Was the forecast right for Chicago on Mon Sep 14?
Chicago, Illinois · daily high temperature in °F · forecasts from each model's archived runs, verified against the MDW observations
13 days out, 4 models put Chicago's Mon Sep 14 high anywhere from 75° to 80°; by the final call the field had settled to a median of 73°. The day verified at 72° against the MDW observations — cloudy.
AIGFS landed closest, off by 0.2°. GFS ran 7° hot.
What every model said, at every lead
Daily-high calls for Mon Sep 14 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 · 2026-08-30 | — | 61° | — | — | 84° | — | — | 61–84° |
| 14d · 2026-08-31 | 67° | 72° | — | — | 74° | — | — | 67–74° |
| 13d · 2026-09-01 | 78° | 76° | 75° | — | 80° | — | — | 75–80° |
| 12d · 2026-09-02 | 83° | 63° | 94° | — | 96° | — | — | 63–96° |
| 11d · 2026-09-03 | 74° | 76° | 82° | — | 90° | — | — | 74–90° |
| 10d · 2026-09-04 | 84° | 71° | 78° | — | 71° | — | — | 71–84° |
| 9d · 2026-09-05 | 69° | 90° | 70° | — | 95° | — | — | 69–95° |
| 8d · 2026-09-06 | 71° | 91° | 90° | 86° | 71° | — | — | 71–91° |
| 7d · 2026-09-07 | 77° | 91° | 84° | 68° | 87° | — | — | 68–91° |
| 6d · 2026-09-08 | 75° | 71° | 80° | 68° | 80° | 63° | — | 63–80° |
| 5d · 2026-09-09 | 72° | 73° | 94° | 80° | 88° | 92° | 93° | 72–94° |
| 4d · 2026-09-10 | 70° | 78° | 75° | 74° | 88° | 76° | 71° | 70–88° |
| 3d · 2026-09-11 | 69° | 70° | 71° | 71° | 73° | 64° | 76° | 64–76° |
| 2d · 2026-09-12 | 70° | 72° | 76° | 73° | 76° | 69° | 74° | 69–76° |
| 1d · 2026-09-13 | 72° | 72° | 76° | 77° | 78° | 72° | 75° | 72–78° |
| 0d · 2026-09-14 | 70° | 72° | 73° | 73° | 79° | 73° | 76° | 70–79° |
| 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 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. Archive depth varies by city; receipts exist only for dates the archive watched arrive.