This is an archived article that was published on sltrib.com in 2014, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

A high pressure system was to roll into the region late Wednesday, bringing with it a return of pollution-trapping air inversions and colder temperatures to northern Utah's urban valleys.

On Tuesday, the Utah Division of Air Quality rated the entire state as "green," or healthy for breathability. That was forecast to deteriorate considerably by late Wednesday or Thursday, though, when Salt Lake, Davis, Utah, Weber and Cache counties were down to "yellow," or moderate for air quality.

DAQ officials said that diminished air quality was likely to continue into the weekend as smog levels grew.

Colder temperatures, too, were to hit the state, despite generally sunny skies into late this week.

The Wasatch Front looked for highs in the upper-30s on Wednesday, down 3-5 degrees from Tuesday's forecast. Overnight lows will range into the teens Wednesday, again a few degrees chillier than Tuesday's lows.

While northern Utahns shivered, southern Utah will be awash in sunshine and high temperatures around 60 degrees with overnight lows in the mid-30s.

The Utah Avalanche Center predicted "high" risks for potentially deadly snowslides for the mountains above Logan and the Uintas on Wednesday; 'considerable" for Provo, Ogden and Salt Lake backcountry slopes; and "moderate" for the mountains around Moab.

For more extensive forecast information, visit the Tribune's weather page at http://www.sltrib.com/weather.

Twitter: @remims