I’m not sure it will be a heat wave with 3 consecutive days in excess of 90 degrees but it will be close. This is one of our computer models that shows a fairly impressive surge of heat over the next 72 hours.
Inland winds will tend to stay out of the west through Thursday which keeps the marine influence at bay and also downslopes into the valley off the Litchfield Hills. 100 degrees is possible on Thursday if the clouds stay away and winds remain gusty out of the west. HFD and BDL bake on westerlies but if the winds back to the south-southwest or south temperatures will wind up several degrees cooler.
Here’s another way to visualize the heat using a NAM 850mb temperature forecast. 20c is pretty darn warm and just about all of our models show 850mb temps above 20c late Wednesday and Thursday.