Was the forecast right for Denver on Sun Sep 13?
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 Sun Sep 13 high anywhere from 45° to 85°; by the final call the field had settled to a median of 91°. The day verified at 94° against the DEN observations — partly cloudy.
ECMWF landed closest, off by 0.3°. AIGFS ran 4° cold.
What every model said, at every lead
Daily-high calls for Sun Sep 13 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 · 2026-08-29 | — | 91° | — | — | 91° | — | — | 91–91° |
| 14d · 2026-08-30 | 87° | 82° | — | — | 92° | — | — | 82–92° |
| 13d · 2026-08-31 | 77° | 70° | 85° | — | 45° | — | — | 45–85° |
| 12d · 2026-09-01 | 78° | 82° | 76° | — | 86° | — | — | 76–86° |
| 11d · 2026-09-02 | 70° | 71° | 94° | — | 81° | — | — | 70–94° |
| 10d · 2026-09-03 | 86° | 77° | 91° | — | 87° | — | — | 77–91° |
| 9d · 2026-09-04 | 86° | 80° | 88° | — | 74° | — | — | 74–88° |
| 8d · 2026-09-05 | 84° | 90° | 84° | 78° | 62° | — | — | 62–90° |
| 7d · 2026-09-06 | 95° | 85° | 79° | 96° | 52° | — | — | 52–96° |
| 6d · 2026-09-07 | 90° | 89° | 93° | 94° | 89° | 71° | — | 71–94° |
| 5d · 2026-09-08 | 91° | 83° | 96° | 93° | 86° | 87° | 88° | 83–96° |
| 4d · 2026-09-09 | 91° | 93° | 95° | 92° | 93° | 93° | 94° | 91–95° |
| 3d · 2026-09-10 | 93° | 91° | 95° | 92° | 90° | 92° | 95° | 90–95° |
| 2d · 2026-09-11 | 92° | 91° | 94° | 91° | 92° | 93° | 92° | 91–94° |
| 1d · 2026-09-12 | 91° | 90° | 94° | 90° | 91° | 91° | 92° | 90–94° |
| 0d · 2026-09-13 | 91° | 90° | 94° | 90° | 92° | 90° | 92° | 90–94° |
| actual | 94° |
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.