Was the forecast right for St. Louis on Thu Sep 3?
St. Louis, Missouri · daily high temperature in °F · forecasts from each model's archived runs, verified against the STL observations
9 days out, 5 models put St. Louis's Thu Sep 3 high anywhere from 94° to 103°;by the final call, the day before, the field had settled to a median of 99°. The day verified at 99° against the STL observations — drizzle.
ICON landed closest, off by 0.0°. GFS ran 4° warm.
What every model said, at every lead
Daily-high calls for Thu Sep 3 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 |
|---|---|---|---|---|---|---|---|---|
| 9d · 2026-08-25 | 99° | 101° | 95° | 94° | 103° | — | — | 94–103° |
| 8d · 2026-08-26 | 93° | 98° | 100° | 98° | 106° | — | — | 93–106° |
| 7d · 2026-08-27 | 95° | 98° | 90° | 97° | 107° | — | — | 90–107° |
| 6d · 2026-08-28 | 93° | 96° | 95° | 95° | 106° | 99° | 95° | 93–106° |
| 5d · 2026-08-29 | 98° | 95° | 102° | 97° | 105° | 102° | 97° | 95–105° |
| 4d · 2026-08-30 | 97° | 96° | 100° | 99° | 103° | 101° | 97° | 96–103° |
| 3d · 2026-08-31 | 98° | 97° | 100° | 99° | 103° | 100° | 97° | 97–103° |
| 2d · 2026-09-01 | 98° | 98° | 98° | 98° | 103° | 99° | 96° | 96–103° |
| 1d · 2026-09-02 | 98° | 99° | 98° | 101° | 103° | 99° | 96° | 96–103° |
| actual | 99° |
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.