Sunrise Forecast for Boulder

The best sunrises occur when scattered clouds catch the early light. Find a spot with a clear eastern horizon and arrive at least 20 minutes before sunrise to watch the colors develop. Mornings after a cold front often produce the most vivid skies. Use Alpenglow's quality forecast to check which days have the best conditions.

Today's sunset in Boulder is at 5:01 PM, with full darkness arriving at 6:26 PM (Australia/Perth). The period between sunset and full darkness is twilight, when the sky gradually transitions from light to dark.

Twilight typically lasts between 70 and 100 minutes from sunset to full darkness. It consists of three phases: civil twilight (brightest, about 30 minutes), nautical twilight (medium, about 30 minutes), and astronomical twilight (dimmest, about 30 minutes). The exact duration depends on latitude and the time of year — twilight is longer at higher latitudes and around the solstices.

The earliest sunrise in Boulder in 2026 is at 4:44 AM on December 4 (Australia/Perth). This occurs around the summer solstice when days are longest.