Sunny conditions are expected across much of Bulgaria on March 13, according to the latest forecast from the National Institute of Meteorology and Hydrology (NIMH). During the morning hours, some parts of the lowlands may see fog or persistent low clouds. As the day progresses, these will gradually clear in most regions, allowing sunshine to dominate the afternoon. Winds across the country will remain generally light to moderate, blowing from the east-northeast.

Early morning temperatures will be relatively low, ranging from about minus 3°C to 2°C across the country. In Sofia, the temperature at the start of the day is expected to be close to minus 1°C. Daytime values will rise significantly under the sunny skies, reaching between 13°C and 18°C in most areas. The capital is forecast to see a high of around 14°C.

Conditions in the mountains will also be mostly sunny, although some temporary increases in cloud cover may appear later in the day. Winds at higher elevations will be light to moderate from the east-southeast. Maximum temperatures will remain cooler compared with the lowlands, reaching roughly 9°C at around 1,200 meters altitude and close to 2°C at 2,000 meters.

Along the Black Sea coast, calm conditions are expected before noon, with patches of fog or low stratified clouds in some coastal areas. These are forecast to gradually disperse in the afternoon as the clouds begin to break. A light to moderate east-northeasterly wind will develop later in the day. Daytime temperatures along the coast will stay lower than inland, generally between 8°C and 12°C. Sea water temperatures are estimated at 6°C to 9°C, while wave activity will remain relatively mild at around two points.