecasts from each model's archived runs, verified against the ECMWF IFS analysis
10 days out, 4 models put Seattle's Mon Jul 27 high anywhere from 66° to 83°;by the final call, the day before, the field had settled to a median of 77°. The day verified at 78° against the ECMWF IFS analysis — cloudy.
GEM landed closest, off by 0.5°. ICON ran 4° cool.
What every model said, at every lead
Daily-high calls for Mon Jul 27 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 |
|---|---|---|---|---|---|---|---|---|
| 10d · 2026-07-17 | 68° | 77° | 66° | — | 83° | — | — | 66–83° |
| 9d · 2026-07-18 | 62° | 70° | 77° | 72° | 78° | — | — | 62–78° |
| 8d · 2026-07-19 | 64° | 72° | 79° | 71° | 79° | — | — | 64–79° |
| 7d · 2026-07-20 | 69° | 72° | 74° | 73° | 77° | 73° | — | 69–77° |
| 6d · 2026-07-21 | 64° | 76° | 68° | 65° | 78° | 75° | 78° | 64–78° |
| 5d · 2026-07-22 | 74° | 75° | 78° | 74° | 80° | 73° | 74° | 73–80° |
| 4d · 2026-07-23 | 74° | 76° | 78° | 75° | 80° | 78° | 75° | 74–80° |
| 3d · 2026-07-24 | 75° | 78° | 76° | 74° | 83° | 74° | 77° | 74–83° |
| 2d · 2026-07-25 | 74° | 77° | 76° | 77° | 78° | 77° | 77° | 74–78° |
| 1d · 2026-07-26 | 76° | 77° | 77° | 78° | 76° | 75° | 77° | 75–78° |
| 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). 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.