A fierce winter storm shut down much of the Middle East Friday, burying Jerusalem in snow, flooding parts of Gaza and bringing frigid, wet weather to war-ravaged Syria.

The hilltop city of Jerusalem was paralysed by its fiercest snowstorm in years, with its mayor calling out the army to help stranded motorists and authorities urging residents to stay indoors.

"We are battling a storm of rare ferocity," Mayor Nir Barkat said as snow in the Holy City piled up to around 37 centimetres (15 inches) and thousands of homes lost power.

Main roads into the city, which climb around 795 metres (2,600 feet) above sea level, were closed and police appealed to drivers not to attempt the journey.

Already by mid-morning police had been called to help about 1,500 drivers in the city and on the roads leading to it, police spokesman Micky Rosenfeld told AFP.

He said about 1,000 stranded travellers were given shelter at the Jerusalem International Conference Centre while hundreds more were taken to a nearby military base.

Young and old, ultra-Orthodox Jews and secular Israelis camped on mattresses in the conference centre, many of them glued to mobile devices.

In a rare move, authorities allowed trains to depart from the city after the start of the weekly Jewish sabbath at sundown.

Snow was still falling into the night Friday, as Barkat told Channel 1 television that 25,000 households in Jerusalem were without power.

Ramallah and Bethlehem, Palestinian cities near Jerusalem, were also coated in snow and some lower-lying areas suffered flooding from heavy rain.

The Gaza Strip was lashed by torrential rain for a third day, and its Hamas rulers said residents had been evacuated from 60 flooded homes since storms hit the coastal territory on Wednesday.

The severe weather prompted Israel to open the Kerem Shalom crossing into Gaza to allow in humanitarian aid following a UN request.

In Syria, meanwhile, a child and a baby were said to have died from the cold Thursday, and an activist in a besieged rebel-held town said residents were struggling to stay warm with electricity cut off and no food or fuel allowed in.

"Normally we face the shelling and fighting, as well as food and fuel shortages. Today we also have snow and extreme cold," Abu Anas said by Internet from the town of Hara.

"The worst part is that children and the elderly cannot resist the cold as much as the young people can... We feel completely cut off from the world."

Syria airlift delayed again

The UN refugee agency (UNHCR) had to delay its first planned international aid airlift into Syria a second day but said weather conditions there were improving.

The agency hopes to fly in some 40 metric tonnes of aid from northern Iraq.

Farther east, blizzards left thousands of drivers stranded in Iran.

"Rescuers have helped some 6,600 people and more than 1,700 vehicles that got stuck in the heavy snow" since Thursday morning, Mahmoud Mozafar, head of the local Red Crescent Society, told the ISNA news agency.

As residents elsewhere in the region hunkered down and motorists navigated blinding flurries and icy roads, Egyptians took to social media to share rare photos of snow in their normally balmy country.

"The whole garden was white," Karim Kheirat told AFP by telephone from the new town of Medinati northeast of the capital.

"It's the first time in my life that I have seen it like this."

Other suburbs of the capital also saw light snow showers, residents said.

In the Sinai Peninsula, the storm deposited a blanket of snow several centimetres (inches) thick in the mountainous area around Saint Catherine's monastery for the first time in decades.

Mokhtar Hussein, who lives in the area, said he had not left his house since Thursday because "the whole town is covered in snow."

The northern coastal city of Alexandria only received light snowfall, but authorities shut the port for the third consecutive day because of the bad weather and strong winds.

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