Was the forecast right for Chicago on Fri Sep 25?
Chicago, Illinois · daily high temperature in °F · forecasts from each model's archived runs, verified against the MDW observations
14 days out, 4 models put Chicago's Fri Sep 25 high anywhere from 63° to 85°;by the final call, the day before, the field had settled to a median of 66°. The day verified at 64° against the MDW observations — drizzle.
ECMWF landed closest, off by 0.3°. GEM ran 4° warm.
What every model said, at every lead
Daily-high calls for Fri Sep 25 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 |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-09-10 | — | 67° | — | — | 83° | — | — | 67–83° |
| 14d · 2026-09-11 | 71° | 72° | 63° | — | 85° | — | — | 63–85° |
| 13d · 2026-09-12 | 76° | 67° | 72° | — | 85° | — | — | 67–85° |
| 12d · 2026-09-13 | 69° | 78° | 70° | — | 70° | — | — | 69–78° |
| 11d · 2026-09-14 | 70° | 81° | 74° | — | 69° | — | — | 69–81° |
| 10d · 2026-09-15 | 75° | 74° | 72° | — | 79° | — | — | 72–79° |
| 9d · 2026-09-16 | 64° | 72° | 66° | 71° | 70° | — | — | 64–72° |
| 8d · 2026-09-17 | 67° | 70° | 63° | 72° | 71° | — | — | 63–72° |
| 7d · 2026-09-18 | 67° | 69° | 65° | 69° | 70° | — | — | 65–70° |
| 6d · 2026-09-19 | 68° | 68° | 65° | 68° | 70° | 69° | 67° | 65–70° |
| 5d · 2026-09-20 | 67° | 69° | 64° | 65° | 70° | 66° | 67° | 64–70° |
| 4d · 2026-09-21 | 68° | 70° | 65° | 66° | 71° | 68° | 69° | 65–71° |
| 3d · 2026-09-22 | 67° | 70° | 65° | 66° | 72° | 64° | 70° | 64–72° |
| 2d · 2026-09-23 | 65° | 68° | 64° | 65° | 66° | 64° | 66° | 64–68° |
| 1d · 2026-09-24 | 66° | 65° | 64° | 68° | 66° | 66° | 65° | 64–68° |
| actual | 64° |
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.