Was the forecast right for St. Louis on Fri Sep 18?
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 Fri Sep 18 high anywhere from 71° to 85°; by the final call the field had settled to a median of 95°. The day verified at 98° against the STL observations — partly cloudy.
GFS landed closest, off by 0.2°. AIFS ran 6° cold.
What every model said, at every lead
Daily-high calls for Fri Sep 18 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 · 2026-09-03 | — | 84° | — | — | 88° | — | — | 84–88° |
| 14d · 2026-09-04 | — | 78° | — | — | 104° | — | — | 78–104° |
| 13d · 2026-09-05 | 82° | 71° | 84° | — | 85° | — | — | 71–85° |
| 12d · 2026-09-06 | 72° | 65° | 76° | — | 77° | — | — | 65–77° |
| 11d · 2026-09-07 | 74° | 78° | 74° | — | 78° | — | — | 74–78° |
| 10d · 2026-09-08 | 91° | 90° | 70° | — | 75° | — | — | 70–91° |
| 9d · 2026-09-09 | 74° | 97° | 96° | — | 90° | — | — | 74–97° |
| 8d · 2026-09-10 | 83° | 72° | 74° | 81° | 77° | — | — | 72–83° |
| 7d · 2026-09-11 | 89° | 77° | 88° | 94° | 91° | — | — | 77–94° |
| 6d · 2026-09-12 | 88° | 79° | 97° | 95° | 86° | 92° | — | 79–97° |
| 5d · 2026-09-13 | 89° | 86° | 92° | 92° | 88° | 97° | 92° | 86–97° |
| 4d · 2026-09-14 | 91° | 93° | 95° | 95° | 100° | 83° | 94° | 83–100° |
| 3d · 2026-09-15 | 93° | 89° | 99° | 94° | 99° | 96° | 87° | 87–99° |
| 2d · 2026-09-16 | 94° | 93° | 94° | 96° | 96° | 91° | 94° | 91–96° |
| 1d · 2026-09-17 | 91° | 90° | 94° | 99° | 97° | 91° | 92° | 90–99° |
| 0d · 2026-09-18 | 92° | 95° | 97° | 100° | 98° | 93° | 95° | 92–100° |
| actual | 98° |
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.