'03 Outback cabin humidity issue



I bought this car in 2008, it now has just under 100,000 mi. It runs fine but fogs up on the inside of the windshield quite often, especially in colder weather (meaning there’s a lot of humidity in the cabin). Other than running the defogger (which keeps the AC on) and short of hooking up a household dehumidifier to my inverter, is there anything that can be done to improve air flow in the car when the windows are up? A drain plug or exterior vent that might be clogged? I always have the fan blowing in at least the “1” position. Singing to the radio often fogs the glass even if it’s not very cold out. And after being parked in the sun for a day, there was recently a TON of condensation above the dashboard. Any ideas will be appreciated!



Watch the level in the coolant reservoir for any slow loss. That could be a leaky heater core.
Check under rugs etc. for any water collecting from a leak.


Leaving the vent in the recirculating postion constantly may cause this.