Summer rainfall records and the threat of flash floods: forecast and warnings
More than 20 mm of rain, for the fourth time since records began: following heavy downpours in the Jerusalem area, flash floods are possible tomorrow in the Judean Desert and the Dead Sea. Experts link the anomaly to the "super El Niño" phenomenon.
After a day in which the August rainfall record was broken, there is again a chance of floods in mid-summer. The Meteorological Service has issued a "yellow early warning" for flash floods in the Judean Desert, the Dead Sea area, the northeastern Negev, and the northern Arava between 12:00 and 21:00 tomorrow (Sunday).
Following the flood risk, police announced they would be deployed in areas where roads might be blocked. The public is urged to plan trips in advance, adapt travel routes to weather conditions, and avoid high-risk areas, including stream channels. The Nature and Parks Authority emphasized that it is strictly forbidden to enter stream channels with flowing water on foot or by vehicle until the water level drops completely, and warned against approaching the edge of a stream during a flood due to the risk of bank collapse.
Temperatures tomorrow will remain similar. On Monday, a slight cooling is expected, heat loads will ease, and morning drizzle is possible along the coast. In the mountains and inland, temperatures will be below average. Tuesday will be partly cloudy with no significant change in temperature.
Today, very heavy rain fell in the Jerusalem area and the northern Judean Desert. At the Ma'ale Adumim station, an all-time record was broken: 21 mm of rain in one hour, with a total of 25 mm. The heavy rains caused flooding in neighborhoods in the south and east of Jerusalem. In the Og stream, the beginning of a flood was documented—the first ever recorded in this area at this time of year. In central Jerusalem, 4 mm fell, while 13 mm was measured in Kibbutz Rosh Tzurim in Gush Etzion.
The director of the Meteorological Service, Dr. Amir Givati, stated:
"This is a historical record of rainfall amounts, flooding, and flash floods for this time of year. The highest amount of rain measured so far in the Jerusalem area in August was one millimeter, about a hundred years ago on the Mount of Olives."
Nationwide, a rainfall event of more than 20 mm in August is extremely rare, having occurred only three times since records began: in the Golan Heights (2012), Acre (1990), and Kfar Galim (1971). According to Dr. Givati, this rare event can be linked to the "super El Niño" phenomenon, which is intensifying globally and is expected to affect Israel in the coming months. The Meteorological Service warns that the upcoming autumn is also expected to be rainier than usual, with a possibility of unprecedented flooding.
