Was the forecast right for Washington on Tue Sep 1?
Washington, District of Columbia · daily high temperature in °C · forecasts from each model's archived runs, verified against the DCA observations
12 days out, 4 models put Washington's Tue Sep 1 high anywhere from 24° to 37°; by the final call the field had settled to a median of 34°. The day verified at 37° against the DCA observations — drizzle.
GFS landed closest, off by 0.5°. AIGFS ran 3° cold.
What every model said, at every lead
Daily-high calls for Tue Sep 1 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 |
|---|---|---|---|---|---|---|---|---|
| 12d · 2026-08-20 | 26° | 24° | 24° | — | 37° | — | — | 24–37° |
| 11d · 2026-08-21 | 31° | 32° | 24° | — | 38° | — | — | 24–38° |
| 10d · 2026-08-22 | 27° | 31° | 28° | — | 32° | — | — | 27–32° |
| 9d · 2026-08-23 | 36° | 32° | 34° | — | 29° | — | — | 29–36° |
| 8d · 2026-08-24 | 35° | 30° | 35° | 36° | 34° | — | — | 30–36° |
| 7d · 2026-08-25 | 35° | 32° | 38° | 36° | 30° | — | — | 30–38° |
| 6d · 2026-08-26 | 36° | 35° | 38° | 36° | 33° | 36° | — | 33–38° |
| 5d · 2026-08-27 | 35° | 35° | 36° | 36° | 36° | 35° | 33° | 33–36° |
| 4d · 2026-08-28 | 33° | 34° | 36° | 37° | 34° | 35° | 30° | 30–37° |
| 3d · 2026-08-29 | 35° | 34° | 39° | 37° | 35° | 36° | 35° | 34–39° |
| 2d · 2026-08-30 | 35° | 34° | 38° | 36° | 36° | 36° | 35° | 34–38° |
| 1d · 2026-08-31 | 34° | 34° | 37° | 35° | 37° | 35° | 34° | 34–37° |
| 0d · 2026-09-01 | 34° | 34° | 35° | 34° | 36° | 34° | 35° | 34–36° |
| actual | 37° |
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.