Was the forecast right for St. Louis on Mon Sep 21?
St. Louis, Missouri · daily high temperature in °F · forecasts from each model's archived runs, verified against the STL observations
14 days out, 4 models put St. Louis's Mon Sep 21 high anywhere from 72° to 87°;by the final call, the day before, the field had settled to a median of 73°. The day verified at 73° against the STL observations, with 0.33 in of precipitation — thunderstorms.
AIFS landed closest, off by 0.0°. GEM ran 4° warm.
What every model said, at every lead
Daily-high calls for Mon Sep 21 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 · 2026-09-06 | — | 61° | — | — | 78° | — | — | 61–78° |
| 14d · 2026-09-07 | 75° | 78° | 72° | — | 87° | — | — | 72–87° |
| 13d · 2026-09-08 | 75° | 69° | 68° | — | 72° | — | — | 68–75° |
| 12d · 2026-09-09 | 91° | 70° | 66° | — | 83° | — | — | 66–91° |
| 11d · 2026-09-10 | 69° | 68° | 68° | — | 69° | — | — | 68–69° |
| 10d · 2026-09-11 | 69° | 75° | 89° | — | 86° | — | — | 69–89° |
| 9d · 2026-09-12 | 83° | 65° | 70° | 79° | 78° | — | — | 65–83° |
| 8d · 2026-09-13 | 95° | 82° | 95° | 97° | 87° | — | — | 82–97° |
| 7d · 2026-09-14 | 71° | 87° | 72° | 77° | 71° | — | — | 71–87° |
| 6d · 2026-09-15 | 84° | 78° | 90° | 82° | 92° | 74° | 71° | 71–92° |
| 5d · 2026-09-16 | 80° | 70° | 83° | 80° | 86° | 79° | 77° | 70–86° |
| 4d · 2026-09-17 | 77° | 77° | 76° | 78° | 88° | 71° | 72° | 71–88° |
| 3d · 2026-09-18 | 76° | 74° | 76° | 79° | 76° | 72° | 70° | 70–79° |
| 2d · 2026-09-19 | 77° | 76° | 76° | 75° | 74° | 72° | 72° | 72–77° |
| 1d · 2026-09-20 | 73° | 73° | 77° | 77° | 72° | 73° | 76° | 72–77° |
| actual | 73° |
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.