How long have you had this car? If it's been years and you haven't had the a/c worked on and checked, you might need a full tune-up. Your possible issues: 1)You drive too hard - the compressor will shut off and blow warmer when you get close to full throttle. 2)Your engine is overheating - the compressor will kick off when a thermal threshold is reached...but it will turn back on when it cools off. 3)The Compressor is failing - less likely from what you described, but possible, it will get worse and worse as you use it and usually make a grinding/whirring noise soon. My bet is # 2), which can include a bit of # 1), if you are low on engine coolant/oil, engine is running poorly because of tune, of a/c needs recharge WITH system lubricant, I won't be surprised. Can you check any of those things yourself? Cheers!

How long have you had this car? If it's been years and you haven't had the a/c worked on and checked, you might need a full tune-up. Your possible issues:

1. You drive too hard - the compressor will shut off and blow warmer when you get close to full throttle.
2. Your engine is overheating - the compressor will kick off when a thermal threshold is reached...but it will turn back on when it cools off.
3. The compressor is failing - less likely from what you described, but possible, it will get worse and worse as you use it and usually make a grinding/whirring noise soon.

My bet is # 2), which can include a bit of # 1), if you are low on engine coolant/oil, engine is running poorly because of tune, of A/C needs recharge WITH system lubricant, I won't be surprised. Can you check any of those things yourself? Cheers!