The Spread

Was the forecast right for London on Mon Sep 7?

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 Mon Sep 7 high anywhere from 70° to 76°; by the final call the field had settled to a median of 75°. The day verified at 75° against the EGLL observations — cloudy.

GFS landed closest, off by 0.1°. AIGFS ran 2° cold.

14 days out the models said 70–76; it hit 75. GFS led (off 0.1°F); AIGFS ran 2°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 Mon Sep 7 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 · 2026-08-23 64° 74° 64–74°
14d · 2026-08-24 70° 76° 71° 71° 70–76°
13d · 2026-08-25 74° 64° 66° 72° 64–74°
12d · 2026-08-26 67° 63° 71° 70° 63–71°
11d · 2026-08-27 64° 71° 64° 60° 60–71°
10d · 2026-08-28 66° 62° 67° 69° 62–69°
9d · 2026-08-29 65° 74° 69° 80° 67° 65–80°
8d · 2026-08-30 68° 78° 71° 66° 81° 66–81°
7d · 2026-08-31 72° 76° 75° 77° 79° 72–79°
6d · 2026-09-01 73° 73° 67° 71° 83° 72° 68° 67–83°
5d · 2026-09-02 74° 77° 74° 78° 72° 72° 72° 72–78°
4d · 2026-09-03 71° 73° 74° 74° 74° 74° 70° 70–74°
3d · 2026-09-04 71° 72° 73° 75° 76° 71° 71° 71–76°
2d · 2026-09-05 72° 72° 73° 75° 75° 70° 70° 70–75°
1d · 2026-09-06 72° 73° 74° 75° 74° 72° 74° 72–75°
0d · 2026-09-07 74° 73° 76° 77° 75° 75° 75° 73–77°
actual 75°

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.