Was the forecast right for Phoenix on Mon Aug 24?
Phoenix, Arizona · daily high temperature in °F · forecasts from each model's archived runs, verified against the PHX observations
5 days out, 7 models put Phoenix's Mon Aug 24 high anywhere from 103° to 112°;by the final call, the day before, the field had settled to a median of 108°. The day verified at 108° against the PHX observations, with 0.04 in of precipitation — drizzle.
GFS landed closest, off by 0.5°. GEM ran 8° cool.
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 |
|---|---|---|---|---|---|---|---|---|
| 5d · 2026-08-19 | 103° | 107° | 112° | 105° | 104° | 112° | 112° | 103–112° |
| 4d · 2026-08-20 | 104° | 107° | 111° | 108° | 106° | 110° | 110° | 104–111° |
| 3d · 2026-08-21 | 106° | 106° | 110° | 105° | 108° | 108° | 102° | 102–110° |
| 2d · 2026-08-22 | 106° | 104° | 109° | 104° | 109° | 109° | 110° | 104–110° |
| 1d · 2026-08-23 | 106° | 106° | 109° | 100° | 108° | 108° | 109° | 100–109° |
| actual | 108° |
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. The actual values are the ones in hand when this receipt was settled, usually 2 days after the date; a correction published after that is not carried into it. Archive depth varies by city; receipts exist only for dates the archive watched arrive.