NAIROBI , Kenya ( CNN ) -- Heavy rains triggered by El Nino weather patterns could potentially prove devastating for east African nations that have been water-starved for months , the United Nations has warned . A Turkana boy holds an empty cup in a village in northwestern Kenya . Kenya , Somalia , Tanzania and Uganda are facing mudslides , crop destruction , waterborne diseases and disrupted road networks , the U.N. Office for the Coordination of Humanitarian Affairs said Friday . Djibouti , Eritrea and Ethiopia could also be affected . The effects of flooding are expected to be exacerbated because so much greenery has disappeared in the drought . `` More than 23 million people in pastoral , agricultural and suburban communities , as well as internally displaced people and refugees in the region , are reeling from the impact of water and food shortages , pasture scarcity , conflict and insecurity , '' said John Holmes , the under-secretary general for humanitarian affairs who is coordinating emergency relief operations . `` While we can not prevent these climatic shocks , we certainly can mitigate their disastrous effects through forward planning and the right funding from the donor community , '' he said . Uganda , hit by El Nino a decade ago , is planning to apply some of the lessons learned this time around , said Fred Opolot , a government spokesman . `` The government has allocated funds and resources to areas that will be affected , '' he said . `` Our disaster preparedness department is using press briefings , among other ways , to inform the public . '' Though the department is not very well-funded , he said , the government is working with groups such as the United Nations and international aid agencies to prepare for floods . `` It is a multifaceted effort ... we want to ensure citizens are sensitized to the dangers of El Nino and things such as bridges are in good condition . '' The rainy season begins in the Horn of Africa in mid-October and runs through the end of the year . Meteorologists have forecasted that this year 's rains will be more intense than usual because of the El Nino phenomenon , caused by a rise in temperature in the Pacific and Indian oceans . Aid agencies are already buckling under the weight of helping millions of people who have suffered through months of failed crops , drought and erratic rains caused by climate change . In Somalia , 450,000 people in the Juba and Shabelle river basins could suffer , the United Nations estimates . In neighboring Kenya , some 750,000 people -- 150,000 of whom are refugees -- could be affected . The Turkana , a pastoral tribe in northeastern Kenya , is already reeling from a severe drought that has left scores of people dead and remains of skeletal cows strewn across the flat , arid land . The remote region has no access to resources , making it especially vulnerable to natural disasters such as floods . CNN 's Moni Basu and Faith Karimi contributed to this report .
U.N. humanitarian agency : east African nations facing flooding , mudslides . Warning comes after months of drought in region which has decimated greenery . Rainy season in the Horn of Africa usually begins in end of year , runs to end of year . Eritrea , Somalia , Tanzania , Eritrea , Djibouti , Eritrea , Ethiopia set to be affected .