Was the forecast right for Denver on Wed Sep 9?
Denver, Colorado · daily high temperature in °F · forecasts from each model's archived runs, verified against the DEN observations
13 days out, 4 models put Denver's Wed Sep 9 high anywhere from 61° to 90°; by the final call the field had settled to a median of 81°. The day verified at 82° against the DEN observations — partly cloudy.
ECMWF landed closest, off by 0.2°. AIGFS ran 4° cold.
What every model said, at every lead
Daily-high calls for Wed Sep 9 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 |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-08-25 | — | 70° | — | — | 68° | — | — | 68–70° |
| 14d · 2026-08-26 | 79° | 87° | — | — | 80° | — | — | 79–87° |
| 13d · 2026-08-27 | 90° | 78° | 61° | — | 76° | — | — | 61–90° |
| 12d · 2026-08-28 | 89° | 84° | 87° | — | 84° | — | — | 84–89° |
| 11d · 2026-08-29 | 92° | 85° | 93° | — | 80° | — | — | 80–93° |
| 10d · 2026-08-30 | 74° | 89° | 72° | — | 84° | — | — | 72–89° |
| 9d · 2026-08-31 | 89° | 82° | 74° | — | 88° | — | — | 74–89° |
| 8d · 2026-09-01 | 79° | 80° | 83° | 87° | 89° | — | — | 79–89° |
| 7d · 2026-09-02 | 88° | 68° | 86° | 76° | 82° | — | — | 68–88° |
| 6d · 2026-09-03 | 90° | 87° | 90° | 90° | 88° | 87° | — | 87–90° |
| 5d · 2026-09-04 | 83° | 86° | 86° | 88° | 85° | 86° | 84° | 83–88° |
| 4d · 2026-09-05 | 83° | 84° | 86° | 84° | 85° | 82° | 80° | 80–86° |
| 3d · 2026-09-06 | 80° | 78° | 83° | 79° | 81° | 86° | 85° | 78–86° |
| 2d · 2026-09-07 | 80° | 77° | 80° | 79° | 83° | 79° | 82° | 77–83° |
| 1d · 2026-09-08 | 81° | 78° | 82° | 80° | 80° | 80° | 81° | 78–82° |
| 0d · 2026-09-09 | 82° | 78° | 82° | 81° | 80° | 80° | 81° | 78–82° |
| 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 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.