UPDATED: Large Storms Approaching, Hail, Isolated Tornadoes Possible

3 p.m.

There are reports coming in that severe thunderstorms have begun in western Massachusetts with cloud tops near 50,000 feet and a hail core reaching 30,000 feet. These are severe cells headed across the state in an easterly direction.

The NWS warns scattered thunderstorms will continue to intensify the course of the afternoon. It states that "these strong to severe thunderstorms should impact Eastern Massachusetts and Rhode Island primarily between 4 and 7 p.m. The main threats from these possible severe thunderstorms will be from large hail and damaging straight-line winds." Isolated tornadoes are also possible through 8 p.m.

The NWS offers the following advice in the event of a tornado:

• The safest place to be is an underground shelter, basement, or safe room.
• If no underground shelter or safe room is available, a small, windowless interior room or hallway on the lowest level of a sturdy building is the safest alternative.
• Mobile homes are not safe during tornadoes. Abandon mobile homes and go to the nearest sturdy building or shelter immediately.
• If you are caught outdoors, seek shelter in a basement, shelter or sturdy building.
• If you cannot quickly walk to a shelter, immediately get into a vehicle, buckle your seat belt and try to drive to the closest sturdy shelter.
• If flying debris occurs while you are driving, pull over and park. Now you have the following options as a last resort: Stay in your vehicle with the seat belt on. Put your head down below the windows, covering with your hands and a blanket if possible. If you can safely get noticeably lower than the level of the roadway, exit your car, and lie in that area, covering your head with your hands.
• Your choice should be driven by your specific circumstances

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A tornado watch has been issued for a large portion of the Atlantic North East this afternoon. Marlborough is among the areas that could be potentially affected, as is the majority of Middlesex and Worcester counties. 

The watch area stretches from southeastern Pennsylvania to Maine until 8 p.m.

There is a chance of tornadoes, hail of up to two inches in diameter, thunderstorms, wind gusts up to 70 mph and lightning.

"A cold front will approach from New York State this afternoon," said a statement from the National Weather Service. "There will be a low probability of severe thunderstorms developing across the region except for Cape Cod and the Islands. Thunderstorms will approach southwest New Hampshire and Western Massachusetts by 1 to 2 p.m., then will push eastward through the rest of the afternoon reaching the Boston to Providence corridor by 4 to 5 p.m.

"The main threats from any possible severe thunderstorms will be damaging winds and large hail," the statement continued. "Trained weather spotters are requested to watch out for conditions that reach reportable criteria and contact the National Weather Service."

NWS said a tornado watch means conditions “are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen to later statements for possible warnings,” said NWS.

Check back with Marlborough Patch as we will be updating this story throughout the afternoon.

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