The advice I've always heard is to wear the suit and adapt as the day goes on. If you are confronted with a room full of blinking shorts and sandals types then

The advice I've always heard is to wear the suit and adapt as the day goes on. If you are confronted with a room full of blinking shorts and sandals types then you gratefully pull off the tie, drop the coat, unbutton the collar, and roll up the sleeves while saying something about "glad you guys won't expect me to suit up".