Was the forecast right for Phoenix on Thu Aug 13?
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 Thu Aug 13 high anywhere from 101° to 107°; by the final call the field had settled to a median of 98°. ERA5 says the day verified at 97° with 0.03 in of precipitation — drizzle.
AIGFS landed closest, off by 1.0°. ICON ran 4° cold.
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 Phoenix scoreboard shows them, labelled.
| Lead | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-07-29 | — | 104° | — | — | 104° | — | — | 104–104° |
| 14d · 2026-07-30 | 90° | 104° | — | — | 105° | — | — | 90–105° |
| 13d · 2026-07-31 | 105° | 101° | 104° | — | 107° | — | — | 101–107° |
| 12d · 2026-08-01 | 96° | 90° | 103° | — | 108° | — | — | 90–108° |
| 11d · 2026-08-02 | 99° | 99° | 103° | — | 105° | — | — | 99–105° |
| 10d · 2026-08-03 | 97° | 106° | 97° | — | 108° | — | — | 97–108° |
| 9d · 2026-08-04 | 94° | 97° | 105° | — | 106° | — | — | 94–106° |
| 8d · 2026-08-05 | 93° | 96° | 89° | 107° | 104° | — | — | 89–107° |
| 7d · 2026-08-06 | 95° | 94° | 105° | 103° | 98° | — | — | 94–105° |
| 6d · 2026-08-07 | 94° | 101° | 102° | 102° | 101° | 96° | — | 94–102° |
| 5d · 2026-08-08 | 99° | 101° | 94° | 101° | 100° | 92° | 98° | 92–101° |
| 4d · 2026-08-09 | 101° | 100° | 97° | 97° | 95° | 92° | 90° | 90–101° |
| 3d · 2026-08-10 | 95° | 100° | 98° | 96° | 97° | 93° | 101° | 93–101° |
| 2d · 2026-08-11 | 97° | 99° | 94° | 98° | 101° | 92° | 99° | 92–101° |
| 1d · 2026-08-12 | 97° | 99° | 95° | 99° | 101° | 92° | 100° | 92–101° |
| 0d · 2026-08-13 | 94° | 98° | 98° | 99° | 99° | 93° | 100° | 93–100° |
| actual | 97° |
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.