I have not seen a CAI or SRI for a santa fe...I imagine it would be louder is all it would do given how hot the engine compartment gets. And I don't see much room for routing the CAI to get most of the cold air without modifying at least the bumper...
But just as a thought:
I noticed yesterday that the stock intake may be designed poorly...or at least it could be better. I plugged in my OBD II and drove around with ambient temperature of 73.4F. The intake air temperature was near 96F +/- 4-5 degrees depending on how fast I was moving. This may be comparing apples to oranges, but when I had my 09 WRX and did the same thing, the intake air temperature would near the ambient temperature (slightly higher, but not 23F difference). I know the 09 WRX's intake design is pretty good to begin with...so that's why I feel like my point is moot. hah
Anyways, the Santa Fe's intake at the grill seems to point downwards, which then the air is re-routed by a piece of plastic next to the end of the intake....this to me is very inefficient in getting most of the air from outside of the car....it actually seems like it would draw hot air from under the vehicle as the intake is pointed downwards...
I dunno...pictures probably would have helped. hah
The only way to be sure is to run some controlled tests. Record the temp driving in a straight line at 100kmph and record the ambient temp to be sure. Under those circumstances I'm sure you'll get better results than what you recorded earlier.
The intake follows the flow of air at speed so yes, if the car is standing still and there is no head wind then you'll get a warm reading because the hot air under the hood is escaping from underneath and around the front of the car. In this case the intake will be sucking in warm air but on the highway it will be taking in MUCH cooler air. It's angled down to allow for easier intake and a bit of a ram effect. It's also mounted high to prevent FOD (foreign object damage).