The Spread

Was the forecast right for Washington on Wed Aug 12?

Washington, District of Columbia · daily high temperature in °C · forecasts from each model's archived runs, verified against ERA5

13 days out, 4 models put Washington's Wed Aug 12 high anywhere from 26° to 33°; by the final call the field had settled to a median of 32°. ERA5 says the day verified at 31° with 1.5 mm of precipitation — drizzle.

ICON landed closest, off by 0.3°. GEM ran 4° hot.

13 days out the models said 26–33; it hit 31. ICON led (off 0.3°C); GEM ran 4°C hot.
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 Wed Aug 12 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 · 2026-07-28 31° 33° 31–33°
14d · 2026-07-29 30° 31° 34° 30–34°
13d · 2026-07-30 33° 26° 30° 29° 26–33°
12d · 2026-07-31 34° 32° 34° 35° 32–35°
11d · 2026-08-01 30° 27° 32° 33° 27–33°
10d · 2026-08-02 30° 28° 35° 32° 28–35°
9d · 2026-08-03 29° 30° 36° 28° 28–36°
8d · 2026-08-04 30° 29° 25° 29° 35° 25–35°
7d · 2026-08-05 31° 26° 31° 26° 24° 24–31°
6d · 2026-08-06 30° 30° 30° 33° 31° 32° 30–33°
5d · 2026-08-07 31° 31° 30° 31° 30° 30° 32° 30–32°
4d · 2026-08-08 30° 30° 33° 27° 30° 26° 30° 26–33°
3d · 2026-08-09 30° 30° 31° 27° 32° 31° 29° 27–32°
2d · 2026-08-10 31° 29° 30° 28° 32° 28° 27° 27–32°
1d · 2026-08-11 31° 30° 31° 33° 31° 30° 31° 30–33°
0d · 2026-08-12 32° 31° 32° 34° 33° 31° 32° 31–34°
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 ERA5 reanalysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.