Even before the sharp change in weather expected Saturday night, which is forecast to bring a significant and unusually heavy rain event focused along Israel’s Mediterranean coast, temperatures Thursday are expected to remain largely unchanged and above average for the season.
Heavy to extreme heat stress is expected across many parts of the country, particularly in the mountains and inland areas, the Dead Sea region and the Arava desert. Heavy heat stress is also forecast along the coastal plain. The Mediterranean will be choppy, with waves of 16 to 28 inches (40 to 70 centimeters).
Flooding in Jerusalem amid unusual August rains
(Video: Fire and Rescue Services )
Temperatures are expected to fall slightly Friday, mainly in the mountains and inland areas, returning to seasonal averages. Heat stress is also expected to ease.
No significant change in temperatures is forecast Saturday, though drizzle or light local rain could develop as early as the morning, mainly in northern Israel. During the night between Saturday and Sunday, local rain is expected primarily in northern and central Israel, with isolated thunderstorms possible in the north. There is also a risk of localized flooding along the coastal plain.
Local rain is expected to continue from northern Israel to the northern Negev from Sunday morning through midday. Winds will strengthen and temperatures will drop considerably, falling below seasonal averages, particularly in the mountains and inland areas. Heat stress is expected to ease significantly.
Forecasters expect the rain event to peak before dawn Sunday, when coastal areas could receive about 0.8 to 1.2 inches (20 to 30 millimeters) of rain within just one to three hours.
The rain could be accompanied by thunderstorms, lightning and even hail. Because large amounts could fall in a short period, forecasters warn of a significant risk of urban flooding and disruptions, including in the Tel Aviv metropolitan area and the Shfela region in central Israel.
‘Nothing like this has ever happened in August’
What makes the approaching system unusual is not only the amount of rain forecast but also that it follows another significant rain event earlier this month.
Israel has never recorded an August with two rain events producing more than 0.4 inches (10 millimeters) of precipitation, according to the Israel Meteorological Service. If the current forecast materializes, the agency says it would mark an unprecedented event in the country’s recorded weather history.
“Nothing like this has ever happened in August,” Israel Meteorological Service Director Dr. Amir Givati said.
Flooding in Jerusalem amid unusual August rains
(Photo: Alex Kolomoisky)
Heavy rain fell in northern Israel, the Jerusalem area and nearby communities in mid-August. At the Israel Meteorological Service station in Ma’ale Adumim, east of Jerusalem, 0.83 inches (21 millimeters) fell within an hour. The total later reached about 0.98 inches (25 millimeters), an exceptionally high amount for August.
Israel’s record for rainfall during a single August event could now also be broken. The current record is 1.3 inches (33 millimeters), measured at Kfar Galim, near Haifa, on Aug. 3, 1971. Based on current forecasts and the expected development of the weather system, forecasters say that record could also fall.
Another unusual feature is the geographic extent of the expected rainfall. Unlike isolated, localized summer showers, this system is forecast to bring rain across a broad area, stretching from northern Israel through the coastal plain and central Israel to the northern Negev. Rainfall on such a scale in late August is considered unprecedented.
Forecast highs and lows Thursday: Jerusalem 91-73 F (33-23 C), Tel Aviv 90-77 F (32-25 C), Haifa 88-75 F (31-24 C), Safed 93-73 F (34-23 C), Katzrin 100-72 F (38-22 C), Tiberias 100-75 F (38-24 C), Nazareth 97-73 F (36-23 C), Afula 99-73 F (37-23 C), Beit She’an 106-79 F (41-26 C), Lod 91-75 F (33-24 C), Ashdod 90-75 F (32-24 C), Ein Gedi 104-86 F (40-30 C), Be'er Sheva 97-73 F (36-23 C), Mitzpe Ramon 97-75 F (36-24 C) and Eilat 109-88 F (43-31 C).