Was the forecast right for Denver on Tue Sep 15?
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 Tue Sep 15 high anywhere from 65° to 88°; by the final call the field had settled to a median of 72°. The day verified at 71° against the DEN observations — drizzle.
GEM landed closest, off by 0.2°. ECMWF ran 5° hot.
What every model said, at every lead
Daily-high calls for Tue Sep 15 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 · 2026-08-31 | — | 71° | — | — | 71° | — | — | 71–71° |
| 14d · 2026-09-01 | 61° | 78° | — | — | 78° | — | — | 61–78° |
| 13d · 2026-09-02 | 79° | 65° | 85° | — | 88° | — | — | 65–88° |
| 12d · 2026-09-03 | 91° | 80° | 92° | — | 84° | — | — | 80–92° |
| 11d · 2026-09-04 | 83° | 85° | 92° | — | 89° | — | — | 83–92° |
| 10d · 2026-09-05 | 87° | 69° | 92° | — | 82° | — | — | 69–92° |
| 9d · 2026-09-06 | 85° | 71° | 76° | — | 83° | — | — | 71–85° |
| 8d · 2026-09-07 | 76° | 67° | 81° | 86° | 76° | — | — | 67–86° |
| 7d · 2026-09-08 | 77° | 76° | 81° | 85° | 85° | — | — | 76–85° |
| 6d · 2026-09-09 | 74° | 75° | 78° | 81° | 85° | 75° | — | 74–85° |
| 5d · 2026-09-10 | 68° | 61° | 67° | 83° | 74° | 80° | 64° | 61–83° |
| 4d · 2026-09-11 | 69° | 65° | 66° | 76° | 77° | 67° | 70° | 65–77° |
| 3d · 2026-09-12 | 70° | 69° | 76° | 69° | 74° | 69° | 66° | 66–76° |
| 2d · 2026-09-13 | 68° | 66° | 78° | 75° | 74° | 68° | 71° | 66–78° |
| 1d · 2026-09-14 | 71° | 70° | 75° | 74° | 76° | 71° | 76° | 70–76° |
| 0d · 2026-09-15 | 72° | 72° | 76° | 71° | 75° | 70° | 75° | 70–76° |
| actual | 71° |
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.