Was the forecast right for Denver on Fri Sep 4?
Denver, Colorado · daily high temperature in °F · forecasts from each model's archived runs, verified against the DEN observations
10 days out, 4 models put Denver's Fri Sep 4 high anywhere from 66° to 91°; by the final call the field had settled to a median of 91°. The day verified at 93° against the DEN observations — partly cloudy.
ECMWF landed closest, off by 0.1°. GFS ran 5° cold.
What every model said, at every lead
Daily-high calls for Fri Sep 4 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 Denver scoreboard shows them, labelled.
| Lead | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 10d · 2026-08-25 | 80° | 66° | 91° | — | 87° | — | — | 66–91° |
| 9d · 2026-08-26 | 70° | 84° | 85° | — | 80° | — | — | 70–85° |
| 8d · 2026-08-27 | 84° | 87° | 94° | 76° | 84° | — | — | 76–94° |
| 7d · 2026-08-28 | 89° | 87° | 94° | 91° | 88° | — | — | 87–94° |
| 6d · 2026-08-29 | 89° | 88° | 92° | 92° | 83° | 86° | — | 83–92° |
| 5d · 2026-08-30 | 91° | 86° | 91° | 90° | 91° | 87° | 93° | 86–93° |
| 4d · 2026-08-31 | 92° | 88° | 88° | 88° | 86° | 84° | 92° | 84–92° |
| 3d · 2026-09-01 | 92° | 89° | 92° | 90° | 90° | 87° | 88° | 87–92° |
| 2d · 2026-09-02 | 92° | 90° | 91° | 90° | 91° | 88° | 91° | 88–92° |
| 1d · 2026-09-03 | 92° | 90° | 91° | 90° | 90° | 89° | 91° | 89–92° |
| 0d · 2026-09-04 | 92° | 89° | 93° | 91° | 88° | 90° | 91° | 88–93° |
| actual | 93° |
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 Denver — 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 DEN observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.