See it? Crescent moon at sunset: 15 percent illuminated.
Standing-wave cloud over The Rockies at sunset.
Lenticular clouds over Boulder, Colo. Rocky Mountain sunset.
Iridescent cloud parked over Boulder, Colo., at sunset.
Long, bright wave-cloud sunset over Colorado.
A rain-snowbow with lenticular clouds.
Source: NWS, Boulder / Denver
Orange glow paints the Rocky Mountains of Colorado.
Sun setting right over the city of Boulder.
Lenticular clouds at sunset.
‘Hovering” over the Rockies and Boulder, Colo.
Long, orange lenticular cloud at sunset over Boulder, Colo.
Lenticular clouds stacked like pancakes over Boulder, Colo.
Standing-wave cloud along the Rocky Mountains.
Filled the sky from Boulder to Denver.