Was the forecast right for Denver on Sat Sep 5?
Denver, Colorado · daily high temperature in °C · forecasts from each model's archived runs, verified against the DEN observations
12 days out, 4 models put Denver's Sat Sep 5 high anywhere from 23° to 30°;by the final call, the day before, the field had settled to a median of 33°. The day verified at 34° against the DEN observations — partly cloudy.
ECMWF landed closest, off by 1.3°. GFS ran 3° cool.
What every model said, at every lead
Daily-high calls for Sat Sep 5 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 |
|---|---|---|---|---|---|---|---|---|
| 12d · 2026-08-24 | 30° | 23° | 23° | — | 30° | — | — | 23–30° |
| 11d · 2026-08-25 | 20° | 31° | 25° | — | 31° | — | — | 20–31° |
| 10d · 2026-08-26 | 26° | 28° | 33° | — | 34° | — | — | 26–34° |
| 9d · 2026-08-27 | 32° | 24° | 36° | 23° | 29° | — | — | 23–36° |
| 8d · 2026-08-28 | 30° | 32° | 33° | 33° | 32° | — | — | 30–33° |
| 7d · 2026-08-29 | 33° | 31° | 32° | 33° | 31° | — | — | 31–33° |
| 6d · 2026-08-30 | 32° | 31° | 32° | 32° | 32° | 32° | 32° | 31–32° |
| 5d · 2026-08-31 | 33° | 32° | 34° | 33° | 32° | 29° | 32° | 29–34° |
| 4d · 2026-09-01 | 33° | 32° | 34° | 32° | 31° | 30° | 32° | 30–34° |
| 3d · 2026-09-02 | 33° | 32° | 33° | 32° | 31° | 31° | 33° | 31–33° |
| 2d · 2026-09-03 | 33° | 32° | 33° | 32° | 32° | 31° | 33° | 31–33° |
| 1d · 2026-09-04 | 33° | 32° | 33° | 33° | 31° | 32° | 33° | 31–33° |
| actual | 34° |
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. The actual values are the ones in hand when this receipt was settled, usually 2 days after the date; a correction published after that is not carried into it. Archive depth varies by city; receipts exist only for dates the archive watched arrive.