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Was the forecast right for Charlotte on Mon Aug 17?

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

14 days out, 4 models put Charlotte's Mon Aug 17 high anywhere from 24° to 35°;by the final call, the day before, the field had settled to a median of 37°. The day verified at 36° against the ECMWF IFS analysis, with 0.3 mm of precipitation — drizzle.

AIFS landed closest, off by 0.1°. GEM ran 3° warm.

14 days out the models said 24–35; it hit 36. AIFS led (off 0.1°C); GEM ran 3°C warm.
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 Aug 17 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 Charlotte scoreboard shows them, labelled.

Lead AIFSAIGFSECMWFGEMGFSICONUKMO Range
15d · 2026-08-02 — 33° — — 24° — — 24–33°
14d · 2026-08-03 24° 28° 30° — 35° — — 24–35°
13d · 2026-08-04 30° 30° 25° — 20° — — 20–30°
12d · 2026-08-05 36° 30° 34° — 39° — — 30–39°
11d · 2026-08-06 35° 28° 28° — 36° — — 28–36°
10d · 2026-08-07 35° 36° 34° — 35° — — 34–36°
9d · 2026-08-08 35° 36° 36° 30° 30° — — 30–36°
8d · 2026-08-09 33° 37° 34° 31° 39° — — 31–39°
7d · 2026-08-10 35° 36° 39° 33° 39° — — 33–39°
6d · 2026-08-11 36° 36° 37° 34° 40° 39° 36° 34–40°
5d · 2026-08-12 36° 37° 39° 35° 38° 38° 36° 35–39°
4d · 2026-08-13 36° 36° 40° 33° 40° 36° 36° 33–40°
3d · 2026-08-14 36° 37° 39° 35° 40° 36° 36° 35–40°
2d · 2026-08-15 36° 37° 36° 36° 40° 35° 36° 35–40°
1d · 2026-08-16 36° 37° 36° 39° 38° 37° 36° 36–39°
actual 36°

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 Charlotte — 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). The actual values are the ones in hand when this receipt was settled, usually 2 days after the date; a correction published after that is not carried into it. Archive depth varies by city; receipts exist only for dates the archive watched arrive.