Overview: Sveti VlasSveti Vlas (Bulgaria) in general has a mild climate. The day temperatures range from 6 °C (42 °F) in January to 27 °C (81 °F) in August. The least rainy month in Sveti Vlas is August with its 4 days of rain, the rainiest month is June, when it rains 8 days. The highest sea temperatures in Sveti Vlas are in August with 25 °C (76 °F) and the lowest in February with 6 °C (44 °F). The highest night temperatures could be experienced in July with 18 °C (64 °F), the lowest in February with -1 °C (30 °F).