In March, the weather in Sveti Vlas is typically warm. Average daily high temperature in March is about 10 degrees above zero. On average, Sveti Vlas has 10 partly cloudy, 9 sunny, 8 rainy, and 4 cloudy days in March. The rains are usually moderate. March as well as January, February, and December is considered the most uncomfortable time to visit Sveti Vlas.