Burgas can expect rain on some days and rough seas with waves up to about 3 metres, climatologist professor Georgi Rachev said in a TV interview.

He links the coastal rain to swirls of low pressure over the Black Sea. Small cyclones bringing cloud and rain are likely over southeastern Bulgaria and along the coast. The sea will have a strong effect on the weather in Burgas, and wind will play a big part too.

October will start with typical autumn weather: high pressure, cool mornings with fog, and temperatures around normal or a touch above. A powerful area of high pressure is settling over European Russia, Rachev said. Its centre will shift, but Bulgaria will stay on the edge of it. The eastern side of this high will bring cooler air.

Morning fog is also expected in the west, where rain will be light. Next week Sofia will see highs of around 21 degrees and noticeably cool mornings. Under clear skies, the high valley basins could wake up to the first frost. Because of the sea, mornings in Varna will be warmer than inland.

Rachev put the odds of next week's forecast holding at 80%, with rain possible in the other 20% of cases. For the weekend after that he was more cautious, putting the odds at 50-50 and saying a forecast that far out is more like guessing.

No heavy rain is in sight for now, but water levels in the dams are in good shape, Rachev said. The Danube is still catching up, since rainfall across much of Europe hasn't been enough.

September is ending about a degree and a half above normal and dry, he added.