Was the forecast right for St. Louis on Sun Sep 13?
St. Louis, Missouri · daily high temperature in °F · forecasts from each model's archived runs, verified against the STL observations
13 days out, 4 models put St. Louis's Sun Sep 13 high anywhere from 75° to 99°; by the final call the field had settled to a median of 83°. The day verified at 86° against the STL observations — cloudy.
ECMWF landed closest, off by 1.6°. ICON ran 9° cold.
What every model said, at every lead
Daily-high calls for Sun Sep 13 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 St. Louis scoreboard shows them, labelled.
| Lead | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-08-29 | — | 101° | — | — | 99° | — | — | 99–101° |
| 14d · 2026-08-30 | 84° | 81° | — | — | 86° | — | — | 81–86° |
| 13d · 2026-08-31 | 75° | 92° | 84° | — | 99° | — | — | 75–99° |
| 12d · 2026-09-01 | 86° | 78° | 89° | — | 81° | — | — | 78–89° |
| 11d · 2026-09-02 | 87° | 90° | 89° | — | 102° | — | — | 87–102° |
| 10d · 2026-09-03 | 81° | 99° | 75° | — | 104° | — | — | 75–104° |
| 9d · 2026-09-04 | 84° | 82° | 100° | — | 106° | — | — | 82–106° |
| 8d · 2026-09-05 | 87° | 91° | 78° | 82° | 101° | — | — | 78–101° |
| 7d · 2026-09-06 | 86° | 90° | 93° | 88° | 95° | — | — | 86–95° |
| 6d · 2026-09-07 | 88° | 93° | 87° | 90° | 102° | 81° | — | 81–102° |
| 5d · 2026-09-08 | 83° | 80° | 86° | 76° | 84° | 93° | 96° | 76–96° |
| 4d · 2026-09-09 | 82° | 86° | 91° | 89° | 95° | 90° | 94° | 82–95° |
| 3d · 2026-09-10 | 83° | 89° | 86° | 79° | 98° | 89° | 85° | 79–98° |
| 2d · 2026-09-11 | 82° | 88° | 89° | 92° | 93° | 93° | 90° | 82–93° |
| 1d · 2026-09-12 | 82° | 84° | 88° | 77° | 90° | 84° | 84° | 77–90° |
| 0d · 2026-09-13 | 80° | 83° | 84° | 84° | 89° | 77° | 81° | 77–89° |
| actual | 86° |
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 St. Louis — 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 STL observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.