Was the forecast right for Phoenix on Sun Aug 23?

Phoenix, Arizona · daily high temperature in °C · forecasts from each model's archived runs, verified against the PHX observations

3 days out, 7 models put Phoenix's Sun Aug 23 high anywhere from 39° to 45°; by the final call the field had settled to a median of 44°. The day verified at 45° against the PHX observations — drizzle.

ICON landed closest, off by 0.1°. AIFS ran 3° cold.

3 days out the models said 39–45; it hit 45. ICON led (off 0.1°C); AIFS ran 3°C cold. — The shareable card for this receipt — what this page looks like pasted into a thread.

What every model said, at every lead

Daily-high calls for Sun Aug 23 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
3d · 2026-08-20	40°	42°	44°	39°	44°	45°	41°	39–45°
2d · 2026-08-21	42°	42°	45°	40°	44°	45°	41°	40–45°
1d · 2026-08-22	42°	42°	45°	41°	44°	45°	44°	41–45°
0d · 2026-08-23	42°	43°	46°	42°	45°	45°	44°	42–46°
actual								45°

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.