I notice car thermo will be higher with engine heat contamination. Like that 109 earlier ...lol...I was idling for 5 minutes with no breeze. If you are cruising on I93 it should not be wildly high, maybe a few degrees.
Worked in and out of the heat from 5:30am to 2:30pm. Sensational day, everyone outside enjoying the weather. Another reason the heat is great; can fast for 18/24 hrs., and just drink water without being hungry!