UWFPS 2017 daily cold-air pool forecast valid Tuesday 1/24/2017  11:00 am MST

Summary: Periods of light snow will continue through Wednesday as temperatures cool. A ridge of high pressure will begin to build over Utah on Friday and continue through early next week, setting the stage for a poor air quality episode.

Current weather outlook for Tuesday 24 January - Wednesday 1 February. 

Highs will range from the teens to 20s (colder in Cache Valley) with lows from zero to the teens through Monday.

Tuesday 24 January Colder. Scattered snow showers. Light accumulation possible (1") Tuesday evening.

Wednesday 25 January Cloudy, cold.  Scattered light snow showers.

Thursday 26 January Mostly cloudy, cold. Slight chance of snow. Potential "non-inversion" day with no flight visibility restrictions.

Friday 27 January Partly cloudy, cold.  Cold-air pool start currently forecast for Friday early morning.

Saturday 28 January - Wednesday 1 February.

The following ingredients will be in place for basin persistent cold-air pools in Utah Friday through at least Monday:

Snow cover across the region (22" depth in Cache, 3-8" depth in Utah and Salt Lake Valleys).

Cold-air emplacement prior to cold-air pool (daytime surface temperatures will fall to around 22 degrees F by Thursday

Temperatures will warm at mountaintop level from -16 C on Thursday to -2 C on Sunday, resulting in a capping temperature inversion.   

Thus, persistent cold-air pool conditions are likely through at least Monday.  Models are producing some fog with strong nocturnal cooling, so this will need to be monitored closely for flight operations. Uncertainty remains regarding the intensity and longevity of the cold-air pool in the Sunday-Wednesday time period, and when a mix-out will occur. Stay tuned.

ECMWF Ensemble 500 hPa Heights forecast 1200 UTC Sunday. Note the large high pressure ridge over the Western US