Sleep happens in cycles that include three non-rapid eye movement (NREM) stages and one rapid eye movement (REM) stage, repeated 4 to 5 times nightly. Each cycle typically lasts 90 to 110 minutes. The ...

DENVER — Clouds are thickening up ahead of some light mountain snow for Thursday morning. While totals will be light, there could be some mountain road impacts. Impacts will be fairly limited, though ...