Geoecologist warns of black ice as temperatures swing

Fluctuating temperatures could bring black ice and slippery roads across Estonia in the coming weeks, geoecologist Hannes Tõnisson told ERR’s Terevisioon programme.

Tõnisson said Tallinn was not expected to get snow on Friday, and any snow on roads would melt because the ground was still warm. Snow was already visible in fields in central Estonia and near Tallinn. Observation data showed heavier snowfall in eastern Estonia and around Lake Peipsi, where at least five centimetres could accumulate as a cloud mass moved over the lake.

Rain is expected in most parts of the country on Friday, but colder evening air could bring locally heavy coastal snowfall overnight as winds turn northwesterly and northerly. Snow could also reach the area around Tallinn, although most of the cloud is forecast to pass east of the capital. Tõnisson said heavy snow in Tallinn could not be ruled out, but temperatures are expected to rise on Saturday, bringing rain instead.

Roads could become slippery again on Sunday morning before temperatures rise. The following week is expected to bring mostly above-zero temperatures, particularly near the coast, on the islands and in Tallinn, though clear spells could leave a layer of ice on roads.

Temperatures are expected to remain below zero inland during the week after that. Around St Catherine’s Day, colder weather and heavier snowfall could reach Estonia, with frost possibly reaching 10 degrees below zero or briefly lower in some places, Tõnisson said.

He said long-range forecasts are uncertain because Estonia lies between warm and cold air masses, making conditions changeable. Weather systems arriving from the Atlantic and moving over Latvia can also affect the forecast: small shifts in their position can determine whether Estonia gets rain or snow.