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Was the forecast right for San Francisco on Thu Aug 13?

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 Thu Aug 13 high anywhere from 62° to 74°;by the final call, the day before, the field had settled to a median of 65°. The day verified at 66° against the ECMWF IFS analysis — drizzle.

GEM landed closest, off by 0.1°. AIGFS ran 3° warm.

14 days out the models said 62–74; it hit 66. GEM led (off 0.1°F); AIGFS ran 3°F warm.
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What every model said, at every lead

Daily-high calls for Thu Aug 13 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 · 2026-07-29 — 77° — — 81° — — 77–81°
14d · 2026-07-30 69° 67° 62° — 74° — — 62–74°
13d · 2026-07-31 66° 70° 67° — 74° — — 66–74°
12d · 2026-08-01 72° 72° 61° — 68° — — 61–72°
11d · 2026-08-02 74° 72° 64° — 69° — — 64–74°
10d · 2026-08-03 68° 70° 63° — 74° — — 63–74°
9d · 2026-08-04 67° 70° 66° 69° 67° — — 66–70°
8d · 2026-08-05 66° 64° 69° 68° 71° — — 64–71°
7d · 2026-08-06 68° 66° 68° 68° 73° — — 66–73°
6d · 2026-08-07 67° 73° 68° 70° 73° 68° 66° 66–73°
5d · 2026-08-08 66° 73° 71° 68° 71° 69° 68° 66–73°
4d · 2026-08-09 64° 72° 72° 65° 69° 66° 66° 64–72°
3d · 2026-08-10 63° 67° 71° 64° 66° 66° 67° 63–71°
2d · 2026-08-11 64° 67° 65° 64° 67° 64° 66° 64–67°
1d · 2026-08-12 64° 69° 65° 66° 67° 63° 65° 63–69°
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.