Was the forecast right for St. Louis on Tue Sep 1?
St. Louis, Missouri · daily high temperature in °C · forecasts from each model's archived runs, verified against the STL observations
7 days out, 5 models put St. Louis's Tue Sep 1 high anywhere from 29° to 36°; by the final call the field had settled to a median of 38°. The day verified at 38° against the STL observations — partly cloudy.
ECMWF landed closest, off by 0.0°. GEM ran 2° hot.
What every model said, at every lead
Daily-high calls for Tue Sep 1 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 |
|---|---|---|---|---|---|---|---|---|
| 7d · 2026-08-25 | 29° | 29° | 36° | 34° | 30° | — | — | 29–36° |
| 6d · 2026-08-26 | 36° | 36° | 38° | 36° | 39° | 36° | — | 36–39° |
| 5d · 2026-08-27 | 36° | 34° | 38° | 36° | 40° | 37° | 35° | 34–40° |
| 4d · 2026-08-28 | 36° | 35° | 38° | 36° | 40° | 36° | 35° | 35–40° |
| 3d · 2026-08-29 | 36° | 35° | 39° | 36° | 41° | 37° | 35° | 35–41° |
| 2d · 2026-08-30 | 36° | 36° | 38° | 37° | 40° | 37° | 37° | 36–40° |
| 1d · 2026-08-31 | 37° | 36° | 38° | 40° | 39° | 37° | 37° | 36–40° |
| 0d · 2026-09-01 | 37° | 38° | 38° | 39° | 39° | 37° | 37° | 37–39° |
| actual | 38° |
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.