Contents
- Weather in May
- Frequently asked questions
- Average temperature in May
- Average pressure in May
- Average wind speed in May
- Average humidity in May
- Average rainfall in May
- Average rainfall days in May
- Average snowfall in May
- Average snowfall days in May
- Average daylight in May
- Average sunshine in May
- Average sunshine days in May
- Average UV index in May
- Average cloud cover in May
- Average visibility in May
Weather in May
Temperature
The start of May brings a rise in the average high-temperature, moving from a cool 54°F (12.2°C) in April to a comfortable 65.8°F (18.8°C). May nights are marked by an average low-temperature of 47.8°F (8.8°C).Humidity
In May, the average relative humidity is 81%.Rainfall
In Dorchester, during May, the rain falls for 17.3 days and regularly aggregates up to 3.54" (90mm) of precipitation. Throughout the year, there are 130.5 rainfall days, and 26.5" (673mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, October through December. May is the last month it regularly snows. During 0.3 snowfall days, in May, Dorchester aggregates 0.2" (5mm) of snow. Throughout the year, there are 51.4 snowfall days, and 22.2" (564mm) of snow is accumulated.Daylight
The average length of the day in May is 14h and 43min.On the first day of the month, sunrise is at 5:57 am and sunset at 8:08 pm. On the last day of May, sunrise is at 5:28 am and sunset at 8:39 pm CDT.
Sunshine
In Dorchester, the average sunshine in May is 8.4h.UV index
The average daily maximum UV index in May is 5. A UV Index estimate of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: A daily high UV index of 5 in May leads to these guidelines:
Heed the precautions - Suggestions to avoid sunburn are made. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. During bright days, sunglasses that offer UVA and UVB defense are recommended. Note well! The intensity of the Sun's UV rays can be nearly doubled by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in May?
What is the average humidity in May?
How much does it rain in May?
What is the last month it snows in Dorchester?
What is the average length of the day in May?
When is the sunrise / sunset in May?
How long on average sun shines in May?
What is the UV index reading in May?
Average temperature in May
Dorchester, IA
- Average high temperature in May: 65.8°F
The warmest month (with the highest average high temperature) is July (79.3°F).
The month with the lowest average high temperature is January (21.7°F).
- Average low temperature in May: 47.8°F
The month with the highest average low temperature is July (61.3°F).
The coldest month (with the lowest average low temperature) is January (8.8°F).
Average pressure in May
Dorchester, IA
- Average pressure in May: 29.94"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in May
Dorchester, IA
- Average wind speed in May: 8.2mph
The windiest month (with the highest average wind speed) is April (9.6mph).
The calmest months (with the lowest average wind speed) are July and August (6.5mph).
Average humidity in May
Dorchester, IA
- Average humidity in May: 81%
The month with the highest relative humidity is January (90%).
The month with the lowest relative humidity is October (76%).
Average rainfall in May
Dorchester, IA
- Average rainfall in May: 3.54"
The wettest month (with the highest rainfall) is June (4.61").
The driest month (with the least rainfall) is January (0.87").
Average rainfall days in May
Dorchester, IA
- Average rainfall days in May: 17.3 days
The month with the highest number of rainy days is June (18 days).
The month with the least rainy days is February (3 days).
Average snowfall in May
Dorchester, IA
- Average snowfall in May: 0.2"
The month with the highest snowfall is February (5.71").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in May
Dorchester, IA
- Average snowfall days in May: 0.3 days
The month with the highest number of snowfall days is January (12 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Dorchester, IA
- Average daylight in May: 14h and 4min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in May: 8h and 2min
The month with the most sunshine is August (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 24min).
Average sunshine days in May
Dorchester, IA
- Average sunshine days in May: 11.2 days
The month with the most sunshine days is January (17.7 days).
The month with the least sunshine days is June (9.8 days).
Average UV index in May
Dorchester, IA
- Average UV index in May: 5
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 1).
Average cloud cover in May
Dorchester, IA
- Average cloud cover in May: 45
The month with the most cloud cover is January (Cloud cover 65).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility in May
Dorchester, IA
- Average visibility in May: 6mi
The months with the highest visibility are April, May, June, October and November (6mi).
The months with the lowest visibility are January, February, March, July, August, September and December (5mi).
Dorchester, Iowa, USA
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