Weather It Is (Rain, Wind, and Possible Snow)

Good Morning:

Today will see the last of the warm winter days, and Wednesday will see a chance of tropical showers across the south.   Then, temperatures will fall steadily into Shabbat. Temperatures at 850 mb will pass through freezing sometime Friday night and this will set the stage for possible mixed precipitation or wet snow in the central mountains and on the northern peaks of the Galilee.

Like yesterday, we see the coldest temperatures aloft (500 mb) on Thursday night into Friday morning, while coldest temperatures at 700 mb  -- middle atmosphere (and at 850 mb  -- lower atmosphere) should occur Friday night into Sunday night (Sunday morning).

This forecast is quite tricky because there is still a lot of variability in the range of possible temperatures, especially at 700 and 500 mb.  The latest (00 GMT) global ensemble forecast continues to hint at secondary upper trough development Friday night into Shabbat.  The Euro suggests that the main upper level support will pass through at this time.  To create good mixing and good snow formation, the atmosphere should be below -25 C at 500 mb (preferably closer to -30 C).  Right now, several forecasts indicate 500 mb around or below -25 C, but the majority do not.

In summary: a soaking rain with thunderstorms, hail and graupel likely Thursday night into Friday with gale force winds lasting into Friday night. Periods of precipitation into Sunday morning, with mixed precipitation or snow possible, depending on what side of "uncertainty" we end up.

Barry Lynn