* WHAT. Sub-freezing temperatures as low as 31 possible. * WHERE. Fort Collins, and Boulder and the western suburbs of Denver. * WHEN. From late Tuesday night through Wednesday morning. * IMPACTS. Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. * ADDITIONAL DETAILS. Winds have diminished this evening below warning criteria across the adjacent plains. Nearest the foothills along the Front Range may see wind gusts 40-50 mph overnight through 3 AM.

* WHAT. Sub-freezing temperatures as low as 29 possible. * WHERE. Denver, Castle Rock, Briggsdale, Greeley, Fort Morgan, Byers, Limon, Southern Lincoln County, Sterling, and Akron. * WHEN. From late Tuesday night through Wednesday morning. * IMPACTS. Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing.

* WHAT. West winds 30 to 40 mph with gusts up to 60 mph expected. * WHERE. Banner, Kimball, and Scotts Bluff County in the Nebraska panhandle. * WHEN. Until 6 AM MDT Tuesday. * IMPACTS. Mainly to transportation. Strong cross winds will be hazardous to light weight or high profile vehicles, including campers and tractor trailers.