Was the forecast right for Philadelphia on Tue Sep 22?
Philadelphia, Pennsylvania · daily high temperature in °F · forecasts from each model's archived runs, verified against the PHL observations
14 days out, 4 models put Philadelphia's Tue Sep 22 high anywhere from 64° to 73°;by the final call, the day before, the field had settled to a median of 64°. The day verified at 66° against the PHL observations, with 0.5 in of precipitation — showers.
GEM landed closest, off by 0.1°. ICON ran 3° cool.
What every model said, at every lead
Daily-high calls for Tue Sep 22 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 Philadelphia scoreboard shows them, labelled.
| Lead | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-09-07 | — | 80° | — | — | 78° | — | — | 78–80° |
| 14d · 2026-09-08 | 71° | 64° | 70° | — | 73° | — | — | 64–73° |
| 13d · 2026-09-09 | 84° | 66° | 68° | — | 79° | — | — | 66–84° |
| 12d · 2026-09-10 | 67° | 64° | 62° | — | 71° | — | — | 62–71° |
| 11d · 2026-09-11 | 70° | 70° | 84° | — | 72° | — | — | 70–84° |
| 10d · 2026-09-12 | 78° | 68° | 78° | — | 65° | — | — | 65–78° |
| 9d · 2026-09-13 | 71° | 73° | 86° | 80° | 68° | — | — | 68–86° |
| 8d · 2026-09-14 | 64° | 69° | 72° | 70° | 63° | — | — | 63–72° |
| 7d · 2026-09-15 | 67° | 70° | 78° | 68° | 67° | — | — | 67–78° |
| 6d · 2026-09-16 | 66° | 66° | 69° | 69° | 74° | 75° | 72° | 66–75° |
| 5d · 2026-09-17 | 64° | 63° | 68° | 63° | 65° | 67° | 68° | 63–68° |
| 4d · 2026-09-18 | 64° | 62° | 68° | 60° | 61° | 66° | 70° | 60–70° |
| 3d · 2026-09-19 | 65° | 62° | 66° | 64° | 61° | 65° | 71° | 61–71° |
| 2d · 2026-09-20 | 64° | 62° | 65° | 67° | 65° | 66° | 71° | 62–71° |
| 1d · 2026-09-21 | 63° | 64° | 66° | 66° | 63° | 63° | 68° | 63–68° |
| 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 Philadelphia — 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 PHL observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.