We do pretty good using 9X12 tarps installed over both bed ends of our OFF-ROAD POPUP. This is my poor man GIZMO I guess...
Here is a photo of my setup...

Since there are just the two of us I have also sit a small 5K BTU portable window house a.c unit in the unused bed area. Just sit it on a board with the back sticking out a window flap and used duct tape to seal it off. The only downside is to make sure the runoff goes outside the trailer... That helped a bunch the one or two times we did it.
Best bet is to always try to park under some tree cover. Being from the Wichita Falls areas I know that may be hard to find everywhere.
Another solution is to park under a 20x30 tarp over the top of your hole trailer. Mine has a cutout in the tarp for the roof mounted a/c and the power roof fan...
We have done this camping in the Smoky Mtn Natl Park near Gatlinburg where all of the forest parks are like rain forests - always dripping water days after rain storms...
Just make some shade somehow...
something like this maybe...

Just my thoughts
Roy Ken