Was the forecast right for Washington on Wed Sep 2?
Washington, District of Columbia · daily high temperature in °C · forecasts from each model's archived runs, verified against the DCA observations
13 days out, 4 models put Washington's Wed Sep 2 high anywhere from 20° to 32°; by the final call the field had settled to a median of 32°. The day verified at 33° against the DCA observations, with 8.4 mm of precipitation — drizzle.
ECMWF landed closest, off by 0.3°. GEM ran 2° cold.
What every model said, at every lead
Daily-high calls for Wed Sep 2 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 · 2026-08-20 | 28° | 20° | 25° | — | 32° | — | — | 20–32° |
| 12d · 2026-08-21 | 29° | 31° | 27° | — | 39° | — | — | 27–39° |
| 11d · 2026-08-22 | 27° | 25° | 29° | — | 31° | — | — | 25–31° |
| 10d · 2026-08-23 | 34° | 30° | 28° | — | 34° | — | — | 28–34° |
| 9d · 2026-08-24 | 35° | 31° | 37° | — | 23° | — | — | 23–37° |
| 8d · 2026-08-25 | 32° | 29° | 38° | 37° | 30° | — | — | 29–38° |
| 7d · 2026-08-26 | 37° | 36° | 40° | 37° | 40° | — | — | 36–40° |
| 6d · 2026-08-27 | 36° | 36° | 36° | 37° | 39° | 36° | — | 36–39° |
| 5d · 2026-08-28 | 36° | 35° | 38° | 37° | 40° | 37° | 33° | 33–40° |
| 4d · 2026-08-29 | 36° | 36° | 40° | 36° | 38° | 36° | 35° | 35–40° |
| 3d · 2026-08-30 | 35° | 35° | 40° | 33° | 39° | 36° | 35° | 33–40° |
| 2d · 2026-08-31 | 32° | 32° | 34° | 36° | 36° | 34° | 34° | 32–36° |
| 1d · 2026-09-01 | 30° | 33° | 31° | 29° | 37° | 30° | 35° | 29–37° |
| 0d · 2026-09-02 | 32° | 32° | 32° | 31° | 34° | 33° | 32° | 31–34° |
| actual | 33° |
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 the DCA observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.