Was the forecast right for Phoenix on Sun Aug 9?
Phoenix, Arizona · daily high temperature in °F · forecasts from each model's archived runs, verified against ERA5
13 days out, 4 models put Phoenix's Sun Aug 9 high anywhere from 90° to 99°; by the final call the field had settled to a median of 110°. ERA5 says the day verified at 111° — cloudy.
GFS landed closest, off by 0.3°.
What every model said, at every lead
Daily-high calls for Sun Aug 9 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 Phoenix scoreboard shows them, labelled.
| Lead | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 13d · 2026-07-27 | 95° | 96° | 90° | — | 99° | — | — | 90–99° |
| 12d · 2026-07-28 | 101° | 99° | 87° | — | 103° | — | — | 87–103° |
| 11d · 2026-07-29 | 105° | 106° | 107° | — | 101° | — | — | 101–107° |
| 10d · 2026-07-30 | 105° | 102° | 107° | — | 100° | — | — | 100–107° |
| 9d · 2026-07-31 | 100° | 95° | 104° | — | 106° | — | — | 95–106° |
| 8d · 2026-08-01 | 98° | 104° | 103° | 108° | 106° | — | — | 98–108° |
| 7d · 2026-08-02 | 106° | 105° | 110° | 112° | 104° | — | — | 104–112° |
| 6d · 2026-08-03 | 107° | 108° | 102° | 108° | 108° | 113° | — | 102–113° |
| 5d · 2026-08-04 | 109° | 110° | 104° | 112° | 109° | 109° | 104° | 104–112° |
| 4d · 2026-08-05 | 108° | 108° | 110° | 102° | 108° | 111° | 108° | 102–111° |
| 3d · 2026-08-06 | 108° | 108° | 111° | 108° | 109° | 110° | 109° | 108–111° |
| 2d · 2026-08-07 | 109° | 108° | 112° | 109° | 111° | 112° | 109° | 108–112° |
| 1d · 2026-08-08 | 109° | 107° | 113° | 110° | 111° | 114° | 110° | 107–114° |
| 0d · 2026-08-09 | 110° | 109° | 111° | 112° | 111° | 110° | 110° | 109–112° |
| actual | 111° |
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 Phoenix — 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 ERA5 reanalysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.