Heavy rain from the approaching storm system known as “Byron” began falling Monday evening, with forecasters warning that the most severe conditions will hit Israel late Wednesday and Thursday morning. Total rainfall is expected to reach about 200 millimeters, with dozens of millimeters — potentially up to 100 — falling within a few hours.
Arik Leibovitz, director of the Yarkon Drainage and Rivers Authority, told ynet that no city can withstand 100 millimeters of rain in 24 hours. “If this happens in Tel Aviv, it will be a catastrophic event,” he said. “We cannot fully protect the city. It is a dense urban area with national infrastructure.”
Heavy rainfall in Tel Aviv
Rain was already reported in Tel Aviv on Monday night. Recent storms have brought flooding from Eilat to the Ayalon basin, raising concerns as the stronger system approaches.
Leibovitz said even well-prepared cities can usually handle only about 30 millimeters in a day. “Beyond that, flooding is inevitable,” he said. “The question is how much falls in one hour. No system can absorb such volumes in such a short time.” He estimated that proper flood preparedness would require about 4 billion shekels and said current funding levels are insufficient to protect infrastructure such as the planned metro.
He warned that heavy rainfall events have intensified in recent years. “We used to get 100 millimeters in a month. Now the same amount falls faster and with stronger intensity,” he said, adding that cities struggle to cope. He called for the government to declare climate change a national crisis and to establish a budgeted cabinet including agencies responsible for infrastructure.
The storm’s main impact is expected as Byron arrives Wednesday, bringing widespread rain to the north and center, flooding risks along the coast and in the lowlands, and flash floods in the Judean Desert. The Israel Meteorological Service said peak conditions will include 80 to 100 kilometer-per-hour winds, heavy downpours within hours, urban flooding and disruptions to transportation. Up to 200 millimeters of rain are expected in parts of the northern and southern coast and the Tel Aviv area, amounts well above the December average. Rain is forecast to continue into Friday.
“Most people will feel the impact Thursday morning,” said Dr. Amir Givati, head of the Meteorological Service. He said the main concern is the volume of rain expected in a short window, particularly along the coastal plain and the Dan region. The heaviest rainfall is expected during peak commuting hours, complicating drainage on major roads.
Drainage authorities have moved into emergency readiness. A recent State Comptroller report noted persistent challenges, including debris and excess soil restricting flow along the Gezer Stream, increasing the risk of flooding near residential areas. Flood and storm damage in Israel totals billions of shekels each year, while global losses from similar events were estimated at about $651 billion between 2000 and 2019.
Environmental groups also urged action. Mor Gilboa, director of the nonprofit Zalul, said climate change is driving more frequent intense rainstorms and that local governments must improve runoff management to prevent pollution from floodwaters. He called for more natural absorption zones in urban plans and better separation of drainage and sewage systems.
Farmland could also suffer significant damage. The government-backed agricultural insurer, Kanat, urged farmers to reinforce greenhouses and plastic coverings to prevent collapse and protect crops from heavy rainfall.