The Spread

Was the forecast right for Seattle on Sat Aug 1?

Seattle, Washington · daily high temperature · forecasts from each model's archived runs, verified against ERA5

14 days out, 4 models put Seattle's Sat Aug 1 high anywhere from 71° to 83°; by the final call the field had settled to a median of 71°. ERA5 says the day verified at 73° with 0.04 in of precipitation — drizzle.

GEM landed closest, off by 0.7°. AIFS ran 4° cold.

14 days out the models said 71–83; it hit 73. GEM led (off 0.7°); AIFS ran 4° 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 Sat Aug 1 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 Seattle scoreboard shows them, labelled.

Lead AIFSAIGFSECMWFGEMGFSICONUKMO Range
15d · 2026-07-17 74° 85° 74–85°
14d · 2026-07-18 71° 81° 72° 83° 71–83°
13d · 2026-07-19 72° 76° 81° 76° 72–81°
12d · 2026-07-20 68° 81° 76° 83° 68–83°
11d · 2026-07-21 77° 74° 73° 75° 73–77°
10d · 2026-07-22 76° 68° 79° 77° 68–79°
9d · 2026-07-23 74° 74° 80° 72° 78° 72–80°
8d · 2026-07-24 69° 73° 77° 71° 83° 69–83°
7d · 2026-07-25 67° 74° 72° 69° 71° 67–74°
6d · 2026-07-26 68° 71° 72° 72° 73° 71° 75° 68–75°
5d · 2026-07-27 68° 71° 74° 70° 77° 73° 74° 68–77°
4d · 2026-07-28 68° 72° 71° 71° 76° 70° 70° 68–76°
3d · 2026-07-29 70° 71° 72° 70° 72° 72° 68° 68–72°
2d · 2026-07-30 70° 71° 71° 70° 77° 72° 70° 70–77°
1d · 2026-07-31 69° 71° 72° 72° 68° 72° 71° 68–72°
0d · 2026-08-01 70° 71° 72° 74° 71° 71° 73° 70–74°
actual 73°

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 Seattle — 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.