The Spread

Was the forecast right for Washington on Sun Aug 16?

Washington, District of Columbia · daily high temperature in °C · forecasts from each model's archived runs, verified against the ECMWF IFS analysis

13 days out, 4 models put Washington's Sun Aug 16 high anywhere from 27° to 32°; by the final call the field had settled to a median of 26°. The ECMWF IFS analysis says the day verified at 27° with 14.0 mm of precipitation — thunderstorms.

UKMO landed closest, off by 0.6°. AIFS ran 2° cold.

13 days out the models said 27–32; it hit 27. UKMO led (off 0.6°C); AIFS ran 2°C cold.
The shareable card for this receipt — what this page looks like pasted into a thread.

What every model said, at every lead

Daily-high calls for Sun Aug 16 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 AIFSAIGFSECMWFGEMGFSICONUKMO Range
15d · 2026-08-01 30° 35° 30–35°
14d · 2026-08-02 31° 30° 37° 30–37°
13d · 2026-08-03 32° 27° 28° 28° 27–32°
12d · 2026-08-04 27° 26° 32° 21° 21–32°
11d · 2026-08-05 26° 21° 28° 31° 21–31°
10d · 2026-08-06 35° 27° 28° 31° 27–35°
9d · 2026-08-07 26° 26° 32° 33° 26–33°
8d · 2026-08-08 25° 28° 30° 29° 30° 25–30°
7d · 2026-08-09 25° 32° 32° 27° 27° 25–32°
6d · 2026-08-10 27° 26° 35° 29° 35° 31° 26–35°
5d · 2026-08-11 26° 29° 29° 29° 33° 36° 27° 26–36°
4d · 2026-08-12 31° 32° 29° 26° 36° 35° 33° 26–36°
3d · 2026-08-13 28° 29° 32° 29° 36° 34° 34° 28–36°
2d · 2026-08-14 27° 24° 31° 30° 30° 31° 34° 24–34°
1d · 2026-08-15 26° 25° 25° 28° 27° 26° 28° 25–28°
0d · 2026-08-16 25° 27° 26° 27° 26° 26° 28° 25–28°
actual 27°

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). Archive depth varies by city; receipts exist only for dates the archive watched arrive.