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
Altoona's weather shows a temperature rise with the arrival of May, moving from a refreshing 59.5°F (15.3°C) in April to a pleasant 69.6°F (20.9°C). Throughout May, Altoona experiences a low-temperature average of 52.9°F (11.6°C).Humidity
The average relative humidity in May is 78%.Rainfall
May is the month with the most rainfall in Altoona. Rain falls for 11.6 days and accumulates 0.98" (25mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
The average length of the day in May is 14h and 33min.On the first day of May, sunrise is at 6:09 am and sunset at 8:12 pm. On the last day of the month, sunrise is at 5:41 am and sunset at 8:41 pm CDT.
Sunshine
The average sunshine in May in Altoona is 8.7h.UV index
In Altoona, the average daily maximum UV index in May is 5. A UV Index of 3 to 5 symbolizes a moderate threat to health from unprotected exposure to Sun's UV rays for the ordinary person.Note: In May, the average maximum UV index of 5 translates into the following recommendations:
Guard yourself - Avoiding sunburn is suggested. Avoiding the Sun during its peak radiation time around midday is a healthy practice. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance. 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 is the average May temperature?
What is the average humidity in May?
What is the wettest month?
How many days does it rain in May?
When it does not snow?
Does it snow in May?
How many hours of daylight does Altoona have in May?
When is the sunrise / sunset in May?
How long on average sun shines in May?
How high is the UV index in May?
Average temperature in May
Altoona, IA
- Average high temperature in May: 69.6°F
The warmest month (with the highest average high temperature) is July (82.4°F).
The month with the lowest average high temperature is January (27.5°F).
- Average low temperature in May: 52.9°F
The month with the highest average low temperature is July (65.1°F).
The coldest month (with the lowest average low temperature) is January (14.4°F).
Average pressure in May
Altoona, IA
- Average pressure in May: 29.93"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in May
Altoona, IA
- Average wind speed in May: 8.8mph
The windiest month (with the highest average wind speed) is April (10.4mph).
The calmest month (with the lowest average wind speed) is August (6.9mph).
Average humidity in May
Altoona, IA
- Average humidity in May: 78%
The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is October (70%).
Average rainfall in May
Altoona, IA
- Average rainfall in May: 0.98"
The wettest month (with the highest rainfall) is May (0.98").
The driest months (with the least rainfall) are January, February and December (0.24").
Average rainfall days in May
Altoona, IA
- Average rainfall days in May: 11.6 days
The month with the highest number of rainy days is May (11.6 days).
The month with the least rainy days is January (1.8 days).
Average snowfall in May
Altoona, IA
- Average snowfall in May: 0"
The month with the highest snowfall is January (0.91").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in May
Altoona, IA
- Average snowfall days in May: 0.1 days
The month with the highest number of snowfall days is January (6.2 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Altoona, 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 4min
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 12min).
Average sunshine days in May
Altoona, IA
- Average sunshine days in May: 16.6 days
The month with the most sunshine days is December (25.5 days).
The month with the least sunshine days is June (15.5 days).
Average UV index in May
Altoona, IA
- Average UV index in May: 5
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in May
Altoona, IA
- Average cloud cover in May: 41
The month with the most cloud cover is January (Cloud cover 54).
The months with the least cloud cover are July and September (Cloud cover 29).
Average visibility in May
Altoona, IA
- Average visibility in May: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
Altoona, Iowa, USA
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