Was the forecast right for Phoenix on Sun Aug 16?
Phoenix, Arizona · daily high temperature in °F · forecasts from each model's archived runs, verified against the ECMWF IFS analysis
14 days out, 4 models put Phoenix's Sun Aug 16 high anywhere from 94° to 103°;by the final call, the day before, the field had settled to a median of 107°. The day verified at 109° against the ECMWF IFS analysis, with 0.01 in of precipitation — drizzle.
GFS landed closest, off by 0.4°. UKMO ran 7° cool.
What every model said, at every lead
Daily-high calls for Sun Aug 16 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 |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-08-01 | — | 104° | — | — | 104° | — | — | 104–104° |
| 14d · 2026-08-02 | 94° | 97° | 102° | — | 103° | — | — | 94–103° |
| 13d · 2026-08-03 | 105° | 103° | 91° | — | 107° | — | — | 91–107° |
| 12d · 2026-08-04 | 103° | 106° | 99° | — | 106° | — | — | 99–106° |
| 11d · 2026-08-05 | 102° | 102° | 109° | — | 105° | — | — | 102–109° |
| 10d · 2026-08-06 | 98° | 105° | 92° | — | 106° | — | — | 92–106° |
| 9d · 2026-08-07 | 102° | 105° | 108° | 107° | 106° | — | — | 102–108° |
| 8d · 2026-08-08 | 109° | 105° | 109° | 107° | 106° | — | — | 105–109° |
| 7d · 2026-08-09 | 110° | 104° | 110° | 107° | 103° | — | — | 103–110° |
| 6d · 2026-08-10 | 106° | 105° | 108° | 106° | 106° | 107° | 108° | 105–108° |
| 5d · 2026-08-11 | 108° | 103° | 108° | 106° | 103° | 106° | 106° | 103–108° |
| 4d · 2026-08-12 | 108° | 105° | 108° | 104° | 107° | 108° | 106° | 104–108° |
| 3d · 2026-08-13 | 108° | 105° | 110° | 104° | 107° | 109° | 105° | 104–110° |
| 2d · 2026-08-14 | 109° | 106° | 109° | 104° | 106° | 108° | 106° | 104–109° |
| 1d · 2026-08-15 | 108° | 106° | 108° | 106° | 110° | 107° | 102° | 102–110° |
| actual | 109° |
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.