The Spread

Was the forecast right for San Francisco on Tue Aug 25?

San Francisco, California · daily high temperature in °C · forecasts from each model's archived runs, verified against the SFOC1 observations

3 days out, 7 models put San Francisco's Tue Aug 25 high anywhere from 18° to 22°; by the final call the field had settled to a median of 21°. The day verified at 21° against the SFOC1 observations — cloudy.

GFS landed closest, off by 0.6°. ICON ran 3° cold.

3 days out the models said 18–22; it hit 21. GFS led (off 0.6°C); ICON ran 3°C cold.
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 Tue Aug 25 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 San Francisco scoreboard shows them, labelled.

Lead AIFSAIGFSECMWFGEMGFSICONUKMO Range
3d · 2026-08-22 22° 22° 19° 18° 20° 18° 22° 18–22°
2d · 2026-08-23 22° 23° 20° 18° 21° 19° 24° 18–24°
1d · 2026-08-24 22° 23° 19° 19° 21° 19° 24° 19–24°
0d · 2026-08-25 22° 24° 20° 19° 21° 18° 22° 18–24°
actual 21°

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 San Francisco — 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 SFOC1 observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.