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
May brings a rise in Rock Valley's average high-temperature, moving from a refreshing 56.3°F (13.5°C) in April to an agreeable 68.5°F (20.3°C). May nights are marked by an average low-temperature of 51.1°F (10.6°C).Humidity
In May, the average relative humidity in Rock Valley is 69%.Rainfall
In May, in Rock Valley, the rain falls for 17.9 days. Throughout May, 3.35" (85mm) of precipitation is accumulated. Throughout the year, there are 130 rainfall days, and 24.09" (612mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, October through December. May is the last month it regularly snows in Rock Valley. During 0.3 snowfall days, in May, Rock Valley aggregates 0.24" (6mm) of snow. In Rock Valley, during the entire year, snow falls for 49.2 days and aggregates up to 19.41" (493mm) of snow.Daylight
The average length of the day in May in Rock Valley is 14h and 42min.On the first day of May, sunrise is at 6:17 am and sunset at 8:27 pm. On the last day of the month, sunrise is at 5:48 am and sunset at 8:57 pm CDT.
Sunshine
In May, the average sunshine is 8.8h.UV index
The average daily maximum UV index in May in Rock Valley is 5. A UV Index reading of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for ordinary individuals.Note: A maximum high UV index of 5 in May translates into the following recommendations:
Prioritize safety - The need to safeguard skin and eyes from harm is emphasized. Considering the Sun's intensity during midday, it's wise to minimize direct exposure. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Be mindful! The reflection from snow can increase the Sun's UV radiation nearly twice.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are May temperatures in Rock Valley?
What is the average humidity in May in Rock Valley?
How much does it rain in Rock Valley in May?
What is the last month it snows in Rock Valley?
What is the average length of the day in May in Rock Valley?
What time are sunrise and sunset in May in Rock Valley?
How many hours of sunshine does Rock Valley have in May?
What is the UV index intensity in May in Rock Valley?
Average temperature in May
Rock Valley, IA
- Average high temperature in May: 68.5°F
The warmest month (with the highest average high temperature) is July (81.9°F).
The month with the lowest average high temperature is January (24.1°F).
- Average low temperature in May: 51.1°F
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (10.8°F).
Average pressure in May
Rock Valley, IA
- Average pressure in May: 29.92"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in May
Rock Valley, IA
- Average wind speed in May: 9.6mph
The windiest month (with the highest average wind speed) is April (11.2mph).
The calmest month (with the lowest average wind speed) is July (7.8mph).
Average humidity in May
Rock Valley, IA
- Average humidity in May: 69%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is October (67%).
Average rainfall in May
Rock Valley, IA
- Average rainfall in May: 3.35"
The wettest month (with the highest rainfall) is June (3.78").
The driest month (with the least rainfall) is January (0.75").
Average rainfall days in May
Rock Valley, IA
- Average rainfall days in May: 17.9 days
The month with the highest number of rainy days is June (18.8 days).
The month with the least rainy days is February (3.3 days).
Average snowfall in May
Rock Valley, IA
- Average snowfall in May: 0.24"
The month with the highest snowfall is February (4.49").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in May
Rock Valley, IA
- Average snowfall days in May: 0.3 days
The month with the highest number of snowfall days is January (11.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Rock Valley, IA
- Average daylight in May: 14h and 4min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in May: 8h and 5min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in May
Rock Valley, IA
- Average sunshine days in May: 11.2 days
The month with the most sunshine days is November (19.7 days).
The month with the least sunshine days is June (8.3 days).
Average UV index in May
Rock Valley, IA
- Average UV index in May: 5
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, February, October, November and December (UV index 2).
Average cloud cover in May
Rock Valley, IA
- Average cloud cover in May: 41
The month with the most cloud cover is January (Cloud cover 55).
The month with the least cloud cover is July (Cloud cover 27).
Average visibility in May
Rock Valley, IA
- Average visibility in May: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
Rock Valley, Iowa, USA
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