Was the forecast right for St. Louis on Thu Sep 10?
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 Thu Sep 10 high anywhere from 85° to 89°; by the final call the field had settled to a median of 78°. The day verified at 80° against the STL observations, with 0.15 in of precipitation — thunderstorms.
GEM landed closest, off by 0.3°. AIGFS ran 5° cold.
What every model said, at every lead
Daily-high calls for Thu Sep 10 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 · 2026-08-26 | — | 80° | — | — | 77° | — | — | 77–80° |
| 14d · 2026-08-27 | 70° | 86° | — | — | 88° | — | — | 70–88° |
| 13d · 2026-08-28 | 89° | 88° | 87° | — | 85° | — | — | 85–89° |
| 12d · 2026-08-29 | 89° | 90° | 93° | — | 86° | — | — | 86–93° |
| 11d · 2026-08-30 | 82° | 96° | 80° | — | 98° | — | — | 80–98° |
| 10d · 2026-08-31 | 92° | 89° | 85° | — | 99° | — | — | 85–99° |
| 9d · 2026-09-01 | 95° | 101° | 100° | — | 99° | — | — | 95–101° |
| 8d · 2026-09-02 | 94° | 95° | 82° | 97° | 94° | — | — | 82–97° |
| 7d · 2026-09-03 | 88° | 99° | 97° | 95° | 103° | — | — | 88–103° |
| 6d · 2026-09-04 | 82° | 87° | 90° | 95° | 111° | — | — | 82–111° |
| 5d · 2026-09-05 | 80° | 73° | 89° | 77° | 82° | 83° | 81° | 73–89° |
| 4d · 2026-09-06 | 80° | 79° | 83° | 83° | 82° | 82° | 83° | 79–83° |
| 3d · 2026-09-07 | 79° | 82° | 83° | 76° | 84° | 79° | 86° | 76–86° |
| 2d · 2026-09-08 | 76° | 74° | 81° | 76° | 76° | 78° | 84° | 74–84° |
| 1d · 2026-09-09 | 76° | 74° | 80° | 81° | 78° | 78° | 81° | 74–81° |
| 0d · 2026-09-10 | 78° | 75° | 77° | 80° | 77° | 78° | 78° | 75–80° |
| actual | 80° |
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.