The Spread

Was the forecast right for Washington on Sat Sep 12?

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

13 days out, 4 models put Washington's Sat Sep 12 high anywhere from 18° to 32°; by the final call the field had settled to a median of 28°. The day verified at 27° against the DCA observations — thunderstorms.

AIGFS landed closest, off by 0.1°. GFS ran 3° hot.

13 days out the models said 18–32; it hit 27. AIGFS led (off 0.1°C); GFS ran 3°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 Sat Sep 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 · 2026-08-28 29° 26° 26–29°
14d · 2026-08-29 33° 30° 31° 30–33°
13d · 2026-08-30 28° 32° 22° 18° 18–32°
12d · 2026-08-31 35° 30° 30° 26° 26–35°
11d · 2026-09-01 36° 32° 34° 32° 32–36°
10d · 2026-09-02 29° 35° 31° 30° 29–35°
9d · 2026-09-03 23° 28° 23° 28° 23–28°
8d · 2026-09-04 27° 29° 27° 24° 19° 19–29°
7d · 2026-09-05 31° 26° 26° 28° 29° 26–31°
6d · 2026-09-06 29° 29° 29° 27° 32° 29° 27–32°
5d · 2026-09-07 25° 29° 30° 28° 29° 28° 29° 25–30°
4d · 2026-09-08 23° 24° 30° 26° 30° 27° 27° 23–30°
3d · 2026-09-09 26° 27° 26° 26° 22° 26° 30° 22–30°
2d · 2026-09-10 27° 27° 29° 29° 29° 29° 26° 26–29°
1d · 2026-09-11 26° 27° 28° 29° 29° 28° 28° 26–29°
0d · 2026-09-12 27° 27° 28° 29° 30° 29° 28° 27–30°
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 DCA observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.