Was the forecast right for Denver on Wed Aug 5?
Denver, Colorado · daily high temperature in °F · forecasts from each model's archived runs, verified against the ECMWF IFS analysis
11 days out, 4 models put Denver's Wed Aug 5 high anywhere from 83° to 103°;by the final call, the day before, the field had settled to a median of 86°. The day verified at 85° against the ECMWF IFS analysis — cloudy.
ICON landed closest, off by 0.0°. GFS ran 2° warm.
What every model said, at every lead
Daily-high calls for Wed Aug 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 |
|---|---|---|---|---|---|---|---|---|
| 11d · 2026-07-25 | 83° | 88° | 96° | — | 103° | — | — | 83–103° |
| 10d · 2026-07-26 | 88° | 95° | 96° | — | 86° | — | — | 86–96° |
| 9d · 2026-07-27 | 87° | 88° | 100° | 94° | 68° | — | — | 68–100° |
| 8d · 2026-07-28 | 91° | 88° | 101° | 91° | 91° | — | — | 88–101° |
| 7d · 2026-07-29 | 88° | 84° | 88° | 81° | 89° | — | — | 81–89° |
| 6d · 2026-07-30 | 84° | 76° | 90° | 83° | 74° | 87° | 84° | 74–90° |
| 5d · 2026-07-31 | 77° | 86° | 84° | 85° | 100° | 95° | 83° | 77–100° |
| 4d · 2026-08-01 | 78° | 84° | 84° | 81° | 94° | 86° | 84° | 78–94° |
| 3d · 2026-08-02 | 81° | 85° | 79° | 80° | 90° | 83° | 80° | 79–90° |
| 2d · 2026-08-03 | 84° | 86° | 84° | 82° | 92° | 84° | 84° | 82–92° |
| 1d · 2026-08-04 | 84° | 86° | 87° | 83° | 87° | 85° | 86° | 83–87° |
| actual | 85° |
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 ECMWF IFS analysis (temperature_2m_max). 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.