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 shift from April to May sees an increase in the average high-temperature, transitioning from a mild 58.8°F (14.9°C) to a pleasant 69.4°F (20.8°C). The average temperature during May nights is registered at a fresh 52.9°F (11.6°C).Humidity
In Portsmouth, the average relative humidity in May is 73%.Rainfall
In May, in Portsmouth, the rain falls for 15.7 days. Throughout May, 2.6" (66mm) of precipitation is accumulated. Throughout the year, in Portsmouth, there are 113.5 rainfall days, and 15.71" (399mm) of precipitation is accumulated.Snowfall
January through May, October through December are months with snowfall. May is the last month it regularly snows in Portsmouth. During 0.3 snowfall days, in May, Portsmouth aggregates 0.16" (4mm) of snow. Throughout the year, there are 31.5 snowfall days, and 7.13" (181mm) of snow is accumulated.Daylight
The average length of the day in May in Portsmouth, Iowa, is 14h and 33min.On the first day of the month, sunrise is at 6:17 am and sunset at 8:20 pm. On the last day of May, sunrise is at 5:50 am and sunset at 8:49 pm CDT.
Sunshine
In Portsmouth, the average sunshine in May is 8.8h.UV index
In May, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for average individuals.Note: In May, the maximum UV index of 5 suggests this advice:
Undertake precautions - It is suggested to shield oneself from sunburn. Considering the harmful UV rays from the Sun during midday, it's essential to reduce exposure. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear. Forewarned is forearmed! The Sun's UV radiation can be almost doubled in intensity by snow reflection.
Frequently asked questions
What are May temperatures in Portsmouth?
What is the average humidity in May in Portsmouth?
How many days does it rain in May in Portsmouth?
What is the last month it snows in Portsmouth?
What is the average length of the day in May in Portsmouth?
What time are sunrise and sunset in May in Portsmouth?
How many hours of sunshine does Portsmouth have in May?
What is the UV index reading in May in Portsmouth?
Average temperature in May
Portsmouth, IA
- Average high temperature in May: 69.4°F
The warmest month (with the highest average high temperature) is July (82.6°F).
The month with the lowest average high temperature is January (27.3°F).
- Average low temperature in May: 52.9°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (14.5°F).
Average pressure in May
Portsmouth, 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 (29.87"Hg).
Average wind speed in May
Portsmouth, IA
- Average wind speed in May: 9.3mph
The windiest month (with the highest average wind speed) is April (10.9mph).
The calmest month (with the lowest average wind speed) is July (7.2mph).
Average humidity in May
Portsmouth, IA
- Average humidity in May: 73%
The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is October (68%).
Average rainfall in May
Portsmouth, IA
- Average rainfall in May: 2.6"
The wettest month (with the highest rainfall) is June (2.64").
The driest month (with the least rainfall) is January (0.43").
Average rainfall days in May
Portsmouth, IA
- Average rainfall days in May: 15.7 days
The month with the highest number of rainy days is June (16.1 days).
The month with the least rainy days is February (2.8 days).
Average snowfall in May
Portsmouth, IA
- Average snowfall in May: 0.16"
The month with the highest snowfall is February (2.09").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in May
Portsmouth, IA
- Average snowfall days in May: 0.3 days
The month with the highest number of snowfall days is January (8.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Portsmouth, IA
- Average daylight in May: 14h and 4min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in May: 8h and 5min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 30min).
Average sunshine days in May
Portsmouth, IA
- Average sunshine days in May: 12.8 days
The month with the most sunshine days is December (21.6 days).
The month with the least sunshine days is June (11.4 days).
Average UV index in May
Portsmouth, IA
- Average UV index in May: 5
The months with the highest UV index are June, July and August (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
Portsmouth, IA
- Average cloud cover in May: 40
The month with the most cloud cover is January (Cloud cover 52).
The month with the least cloud cover is July (Cloud cover 27).
Average visibility in May
Portsmouth, IA
- Average visibility in May: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Portsmouth, Iowa, USA
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