Water Intrusion

[JAFO]

After a heavy rain last week I found the front passenger floor board of my TrailBlazer soaked with water. Found the appearet source, seemed to be water dripping from the shroud around the heater outlets.

 

Has anyone else experinced this? Have any idea where to look to find it getting into the duct work? have any other idea about where the water may be getting in?

 

Any help would be much appreciated!