The Spread

Was the forecast right for Chicago on Fri Aug 14?

Chicago, Illinois · daily high temperature in °C · forecasts from each model's archived runs, verified against the ECMWF IFS analysis

13 days out, 4 models put Chicago's Fri Aug 14 high anywhere from 25° to 27°; by the final call the field had settled to a median of 25°. The ECMWF IFS analysis says the day verified at 25° with 4.6 mm of precipitation — drizzle.

GEM landed closest, off by 0.2°. UKMO ran 2° hot.

13 days out the models said 25–27; it hit 25. GEM led (off 0.2°C); UKMO ran 2°C hot.
The shareable card for this receipt — what this page looks like pasted into a thread.

What every model said, at every lead

Daily-high calls for Fri Aug 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 AIFSAIGFSECMWFGEMGFSICONUKMO Range
15d · 2026-07-30 22° 26° 22–26°
14d · 2026-07-31 28° 25° 22° 22–28°
13d · 2026-08-01 26° 27° 25° 27° 25–27°
12d · 2026-08-02 27° 28° 27° 34° 27–34°
11d · 2026-08-03 28° 22° 30° 23° 22–30°
10d · 2026-08-04 24° 25° 26° 21° 21–26°
9d · 2026-08-05 22° 23° 24° 21° 21–24°
8d · 2026-08-06 24° 20° 22° 23° 23° 20–24°
7d · 2026-08-07 25° 21° 27° 22° 28° 21–28°
6d · 2026-08-08 23° 20° 24° 22° 25° 25° 20–25°
5d · 2026-08-09 25° 21° 24° 25° 23° 23° 25° 21–25°
4d · 2026-08-10 24° 22° 26° 23° 23° 24° 28° 22–28°
3d · 2026-08-11 25° 25° 25° 22° 24° 27° 25° 22–27°
2d · 2026-08-12 24° 23° 25° 23° 25° 26° 28° 23–28°
1d · 2026-08-13 24° 25° 25° 24° 24° 24° 27° 24–27°
0d · 2026-08-14 24° 26° 24° 25° 25° 26° 27° 24–27°
actual 25°

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 ECMWF IFS analysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.