Was the forecast right for Boston on Sun Oct 4?
Boston, Massachusetts · daily high temperature in °F · forecasts from each model's archived runs, verified against the BOS observations
14 days out, 4 models put Boston's Sun Oct 4 high anywhere from 59° to 73°;by the final call, the day before, the field had settled to a median of 62°. The day verified at 63° against the BOS observations — drizzle.
ICON landed closest, off by 0.4°.
What every model said, at every lead
Daily-high calls for Sun Oct 4 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 · 2026-09-19 | — | 57° | — | — | 70° | — | — | 57–70° |
| 14d · 2026-09-20 | 59° | 66° | 73° | — | 70° | — | — | 59–73° |
| 13d · 2026-09-21 | 62° | 67° | 73° | — | 58° | — | — | 58–73° |
| 12d · 2026-09-22 | 61° | 62° | 78° | — | 71° | — | — | 61–78° |
| 11d · 2026-09-23 | 67° | 57° | 59° | — | 60° | — | — | 57–67° |
| 10d · 2026-09-24 | 61° | 75° | 66° | — | 70° | — | — | 61–75° |
| 9d · 2026-09-25 | 59° | 69° | 59° | 70° | 71° | — | — | 59–71° |
| 8d · 2026-09-26 | 60° | 68° | 60° | 59° | 59° | — | — | 59–68° |
| 7d · 2026-09-27 | 62° | 63° | 64° | 59° | 56° | — | — | 56–64° |
| 6d · 2026-09-28 | 62° | 59° | 63° | 62° | 66° | 63° | 66° | 59–66° |
| 5d · 2026-09-29 | 64° | 63° | 62° | 63° | 61° | 60° | 63° | 60–64° |
| 4d · 2026-09-30 | 64° | 64° | 63° | 62° | 61° | 60° | 64° | 60–64° |
| 3d · 2026-10-01 | 63° | 64° | 62° | 62° | 62° | 61° | 62° | 61–64° |
| 2d · 2026-10-02 | 62° | 63° | 62° | 64° | 61° | 61° | 63° | 61–64° |
| 1d · 2026-10-03 | 62° | 64° | 62° | 65° | 62° | 63° | 62° | 62–65° |
| actual | 63° |
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.