Was the forecast right for San Francisco on Mon Sep 7?
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 Mon Sep 7 high anywhere from 69° to 96°; by the final call the field had settled to a median of 78°. The day verified at 81° against the SFOC1 observations — partly cloudy.
GFS landed closest, off by 0.5°. GEM ran 7° cold.
What every model said, at every lead
Daily-high calls for Mon Sep 7 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 · 2026-08-23 | — | 69° | — | — | 66° | — | — | 66–69° |
| 14d · 2026-08-24 | 64° | 69° | — | — | 76° | — | — | 64–76° |
| 13d · 2026-08-25 | 72° | 96° | 69° | — | 74° | — | — | 69–96° |
| 12d · 2026-08-26 | 66° | 72° | 65° | — | 67° | — | — | 65–72° |
| 11d · 2026-08-27 | 84° | 68° | 69° | — | 78° | — | — | 68–84° |
| 10d · 2026-08-28 | 72° | 83° | 68° | — | 68° | — | — | 68–83° |
| 9d · 2026-08-29 | 78° | 78° | 72° | — | 78° | — | — | 72–78° |
| 8d · 2026-08-30 | 70° | 70° | 68° | 70° | 61° | — | — | 61–70° |
| 7d · 2026-08-31 | 79° | 86° | 80° | 69° | 69° | — | — | 69–86° |
| 6d · 2026-09-01 | 74° | 68° | 67° | 66° | 74° | 78° | — | 66–78° |
| 5d · 2026-09-02 | 75° | 74° | 72° | 68° | 72° | 65° | 82° | 65–82° |
| 4d · 2026-09-03 | 76° | 77° | 71° | 71° | 71° | 67° | 76° | 67–77° |
| 3d · 2026-09-04 | 78° | 78° | 74° | 71° | 78° | 70° | 81° | 70–81° |
| 2d · 2026-09-05 | 79° | 80° | 76° | 72° | 78° | 75° | 85° | 72–85° |
| 1d · 2026-09-06 | 78° | 81° | 76° | 74° | 78° | 76° | 79° | 74–81° |
| 0d · 2026-09-07 | 78° | 79° | 77° | 74° | 80° | 75° | 83° | 74–83° |
| actual | 81° |
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.