May weather forecast
Jefferson, CO

Share

Weather in May

The last month of the spring, May, is a frosty month in Jefferson, Colorado, with an average temperature ranging between min 23.4°F (-4.8°C) and max 45.5°F (7.5°C).

Temperature

Jefferson, Colorado, sees a rise in temperature during May, with average high-temperatures transitioning from a cold 33.6°F (0.9°C) in April to a chilly 45.5°F (7.5°C). Jefferson experiences a significant reduction from daytime highs with an average low-temperature of 23.4°F (-4.8°C) in May.

Humidity

In Jefferson, the average relative humidity in May is 71%.

Rainfall

In Jefferson, during May, the rain falls for 12.3 days and regularly aggregates up to 3.23" (82mm) of precipitation. In Jefferson, Colorado, during the entire year, the rain falls for 110.4 days and collects up to 24.09" (612mm) of precipitation.

Snowfall

Months with snowfall are January through December. The month with the most snowfall is May, when snow falls for 19 days and typically aggregates up to 19.69" (500mm) of snow.

Daylight

The average length of the day in May is 14h and 22min.
On the first day of May, sunrise is at 6:03 am and sunset at 7:57 pm. On the last day of the month, sunrise is at 5:38 am and sunset at 8:23 pm MDT.

Sunshine

In Jefferson, the average sunshine in May is 9.9h.

UV index

The months with the highest UV index are May through August, with an average maximum UV index of 3. A UV Index reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the ordinary person.
Note: The maximum UV index of 3 during May translates into these guidelines:
Take necessary precautions - Protection from skin and eye injury is mandatory. Being exposed to the midday Sun can have harmful effects due to strong UV radiation; always take precautions. By wearing a generously brimmed hat, you can cut UV radiation exposure significantly. Observe! Snow reflection can nearly intensify the Sun's UV radiation twofold.
Updated: Jul 12, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are the temperatures in May?

The high-temperature during May is 45.5°F (7.5°C) and the low-temperature is 23.4°F (-4.8°C).

What is the average humidity in May?

In May, the average relative humidity is 71%.

How many days does it rain in May?

In Jefferson, in May, during 12.3 rainfall days, 3.23" (82mm) of precipitation is typically accumulated.

When does it snow the most?

May is the month with the most snowfall in Jefferson. Snow falls for 19 days and accumulates 19.69" (500mm) of snow.

How much does it snow in May?

In May, it is snowing for 19 days. Throughout May, 19.69" (500mm) of snow is accumulated.

How many hours of daylight does Jefferson have in May?

In May, the average day length is 14h and 22min.

When is the sunrise / sunset in May?

On the first day of May, sunrise is at 6:03 am and sunset at 7:57 pm. On the last day of the month, sunrise is at 5:38 am and sunset at 8:23 pm MDT.

How many hours of sunshine does Jefferson have in May?

In Jefferson, the average sunshine duration in May is 9.9h.

What are the months with the highest UV index?

May through August, with an average maximum UV index of 3, are months with the highest UV index.

What is the UV index intensity in May?

The average daily maximum UV index in May is 3. A UV Index estimate of 3 to 5 represents a moderate health threat from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in May
Jefferson, CO

Average temperature in May - Jefferson, CO
  • Average high temperature in May: 45.5°F

The warmest month (with the highest average high temperature) is July (65.8°F).
The month with the lowest average high temperature is December (21.2°F).

  • Average low temperature in May: 23.4°F

The month with the highest average low temperature is July (40.1°F).
The coldest months (with the lowest average low temperature) are January and December (0.7°F).

Average pressure in May
Jefferson, CO

Average pressure in May - Jefferson, CO
  • Average pressure in May: 29.94"Hg

The month with the highest atmospheric pressure is January (30.19"Hg).
The months with the lowest atmospheric pressure are April and May (29.94"Hg).

Average wind speed in May
Jefferson, CO

Average wind speed in May - Jefferson, CO
  • Average wind speed in May: 6.1mph

The windiest month (with the highest average wind speed) is February (7mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).

Average humidity in May
Jefferson, CO

Average humidity in May - Jefferson, CO
  • Average humidity in May: 71%

The month with the highest relative humidity is February (89%).
The month with the lowest relative humidity is June (54%).

Average rainfall in May
Jefferson, CO

Average rainfall in May - Jefferson, CO
  • Average rainfall in May: 3.23"

The wettest month (with the highest rainfall) is July (3.35").
The driest month (with the least rainfall) is November (1.14").

Average rainfall days in May
Jefferson, CO

Average rainfall days in May - Jefferson, CO
  • Average rainfall days in May: 12.3 days

The month with the highest number of rainy days is July (22.8 days).
The month with the least rainy days is November (2.8 days).

Average snowfall in May
Jefferson, CO

Average snowfall in May - Jefferson, CO
  • Average snowfall in May: 19.69"

The month with the highest snowfall is May (19.69").
The month with the least snowfall is July (0.24").

Average snowfall days in May
Jefferson, CO

Average snowfall days in May - Jefferson, CO
  • Average snowfall days in May: 19 days

The month with the highest number of snowfall days is April (22.8 days).
The month with the least snowfall days is July (1.3 days).

Average daylight in May /
Average sunshine in May
Jefferson, CO

Average daylight in May / Average sunshine in May - Jefferson, CO
  • Average daylight in May: 14h and 2min

The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).

  • Average sunshine in May: 9h and 5min

The month with the most sunshine is June (Average sunshine: 11h and 24min).
The month with the least sunshine is February (Average sunshine: 5h and 12min).

Average sunshine days in May
Jefferson, CO

Average sunshine days in May - Jefferson, CO
  • Average sunshine days in May: 7.5 days

The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is July (5.8 days).

Average UV index in May
Jefferson, CO

Average UV index in May - Jefferson, CO
  • Average UV index in May: 3

The months with the highest UV index are May, June, July and August (UV index 3).
The months with the lowest UV index are February and December (UV index 1).

Average cloud cover in May
Jefferson, CO

Average cloud cover in May - Jefferson, CO
  • Average cloud cover in May: 36

The month with the most cloud cover is February (Cloud cover 54).
The month with the least cloud cover is June (Cloud cover 19).

Average visibility in May
Jefferson, CO

Average visibility in May - Jefferson, CO
  • Average visibility in May: 5mi

The months with the highest visibility are June, July, August, September and October (6mi).
The months with the lowest visibility are January, February, March, April and December (4mi).

Jefferson, Colorado, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location