Temperatures on the Black Sea coast will reach 17-19C on Tuesday, 20 October, and the sea will be 17-18C, the National Institute of Meteorology and Hydrology (NIMH) said. Waves will be around force 2.
Visibility will be poor in places along the coast in the morning. Cloud over the sea will vary and will start to clear around midday. A light to moderate wind will blow from the east-southeast.
Cloud will thicken for a time over eastern Bulgaria, with light rain in places before noon.
The night into Tuesday will be clear and cool in most of Bulgaria. Lows will be 5-10C, around 5C in Sofia and down to 1C in the valleys of western Bulgaria. In the east, cloud will be patchy but mostly thick, with light showers in places in the northeast.
The wind will die down overnight, and in many areas there will be none at all. In the morning, visibility will be worse in places in lowlands and near rivers.
Tuesday will be mostly sunny across Bulgaria, with highs of 18-23C and around 19C in Sofia. The wind will be light from the east-southeast, and moderate in the east.
The mountains will be sunny too. Temperatures will be around 13C at 1,200 metres and around 7C at 2,000 metres. The wind there will be up to moderate, from the west-southwest. Air pressure will be slightly above the October average.
On Wednesday, 21 October, it will again be mostly sunny. There will be fog in places on the plains before noon, and broken mid-level and high cloud will pass over western Bulgaria in the afternoon. Lows will be mostly 7-12C and highs 19-24C.
The wind on Wednesday will blow from the south-southwest, up to moderate strength. It will pick up for a time in eastern Bulgaria and north of the mountains.
On Thursday, 22 October, cloud will build from the west, and rain will fall in places in western Bulgaria by evening. The wind will keep blowing from the south-southeast, and the weather will stay fairly warm.