The Spread

Was the forecast right for London on Tue Sep 8?

London, England · daily high temperature in °F · forecasts from each model's archived runs, verified against the EGLL observations

14 days out, 4 models put London's Tue Sep 8 high anywhere from 63° to 81°; by the final call the field had settled to a median of 64°. The day verified at 64° against the EGLL observations, with 0.58 in of precipitation — showers.

AIFS landed closest, off by 0.4°. AIGFS ran 3° cold.

14 days out the models said 63–81; it hit 64. AIFS led (off 0.4°F); AIGFS ran 3°F 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 Tue Sep 8 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 London scoreboard shows them, labelled.

Lead AIFSAIGFSECMWFGEMGFSICONUKMO Range
15d · 2026-08-24 75° 76° 75–76°
14d · 2026-08-25 77° 63° 66° 81° 63–81°
13d · 2026-08-26 61° 72° 73° 65° 61–73°
12d · 2026-08-27 62° 71° 61° 67° 61–71°
11d · 2026-08-28 65° 60° 64° 67° 60–67°
10d · 2026-08-29 64° 66° 68° 70° 64–70°
9d · 2026-08-30 63° 64° 67° 68° 74° 63–74°
8d · 2026-08-31 63° 66° 72° 69° 78° 63–78°
7d · 2026-09-01 64° 64° 62° 66° 72° 62–72°
6d · 2026-09-02 67° 61° 65° 68° 66° 71° 65° 61–71°
5d · 2026-09-03 67° 60° 65° 68° 68° 66° 66° 60–68°
4d · 2026-09-04 63° 63° 65° 67° 69° 67° 66° 63–69°
3d · 2026-09-05 61° 64° 68° 67° 69° 70° 66° 61–70°
2d · 2026-09-06 62° 66° 69° 68° 69° 69° 68° 62–69°
1d · 2026-09-07 63° 61° 66° 66° 64° 66° 70° 61–70°
0d · 2026-09-08 64° 62° 63° 62° 65° 66° 64° 62–66°
actual 64°

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 London — 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 EGLL observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.