The Spread

Was the forecast right for Phoenix on Fri Aug 7?

Phoenix, Arizona · daily high temperature in °C · forecasts from each model's archived runs, verified against ERA5

11 days out, 4 models put Phoenix's Fri Aug 7 high anywhere from 38° to 40°; by the final call the field had settled to a median of 43°. ERA5 says the day verified at 43° — cloudy.

GEM landed closest, off by 0.1°. ECMWF ran 2° hot.

11 days out the models said 38–40; it hit 43. GEM led (off 0.1°C); ECMWF ran 2°C hot.
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 Fri Aug 7 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 AIFSAIGFSECMWFGEMGFSICONUKMO Range
11d · 2026-07-27 39° 40° 40° 38° 38–40°
10d · 2026-07-28 39° 38° 39° 35° 35–39°
9d · 2026-07-29 41° 42° 37° 38° 37–42°
8d · 2026-07-30 42° 41° 45° 41° 41° 41–45°
7d · 2026-07-31 40° 42° 41° 42° 41° 40–42°
6d · 2026-08-01 40° 41° 41° 43° 40° 45° 40–45°
5d · 2026-08-02 42° 41° 43° 42° 40° 42° 41° 40–43°
4d · 2026-08-03 43° 42° 43° 43° 42° 45° 45° 42–45°
3d · 2026-08-04 43° 42° 46° 45° 43° 45° 44° 42–46°
2d · 2026-08-05 43° 43° 44° 44° 43° 45° 45° 43–45°
1d · 2026-08-06 43° 42° 44° 45° 44° 44° 44° 42–45°
0d · 2026-08-07 43° 43° 45° 43° 43° 43° 43° 43–45°
actual 43°

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 ERA5 reanalysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.