Was the forecast right for London on Sat Sep 12?
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 Sat Sep 12 high anywhere from 62° to 81°; by the final call the field had settled to a median of 72°. The day verified at 75° against the EGLL observations — cloudy.
GEM landed closest, off by 0.1°. AIGFS ran 5° cold.
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 London scoreboard shows them, labelled.
| Lead | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-08-28 | — | 64° | — | — | 62° | — | — | 62–64° |
| 14d · 2026-08-29 | 70° | 62° | 64° | — | 81° | — | — | 62–81° |
| 13d · 2026-08-30 | 72° | 68° | 66° | — | 72° | — | — | 66–72° |
| 12d · 2026-08-31 | 69° | 65° | 65° | — | 71° | — | — | 65–71° |
| 11d · 2026-09-01 | 63° | 72° | 60° | — | 70° | — | — | 60–72° |
| 10d · 2026-09-02 | 68° | 65° | 65° | — | 71° | — | — | 65–71° |
| 9d · 2026-09-03 | 66° | 61° | 66° | 62° | 73° | — | — | 61–73° |
| 8d · 2026-09-04 | 66° | 61° | 68° | 67° | 65° | — | — | 61–68° |
| 7d · 2026-09-05 | 71° | 68° | 69° | 68° | 67° | — | — | 67–71° |
| 6d · 2026-09-06 | 69° | 69° | 73° | 70° | 78° | 69° | 67° | 67–78° |
| 5d · 2026-09-07 | 70° | 70° | 73° | 68° | 75° | 72° | 70° | 68–75° |
| 4d · 2026-09-08 | 69° | 70° | 69° | 68° | 72° | 72° | 71° | 68–72° |
| 3d · 2026-09-09 | 72° | 70° | 70° | 75° | 75° | 71° | 70° | 70–75° |
| 2d · 2026-09-10 | 71° | 72° | 71° | 75° | 75° | 70° | 74° | 70–75° |
| 1d · 2026-09-11 | 71° | 71° | 74° | 76° | 76° | 71° | 74° | 71–76° |
| 0d · 2026-09-12 | 71° | 70° | 72° | 75° | 75° | 71° | 72° | 70–75° |
| 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.