The Spanish government will send convoys carrying the COVID-19 vaccine and food supplies to areas cut off by Storm Filomena, which brought the heaviest snowfall in decades across central Spain and killed four people.

In the Madrid area, rescuers reached 1500 people trapped in cars, while police broke up a large snowball fight after authorities appealed for citizens to stay at home for risk of accidents or spreading coronavirus.

Forecasters warned of dangerous conditions in the coming days, with temperatures expected to fall to up to minus 10 degrees next week and the prospect of snow turning to ice and damaged trees falling.

“Due to the heavy snow in Madrid the airport has suspended operations at least until Sunday evening – if you are flying to or from Madrid, follow @aena or contact your airline,” Foreign Minister Arancha Gonzalez Laya tweeted.

Wow!, Spontaneous snow battle in the most important street of Spain, biggest snowfall of the century! 😍❄️❄️❄️ pic.twitter.com/B71IRpaCUB

— TRIF 💃 | SSP 💛 | 69% 🖤 (@TrifSmash) January 9, 2021

About 20,000 kilometres of roads across central Spain were affected by the storm and the government would on Sunday send convoys transporting the vaccine and food supplies to those in need, transport minister Jose Luis Abalos said on Saturday.

A 36-year-old woman gave birth in an ambulance in Madrid on Saturday after health workers were unable to get her to hospital.

People walk along a street with fallen tree branches after heavy snowfall in downtown Madrid on Sunday. Photo: AP

One man and a woman in a car drowned after a river burst near Malaga in the south, while two homeless people froze to death in Madrid and Calatayud in the east, officials said.

State metereological agency Aemet said up to 20 to 30 centimetres of snow fell in Madrid on Saturday, the most since 1971.

Storm Filomena brings heavy snowfall to parts of Spainhttps://t.co/VRvyd7Zu3h pic.twitter.com/jxt5iu47ct

— BBC News (World) (@BBCWorld) January 9, 2021