http://www.bostonherald.com/news/regional/view.bg?articleid=1061148665&srvc=rss
‘Explosive’ weather warning for Bay State
By Renee Nadeau Algarin
Thursday, July 26, 2012 - Updated 1 hour ago
Meteorologists are warning of the potential for “explosive weather” later this afternoon in Massachusetts, including the possibility of flash flooding and even tornadoes in the Berkshires.
And the warning sign to watch for? The sun.
“We have a lot of clouds across the area. The sunshine will provide the trigger to destabilize that very moist air mass, and that will result in severe weather. If the cloud cover doesn’t clear out, then the prospects of our anticipation of severe whether would be far less,” Charlie Foley, a meteorologist with the National Weather Service in Taunton said.
The storms are being brought in by a warm front moving from south to north and made up partly of a tropical mass bringing lots of moisture, Foley said. How hard they will hit depends on the sun.
“We expect the sunshine to arrive and destabilize the air mass, and that could result in, again, explosive weather,” said Foley.
Updated information from the National Weather Service shows cloud cover breaking up as the warm front moves toward the Bay State. The warm front was moving over Pennsylvania around 2 p.m. and is expected in Southern New England by 4 p.m. or 5 p.m.
The National Weather Service has issued a hazardous weather outlook for parts of the Bay State warning of dangerous “supercell” thunderstorms and said that the possibility of tornadoes could not be ruled out..
Foley said the greatest potential for funnel clouds is in Connecticut, but parts of Massachusetts — even the metro Boston area — could see a twister.
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The National Weather Service also issued a flash-flood watch for much of the state lasting from 4 p.m. today through tomorrow morning. Dangerous torrential downpours are expected to inundate areas with upwards of two inches of rain in a short period of time, the agency warned. Significant flooding may occur in urban and poor drainage areas, meteorologists warned, also citing the danger of flooding from small streams.
Other threats from the incoming storms include damaging winds of 60 miles per hour or more and hail, according to the National Weather Service. The chance of thunderstorms persists through early Sunday, as meteorologists expect a separate line of storms to move in from the west.