Boston, Massachusetts Revisions
MILEPOST 1450
Boston's forecast for Thursday has moved 8°F colder
45°F in the 20261018T18:00Z run, 37°F in the 20261020T12:00Z — the 3rd-largest revision of the 9 cities on the roster that moved at all. The current run's 10th-to-90th percentile spread at that hour is 14°F.
Successive cycles do not merely refresh a forecast; they leave a trail. For Thursday, October 29 at 12Z in Boston, that trail runs from 44.9°F in the 20261018T18:00Z cycle to 37.1°F in the 20261020T12:00Z — a move of -7.7°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 Thursday at 12Z api.weather.city /v1/history (nbm-qmd) |
-7.7 °F | normal 0.0 °F · 3 of 9 8 synoptic cycles |
| 10th-to-90th percentile spread at that hour api.weather.city (nbm-qmd) |
13.9 °F | normal 7.7 °F current run |
- Milepost
- 1450 · laid 2026-10-20T22:25:19Z
- Model
- nbm-qmd · cycle 20261020T12:00Z
- 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
- 21ee47f74e7d6915217e1807d2d30cf9d4ee88f96ef13f8c072ba8f18d929f20
- Machine
- JSON