Was the forecast right for Phoenix on Wed Aug 26?
Phoenix, Arizona · daily high temperature in °F · forecasts from each model's archived runs, verified against the PHX observations
6 days out, 6 models put Phoenix's Wed Aug 26 high anywhere from 106° to 115°; by the final call the field had settled to a median of 114°. The day verified at 117° against the PHX observations — cloudy.
ECMWF landed closest, off by 0.5°. GEM ran 6° cold.
What every model said, at every lead
Daily-high calls for Wed Aug 26 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 |
|---|---|---|---|---|---|---|---|---|
| 6d · 2026-08-20 | 110° | 106° | 115° | 110° | 111° | 115° | — | 106–115° |
| 5d · 2026-08-21 | 111° | 108° | 116° | 111° | 111° | 116° | 114° | 108–116° |
| 4d · 2026-08-22 | 113° | 109° | 117° | 108° | 115° | 116° | 114° | 108–117° |
| 3d · 2026-08-23 | 113° | 111° | 116° | 108° | 113° | 114° | 115° | 108–116° |
| 2d · 2026-08-24 | 114° | 112° | 116° | 111° | 114° | 116° | 114° | 111–116° |
| 1d · 2026-08-25 | 114° | 114° | 116° | 111° | 115° | 116° | 114° | 111–116° |
| 0d · 2026-08-26 | 114° | 113° | 116° | 111° | 114° | 113° | 114° | 111–116° |
| actual | 117° |
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 the PHX observations. Archive depth varies by city; receipts exist only for dates the archive watched arrive.