Was the forecast right for San Francisco on Sun Sep 6?
San Francisco, California · daily high temperature in °F · forecasts from each model's archived runs, verified against the SFOC1 observations
14 days out, 4 models put San Francisco's Sun Sep 6 high anywhere from 67° to 80°;by the final call, the day before, the field had settled to a median of 67°. The day verified at 69° against the SFOC1 observations — clear.
UKMO landed closest, off by 0.1°. GEM ran 5° cool.
What every model said, at every lead
Daily-high calls for Sun Sep 6 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 | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-08-22 | — | 74° | — | — | 68° | — | — | 68–74° |
| 14d · 2026-08-23 | 70° | 79° | 67° | — | 80° | — | — | 67–80° |
| 13d · 2026-08-24 | 73° | 72° | 64° | — | 72° | — | — | 64–73° |
| 12d · 2026-08-25 | 67° | 71° | 66° | — | 66° | — | — | 66–71° |
| 11d · 2026-08-26 | 67° | 63° | 63° | — | 76° | — | — | 63–76° |
| 10d · 2026-08-27 | 78° | 69° | 69° | — | 67° | — | — | 67–78° |
| 9d · 2026-08-28 | 77° | 80° | 69° | 68° | 64° | — | — | 64–80° |
| 8d · 2026-08-29 | 68° | 70° | 67° | 65° | 73° | — | — | 65–73° |
| 7d · 2026-08-30 | 67° | 72° | 64° | 67° | 80° | — | — | 64–80° |
| 6d · 2026-08-31 | 67° | 69° | 66° | 65° | 74° | 73° | 73° | 65–74° |
| 5d · 2026-09-01 | 68° | 68° | 66° | 64° | 69° | 63° | 69° | 63–69° |
| 4d · 2026-09-02 | 68° | 68° | 65° | 64° | 66° | 61° | 72° | 61–72° |
| 3d · 2026-09-03 | 67° | 67° | 65° | 64° | 68° | 63° | 68° | 63–68° |
| 2d · 2026-09-04 | 68° | 68° | 64° | 64° | 66° | 62° | 70° | 62–70° |
| 1d · 2026-09-05 | 69° | 71° | 66° | 64° | 67° | 65° | 69° | 64–71° |
| actual | 69° |
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. 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.