The Spread

Was the forecast right for New York on Tue Aug 18?

New York, New York · daily high temperature in °C · forecasts from each model's archived runs, verified against the ECMWF IFS analysis

13 days out, 4 models put New York's Tue Aug 18 high anywhere from 27° to 30°; by the final call the field had settled to a median of 29°. The day verified at 29° against the ECMWF IFS analysis, with 4.3 mm of precipitation — drizzle.

ICON landed closest, off by 0.2°. GEM ran 2° hot.

13 days out the models said 27–30; it hit 29. ICON led (off 0.2°C); GEM 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 Tue Aug 18 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 New York scoreboard shows them, labelled.

Lead AIFSAIGFSECMWFGEMGFSICONUKMO Range
15d · 2026-08-03 25° 28° 25–28°
14d · 2026-08-04 25° 25° 27° 25–27°
13d · 2026-08-05 27° 30° 28° 28° 27–30°
12d · 2026-08-06 26° 30° 32° 25° 25–32°
11d · 2026-08-07 22° 28° 26° 28° 22–28°
10d · 2026-08-08 28° 30° 26° 21° 21–30°
9d · 2026-08-09 28° 27° 29° 28° 27–29°
8d · 2026-08-10 29° 28° 27° 29° 27° 27–29°
7d · 2026-08-11 30° 29° 31° 28° 28° 28–31°
6d · 2026-08-12 26° 27° 29° 28° 28° 26° 26–29°
5d · 2026-08-13 27° 28° 27° 29° 28° 29° 31° 27–31°
4d · 2026-08-14 28° 29° 29° 28° 29° 30° 31° 28–31°
3d · 2026-08-15 29° 28° 31° 27° 31° 29° 31° 27–31°
2d · 2026-08-16 29° 29° 30° 29° 30° 31° 32° 29–32°
1d · 2026-08-17 29° 30° 29° 31° 31° 28° 31° 28–31°
0d · 2026-08-18 28° 30° 29° 31° 29° 28° 29° 28–31°
actual 29°

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 New York — 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.