MADRID (REUTERS) - Schools in Madrid were shut, some supermarkets ran out of fresh produce and few cars except emergency service vehicles were on the city streets on Monday (Jan 11) after a huge snow storm hit the Spanish capital and several regions over the weekend.

Most flights and trains, including the high-speed link to Barcelona, have resumed operations, however.

While many people enjoyed the rare snowfall by skiing in the centre of Madrid and holding mass snowball fights, a further cold spell was set to turn the snow into ice this week and authorities rushed to clear more streets.

They said, though, that it could take one or two weeks to complete, and on Monday snow ploughs only managed to clear a single lane on some avenues because of fallen trees blocking their path.

Residents of Madrid, which saw its heaviest snowfall in at least 50 years, helped police open paths through deep banks of snow using plywood boards or trays, and poured salt on the underlying ice.

With blocks of melting snow occasionally falling from rooftops, police have cordoned off some pavements, and residents took to walking in the middle of the road.

The storm, which dumped up to 50cm of snow on Madrid, has hampered Spain's efforts to increase the pace of its coronavirus vaccination programme amid rising infections.

A new batch of vaccines meant to land in Madrid was diverted on Monday to Vitoria-Gasteiz in the north, but city authorities said vaccinations in care homes and hospitals continued as planned.

Access to two factories in Madrid operated by pharmaceutical company Rovi, which handles the final stages of production for Moderna's recently approved vaccine before its export across Europe, were blocked by snow, Reuters TV footage showed.

Rovi declined to comment.

'Complicated situation'

Two runways at Madrid's Barajas international airport re-opened and the airport was returning to normality, authorities said, although out of around 400 flights scheduled to fly in and out on Monday, 117 had been cancelled.

A Reuters reporter saw a number of empty shelves at several central Madrid supermarkets.

The Spanish supermarket association urged customers to behave responsibly in the wake of a "complicated situation" in many storm-affected areas. But it said supplies had resumed in the early hours on Monday and were gradually increasing.

Mercamadrid, the city's main wholesale food market, said convoys of trucks which had been stranded in the snow since Friday had started arriving and that it was preparing to resume activity from Monday night.

About 85% of the bars and restaurants in Madrid that had been open despite Covid-19 were still closed because of the weather, the Hosteleria de España association said.

Interior Minister Fernando Grande-Marlaska said the situation on the roads was improving but was still "extraordinary" and many remained closed.

The cold wave, with temperatures as low as -10 degrees Celsius in central Spain, will last until Thursday, the Aemet meteorological agency said.