Was the forecast right for Chicago on Wed Aug 26?
Chicago, Illinois · daily high temperature in °F · forecasts from each model's archived runs, verified against the MDW observations
6 days out, 7 models put Chicago's Wed Aug 26 high anywhere from 80° to 85°;by the final call, the day before, the field had settled to a median of 85°. The day verified at 85° against the MDW observations — drizzle.
UKMO landed closest, off by 0.2°. ECMWF ran 4° cool.
What every model said, at every lead
Daily-high calls for Wed Aug 26 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 Chicago scoreboard shows them, labelled.
| Lead | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 6d · 2026-08-20 | 80° | 84° | 82° | 82° | 85° | 82° | 85° | 80–85° |
| 5d · 2026-08-21 | 82° | 84° | 83° | 84° | 85° | 89° | 86° | 82–89° |
| 4d · 2026-08-22 | 82° | 84° | 81° | 82° | 85° | 83° | 84° | 81–85° |
| 3d · 2026-08-23 | 80° | 84° | 83° | 84° | 83° | 86° | 86° | 80–86° |
| 2d · 2026-08-24 | 82° | 83° | 84° | 83° | 84° | 85° | 83° | 82–85° |
| 1d · 2026-08-25 | 82° | 82° | 81° | 88° | 86° | 86° | 85° | 81–88° |
| 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 Chicago — 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 MDW 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.