Broken/Wrong "Outside Temperature" reading.
 

So I took this yesterday: http://i.imgur.com/ZajjABb.jpg

(Note: That's an accurate reading... ugh)
And today it's sitting at 75F, which is clearly wrong. Is there some sort of reset that I can do on this? Or did the crazy heat nuke the sensor from orbit?

The ambient sensor is located in front of the radiator on the center support bar.

Check to see if its loose or did you happen to have an oil cooler installed?

As the heat off the oil cooler will throw off the temp sensor and so it needs to be relocated further away of the oil cooler if thats the case.

If not? Your sensor maybe bad.

Would it have been possible to break/pop loose while washing my car with a power sprayer? I did that today too...

Hrrrm.

Edit: Not loose, but entirely in a position where it most likely got water sprayed on/in/around it. I'll give it a bit to see if it just needs the water to evaporate or something.

My gauge is NEVER right when I first crank, it's always higher than ambient, guess it's the car roasting in the sun that does it, although I always try to park in shade. Shade has its drawbacks too....

You may have sprayed some water into the connector. Unplug the connector from the sensor and dry it out.