Was the forecast right for London on Tue Aug 18?
London, England · daily high temperature in °F · forecasts from each model's archived runs, verified against the ECMWF IFS analysis
7 days out, 6 models put London's Tue Aug 18 high anywhere from 68° to 76°; by the final call the field had settled to a median of 77°. The day verified at 74° against the ECMWF IFS analysis, with 0.04 in of precipitation — drizzle.
AIGFS landed closest, off by 0.8°. GFS ran 7° hot.
What every model said, at every lead
Daily-high calls for Tue Aug 18 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 |
|---|---|---|---|---|---|---|---|---|
| 7d · 2026-08-11 | 70° | 68° | 73° | 73° | 71° | 76° | — | 68–76° |
| 6d · 2026-08-12 | 72° | 69° | 73° | 74° | 76° | 89° | 74° | 69–89° |
| 5d · 2026-08-13 | 72° | 78° | 78° | 76° | 71° | 79° | 80° | 71–80° |
| 4d · 2026-08-14 | 74° | 75° | 82° | 79° | 83° | 76° | 78° | 74–83° |
| 3d · 2026-08-15 | 74° | 75° | 76° | 80° | 80° | 81° | 74° | 74–81° |
| 2d · 2026-08-16 | 73° | 74° | 79° | 78° | 77° | 76° | 77° | 73–79° |
| 1d · 2026-08-17 | 74° | 75° | 77° | 78° | 77° | 76° | 77° | 74–78° |
| 0d · 2026-08-18 | 75° | 75° | 77° | 80° | 81° | 76° | 78° | 75–81° |
| 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.