Was the forecast right for Washington on Thu Aug 6?
Washington, District of Columbia · daily high temperature in °C · forecasts from each model's archived runs, verified against the ECMWF IFS analysis
11 days out, 4 models put Washington's Thu Aug 6 high anywhere from 29° to 36°;by the final call, the day before, the field had settled to a median of 34°. The day verified at 34° against the ECMWF IFS analysis, with 3.3 mm of precipitation — rain.
AIFS landed closest, off by 0.0°. GEM ran 2° warm.
What every model said, at every lead
Daily-high calls for Thu Aug 6 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 |
|---|---|---|---|---|---|---|---|---|
| 11d · 2026-07-26 | 29° | 32° | 32° | — | 36° | — | — | 29–36° |
| 10d · 2026-07-27 | 30° | 32° | 34° | — | 34° | — | — | 30–34° |
| 9d · 2026-07-28 | 31° | 30° | 32° | 32° | 36° | — | — | 30–36° |
| 8d · 2026-07-29 | 31° | 31° | 30° | 33° | 30° | — | — | 30–33° |
| 7d · 2026-07-30 | 34° | 34° | 31° | 30° | 30° | — | — | 30–34° |
| 6d · 2026-07-31 | 34° | 34° | 31° | 32° | 34° | 32° | 32° | 31–34° |
| 5d · 2026-08-01 | 33° | 34° | 31° | 30° | 36° | 33° | 34° | 30–36° |
| 4d · 2026-08-02 | 33° | 34° | 32° | 33° | 35° | 34° | 34° | 32–35° |
| 3d · 2026-08-03 | 33° | 33° | 33° | 32° | 35° | 33° | 33° | 32–35° |
| 2d · 2026-08-04 | 34° | 34° | 34° | 34° | 35° | 33° | 35° | 33–35° |
| 1d · 2026-08-05 | 34° | 34° | 33° | 36° | 33° | 34° | 34° | 33–36° |
| actual | 34° |
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 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.