All good advice except:
check the triple point of water at ground temperature
The triple point is one specific temperature (very close to 0C). It has no relevance to this problem. Perhaps you meant "dew point"?
Most pressure sensors I have used with Arduinos are good for 100% humidity but it is good to check. The real problem with that humidity is if you get a droplet of water blocking the air tube. Mount the sensor so water drains out of it and don't put any U bends in the tube.