An undersea earthquake with preliminary magnitude 4.6 occurred Friday in the sea area between Crete and Kasos, the Athens Geodynamic Institute said.
There were no immediate reports of injuries or damage.
The Athens Geodynamic Institute said the quake struck at 8.57 a.m. some 49 kilometers northwest of Kasos, at a depth of 27.5 kilometers.
According to the announcements of the Republic Hydro-meteorological Institute (RHMZ), temperatures below zero will remain for at least another two to three days.
"For the weekend and the beginning of next week, very cold weather with moderate and strong morning frosts and daily temperature below 0 degrees. From Tuesday, the temperature will rise," it is stated on the RHMZ website.
Atmospheric pressure is rising and during the day will already be higher than the average for the month.
It will be sunny with more clouds over the northeastern regions. Light west-northwestern wind will rise to moderate in northern Bulgaria. Maximum temperatures will be between minus 3°C and 2°C, according to the national weather service forecast.