Was the forecast right for St. Louis on Mon Sep 7?
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 Mon Sep 7 high anywhere from 74° to 100°;by the final call, the day before, the field had settled to a median of 86°. The day verified at 87° against the STL observations — cloudy.
ECMWF landed closest, off by 0.5°. GEM ran 5° warm.
What every model said, at every lead
Daily-high calls for Mon Sep 7 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 |
|---|---|---|---|---|---|---|---|---|
| 13d · 2026-08-25 | 74° | 78° | 80° | — | 100° | — | — | 74–100° |
| 12d · 2026-08-26 | 79° | 92° | 97° | — | 90° | — | — | 79–97° |
| 11d · 2026-08-27 | 90° | 74° | 96° | — | 103° | — | — | 74–103° |
| 10d · 2026-08-28 | 81° | 83° | 97° | — | 105° | — | — | 81–105° |
| 9d · 2026-08-29 | 90° | 81° | 96° | 90° | 89° | — | — | 81–96° |
| 8d · 2026-08-30 | 84° | 85° | 94° | 90° | 105° | — | — | 84–105° |
| 7d · 2026-08-31 | 86° | 87° | 84° | 89° | 92° | — | — | 84–92° |
| 6d · 2026-09-01 | 87° | 91° | 90° | 94° | 94° | 89° | 97° | 87–97° |
| 5d · 2026-09-02 | 87° | 90° | 90° | 87° | 99° | 93° | 96° | 87–99° |
| 4d · 2026-09-03 | 84° | 88° | 90° | 90° | 92° | 90° | 86° | 84–92° |
| 3d · 2026-09-04 | 85° | 87° | 87° | 87° | 93° | 87° | 91° | 85–93° |
| 2d · 2026-09-05 | 86° | 86° | 87° | 87° | 90° | 87° | 87° | 86–90° |
| 1d · 2026-09-06 | 85° | 85° | 86° | 92° | 91° | 86° | 86° | 85–92° |
| actual | 87° |
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. The actual values are the ones in hand when this receipt was settled, usually 2 days after the date; a correction published after that is not carried into it. Archive depth varies by city; receipts exist only for dates the archive watched arrive.