How Long Will it Last?

For the first week in January, Star Valley is enjoying beautiful weather.  Temperatures Tuesday afternoon were above freezing in all areas of the valley.  The strong temperature inversion which has been present much of the past month was still in place Tuesday with the coldest maximum of 32 at Etna, while at Salt River Summit the high temperature was 48 at an elevation, 2000 feet higher than Etna.

There should be two more days of exemplary conditions as high pressure covers the area.

The upper high pressure ridge remains strong as the model shows for Wednesday evening.

500mb Forecast Wednesday Evening 1/4/12

By Friday the ridge temporarily breaks down allowing a rather weak upper low pressure trough to cross Idaho/Wyoming.

500 mb Forecast Friday evening 01/6/2012

And then by the end of the weekend the upper high pressure ridge again moves toward our area.

500 mb Forecast Sunday Evening 01/08/12

By Friday cloudiness and scattered snow showers will spread across the region with the passage of the weak upper trough.  However this should result in generally insignificant snow totals at best in the valley and possibly a few inches in the higher elevations.

The model forecast total precipitation through the coming weekend suggest the same outcome.

Total precipitation forecast Thursday-Sunday

The Climate Prediction Center of NOAA in their forecast for the month of January issued on 12/31/2011 suggests that the high pressure will break down and lead to more favorable conditions for significant snows.

For at least the first week of January this will not be the case and time will tell how accurate this forecast will be for the remainder of the month.