Was the forecast right for Denver on Sun Sep 27?
Denver, Colorado · daily high temperature in °C · forecasts from each model's archived runs, verified against the DEN observations
14 days out, 4 models put Denver's Sun Sep 27 high anywhere from 16° to 26°;by the final call, the day before, the field had settled to a median of 27°. The day verified at 28° against the DEN observations — cloudy.
GFS landed closest, off by 0.4°. UKMO ran 2° cool.
What every model said, at every lead
Daily-high calls for Sun Sep 27 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 · 2026-09-12 | — | 26° | — | — | 27° | — | — | 26–27° |
| 14d · 2026-09-13 | 16° | 21° | 25° | — | 26° | — | — | 16–26° |
| 13d · 2026-09-14 | 18° | 25° | 24° | — | 26° | — | — | 18–26° |
| 12d · 2026-09-15 | 28° | 25° | 29° | — | 32° | — | — | 25–32° |
| 11d · 2026-09-16 | 12° | 16° | 25° | — | 30° | — | — | 12–30° |
| 10d · 2026-09-17 | 24° | 25° | 23° | — | 28° | — | — | 23–28° |
| 9d · 2026-09-18 | 23° | 24° | 27° | 27° | 24° | — | — | 23–27° |
| 8d · 2026-09-19 | 28° | 23° | 28° | 20° | 28° | — | — | 20–28° |
| 7d · 2026-09-20 | 27° | 24° | 28° | 24° | 29° | — | — | 24–29° |
| 6d · 2026-09-21 | 27° | 26° | 28° | 26° | 28° | 28° | 26° | 26–28° |
| 5d · 2026-09-22 | 28° | 27° | 28° | 27° | 29° | 28° | 27° | 27–29° |
| 4d · 2026-09-23 | 27° | 27° | 28° | 28° | 27° | 28° | 28° | 27–28° |
| 3d · 2026-09-24 | 27° | 26° | 28° | 28° | 28° | 28° | 27° | 26–28° |
| 2d · 2026-09-25 | 27° | 26° | 28° | 27° | 28° | 28° | 27° | 26–28° |
| 1d · 2026-09-26 | 27° | 26° | 28° | 27° | 28° | 27° | 26° | 26–28° |
| actual | 28° |
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.