Was the forecast right for Paris on Thu Sep 17?
Paris, Île-de-France Region · daily high temperature in °F · forecasts from each model's archived runs, verified against the LFPB observations
14 days out, 4 models put Paris's Thu Sep 17 high anywhere from 57° to 92°; by the final call the field had settled to a median of 71°. The day verified at 72° against the LFPB observations — drizzle.
ECMWF landed closest, off by 0.3°. GFS ran 2° hot.
What every model said, at every lead
Daily-high calls for Thu Sep 17 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 Paris scoreboard shows them, labelled.
| Lead | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-09-02 | — | 60° | — | — | 80° | — | — | 60–80° |
| 14d · 2026-09-03 | 67° | 57° | 66° | — | 92° | — | — | 57–92° |
| 13d · 2026-09-04 | 72° | 63° | 70° | — | 70° | — | — | 63–72° |
| 12d · 2026-09-05 | 67° | 77° | 66° | — | 78° | — | — | 66–78° |
| 11d · 2026-09-06 | 65° | 77° | 70° | — | 69° | — | — | 65–77° |
| 10d · 2026-09-07 | 65° | 66° | 65° | — | 70° | — | — | 65–70° |
| 9d · 2026-09-08 | 61° | 68° | 68° | 68° | 68° | — | — | 61–68° |
| 8d · 2026-09-09 | 68° | 64° | 68° | 66° | 92° | — | — | 64–92° |
| 7d · 2026-09-10 | 66° | 68° | 62° | 69° | 71° | — | — | 62–71° |
| 6d · 2026-09-11 | 66° | 66° | 70° | 70° | 70° | 72° | 69° | 66–72° |
| 5d · 2026-09-12 | 68° | 67° | 67° | 62° | 70° | 68° | 70° | 62–70° |
| 4d · 2026-09-13 | 68° | 67° | 66° | 69° | 70° | 66° | 68° | 66–70° |
| 3d · 2026-09-14 | 69° | 69° | 68° | 70° | 70° | 70° | 70° | 68–70° |
| 2d · 2026-09-15 | 69° | 69° | 69° | 71° | 73° | 69° | 68° | 68–73° |
| 1d · 2026-09-16 | 70° | 70° | 70° | 73° | 74° | 70° | 70° | 70–74° |
| 0d · 2026-09-17 | 70° | 70° | 71° | 73° | 74° | 71° | 71° | 70–74° |
| actual | 72° |
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 Paris — 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 LFPB observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.