Was the forecast right for Denver on Thu Sep 24?
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 Thu Sep 24 high anywhere from 66° to 88°;by the final call, the day before, the field had settled to a median of 70°. The day verified at 71° against the DEN observations, with 0.01 in of precipitation — drizzle.
AIFS landed closest, off by 0.8°. ECMWF ran 5° warm.
What every model said, at every lead
Daily-high calls for Thu Sep 24 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 · 2026-09-09 | — | 55° | — | — | 82° | — | — | 55–82° |
| 14d · 2026-09-10 | 66° | 86° | 72° | — | 88° | — | — | 66–88° |
| 13d · 2026-09-11 | 79° | 81° | 74° | — | 87° | — | — | 74–87° |
| 12d · 2026-09-12 | 78° | 72° | 80° | — | 83° | — | — | 72–83° |
| 11d · 2026-09-13 | 80° | 81° | 75° | — | 74° | — | — | 74–81° |
| 10d · 2026-09-14 | 65° | 75° | 74° | — | 82° | — | — | 65–82° |
| 9d · 2026-09-15 | 82° | 83° | 78° | 80° | 86° | — | — | 78–86° |
| 8d · 2026-09-16 | 78° | 75° | 69° | 78° | 73° | — | — | 69–78° |
| 7d · 2026-09-17 | 71° | 70° | 76° | 76° | 77° | — | — | 70–77° |
| 6d · 2026-09-18 | 78° | 73° | 76° | 79° | 78° | 78° | 80° | 73–80° |
| 5d · 2026-09-19 | 77° | 77° | 75° | 78° | 74° | 77° | 75° | 74–78° |
| 4d · 2026-09-20 | 76° | 74° | 69° | 78° | 76° | 73° | 76° | 69–78° |
| 3d · 2026-09-21 | 66° | 67° | 65° | 65° | 65° | 63° | 68° | 63–68° |
| 2d · 2026-09-22 | 65° | 67° | 72° | 64° | 71° | 75° | 73° | 64–75° |
| 1d · 2026-09-23 | 70° | 69° | 76° | 67° | 75° | 68° | 75° | 67–76° |
| actual | 71° |
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.