Was the forecast right for Washington on Tue Aug 4?
Washington, District of Columbia · daily high temperature in °C · forecasts from each model's archived runs, verified against the ECMWF IFS analysis
9 days out, 5 models put Washington's Tue Aug 4 high anywhere from 23° to 36°;by the final call, the day before, the field had settled to a median of 31°. The day verified at 31° against the ECMWF IFS analysis, with 1.0 mm of precipitation — drizzle.
ICON landed closest, off by 0.2°. AIGFS ran 2° cool.
What every model said, at every lead
Daily-high calls for Tue Aug 4 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 |
|---|---|---|---|---|---|---|---|---|
| 9d · 2026-07-26 | 33° | 29° | 30° | 23° | 36° | — | — | 23–36° |
| 8d · 2026-07-27 | 32° | 31° | 35° | 32° | 30° | — | — | 30–35° |
| 7d · 2026-07-28 | 32° | 29° | 31° | 32° | 32° | — | — | 29–32° |
| 6d · 2026-07-29 | 31° | 29° | 29° | 29° | 31° | 31° | 28° | 28–31° |
| 5d · 2026-07-30 | 31° | 28° | 33° | 31° | 28° | 28° | 29° | 28–33° |
| 4d · 2026-07-31 | 31° | 30° | 31° | 26° | 28° | 29° | 30° | 26–31° |
| 3d · 2026-08-01 | 28° | 29° | 29° | 29° | 27° | 27° | 30° | 27–30° |
| 2d · 2026-08-02 | 30° | 28° | 30° | 30° | 31° | 31° | 32° | 28–32° |
| 1d · 2026-08-03 | 31° | 29° | 30° | 33° | 29° | 31° | 32° | 29–33° |
| actual | 31° |
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.