site.btaThe Weather on December 19

Foggy before noon. Sunny in the afternoon. Highs: between 9C and 14C, between 4C and 8C in foggy areas, around 8C in Sofia. 

The coast 

Foggy before noon, sunny in the afternoon. Light to moderate wind, south-southeasterly. Highs: between 11C and 13C. Sea water temperature: between 10C and 12C. Sea swell - 2 Degrees Douglas.
 
The mountains

Mostly sunny. Light to moderate wind, west-northwesterly. Highs: 9C at 1,200 m, 3 C at 2,000 m.

Source: National Institute of Meteorology and Hydrology