Hmm .. that journey is surely more than just a weekend trip ?
There are direct flights and trains for this journey. Hyderabad (Andhra Pradesh) to Thiruvananthapuram (Kerala) distance is 1301 km and you can get there by flight in just over 2 hours and 50 minutes or by train fares starting from ₹ 521.
The weather is amazing right now. You'll have a great time.