Was the forecast right for Denver on Thu Sep 3?
Denver, Colorado · daily high temperature in °C · forecasts from each model's archived runs, verified against the DEN observations
10 days out, 4 models put Denver's Thu Sep 3 high anywhere from 27° to 31°;by the final call, the day before, the field had settled to a median of 32°. The day verified at 33° against the DEN observations — partly cloudy.
AIFS landed closest, off by 0.4°. AIGFS ran 2° cool.
What every model said, at every lead
Daily-high calls for Thu Sep 3 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 |
|---|---|---|---|---|---|---|---|---|
| 10d · 2026-08-24 | 27° | 28° | 28° | — | 31° | — | — | 27–31° |
| 9d · 2026-08-25 | 23° | 28° | 33° | 28° | 31° | — | — | 23–33° |
| 8d · 2026-08-26 | 22° | 22° | 33° | 29° | 28° | — | — | 22–33° |
| 7d · 2026-08-27 | 32° | 32° | 31° | 30° | 30° | — | — | 30–32° |
| 6d · 2026-08-28 | 32° | 30° | 31° | 28° | 31° | 28° | 31° | 28–32° |
| 5d · 2026-08-29 | 32° | 30° | 32° | 30° | 32° | 32° | 32° | 30–32° |
| 4d · 2026-08-30 | 32° | 31° | 32° | 30° | 32° | 30° | 30° | 30–32° |
| 3d · 2026-08-31 | 33° | 31° | 34° | 32° | 33° | 31° | 31° | 31–34° |
| 2d · 2026-09-01 | 32° | 32° | 32° | 31° | 32° | 32° | 31° | 31–32° |
| 1d · 2026-09-02 | 33° | 31° | 32° | 32° | 32° | 32° | 32° | 31–33° |
| actual | 33° |
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.