Persistent high pressure has been parked over the Star Valley area much of December. Result has been minimal amounts of snow and rather cold temperatures. It appears now that high pressure will be around at least through Christmas Weekend. The latest model forecast indicates that pressures will be above normal over the eastern Pacific Ocean, which will in turn force the storm track far to the north into Western Canada. This graphic is centered on Christmas Day.
|Christmas Day Height Anomaly 500 mb
Red indicates above normal heights, blue below
There will be a low pressure trough that will be passing off to the northeast of Star Valley on Wednesday, Some snow is possible with this system, but again amounts should be generally light.
|500 mb forecast Wednesday December 21 2011|
The longer range forecast through the remainder of the month do not hold out much hope for a significant snow storm the rest of 2011. While travelers will favor this outcome, skiers will not be pleased.
|8-14 Day Outlook Precipitation Valid Dec 25-31 2011|
The strong temperature inversion across the valley much of December is likely to persist. This will keep nights cold, near or below zero, and afternoon highs not likely reaching freezing. At Thayne Elementary the high so far this month has only been 26.