Was the forecast right for Phoenix on Wed Aug 5?
Phoenix, Arizona · daily high temperature in °F · forecasts from each model's archived runs, verified against the ECMWF IFS analysis
10 days out, 4 models put Phoenix's Wed Aug 5 high anywhere from 103° to 109°;by the final call, the day before, the field had settled to a median of 106°. The day verified at 104° against the ECMWF IFS analysis, with 0.04 in of precipitation — drizzle.
AIFS landed closest, off by 1.8°. GEM ran 4° warm.
What every model said, at every lead
Daily-high calls for Wed Aug 5 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 |
|---|---|---|---|---|---|---|---|---|
| 10d · 2026-07-26 | 103° | 109° | 103° | — | 105° | — | — | 103–109° |
| 9d · 2026-07-27 | 100° | 99° | 107° | 94° | 106° | — | — | 94–107° |
| 8d · 2026-07-28 | 100° | 104° | 109° | 101° | 108° | — | — | 100–109° |
| 7d · 2026-07-29 | 100° | 104° | 105° | 102° | 107° | — | — | 100–107° |
| 6d · 2026-07-30 | 102° | 105° | 105° | 100° | 104° | 108° | 96° | 96–108° |
| 5d · 2026-07-31 | 102° | 106° | 103° | 104° | 108° | 106° | 112° | 102–112° |
| 4d · 2026-08-01 | 104° | 104° | 103° | 107° | 108° | 107° | 113° | 103–113° |
| 3d · 2026-08-02 | 106° | 105° | 107° | 108° | 107° | 109° | 113° | 105–113° |
| 2d · 2026-08-03 | 106° | 106° | 108° | 108° | 107° | 105° | 109° | 105–109° |
| 1d · 2026-08-04 | 106° | 106° | 106° | 108° | 106° | 106° | 108° | 106–108° |
| actual | 104° |
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 ECMWF IFS analysis (temperature_2m_max). 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.