Here are the details on potential dangerous heat Monday and possibly Tuesday.

What: Excessive Heat Watch for heat indices of 105 to 109

Where: Eastern MA as well as the Connecticut River Valley.  This includes the Hartford and Springfield area as well as the Greater Boston area

When: Monday and possibly into Tuesday

The heat will be exacerbated by the duration of this event with record highs possible Today, Monday and Tuesday.  In addition, record breaking warmth is possible Monday night when minimum temperatures may only fall to 75 to 80 degrees in the urban centers including Boston and Hartford. 

Attached are two graphics, one with heat headlines and heat indices for Monday. 

Meteorologists Frank Nocera & Glenn Field