Was the forecast right for London on Wed Aug 19?
London, England · daily high temperature in °F · forecasts from each model's archived runs, verified against the ECMWF IFS analysis
8 days out, 5 models put London's Wed Aug 19 high anywhere from 68° to 78°; by the final call the field had settled to a median of 74°. The day verified at 74° against the ECMWF IFS analysis, with 0.09 in of precipitation — drizzle.
UKMO landed closest, off by 0.2°. AIFS ran 3° cold.
What every model said, at every lead
Daily-high calls for Wed Aug 19 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 |
|---|---|---|---|---|---|---|---|---|
| 8d · 2026-08-11 | 68° | 69° | 77° | 78° | 68° | — | — | 68–78° |
| 7d · 2026-08-12 | 70° | 67° | 70° | 72° | 75° | — | — | 67–75° |
| 6d · 2026-08-13 | 73° | 70° | 76° | 74° | 75° | 76° | 77° | 70–77° |
| 5d · 2026-08-14 | 72° | 72° | 71° | 71° | 73° | 76° | 68° | 68–76° |
| 4d · 2026-08-15 | 71° | 72° | 74° | 74° | 77° | 76° | 74° | 71–77° |
| 3d · 2026-08-16 | 72° | 71° | 73° | 75° | 75° | 74° | 72° | 71–75° |
| 2d · 2026-08-17 | 72° | 71° | 74° | 75° | 73° | 76° | 74° | 71–76° |
| 1d · 2026-08-18 | 73° | 71° | 74° | 74° | 76° | 74° | 74° | 71–76° |
| 0d · 2026-08-19 | 71° | 72° | 77° | 74° | 77° | 76° | 74° | 71–77° |
| actual | 74° |
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 ECMWF IFS analysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.