Weather It Is (Winter Storm Watch)

Good Afternoon:

The latest forecasts still show a lot of uncertainty, especially from Monday into Thursday.

But, first let's deal with the rest of the day through Sunday.

We're at the end of our mild winter temperatures.  Tonight will see some gusty winds and chill begin to settle in over our country and surroundings.

Rain showers should arrive Friday evening (along the sea coast) and continue off and on through Shabbat.  On Shabbat, winds will increase in intensity and they will reach gale force Sunday morning.
Snow will accumulate lightly on the Hermon.

The Global Ensemble still shows a range of possible rainfall amounts, but the potential is quite large (and will depend on the extent of cooling -- in part -- at 500 mb).  Extrapolating to forecast amounts from our high resolution models suggests that greater than 100 mm will fall in many locations from Shabbat into possibly next Thursday.

Right now, forecast temperatures for late Saturday night and Sunday morning could produce a coating of wet snow in Gush Etzion and the higher peaks surrounding Jerusalem and the mountain peaks of the Galilee. Unlike the previous storm when temperatures will warm by morning, temperatures may not warm during the day Sunday. There is a 15% chance that it will snow and accumulate in Jerusalem too.

After a brief warm-up at 500 mb late Sunday, temperatures should fall into Monday.  The average forecast 500 mb temperatures for Monday into Wednesday are about -27C.  However, averages are a bit deceiving because of the large variability among ensemble members.  There is a 30% chance for burst of heavy snow during the period as temperatures may fall as low as -30 C.

Based on the latest data, I would estimate that there is a high probability of wet snow in Jerusalem and surrounding Jerusalem peaks, but only a 30% chance that it will accumulate.  In Gush Etzion and other similarly high areas, the probability of periods of snow are very high and accumulation at 50%.

Although the chances are low for a heavy snow event in Jerusalem: the potential exists given the cold temperatures displayed on some of the ensemble members and the copious amounts of precipitation.

We know more than we did a few days ago, but we're hoping for even greater clarity tomorrow (and certainly Motzei Shabbat).

Barry Lynn