The Spread

Was the forecast right for San Francisco on Tue Sep 8?

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

13 days out, 4 models put San Francisco's Tue Sep 8 high anywhere from 67° to 71°; by the final call the field had settled to a median of 84°. The day verified at 85° against the SFOC1 observations — cloudy.

GFS landed closest, off by 0.4°. UKMO ran 7° hot.

13 days out the models said 67–71; it hit 85. GFS led (off 0.4°F); UKMO ran 7°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 Tue Sep 8 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
15d · 2026-08-24 69° 67° 67–69°
14d · 2026-08-25 71° 71° 65° 65–71°
13d · 2026-08-26 71° 67° 69° 70° 67–71°
12d · 2026-08-27 71° 74° 67° 76° 67–76°
11d · 2026-08-28 75° 89° 64° 70° 64–89°
10d · 2026-08-29 73° 79° 68° 84° 68–84°
9d · 2026-08-30 72° 73° 71° 72° 71–73°
8d · 2026-08-31 74° 90° 82° 65° 74° 65–90°
7d · 2026-09-01 70° 79° 68° 66° 84° 66–84°
6d · 2026-09-02 76° 81° 67° 65° 75° 66° 65–81°
5d · 2026-09-03 75° 72° 66° 67° 67° 68° 83° 66–83°
4d · 2026-09-04 84° 80° 75° 71° 71° 65° 78° 65–84°
3d · 2026-09-05 86° 85° 78° 74° 79° 84° 88° 74–88°
2d · 2026-09-06 85° 86° 80° 76° 80° 77° 81° 76–86°
1d · 2026-09-07 85° 86° 79° 77° 82° 75° 91° 75–91°
0d · 2026-09-08 84° 86° 81° 79° 85° 79° 92° 79–92°
actual 85°

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.