After enduring frigid, Arctic air for much of the past week, Colorado's Front Range urban corridor is about to be rescued by a down-sloping, southwest wind. Actually, the wind shift developed early this morning as the cold, low pressure trough pushed off to the east and a dome of high pressure developed over the American Southwest.
While the effect of this wind shift was visually evident today, scouring the haze from the Piedmont and producing crystal-clear views of the Front Range peaks, a persistent cloud deck limited the warming effect of the downslope flow and afternoon highs topped out in the low 30s (F). Produced by the pressure gradient between high pressure to our southwest and low pressure to our ENE, the southwesterly winds compress, dry out and heat up as they descend from the Continental Divide and, over the next few days, will produce sunny skies with afternoon temperatures in the fifties. In fact, our overnight lows will be 2-3 times the Fahrenheit value of our recent afternoon highs.
Meanwhile, west of the Divide, these same winds are up-sloping and the Arctic chill persists; while Metro Denver basked in 30 degree heat this afternoon, Grand Junction shivered in the single digits. By contrast, when upslope snowstorms strike the Front Range corridor in March and April, the cities on the western slope receive a downslope flow and enjoy sunny, warm conditions.
