Was the forecast right for Denver on Wed Sep 23?
Denver, Colorado · daily high temperature in °F · forecasts from each model's archived runs, verified against the DEN observations
14 days out, 4 models put Denver's Wed Sep 23 high anywhere from 67° to 74°;by the final call, the day before, the field had settled to a median of 73°. The day verified at 72° against the DEN observations — drizzle.
AIFS landed closest, off by 0.1°. GEM ran 3° warm.
What every model said, at every lead
Daily-high calls for Wed Sep 23 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 · 2026-09-08 | — | 80° | — | — | 79° | — | — | 79–80° |
| 14d · 2026-09-09 | 72° | 74° | 68° | — | 67° | — | — | 67–74° |
| 13d · 2026-09-10 | 70° | 76° | 76° | — | 86° | — | — | 70–86° |
| 12d · 2026-09-11 | 82° | 79° | 75° | — | 78° | — | — | 75–82° |
| 11d · 2026-09-12 | 65° | 77° | 77° | — | 81° | — | — | 65–81° |
| 10d · 2026-09-13 | 80° | 79° | 76° | — | 70° | — | — | 70–80° |
| 9d · 2026-09-14 | 73° | 78° | 72° | 78° | 74° | — | — | 72–78° |
| 8d · 2026-09-15 | 79° | 78° | 76° | 79° | 77° | — | — | 76–79° |
| 7d · 2026-09-16 | 75° | 72° | 72° | 78° | 77° | — | — | 72–78° |
| 6d · 2026-09-17 | 73° | 72° | 72° | 77° | 76° | 76° | 73° | 72–77° |
| 5d · 2026-09-18 | 72° | 72° | 76° | 78° | 76° | 77° | 78° | 72–78° |
| 4d · 2026-09-19 | 75° | 71° | 76° | 73° | 76° | 75° | 76° | 71–76° |
| 3d · 2026-09-20 | 74° | 71° | 78° | 72° | 73° | 77° | 75° | 71–78° |
| 2d · 2026-09-21 | 73° | 72° | 76° | 76° | 74° | 76° | 80° | 72–80° |
| 1d · 2026-09-22 | 72° | 73° | 75° | 75° | 75° | 73° | 72° | 72–75° |
| actual | 72° |
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.