The Spread

Was the forecast right for Washington on Wed Aug 12?

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

13 days out, 4 models put Washington's Wed Aug 12 high anywhere from 78° to 91°; by the final call the field had settled to a median of 89°. ERA5 says the day verified at 87° with 0.06 in of precipitation — drizzle.

ICON landed closest, off by 0.6°. GEM ran 6° hot.

13 days out the models said 78–91; it hit 87. ICON led (off 0.6°F); GEM ran 6°F 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 88° 92° 88–92°
14d · 2026-07-29 85° 87° 92° 85–92°
13d · 2026-07-30 91° 78° 86° 84° 78–91°
12d · 2026-07-31 94° 89° 92° 94° 89–94°
11d · 2026-08-01 86° 81° 89° 92° 81–92°
10d · 2026-08-02 86° 82° 94° 89° 82–94°
9d · 2026-08-03 84° 86° 97° 82° 82–97°
8d · 2026-08-04 85° 85° 77° 85° 95° 77–95°
7d · 2026-08-05 88° 79° 88° 79° 75° 75–88°
6d · 2026-08-06 86° 86° 87° 91° 88° 89° 86–91°
5d · 2026-08-07 88° 87° 87° 88° 86° 86° 90° 86–90°
4d · 2026-08-08 85° 86° 91° 81° 87° 79° 86° 79–91°
3d · 2026-08-09 87° 85° 87° 81° 89° 87° 85° 81–89°
2d · 2026-08-10 87° 84° 86° 82° 89° 82° 80° 80–89°
1d · 2026-08-11 88° 86° 87° 92° 88° 87° 88° 86–92°
0d · 2026-08-12 89° 88° 90° 94° 91° 88° 89° 88–94°
actual 87°

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.