Was the forecast right for Denver on Thu Sep 10?
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 Thu Sep 10 high anywhere from 83° to 92°; by the final call the field had settled to a median of 87°. The day verified at 89° against the DEN observations — partly cloudy.
AIFS landed closest, off by 0.9°. AIGFS ran 4° cold.
What every model said, at every lead
Daily-high calls for Thu Sep 10 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 · 2026-08-26 | — | 85° | — | — | 84° | — | — | 84–85° |
| 14d · 2026-08-27 | 90° | 76° | — | — | 78° | — | — | 76–90° |
| 13d · 2026-08-28 | 92° | 88° | 83° | — | 89° | — | — | 83–92° |
| 12d · 2026-08-29 | 75° | 88° | 95° | — | 86° | — | — | 75–95° |
| 11d · 2026-08-30 | 76° | 76° | 69° | — | 91° | — | — | 69–91° |
| 10d · 2026-08-31 | 78° | 70° | 78° | — | 86° | — | — | 70–86° |
| 9d · 2026-09-01 | 83° | 67° | 78° | — | 87° | — | — | 67–87° |
| 8d · 2026-09-02 | 87° | 74° | 86° | 83° | 84° | — | — | 74–87° |
| 7d · 2026-09-03 | 88° | 88° | 90° | 88° | 89° | — | — | 88–90° |
| 6d · 2026-09-04 | 88° | 90° | 92° | 85° | 90° | 87° | — | 85–92° |
| 5d · 2026-09-05 | 89° | 81° | 91° | 84° | 89° | 90° | 84° | 81–91° |
| 4d · 2026-09-06 | 89° | 86° | 92° | 91° | 89° | 92° | 90° | 86–92° |
| 3d · 2026-09-07 | 88° | 86° | 87° | 88° | 89° | 87° | 90° | 86–90° |
| 2d · 2026-09-08 | 88° | 86° | 90° | 87° | 86° | 87° | 89° | 86–90° |
| 1d · 2026-09-09 | 88° | 86° | 89° | 85° | 86° | 86° | 88° | 85–89° |
| 0d · 2026-09-10 | 88° | 85° | 88° | 86° | 87° | 86° | 87° | 85–88° |
| actual | 89° |
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.