Flash floods hit several cities and towns south of Boston Thursday morning as historic rain brought traffic to a crawl and clogged streets and highways during rush hour.With rain coming down so fast,

A "considerable" flash flood warning has been issued in Boston as heavy, life-threatening rain pounds the city and areas to the south. Two to 4 inches of rain has fallen so far. Rainfall rates are reaching up to 2 inches per hour.

Several Massachusetts communities south of Boston received as much as over 5 inches of rain, with flooding closing several streets and parts of Interstate 93.