The National Weather Service kept the alerts churning as a line of severe thunderstorms swept across Massachusetts Saturday with an EF1 tornado confirmed in Holden.

First came the T-storm updates, then the tornado warnings, followed by Hanscom and Logan airports being put on notice.

Boaters were the last to be warned to watch the sky as a line of wind-whipping storms pushed out to sea.

The NWS later announced a radar-confirmed tornado touched down in Holden around 4:07 p.m. — with no injuries reported but “downed trees and scattered debris in the path of the tornado.” An EF1 tornado is classified as a moderate tornado with wind speeds between 86-110 miles per hour, according to multiple reports and the NWS.

The NWS first posted the tornado warning for “east central Worcester County in central Massachusetts, Central Middlesex County in northeastern Massachusetts.” That was for 4 p.m.

The alert warned that “a severe thunderstorm capable of producing a tornado was located over Holden, or near Worcester, moving east at 40 mph” just after 4 p.m. And, in a key addendum, the NWS stated — “Radar indicated rotation.”

The weather service added “Flying debris will be dangerous to those caught without shelter. Mobile homes will be damaged or destroyed. Damage to roofs, windows, and vehicles will occur. Tree damage is likely.”

The storm was near Worcester, Shrewsbury, Holden, Northborough, Clinton, Lancaster, Sterling, West Boylston, Bolton, and Boylston around 410 PM EDT.

Marlborough, Hudson, and Westborough around 4:15 PM EDT. Southborough, Stow, and Harvard around 4:20 PM EDT.
Framingham, Acton, Sudbury, Maynard, and Boxborough around 4:25 PM

At the height of the storms, 2,647 people lost power, according to National Grid’s power outage map. That tally has dropped to 148 customers at 9:30 p.m.