Was the forecast right for Phoenix on Mon Aug 24?
Phoenix, Arizona · daily high temperature in °C · forecasts from each model's archived runs, verified against the PHX observations
4 days out, 7 models put Phoenix's Mon Aug 24 high anywhere from 39° to 44°; by the final call the field had settled to a median of 41°. The day verified at 42° against the PHX observations, with 1.0 mm of precipitation — drizzle.
ICON landed closest, off by 0.2°. UKMO ran 3° cold.
What every model said, at every lead
Daily-high calls for Mon Aug 24 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 |
|---|---|---|---|---|---|---|---|---|
| 4d · 2026-08-20 | 40° | 41° | 44° | 42° | 39° | 44° | 43° | 39–44° |
| 3d · 2026-08-21 | 41° | 42° | 44° | 41° | 43° | 43° | 41° | 41–44° |
| 2d · 2026-08-22 | 42° | 41° | 43° | 41° | 41° | 43° | 41° | 41–43° |
| 1d · 2026-08-23 | 41° | 41° | 43° | 41° | 40° | 43° | 43° | 40–43° |
| 0d · 2026-08-24 | 41° | 41° | 43° | 41° | 42° | 42° | 39° | 39–43° |
| actual | 42° |
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.