The Spread

Was the forecast right for Chicago on Fri Aug 14?

Chicago, Illinois · daily high temperature in °F · 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 78° to 81°; by the final call the field had settled to a median of 77°. The ECMWF IFS analysis says the day verified at 78° with 0.18 in of precipitation — drizzle.

GEM landed closest, off by 0.3°. UKMO ran 3° hot.

13 days out the models said 78–81; it hit 78. GEM led (off 0.3°F); UKMO ran 3°F 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 71° 78° 71–78°
14d · 2026-07-31 82° 76° 72° 72–82°
13d · 2026-08-01 80° 80° 78° 81° 78–81°
12d · 2026-08-02 81° 82° 81° 93° 81–93°
11d · 2026-08-03 82° 71° 85° 73° 71–85°
10d · 2026-08-04 75° 78° 79° 70° 70–79°
9d · 2026-08-05 71° 74° 75° 70° 70–75°
8d · 2026-08-06 76° 68° 71° 73° 74° 68–76°
7d · 2026-08-07 77° 70° 81° 71° 82° 70–82°
6d · 2026-08-08 73° 68° 76° 71° 76° 77° 68–77°
5d · 2026-08-09 76° 70° 76° 76° 73° 74° 77° 70–77°
4d · 2026-08-10 75° 71° 78° 73° 73° 75° 82° 71–82°
3d · 2026-08-11 77° 76° 76° 72° 74° 81° 78° 72–81°
2d · 2026-08-12 75° 73° 77° 73° 77° 79° 82° 73–82°
1d · 2026-08-13 75° 78° 77° 75° 74° 75° 81° 74–81°
0d · 2026-08-14 75° 79° 76° 77° 76° 78° 80° 75–80°
actual 78°

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.