Was the forecast right for Boston on Sat Oct 10?
Boston, Massachusetts · daily high temperature in °C · forecasts from each model's archived runs, verified against the BOS observations
14 days out, 4 models put Boston's Sat Oct 10 high anywhere from 11° to 20°;by the final call, the day before, the field had settled to a median of 17°. The day verified at 17° against the BOS observations — cloudy.
ICON landed closest, off by 0.2°. GEM ran 1° warm.
What every model said, at every lead
Daily-high calls for Sat Oct 10 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 Boston scoreboard shows them, labelled.
| Lead | AIFS | AIGFS | ECMWF | GEM | GFS | ICON | UKMO | Range |
|---|---|---|---|---|---|---|---|---|
| 15d · 2026-09-25 | — | 20° | — | — | 16° | — | — | 16–20° |
| 14d · 2026-09-26 | 14° | 20° | 19° | — | 11° | — | — | 11–20° |
| 13d · 2026-09-27 | 17° | 21° | 15° | — | 13° | — | — | 13–21° |
| 12d · 2026-09-28 | 17° | 19° | 12° | — | 15° | — | — | 12–19° |
| 11d · 2026-09-29 | 23° | 15° | 20° | — | 12° | — | — | 12–23° |
| 10d · 2026-09-30 | 24° | 16° | 15° | — | 15° | — | — | 15–24° |
| 9d · 2026-10-01 | 18° | 21° | 20° | 23° | 14° | — | — | 14–23° |
| 8d · 2026-10-02 | 18° | 23° | 20° | 19° | 16° | — | — | 16–23° |
| 7d · 2026-10-03 | 19° | 18° | 17° | 18° | 16° | — | — | 16–19° |
| 6d · 2026-10-04 | 17° | 17° | 19° | 18° | 17° | 23° | 17° | 17–23° |
| 5d · 2026-10-05 | 19° | 17° | 21° | 13° | 16° | 19° | 18° | 13–21° |
| 4d · 2026-10-06 | 19° | 20° | 19° | 13° | 19° | 19° | 19° | 13–20° |
| 3d · 2026-10-07 | 18° | 18° | 17° | 18° | 18° | 16° | 16° | 16–18° |
| 2d · 2026-10-08 | 17° | 17° | 16° | 18° | 17° | 18° | 17° | 16–18° |
| 1d · 2026-10-09 | 17° | 17° | 16° | 19° | 16° | 17° | 16° | 16–19° |
| actual | 17° |
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 Boston — 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 BOS observations. 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.