Was the forecast right for London on Thu Aug 27?
London, England · daily high temperature in °F · forecasts from each model's archived runs, verified against the EGLL observations
5 days out, 7 models put London's Thu Aug 27 high anywhere from 71° to 77°;by the final call, the day before, the field had settled to a median of 74°. The day verified at 77° against the EGLL observations, with 0.17 in of precipitation — thunderstorms.
ECMWF landed closest, off by 0.1°. AIFS ran 5° cool.
What every model said, at every lead
Daily-high calls for Thu Aug 27 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 |
|---|---|---|---|---|---|---|---|---|
| 5d · 2026-08-22 | 74° | 75° | 74° | 71° | 77° | 75° | 73° | 71–77° |
| 4d · 2026-08-23 | 75° | 75° | 75° | 71° | 78° | 72° | 73° | 71–78° |
| 3d · 2026-08-24 | 75° | 77° | 74° | 74° | 78° | 77° | 76° | 74–78° |
| 2d · 2026-08-25 | 73° | 74° | 74° | 72° | 79° | 76° | 74° | 72–79° |
| 1d · 2026-08-26 | 72° | 72° | 77° | 74° | 74° | 76° | 76° | 72–77° |
| actual | 77° |
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.