I've had my GS350 for about four months. Up until recently I felt the auto settings worked pretty well but for the last few weeks it seems like it's not as warm. When I leave for work in the mornings I usually set the temp at 78-80 and in the past it always felt fine but now I've noticed that the air coming out of the front vents is a little cool and in order to not feel too cool I bump it up a couple more degrees.

Anyone have this happen or any explanation?

 

I have only ever had mine up to 76 in the summer in short sleeves.
Wearing even a light jacket, I'm usually below 72.

I would say you definitely have an issue, one that may well have been getting steadily worse.

 

When the A/C is on, the air feels cooler because the humidity has been removed, even if it is the same temperature. Perhaps that is your issue.

 

AC is not on. I changed the climate control settings so that the only way for AC to come on is if I manually do it or if I toggle the vent/recirc button to Auto.

What I'm experiencing for example is that when the temps were much colder in the mornings, say 40-50 I was warmer with the Auto climate control set to 78 than I am when outside temps are 60 and still set at 78.

 

I have a similar problem, I think my cabin temperature sensor is reading too high, and putting out colder than required air. Selecting 33C puts out lukewarm air, one step up to HOT makes it blow really hot air.