The Spread

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 ERA5

10 days out, 4 models put Washington's Thu Aug 6 high anywhere from 31° to 37°; by the final call the field had settled to a median of 34°. ERA5 says the day verified at 34° with 3.3 mm of precipitation — rain.

ICON landed closest, off by 0.2°. GEM ran 2° hot.

10 days out the models said 31–37; it hit 34. ICON led (off 0.2°C); GEM ran 2°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 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 AIFSAIGFSECMWFGEMGFSICONUKMO Range
10d · 2026-07-27 31° 32° 32° — 37° — — 31–37°
9d · 2026-07-28 32° 32° 29° — 27° — — 27–32°
8d · 2026-07-29 33° 29° 30° 31° 32° — — 29–33°
7d · 2026-07-30 31° 33° 31° 32° 34° — — 31–34°
6d · 2026-07-31 32° 35° 33° 34° 29° 33° — 29–35°
5d · 2026-08-01 33° 35° 31° 32° 36° 33° 34° 31–36°
4d · 2026-08-02 33° 34° 35° 32° 34° 34° 34° 32–35°
3d · 2026-08-03 33° 33° 32° 33° 36° 33° 34° 32–36°
2d · 2026-08-04 34° 33° 32° 33° 36° 34° 34° 32–36°
1d · 2026-08-05 34° 34° 34° 36° 33° 34° 34° 33–36°
0d · 2026-08-06 34° 34° 34° 36° 34° 33° 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 ERA5 reanalysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.