Was the forecast right for Washington on Sun Aug 30?
Washington, District of Columbia · daily high temperature in °C · forecasts from each model's archived runs, verified against the DCA observations
10 days out, 4 models put Washington's Sun Aug 30 high anywhere from 24° to 35°; by the final call the field had settled to a median of 32°. The day verified at 32° against the DCA observations, with 4.6 mm of precipitation — drizzle.
UKMO landed closest, off by 0.1°. GFS ran 3° hot.
What every model said, at every lead
Daily-high calls for Sun Aug 30 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 |
|---|---|---|---|---|---|---|---|---|
| 10d · 2026-08-20 | 29° | 24° | 31° | — | 35° | — | — | 24–35° |
| 9d · 2026-08-21 | 27° | 29° | 31° | — | 32° | — | — | 27–32° |
| 8d · 2026-08-22 | 26° | 25° | 29° | 27° | 31° | — | — | 25–31° |
| 7d · 2026-08-23 | 30° | 26° | 33° | 32° | 33° | — | — | 26–33° |
| 6d · 2026-08-24 | 30° | 32° | 31° | 31° | 35° | 33° | — | 30–35° |
| 5d · 2026-08-25 | 31° | 29° | 32° | 30° | 33° | 32° | 32° | 29–33° |
| 4d · 2026-08-26 | 31° | 30° | 32° | 33° | 33° | 31° | 33° | 30–33° |
| 3d · 2026-08-27 | 31° | 32° | 31° | 33° | 34° | 32° | 32° | 31–34° |
| 2d · 2026-08-28 | 31° | 32° | 32° | 33° | 34° | 33° | 31° | 31–34° |
| 1d · 2026-08-29 | 31° | 33° | 33° | 32° | 34° | 32° | 31° | 31–34° |
| 0d · 2026-08-30 | 31° | 32° | 33° | 32° | 35° | 32° | 32° | 31–35° |
| actual | 32° |
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.