Boulder County, CO: Current UV Index and Hourly Forecast

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As of 3:54 PM MDT on June 4, 2026, out of 31 cities in Boulder County, CO in our database, 26 cities (84%) have a UV Index reading of Moderate, 4 cities (13%) have a UV Index reading of High, while 1 city (3%) have a UV Index reading of Very High. The city with the highest UV Index reading right now is Longmont, CO with a reading of 7.5.

Over the next 24 hours, the highest UV Index reading in Boulder County, CO is expected to be 10.9 in Nederland between 1:00 PM - 2:00 PM MDT tomorrow.

Search Cities in Boulder County, CO

Current UV Index in Cities in Boulder County, CO

• Allenspark - 5
• Altona - 5.8
• Bark Ranch - 4.9
• Bonanza Mountain Estates - 4.9
• Boulder - 4.6
• Crisman - 4.6
• Eldora - 4.9
• Eldorado Springs - 4.6
• Gold Hill - 4.9
• Gunbarrel - 4.6
• Hidden Lake - 4.9
• Jamestown - 4.9
• Lafayette - 6.2
• Lazy Acres - 4.6
• Leyner - 6.2
• Longmont - 7.5
• Louisville - 4.6
• Lyons - 5.8
• Mountain Meadows - 4.9
• Nederland - 4.9
• Niwot - 4.6
• Paragon Estates - 4.6
• Pine Brook Hill - 4.6
• Seven Hills - 4.6
• St. Ann Highlands - 4.9
• Sugarloaf - 4.9
• Sunshine - 4.6
• Superior - 4.6
• Tall Timber - 4.6
• Valmont - 4.6
• Ward - 4.9