Well, as you are probably aware the normal flow of water from the AIR Conditioner is on the roof to the drains just like rain water.
My guess is that your unit froze up and created ice internally and then the ice melted.
From the interweb:
"If your air conditioner
is low on refrigerant, then your air conditioner
up. This is due to lower pressure inside the system itself. ... As your air conditioner's
evaporator coil drops below freezing
, the moisture in your air
as it comes into contact with your coil causing it to ice up"
But lets see what the experts say.