The Spread

Was the forecast right for Paris on Fri Sep 4?

Paris, Île-de-France Region · daily high temperature in °F · forecasts from each model's archived runs, verified against the LFPB observations

5 days out, 7 models put Paris's Fri Sep 4 high anywhere from 78° to 88°; by the final call the field had settled to a median of 82°. The day verified at 82° against the LFPB observations — cloudy.

GEM landed closest, off by 0.1°. GFS ran 4° hot.

5 days out the models said 78–88; it hit 82. GEM led (off 0.1°F); GFS ran 4°F hot.
The shareable card for this receipt — what this page looks like pasted into a thread.

What every model said, at every lead

Daily-high calls for Fri Sep 4 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 AIFSAIGFSECMWFGEMGFSICONUKMO Range
5d · 2026-08-30 84° 84° 78° 86° 88° 83° 78° 78–88°
4d · 2026-08-31 82° 83° 83° 83° 83° 86° 84° 82–86°
3d · 2026-09-01 81° 83° 84° 88° 89° 79° 82° 79–89°
2d · 2026-09-02 80° 80° 79° 86° 85° 83° 79° 79–86°
1d · 2026-09-03 80° 80° 80° 86° 87° 80° 80° 80–87°
0d · 2026-09-04 82° 81° 84° 82° 86° 81° 80° 80–86°
actual 82°

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.