About 180 people have been killed or are missing after torrential rains and flooding in Yemen, according to the UN agency for refugees.
More than 20,000 people have been left homeless, the UN World Food Programme said, particularly in the eastern area around Hadramut where mud houses were washed away by 30 hours of heavy rain.
On Tuesday, Saudi Arabia pledged $100m in aid to help its poor southern neighbour rebuild.
Ali Abdullah Saleh, the Yemeni president, said Saudi Arabia had also sent food and medicine to the affected areas and that the money would help the authorities to cope with "the aftermath of these catastrophic floods".
Yemen itself has allocated $100m in aid for the victims of the tropical storm and an international aid appeal has been launched.
Attempts to get medical supplies and relief aid to the region have been hampered as some villages are still cut off.
Wells, roads and farms have also been destroyed and power lines remain cut.
Among the affected areas is the Unesco world heritage site of Shibam, where historic mud-brick buildings are threatened with collapse.
Shibam, which was isolated by the flood waters, is home to more than 20,000 people and is famous for its ancient highrise buildings that have given the town the nickname "the Manhattan of the desert".
A cargo vessel also ran aground off the port of Nashtun in Mahra, but all 17 crew members were rescued.
Yemen is one of the poorest countries in the world and its government is already struggling to contain an uprising in the north, unrest in the south and the re-emergence of al-Qaeda in the region.