The Spread

Was the forecast right for Atlanta on Wed Aug 19?

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

13 days out, 4 models put Atlanta's Wed Aug 19 high anywhere from 29° to 37°; by the final call the field had settled to a median of 35°. The day verified at 35° against the ECMWF IFS analysis — cloudy.

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

13 days out the models said 29–37; it hit 35. UKMO led (off 0.3°C); GEM ran 3°C cold.
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 Wed Aug 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 Atlanta scoreboard shows them, labelled.

Lead AIFSAIGFSECMWFGEMGFSICONUKMO Range
15d · 2026-08-04 33° 33° 33–33°
14d · 2026-08-05 33° 34° 32° 32–34°
13d · 2026-08-06 29° 37° 34° 29° 29–37°
12d · 2026-08-07 34° 36° 34° 35° 34–36°
11d · 2026-08-08 33° 35° 34° 35° 33–35°
10d · 2026-08-09 32° 35° 37° 36° 32–37°
9d · 2026-08-10 33° 35° 35° 29° 29–35°
8d · 2026-08-11 34° 34° 36° 33° 36° 33–36°
7d · 2026-08-12 34° 34° 38° 33° 38° 33–38°
6d · 2026-08-13 32° 34° 35° 32° 39° 37° 32–39°
5d · 2026-08-14 32° 35° 35° 33° 38° 36° 36° 32–38°
4d · 2026-08-15 32° 34° 37° 33° 38° 36° 36° 32–38°
3d · 2026-08-16 32° 35° 38° 33° 38° 36° 35° 32–38°
2d · 2026-08-17 32° 35° 37° 33° 37° 34° 35° 32–37°
1d · 2026-08-18 32° 35° 37° 32° 35° 34° 35° 32–37°
0d · 2026-08-19 32° 35° 36° 32° 36° 34° 35° 32–36°
actual 35°

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 Atlanta — 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.