Barry Lynn
Intersection of Science and Policy

Heavy Snow Expected in Jerusalem

A prelude to the cold to come (25 Fahrenheit in Efrat)

These are the conditions expected over the next couple of day, assuming all remains as currently forecast.

As discussed in our “Israel Winter Weather ” group, forecast conditions have trended towards both snow and extreme cold.  In areas that normally see snow during winter storms (including Jerusalem), this combination will create impassable driving conditions late Wednesday into Thursday, if not later where frozen precipitation remains on the roads. Snow accumulations are potentially between 10 and 20 cm in the Jerusalem area, depending on elevation.  Lighter snow amounts are expected in the north.

In our previous storm, the forecast trended away (towards lower probability) as we approached the storm event, leaving us with just extreme cold.  But, we’ve been watching this potential event for several days, and the trend towards a deeper 500 mb trough, and more prolonged and heavy precipitation has continued to this day (Tuesday).

Some important details: this storm should bring even colder weather than our last. More importantly, later in the afternoon and evening, high relative humidity in the “Dendritic” zone (-12 to -18 Celsius), will lead to rapid formation of large snowflakes. These snowflakes will form as moisture from the sea overruns the cold air at the surface and within the mountain ridges.  The snow will accumulate quickly, closing roads, so travel will probably be impossible from late afternoon Wednesday into Thursday. The heaviest snow should fall in the late afternoon and evening hours. The deep freeze should last into Friday morning.

Be Safe.

About the Author
Dr. Barry Lynn has a PhD in Environmental and Atmospheric Sciences. He has an undergraduate degree in Biology. He is a researcher/lecturer at the Hebrew University of Jerusalem, and is the CTO of Weather It Is, LTD, a weather forecasting and consulting company.