Not sure where you are camping, but if the air is very dry ( as it is here right now) you may not see a lot of water running off the roof. Also the weep holes in the base pan of the unit may be plugged. If that is the case, it will overflow after some water accumulates. Depending on which side of your unit is the low side, it may run off somewhere other than where you expect.
2015 Freedom Express 248RBS
TV 2015 Silverado HD2500 Duramax
TST Tire Monitors
Honda 2000I + Companion
2 65W solar panels