What: Shares of Frontline Ltd. (FRO 3.17%) jumped as much as 10% on Tuesday after the oil tanker company reported first-quarter earnings.

So what: Revenue was down 6.7% sequentially to $227.1 million, but net income jumped 25.8% to $78.9 million on lower contingent rental expenses. A broad increase in tanker demand since the middle of 2013 has helped the bottom line and with U.S. oil imports up and global demand growing that trend should continue. 

What'll be important to watch this year are dayrates for tankers. Management expects prices for all rig sizes to fall in the second quarter and that could hurt earnings power going forward.  

Now what: Frontline is experiencing a lot of tailwinds with demand for offshore inventory storage as well as a growing number of tankers being used shipping oil around the world. That should help drive the company's earnings going forward and could keep a lofty dividend yield of 7.5% intact. Investors should continue to expect volatility given the oil market changes happening around the world, but right now conditions are looking up for Frontline.