 Here's the WGAW1340.com exclusive National Weather Service forecast for north-central Massachusetts and southern New Hampshire. Overnight, mostly cloudy, chances showers and thunderstorms low around 70. Thursday, mostly cloudy, chances showers and thunderstorms high near 84. Thursday night, mostly cloudy, chances showers and thunderstorms low around 68. Friday, partly sunny, chances showers and thunderstorms high near 84.