Was the forecast right for Chicago on Sat Sep 19?
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 Sat Sep 19 high anywhere from 66° to 78°; by the final call the field had settled to a median of 80°. The day verified at 72° against the MDW observations, with 1.01 in of precipitation — thunderstorms.
AIFS landed closest, off by 0.2°. ECMWF ran 10° warm.
What every model said, at every lead
Daily-high calls for Sat Sep 19 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 · 2026-09-04 | — | 64° | — | — | 68° | — | — | 64–68° |
| 14d · 2026-09-05 | 73° | 74° | — | — | 85° | — | — | 73–85° |
| 13d · 2026-09-06 | 73° | 69° | 66° | — | 78° | — | — | 66–78° |
| 12d · 2026-09-07 | 75° | 61° | 74° | — | 72° | — | — | 61–75° |
| 11d · 2026-09-08 | 64° | 68° | 66° | — | 68° | — | — | 64–68° |
| 10d · 2026-09-09 | 65° | 80° | 84° | — | 84° | — | — | 65–84° |
| 9d · 2026-09-10 | 68° | 73° | 72° | — | 78° | — | — | 68–78° |
| 8d · 2026-09-11 | 71° | 75° | 68° | 73° | 70° | — | — | 68–75° |
| 7d · 2026-09-12 | 72° | 68° | 73° | 70° | 66° | — | — | 66–73° |
| 6d · 2026-09-13 | 69° | 68° | 83° | 80° | 86° | 89° | — | 68–89° |
| 5d · 2026-09-14 | 70° | 82° | 89° | 90° | 93° | 77° | 84° | 70–93° |
| 4d · 2026-09-15 | 70° | 72° | 82° | 79° | 75° | 80° | 73° | 70–82° |
| 3d · 2026-09-16 | 73° | 81° | 85° | 78° | 86° | 83° | 87° | 73–87° |
| 2d · 2026-09-17 | 71° | 70° | 79° | 70° | 69° | 78° | 76° | 69–79° |
| 1d · 2026-09-18 | 72° | 69° | 82° | 70° | 69° | 76° | 74° | 69–82° |
| 0d · 2026-09-19 | 72° | 70° | 82° | 81° | 71° | 80° | 80° | 70–82° |
| 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.