Was the forecast right for London on Wed Sep 9?
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 Wed Sep 9 high anywhere from 62° to 77°;by the final call, the day before, the field had settled to a median of 66°. The day verified at 66° against the EGLL observations — cloudy.
GEM landed closest, off by 0.1°. AIGFS ran 3° cool.
What every model said, at every lead
Daily-high calls for Wed Sep 9 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 · 2026-08-25 | — | 67° | — | — | 74° | — | — | 67–74° |
| 14d · 2026-08-26 | 64° | 62° | 77° | — | 66° | — | — | 62–77° |
| 13d · 2026-08-27 | 60° | 68° | 63° | — | 78° | — | — | 60–78° |
| 12d · 2026-08-28 | 68° | 62° | 65° | — | 68° | — | — | 62–68° |
| 11d · 2026-08-29 | 67° | 65° | 71° | — | 65° | — | — | 65–71° |
| 10d · 2026-08-30 | 67° | 61° | 69° | — | 67° | — | — | 61–69° |
| 9d · 2026-08-31 | 67° | 58° | 69° | 63° | 71° | — | — | 58–71° |
| 8d · 2026-09-01 | 63° | 66° | 62° | 65° | 68° | — | — | 62–68° |
| 7d · 2026-09-02 | 64° | 65° | 64° | 66° | 66° | — | — | 64–66° |
| 6d · 2026-09-03 | 63° | 63° | 64° | 67° | 68° | 66° | 63° | 63–68° |
| 5d · 2026-09-04 | 64° | 63° | 65° | 66° | 70° | 67° | 64° | 63–70° |
| 4d · 2026-09-05 | 63° | 65° | 68° | 66° | 68° | 66° | 66° | 63–68° |
| 3d · 2026-09-06 | 65° | 64° | 69° | 67° | 69° | 68° | 66° | 64–69° |
| 2d · 2026-09-07 | 66° | 64° | 69° | 69° | 67° | 68° | 68° | 64–69° |
| 1d · 2026-09-08 | 66° | 63° | 66° | 66° | 64° | 67° | 66° | 63–67° |
| actual | 66° |
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. The actual values are the ones in hand when this receipt was settled, usually 2 days after the date; a correction published after that is not carried into it. Archive depth varies by city; receipts exist only for dates the archive watched arrive.