Boston, Massachusetts Revisions
MILEPOST 1507
Boston's forecast for Sunday has moved 12°F colder
50°F in the 20261025T12:00Z run, 38°F in the 20261027T06:00Z — the 2nd-largest revision of the 8 cities on the roster that moved at all. The current run's 10th-to-90th percentile spread at that hour is 16°F.
Successive cycles do not merely refresh a forecast; they leave a trail. For Sunday, November 1 at 12Z in Boston, that trail runs from 50.3°F in the 20261025T12:00Z cycle to 37.9°F in the 20261027T06:00Z — a move of -12.4°F across 8 runs.
The change is about half the run's 10th-to-90th percentile spread, so the earlier forecast is still inside the current range of outcomes.
Model NBM-QMD, via api.weather.city /v1/history. Percentiles are the same run's own.
The numbers in this piece, with what they are measured against
| forecast revision for Sunday at 12Z api.weather.city /v1/history (nbm-qmd) |
-12.4 °F | normal 0.0 °F · 2 of 8 8 synoptic cycles |
| 10th-to-90th percentile spread at that hour api.weather.city (nbm-qmd) |
16.2 °F | normal 12.4 °F current run |
- Milepost
- 1507 · laid 2026-10-27T16:25:25Z
- Model
- nbm-qmd · cycle 20261027T06:00Z
- Desk
- revision v1
- Method
- the same valid time read from successive synoptic cycles; the move is last run minus first run
- Source
- https://api.weather.city/v1/history
- Digest
- 96b7f9a1d16e00e63d0e8549b1e9e376520099886c858254397d5f2b69dd4452
- Machine
- JSON