The rain comes amid one of the largest influxes of refugees into Jordan since the Syrian conflict began nearly two years ago. In the last eight days, 10,183 Syrians fled to Jordan, according to Anmar Alhmoud, rapporteur of the Prime Ministry's higher steering committee for Syrian affairs in Jordan.
"Our feet are sinking in mud," said 37-year-old Mohammad Amer, a resident of Za'atari refugee camp in the northern town of Mafraq. "You can see people trying to rebuild their tents after floods and wind. It was terrifying for people last night. Strong wind was blowing and tents were destroyed. Some 80 families were outside their tents late at night."
"Tents are drowning," another refugee told IRIN. "People are staying in kitchens, bathrooms, schools, aid workers' offices, anything that will protect them from the rain."
Za'atari camp's population has been rising quickly in recent weeks, with an average daily arrival of 1,100 people. It is now home to 54,000 Syrian refugees, according to official UN Refugee Agency (UNHCR) registration figures, and 63,000 according to Mahmoud Omoush, who manages the camp on behalf of the Jordan Hashemite Charity Organization (JHCO). More than 900 people crossed the border last night, he said.
Sixty families living in tents in lower areas of the camp were moved to so-called pre-fabs - pre-fabricated homes akin to caravans - after water seeped into their tents, Alhmoud said. Two weeks ago, Saudi Arabia donated 2,500 pre-fabs, which are more resistant to wind, snow and rain, but they were not yet inhabited, awaiting sewage treatment and communal kitchens to be set up.
"We are facing a huge challenge," said Ali Bibi, a liaison officer with UNHCR in Jordan. "We are in the process [of moving people]. But we can't move them all at once." UNHCR says there are not enough pre-fabs for everyone.
The harsh weather did not kill or injure anyone, but things could get worse, with a "North Pole kind of storm" on the way.
"The forecast for tomorrow says more rain and more snow; we hope we survive both," Alhmoud told IRIN. "It's not life-threatening. But it is serious. We have to have more tents."
Omoush said refugees started building dams this morning to prevent floods.
"An emergency plan has been put in place," he told IRIN. An online video showed large puddles of water at the entrance to many tents, while refugees were using shovels to dig channels.
Za'atari camp, opened in July to accommodate a growing number of Syrian refugees and asylum seekers (Jordan hosts nearly 175,000, according to UNHCR), has seen refugees often protesting about harsh desert conditions in summer and winter.
The rare rain, Alhmoud said, is further "complicating things" in an already tense environment.
"It is a frustrating feeling to not be able to protect yourself from the rain," Bibi said.
Today, a group of young men attacked aid offices with stones and chairs in what refugees described as an expression of their frustration, aid workers described as a riot, and Alhmoud described as opportunistic violence.
"The situation is awful," said Dalia*, a mother-of-three in the camp. "People started running to caravans meant for aid workers and their offices. They want to feel warm too," she told IRIN.
"They promised us caravans for winter," said another Syrian woman who fled her tent with her wounded husband and children. "Winter is here. It is freezing and the rain is so heavy, but nothing has been done. People are so angry with the service and this is why they started attacking offices."
Rioters entered the distribution compound of the World Food Programme (WFP) during bread distributions, injuring five staff and two volunteers of WFP's partner, NGO Save the Children. Four WFP staff were also caught up in the fighting, the UN agency said. Omoush said one of the aid workers was hit in the head and transferred to hospital.
The camp is home to about 2,000 single young men, Alhmoud said, who "exploit any moment for anything for no reason at all to agitate and throw stones and even jeopardize the aid they are receiving. It is quite irresponsible. They have done it [before] and gotten away with it."
"While we understand the anger and the frustration, we will continue to work with all partners on the ground and the Jordanian authorities to improve living conditions for refugees in the camp," WFP told IRIN in an email.
Alhmoud said camp authorities will move all single males to Cyber City camp in nearby Remtha town by the end of the month to remove the "potential threat" to the "rest of the more vulnerable" in the camp.
In need of funding
They also have back-up plans in case the weather gets worse.
The Bahraini school complex in the camp can accommodate some 4,500 people if necessary. The large UN membrane tents used for storage, distributions and registration of refugees could also be used to shelter people.
For now, Alhmoud said, space was not a problem, despite the increasing new arrivals and destruction of tents. The Jordanian government will open another camp (capacity 6,000) by 25 January, 35km east of the northern industrial town of Zarqa, he said.
Still, government officials and aid workers pleaded for more international assistance for the Jordanian effort, to supply badly-needed pre-fabs, heaters and infrastructure to help deal with winter.
"We are asking you to help us so that we can help the refugees and maintain the open border policy," Alhmoud said.
The UNHCR's Bibi described donors' current contribution to the crisis in Jordan as insufficient.
"The international community has to play their humanitarian role in providing the funds to have more caravans in the camp, so that we can be able to move the families from the tents to the caravans. But we are in need of financial support," he told IRIN.
The UN appealed in December for more than US$1 billion to help Syrian refugees in the region in the first half of 2013, including $495 million for the response in Jordan. Past appeals were consistently under-funded.
*not a real name