The Spread

Was the forecast right for Phoenix on Mon Sep 14?

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

13 days out, 4 models put Phoenix's Mon Sep 14 high anywhere from 92° to 100°; by the final call the field had settled to a median of 100°. The day verified at 105° against the PHX observations — drizzle.

ECMWF landed closest, off by 1.8°. UKMO ran 6° cold.

13 days out the models said 92–100; it hit 105. ECMWF led (off 1.8°F); UKMO ran 6°F 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 Mon Sep 14 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
15d · 2026-08-30 107° 109° 107–109°
14d · 2026-08-31 99° 96° 95° 95–99°
13d · 2026-09-01 92° 92° 94° 100° 92–100°
12d · 2026-09-02 90° 89° 82° 99° 82–99°
11d · 2026-09-03 111° 87° 94° 98° 87–111°
10d · 2026-09-04 98° 94° 83° 102° 83–102°
9d · 2026-09-05 97° 98° 91° 96° 91–98°
8d · 2026-09-06 100° 94° 96° 102° 102° 94–102°
7d · 2026-09-07 97° 102° 91° 106° 100° 91–106°
6d · 2026-09-08 99° 103° 100° 108° 101° 87° 87–108°
5d · 2026-09-09 101° 98° 103° 87° 102° 91° 102° 87–103°
4d · 2026-09-10 100° 96° 100° 104° 103° 92° 105° 92–105°
3d · 2026-09-11 95° 95° 104° 104° 99° 92° 103° 92–104°
2d · 2026-09-12 96° 92° 103° 102° 99° 95° 101° 92–103°
1d · 2026-09-13 97° 95° 102° 102° 104° 98° 102° 95–104°
0d · 2026-09-14 100° 100° 103° 103° 101° 100° 99° 99–103°
actual 105°

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.