Weather It Is (Heavy Snow Warning)

Good Evening:

The cold weather came in as forecast (Thank God), and turned the rain to snow in the higher elevations of the Galilee, Jerusalem, and Gush Etzion by early Thursday morning.  The cold will deepen tonight over the northeastern Mediterranean sea and the upper level trough (at 500 mb) will then move slowly southeastward during the day. As it does so, temperatures will drop at upper levels here, and this will strengthen a low pressure at the surface that will should bury today's snow under an even heavier snowfall late Friday and Friday night.

Between 50 to 100 mm of precipitation amounts are forecast for the central coast and central mountains.  Lesser amounts of precipitation will occur over the north and south, but still potentially cause flooding in low lying areas.

Most importantly, with the cold entrenched, this just might translate into greater than 50 cm of snow in the central mountains.  One might expect that the warm sea might hold down snow amounts by warming the lower atmosphere.  However, the cold is deep enough to take advantage of the copious amounts of moisture evaporating off the warm sea, transported upwards into the atmosphere and deposited as snow over the mountains.  So, this is an unusual situation: we have the precipitation amounts of an early season storm, but the cold of January.

The timeline and a couple of notes. Snow will be heavy at times tonight and tomorrow morning, accumulating around 25 cm by mid-day Friday.  Late in the afternoon, the snow will become even heavier, with possible white-out conditions, and accumulate between 25 and 50 cm more by Saturday morning.

The snow will taper off during the day, and the storm will be gone by Sunday, and be followed by a period of more tranquil weather.

Note 1: We're investigating some predictions for unusually cold temperatures. This is happening in areas covered with snow, but we don't think it realistic.

Note 2: My daughter would like some credit for the snow.  She asked me a few weeks ago if it could snow at Chanukah.  I said it could, but it wasn't likely (as Chanukah this year was  rather early in the season).  Sometimes, to succeed, one must simply ask a questions.

Barry Lynn