Was the forecast right for Atlanta on Mon Sep 21?
Atlanta, Georgia · daily high temperature in °F · forecasts from each model's archived runs, verified against the ATL observations
14 days out, 4 models put Atlanta's Mon Sep 21 high anywhere from 74° to 88°;by the final call, the day before, the field had settled to a median of 89°. The day verified at 90° against the ATL observations — drizzle.
AIGFS landed closest, off by 0.4°. GFS ran 5° warm.
What every model said, at every lead
Daily-high calls for Mon Sep 21 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 · 2026-09-06 | — | 77° | — | — | 73° | — | — | 73–77° |
| 14d · 2026-09-07 | 74° | 77° | 88° | — | 84° | — | — | 74–88° |
| 13d · 2026-09-08 | 63° | 83° | 82° | — | 94° | — | — | 63–94° |
| 12d · 2026-09-09 | 84° | 73° | 78° | — | 75° | — | — | 73–84° |
| 11d · 2026-09-10 | 83° | 79° | 74° | — | 79° | — | — | 74–83° |
| 10d · 2026-09-11 | 75° | 70° | 92° | — | 74° | — | — | 70–92° |
| 9d · 2026-09-12 | 87° | 84° | 87° | 92° | 76° | — | — | 76–92° |
| 8d · 2026-09-13 | 91° | 86° | 92° | 89° | 89° | — | — | 86–92° |
| 7d · 2026-09-14 | 88° | 84° | 86° | 90° | 83° | — | — | 83–90° |
| 6d · 2026-09-15 | 87° | 85° | 89° | 90° | 90° | 89° | 90° | 85–90° |
| 5d · 2026-09-16 | 88° | 87° | 89° | 91° | 93° | 90° | 92° | 87–93° |
| 4d · 2026-09-17 | 87° | 87° | 90° | 90° | 93° | 91° | 89° | 87–93° |
| 3d · 2026-09-18 | 87° | 90° | 89° | 90° | 92° | 89° | 91° | 87–92° |
| 2d · 2026-09-19 | 89° | 91° | 85° | 90° | 94° | 89° | 88° | 85–94° |
| 1d · 2026-09-20 | 88° | 90° | 89° | 90° | 95° | 88° | 88° | 88–95° |
| actual | 90° |
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.