The Spread

Was the forecast right for Seattle on Sat Aug 15?

Seattle, Washington · daily high temperature in °F · forecasts from each model's archived runs, verified against the ECMWF IFS analysis

14 days out, 4 models put Seattle's Sat Aug 15 high anywhere from 67° to 80°; by the final call the field had settled to a median of 76°. The ECMWF IFS analysis says the day verified at 77° with 0.01 in of precipitation — drizzle.

GEM landed closest, off by 1.0°. AIFS ran 7° cold.

14 days out the models said 67–80; it hit 77. GEM led (off 1.0°F); AIFS ran 7°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 Sat Aug 15 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 · 2026-07-31 77° 82° 77–82°
14d · 2026-08-01 80° 67° 75° 76° 67–80°
13d · 2026-08-02 78° 91° 72° 76° 72–91°
12d · 2026-08-03 75° 91° 81° 75° 75–91°
11d · 2026-08-04 78° 88° 86° 81° 78–88°
10d · 2026-08-05 81° 69° 88° 84° 69–88°
9d · 2026-08-06 79° 78° 75° 83° 78° 75–83°
8d · 2026-08-07 76° 77° 84° 76° 85° 76–85°
7d · 2026-08-08 75° 76° 82° 76° 89° 75–89°
6d · 2026-08-09 73° 78° 83° 79° 87° 73° 80° 73–87°
5d · 2026-08-10 72° 78° 81° 76° 86° 78° 78° 72–86°
4d · 2026-08-11 74° 79° 81° 76° 86° 78° 78° 74–86°
3d · 2026-08-12 74° 79° 81° 75° 87° 75° 80° 74–87°
2d · 2026-08-13 72° 79° 81° 75° 86° 77° 78° 72–86°
1d · 2026-08-14 70° 76° 80° 78° 76° 75° 79° 70–80°
0d · 2026-08-15 70° 76° 81° 76° 73° 70° 76° 70–81°
actual 77°

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 the ECMWF IFS analysis (temperature_2m_max). Archive depth varies by city; receipts exist only for dates the archive watched arrive.