Was the forecast right for Washington on Sun Aug 9?
Washington, District of Columbia · daily high temperature in °F · forecasts from each model's archived runs, verified against ERA5
13 days out, 4 models put Washington's Sun Aug 9 high anywhere from 80° to 92°; by the final call the field had settled to a median of 94°. ERA5 says the day verified at 92° — partly cloudy.
ICON landed closest, off by 1.2°. GEM ran 5° hot.
What every model said, at every lead
Daily-high calls for Sun Aug 9 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 Washington scoreboard shows them, labelled.
| Lead | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 13d · 2026-07-27 | 92° | 80° | 89° | — | 91° | — | — | 80–92° |
| 12d · 2026-07-28 | 89° | 92° | 88° | — | 100° | — | — | 88–100° |
| 11d · 2026-07-29 | 88° | 90° | 91° | — | 94° | — | — | 88–94° |
| 10d · 2026-07-30 | 87° | 94° | 93° | — | 94° | — | — | 87–94° |
| 9d · 2026-07-31 | 91° | 94° | 90° | — | 98° | — | — | 90–98° |
| 8d · 2026-08-01 | 91° | 96° | 92° | 94° | 96° | — | — | 91–96° |
| 7d · 2026-08-02 | 92° | 89° | 89° | 92° | 99° | — | — | 89–99° |
| 6d · 2026-08-03 | 92° | 92° | 87° | 93° | 98° | 92° | — | 87–98° |
| 5d · 2026-08-04 | 92° | 91° | 88° | 84° | 96° | 96° | 91° | 84–96° |
| 4d · 2026-08-05 | 93° | 92° | 90° | 84° | 95° | 93° | 91° | 84–95° |
| 3d · 2026-08-06 | 93° | 92° | 89° | 88° | 94° | 93° | 91° | 88–94° |
| 2d · 2026-08-07 | 92° | 90° | 93° | 91° | 96° | 93° | 93° | 90–96° |
| 1d · 2026-08-08 | 94° | 93° | 94° | 96° | 98° | 94° | 94° | 93–98° |
| 0d · 2026-08-09 | 95° | 94° | 93° | 97° | 96° | 93° | 94° | 93–97° |
| actual | 92° |
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 Washington — 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 ERA5 reanalysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.