The Spread Maps Request an invite

Was the forecast right for San Francisco on Wed Aug 12?

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

14 days out, 4 models put San Francisco's Wed Aug 12 high anywhere from 66° to 78°;by the final call, the day before, the field had settled to a median of 69°. The day verified at 66° against the ECMWF IFS analysis — cloudy.

GEM landed closest, off by 0.7°. AIGFS ran 5° warm.

14 days out the models said 66–78; it hit 66. GEM led (off 0.7°F); AIGFS ran 5°F warm.
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 Wed Aug 12 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 · 2026-07-28 — 73° — — 68° — — 68–73°
14d · 2026-07-29 66° 75° 69° — 78° — — 66–78°
13d · 2026-07-30 65° 68° 62° — 76° — — 62–76°
12d · 2026-07-31 68° 68° 68° — 70° — — 68–70°
11d · 2026-08-01 68° 73° 60° — 72° — — 60–73°
10d · 2026-08-02 69° 68° 65° — 73° — — 65–73°
9d · 2026-08-03 68° 75° 64° 66° 72° — — 64–75°
8d · 2026-08-04 70° 68° 65° 68° 67° — — 65–70°
7d · 2026-08-05 67° 67° 68° 69° 73° — — 67–73°
6d · 2026-08-06 69° 70° 69° 69° 74° 65° 68° 65–74°
5d · 2026-08-07 68° 72° 72° 70° 74° 66° 70° 66–74°
4d · 2026-08-08 68° 73° 71° 70° 72° 66° 69° 66–73°
3d · 2026-08-09 67° 72° 69° 69° 71° 66° 68° 66–72°
2d · 2026-08-10 67° 70° 71° 68° 70° 65° 68° 65–71°
1d · 2026-08-11 67° 71° 70° 67° 69° 65° 69° 65–71°
actual 66°

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 ECMWF IFS analysis (temperature_2m_max). The actual values are the ones in hand when this receipt was settled, usually 2 days after the date; a correction published after that is not carried into it. Archive depth varies by city; receipts exist only for dates the archive watched arrive.