The Spread

Was the forecast right for London on Sat Sep 5?

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

14 days out, 4 models put London's Sat Sep 5 high anywhere from 17° to 25°; by the final call the field had settled to a median of 22°. The day verified at 23° against the EGLL observations — cloudy.

GFS landed closest, off by 0.3°. AIGFS ran 2° cold.

14 days out the models said 17–25; it hit 23. GFS led (off 0.3°C); AIGFS ran 2°C 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 Sat Sep 5 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
14d · 2026-08-22 25° 17° 21° 21° 17–25°
13d · 2026-08-23 24° 23° 25° 19° 19–25°
12d · 2026-08-24 23° 20° 20° 19° 19–23°
11d · 2026-08-25 19° 19° 27° 19° 19–27°
10d · 2026-08-26 26° 18° 20° 25° 18–26°
9d · 2026-08-27 21° 20° 23° 26° 19° 19–26°
8d · 2026-08-28 22° 22° 18° 26° 21° 18–26°
7d · 2026-08-29 23° 21° 17° 22° 25° 17–25°
6d · 2026-08-30 23° 21° 21° 18° 21° 20° 21° 18–23°
5d · 2026-08-31 22° 22° 21° 23° 22° 22° 22° 21–23°
4d · 2026-09-01 22° 21° 20° 22° 21° 21° 21° 20–22°
3d · 2026-09-02 22° 21° 22° 23° 23° 22° 22° 21–23°
2d · 2026-09-03 21° 21° 22° 23° 23° 21° 21° 21–23°
1d · 2026-09-04 21° 21° 22° 22° 22° 22° 22° 21–22°
0d · 2026-09-05 22° 21° 22° 22° 23° 22° 21° 21–23°
actual 23°

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.