Was the forecast right for Boston on Mon Oct 12?
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 Mon Oct 12 high anywhere from 13° to 18°;by the final call, the day before, the field had settled to a median of 20°. The day verified at 22° against the BOS observations, with 2.5 mm of precipitation — showers.
GEM landed closest, off by 0.8°. AIFS ran 3° cool.
What every model said, at every lead
Daily-high calls for Mon Oct 12 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 · 2026-09-27 | — | 17° | — | — | 17° | — | — | 17–17° |
| 14d · 2026-09-28 | 13° | 18° | 18° | — | 18° | — | — | 13–18° |
| 13d · 2026-09-29 | 16° | 24° | 25° | — | 19° | — | — | 16–25° |
| 12d · 2026-09-30 | 24° | 20° | 23° | — | 19° | — | — | 19–24° |
| 11d · 2026-10-01 | 25° | 24° | 21° | — | 24° | — | — | 21–25° |
| 10d · 2026-10-02 | 24° | 27° | 21° | — | 25° | — | — | 21–27° |
| 9d · 2026-10-03 | 16° | 18° | 21° | 19° | 10° | — | — | 10–21° |
| 8d · 2026-10-04 | 16° | 22° | 25° | 18° | 19° | — | — | 16–25° |
| 7d · 2026-10-05 | 19° | 17° | 20° | 19° | 18° | — | — | 17–20° |
| 6d · 2026-10-06 | 17° | 18° | 18° | 22° | 17° | 16° | — | 16–22° |
| 5d · 2026-10-07 | 17° | 17° | 21° | 17° | 17° | 22° | 17° | 17–22° |
| 4d · 2026-10-08 | 18° | 17° | 17° | 16° | 16° | 21° | 18° | 16–21° |
| 3d · 2026-10-09 | 19° | 19° | 17° | 17° | 17° | 22° | 18° | 17–22° |
| 2d · 2026-10-10 | 19° | 19° | 18° | 19° | 18° | 22° | 21° | 18–22° |
| 1d · 2026-10-11 | 19° | 20° | 20° | 21° | 21° | 20° | 20° | 19–21° |
| actual | 22° |
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.