Was the forecast right for London on Tue Sep 29?
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 Tue Sep 29 high anywhere from 56° to 81°;by the final call, the day before, the field had settled to a median of 77°. The day verified at 82° against the EGLL observations — drizzle.
UKMO landed closest, off by 3.2°. AIGFS ran 10° cool.
What every model said, at every lead
Daily-high calls for Tue Sep 29 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 · 2026-09-14 | — | 67° | — | — | 64° | — | — | 64–67° |
| 14d · 2026-09-15 | 70° | 56° | 81° | — | 63° | — | — | 56–81° |
| 13d · 2026-09-16 | 65° | 59° | 61° | — | 70° | — | — | 59–70° |
| 12d · 2026-09-17 | 61° | 61° | 60° | — | 73° | — | — | 60–73° |
| 11d · 2026-09-18 | 70° | 64° | 65° | — | 61° | — | — | 61–70° |
| 10d · 2026-09-19 | 78° | 67° | 64° | — | 63° | — | — | 63–78° |
| 9d · 2026-09-20 | 70° | 68° | 78° | 70° | 76° | — | — | 68–78° |
| 8d · 2026-09-21 | 72° | 70° | 70° | 67° | 70° | — | — | 67–72° |
| 7d · 2026-09-22 | 73° | 71° | 67° | 70° | 68° | — | — | 67–73° |
| 6d · 2026-09-23 | 74° | 72° | 69° | 78° | 75° | 82° | 75° | 69–82° |
| 5d · 2026-09-24 | 77° | 72° | 80° | 74° | 70° | 81° | 78° | 70–81° |
| 4d · 2026-09-25 | 76° | 74° | 76° | 73° | 65° | 77° | 79° | 65–79° |
| 3d · 2026-09-26 | 76° | 75° | 75° | 77° | 72° | 78° | 74° | 72–78° |
| 2d · 2026-09-27 | 74° | 73° | 78° | 78° | 68° | 80° | 76° | 68–80° |
| 1d · 2026-09-28 | 74° | 72° | 76° | 78° | 77° | 78° | 79° | 72–79° |
| actual | 82° |
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.