The Road Traffic Centre Monday reported the first collisions of the day in Tampere and Hämeenkyrö, both minor accidents, but an indication of how treacherous early morning roads are likely to be in weeks ahead.
Temperatures generally reach overnight lows just before sunrise and can freeze moisture that collects on road surfaces. These spots remain slippery until the sun is high enough to warm and thaw the film of frost. However, according to Yle Meteorologist Elina Lopperi, this phenomenon is uncommon during periods of cloudy weather.
Monday night is forecast to be cloudy in southern and central regions. Tuesday night's forecast includes cloudy skies in the north, but western areas may be clearer and subject to early morning frosts.
Snow tyres are mandatory from the start of December through the end of February but can be used both before and after the required period. Studded snow tyres, however, can be used no earlier than from the beginning of November.