The Weather Outside is Frightful

This is what is known in Utah as an inversion.

It happens when a high-pressure system hovers over the Wasatch Mountains and compresses cold air down upon the valley, where pollutants from automobile fumes and fireplaces are produced. When combined with these pollutant, the area fog (which forms from ice crystals in the cold air) becomes smog and takes on a brownish hue. Often the amount of pollutants in the air exceeds the EPA's health standard.

On windless days, this mixture is denser than the warmer air layer above it and thus cannot escape. So what results is a cold layer of smog under a warmer layer of air. When this occurs, the smog crystals fall out of the air throughout the day, clinging to objects and producing hoarfrost. At times, it appears to be snowing. But unlike real snow, this stuff leaves a residue.

A good snowstorm or strong wind is what is needed to restore the balance.

Usually the higher you go into the mountains, the colder the air, but during the temperature inversion, this is not the case. Conditions can be such that the valley is around ten degrees (Fahrenehit) and blanketed with a cream soup fog, while the mountain temperature is thirty-five degrees (Fahrenehit) with sunny skies. So an easy way to get a little relief from the smog and cold air is to drive up one of the canyons. Looking down into the valley from up above, the inversion looks like a layer of fluffy clouds.

Air now unhealthy for general public

January 21st, 2009 @ 11:24am

(KSL News) The air along the Wasatch Front right now is hazardous to your health.

The heavy smog that has gathered over the past few days due to the inversion has led to air quality officials to warn that the air outside is unhealthy for the general public, and not just those with health problems.

Health advisories have been put in place in Cache, Salt Lake, Davis, Utah and Weber counties warning residents to avoid heavy exertion outside.