Was the forecast right for Atlanta on Fri Sep 18?
Atlanta, Georgia · daily high temperature in °C · forecasts from each model's archived runs, verified against the ATL observations
13 days out, 4 models put Atlanta's Fri Sep 18 high anywhere from 27° to 34°; by the final call the field had settled to a median of 34°. The day verified at 34° against the ATL observations — drizzle.
GEM landed closest, off by 0.1°. GFS ran 3° hot.
What every model said, at every lead
Daily-high calls for Fri Sep 18 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 | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-09-03 | — | 24° | — | — | 32° | — | — | 24–32° |
| 14d · 2026-09-04 | 32° | 27° | — | — | 33° | — | — | 27–33° |
| 13d · 2026-09-05 | 32° | 27° | 34° | — | 33° | — | — | 27–34° |
| 12d · 2026-09-06 | 29° | 29° | 27° | — | 24° | — | — | 24–29° |
| 11d · 2026-09-07 | 31° | 25° | 29° | — | 29° | — | — | 25–31° |
| 10d · 2026-09-08 | 31° | 30° | 29° | — | 36° | — | — | 29–36° |
| 9d · 2026-09-09 | 29° | 30° | 32° | — | 36° | — | — | 29–36° |
| 8d · 2026-09-10 | 30° | 30° | 32° | 34° | 33° | — | — | 30–34° |
| 7d · 2026-09-11 | 34° | 32° | 33° | 33° | 30° | — | — | 30–34° |
| 6d · 2026-09-12 | 33° | 31° | 30° | 30° | 35° | 33° | — | 30–35° |
| 5d · 2026-09-13 | 33° | 32° | 36° | 31° | 33° | 27° | 33° | 27–36° |
| 4d · 2026-09-14 | 34° | 31° | 35° | 32° | 33° | 33° | 32° | 31–35° |
| 3d · 2026-09-15 | 34° | 33° | 36° | 36° | 35° | 32° | 32° | 32–36° |
| 2d · 2026-09-16 | 34° | 34° | 36° | 33° | 36° | 34° | 33° | 33–36° |
| 1d · 2026-09-17 | 33° | 34° | 36° | 34° | 36° | 34° | 33° | 33–36° |
| 0d · 2026-09-18 | 33° | 35° | 36° | 34° | 36° | 34° | 33° | 33–36° |
| actual | 34° |
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 ATL observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.