Was the forecast right for St. Louis on Thu Sep 10?
St. Louis, Missouri · daily high temperature in °C · 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 30° to 32°; by the final call the field had settled to a median of 25°. The day verified at 27° against the STL observations, with 3.8 mm of precipitation — thunderstorms.
GEM landed closest, off by 0.2°. AIGFS ran 3° 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 | — | 27° | — | — | 25° | — | — | 25–27° |
| 14d · 2026-08-27 | 21° | 30° | — | — | 31° | — | — | 21–31° |
| 13d · 2026-08-28 | 32° | 31° | 30° | — | 30° | — | — | 30–32° |
| 12d · 2026-08-29 | 32° | 32° | 34° | — | 30° | — | — | 30–34° |
| 11d · 2026-08-30 | 28° | 35° | 26° | — | 37° | — | — | 26–37° |
| 10d · 2026-08-31 | 33° | 32° | 29° | — | 37° | — | — | 29–37° |
| 9d · 2026-09-01 | 35° | 38° | 38° | — | 37° | — | — | 35–38° |
| 8d · 2026-09-02 | 35° | 35° | 28° | 36° | 34° | — | — | 28–36° |
| 7d · 2026-09-03 | 31° | 37° | 36° | 35° | 39° | — | — | 31–39° |
| 6d · 2026-09-04 | 28° | 30° | 32° | 35° | 44° | — | — | 28–44° |
| 5d · 2026-09-05 | 26° | 23° | 31° | 25° | 28° | 28° | 27° | 23–31° |
| 4d · 2026-09-06 | 27° | 26° | 28° | 28° | 28° | 28° | 28° | 26–28° |
| 3d · 2026-09-07 | 26° | 28° | 28° | 25° | 29° | 26° | 30° | 25–30° |
| 2d · 2026-09-08 | 24° | 23° | 27° | 25° | 24° | 26° | 29° | 23–29° |
| 1d · 2026-09-09 | 25° | 24° | 26° | 27° | 26° | 25° | 27° | 24–27° |
| 0d · 2026-09-10 | 25° | 24° | 25° | 27° | 25° | 26° | 25° | 24–27° |
| actual | 27° |
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.