Boston, Massachusetts Revisions
MILEPOST 1401
Boston's forecast for Monday has moved 8°F colder
61°F in the 20261014T12:00Z run, 53°F in the 20261016T06:00Z — the 2nd-largest revision of the 3 cities on the roster that moved at all. The current run's 10th-to-90th percentile spread at that hour is 6°F.
Successive cycles do not merely refresh a forecast; they leave a trail. For Monday, October 19 at 21Z in Boston, that trail runs from 61.4°F in the 20261014T12:00Z cycle to 53.1°F in the 20261016T06:00Z — a move of -8.3°F across 8 runs.
The change is larger than the run's own 10th-to-90th percentile spread — the guidance did not merely narrow, it moved off its previous position.
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 Monday at 21Z api.weather.city /v1/history (nbm-qmd) |
-8.3 °F | normal 0.0 °F · 2 of 3 8 synoptic cycles |
| 10th-to-90th percentile spread at that hour api.weather.city (nbm-qmd) |
5.8 °F | normal 8.3 °F current run |
- Milepost
- 1401 · laid 2026-10-16T16:25:19Z
- Model
- nbm-qmd · cycle 20261016T06:00Z
- 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
- ca95a8a3029ad2bd679ceb2db8ee89f7e93299532e36fdb249cc8eab544356f8
- Machine
- JSON