Remove it with a wet/dry vac.
They can get as hot as 170 degrees! WOW!
heater core is shot...
you left the windows down while it was raining
There are only two possibilities for the water leak in the 1993 Mercury Marquis. The car could have a leak allowing rain water in. Or, the drain for the ac could be stopped, and condensation is leaking into the car. The condensation is your most likely cause.
boards
"Floorboards" are tongue and grooved wooden planks that are used to make wooden floors.
you need to replace your heater core.
Most likely your heater core has gone bad.
underneath the floorboards of the train In their hard wooden seats. Pullman had not yet invented his famous sleeping car.
yes
He tried to sneak quietly through the house, but the creaking floorboards gave him away.
I guess you're asking where is the water coming from. It stands in the floorboards because they don't leak or drain to the pavement. (unless of course, there IS a hole in the floor. That would be a prime suspect) The water (are you sure it's not coolant?) can only be coming from a few places. Windows, Door Seals, Sunroof, Heater Core and maybe the AC drain. You can sit in the car and have someone have at it with a hose. Look for water entering. Or, you might be able to talk you local car wash into letting you ride through while it's being washed. That's a good way to look for leaks. If you localize the leak, it may just be a matter of replacing the weather stripping. Has the car ever been in an accident? If so, you might have a damaged door panel that's letting water leak in.