Was the forecast right for Boston on Sun Oct 11?
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 Sun Oct 11 high anywhere from 12° to 15°;by the final call, the day before, the field had settled to a median of 16°. The day verified at 16° against the BOS observations, with 36.6 mm of precipitation — showers.
ECMWF landed closest, off by 0.2°. UKMO ran 2° warm.
What every model said, at every lead
Daily-high calls for Sun Oct 11 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 · 2026-09-26 | — | 18° | — | — | 10° | — | — | 10–18° |
| 14d · 2026-09-27 | 15° | 12° | 14° | — | 15° | — | — | 12–15° |
| 13d · 2026-09-28 | 21° | 21° | 16° | — | 14° | — | — | 14–21° |
| 12d · 2026-09-29 | 24° | 17° | 23° | — | 18° | — | — | 17–24° |
| 11d · 2026-09-30 | 25° | 17° | 22° | — | 20° | — | — | 17–25° |
| 10d · 2026-10-01 | 23° | 24° | 22° | — | 12° | — | — | 12–24° |
| 9d · 2026-10-02 | 21° | 27° | 24° | 22° | 17° | — | — | 17–27° |
| 8d · 2026-10-03 | 21° | 14° | 17° | 20° | 14° | — | — | 14–21° |
| 7d · 2026-10-04 | 21° | 16° | 19° | 18° | 16° | — | — | 16–21° |
| 6d · 2026-10-05 | 21° | 18° | 23° | 16° | 19° | 20° | 20° | 16–23° |
| 5d · 2026-10-06 | 18° | 22° | 20° | 18° | 22° | 18° | 21° | 18–22° |
| 4d · 2026-10-07 | 17° | 20° | 20° | 19° | 20° | 19° | 18° | 17–20° |
| 3d · 2026-10-08 | 15° | 17° | 17° | 17° | 18° | 18° | 17° | 15–18° |
| 2d · 2026-10-09 | 16° | 17° | 17° | 18° | 17° | 17° | 16° | 16–18° |
| 1d · 2026-10-10 | 14° | 16° | 15° | 16° | 16° | 15° | 18° | 14–18° |
| actual | 16° |
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.