Boulder
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Boulder Weather in May

Boulder in May sees pleasant daytime temperatures of 21°C (70°F) and nighttime lows of 6°C (43°F). With the highest rainfall of the year it is wise to pack an umbrella and expect frequent showers.

Rainfall in Boulder in May

During the wettest month of the year, an umbrella can be your best friend to stay dry. Rain is expected on roughly 12 days, totalling around 80 mm (3.1 in) for the month. The rainfall pattern this month is fairly balanced. Showers tend to be moderate rather than extreme.

Temperature in Boulder in May

Boulder has excellent weather in May, with days reaching 21°C (70°F) and nights cooling to 6°C (43°F). Conditions are often most pleasant around the middle of the day. Nights fall to 6°C (43°F), which is cold enough to feel it indoors too. A good thick duvet makes all the difference for a comfortable night's sleep.

Sunshine in Boulder in May

The city usually sees around 290 hours of sunlight, indicating many sunny days , a great month for sightseeing.

If your ideal day consists of dry skies and pleasant temperatures, May, June and September typically offer the best circumstances for Boulder.

Boulder Temperature in May

Min Temperature
6°C (43°F)
Max Temperature
21°C (70°F)
Chance of Rain
41%
Precipitation
80 mm (3.1 in)
Rainy days
12 days
Humidity
51% *
Sunshine
290 hours *
Percentage Sunshine
65% *
* Data from: Denver, the United States of America (45 KM, 28 Miles).

Boulder Weather by Month

Pick a month to see the average temperature, rainfall and sunshine in Boulder - and find the best time to visit.

Best Places in the United States of America in May

Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in May →

perfect weather
pleasant
tolerable
unpleasant
poor

Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).

What to Wear in Boulder in May

For Boulder in May, you'll want flexible clothing. It's wise to pack cotton shirts, comfortable shorts, and a pair of jeans for cooler evenings. A light sweater or jacket is useful for air-conditioned spaces (like buses) or unexpected cool moments. Rain is likely on several days, so bring a good rain jacket. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.

What To Do in Boulder in May

We rated the following activities from 1 (least suitable) to 10 (best) to do.

  • Cycling
    9/10
  • Walking
    9/10
  • Barbeque
    8/10
  • Camping
    4/10
  • Outdoor sports
    9/10

Boulder 3-Day Forecast

Popular in May

Where to go in May - average daytime high across popular destinations.

Bucket list

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