Was the forecast right for London on Sun Sep 6?
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 Sun Sep 6 high anywhere from 67° to 73°; by the final call the field had settled to a median of 78°. The day verified at 81° against the EGLL observations — drizzle.
GFS landed closest, off by 1.6°. AIGFS ran 4° cold.
What every model said, at every lead
Daily-high calls for Sun Sep 6 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 · 2026-08-22 | — | 65° | — | — | 70° | — | — | 65–70° |
| 14d · 2026-08-23 | 73° | 67° | 71° | — | 72° | — | — | 67–73° |
| 13d · 2026-08-24 | 68° | 71° | 69° | — | 67° | — | — | 67–71° |
| 12d · 2026-08-25 | 68° | 66° | 65° | — | 69° | — | — | 65–69° |
| 11d · 2026-08-26 | 66° | 63° | 70° | — | 82° | — | — | 63–82° |
| 10d · 2026-08-27 | 71° | 57° | 70° | — | 70° | — | — | 57–71° |
| 9d · 2026-08-28 | 68° | 68° | 67° | 78° | 64° | — | — | 64–78° |
| 8d · 2026-08-29 | 71° | 77° | 68° | 73° | 79° | — | — | 68–79° |
| 7d · 2026-08-30 | 73° | 69° | 77° | 68° | 75° | — | — | 68–77° |
| 6d · 2026-08-31 | 77° | 72° | 82° | 82° | 79° | 73° | 76° | 72–82° |
| 5d · 2026-09-01 | 78° | 77° | 80° | 80° | 75° | 78° | 79° | 75–80° |
| 4d · 2026-09-02 | 76° | 76° | 79° | 73° | 75° | 80° | 79° | 73–80° |
| 3d · 2026-09-03 | 76° | 76° | 76° | 77° | 78° | 78° | 76° | 76–78° |
| 2d · 2026-09-04 | 75° | 76° | 76° | 76° | 78° | 78° | 76° | 75–78° |
| 1d · 2026-09-05 | 76° | 76° | 76° | 77° | 79° | 78° | 77° | 76–79° |
| 0d · 2026-09-06 | 77° | 76° | 79° | 77° | 79° | 78° | 78° | 76–79° |
| actual | 81° |
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.