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
As May arrives, Grinnell's weather shows an increase in high-temperatures, moving from April's refreshing 58.5°F (14.7°C) to an agreeable 69.3°F (20.7°C). An average low-temperature of 52.3°F (11.3°C) is noted during the month of May.Humidity
In May, the average relative humidity in Grinnell is 78%.Rainfall
The wettest months are May and June, with an average 1.97" (50mm) of rainfall.Snowfall
Months with snowfall in Grinnell are January through May, October through December. May is the last month it regularly snows. During 0.2 snowfall days, in May, Grinnell aggregates 0.2" (5mm) of snow. In Grinnell, during the entire year, snow falls for 30.7 days and aggregates up to 6.06" (154mm) of snow.Daylight
In Grinnell, the average length of the day in May is 14h and 34min.On the first day of the month, sunrise is at 6:06 am and sunset at 8:09 pm. On the last day of May, in Grinnell, Iowa, sunrise is at 5:38 am and sunset at 8:38 pm CDT.
Sunshine
The average sunshine in May is 8.7h.UV index
In Grinnell, Iowa, the average daily maximum UV index in May is 5. A UV Index value of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV rays for ordinary individuals.Note: In May, the UV index of 5 transforms into the following advice:
Act with care - Obligation to protect against skin and eye damage is highlighted. The Sun is at its harshest during midday; protect yourself by staying in shaded areas and minimizing exposure. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Notice this! Nearly double the intensity of the Sun's UV radiation can be caused by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are May temperatures in Grinnell?
What is the average humidity in May in Grinnell?
What is the wettest month in Grinnell?
How much does it rain in Grinnell in May?
What is the last month it snows in Grinnell?
How many hours of daylight does Grinnell have in May?
When is the sunrise / sunset in May in Grinnell?
How many hours of sunshine does Grinnell have in May?
How high is the UV index in May in Grinnell?
Average temperature in May
Grinnell, IA
- Average high temperature in May: 69.3°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (27°F).
- Average low temperature in May: 52.3°F
The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (13.8°F).
Average pressure in May
Grinnell, IA
- Average pressure in May: 29.93"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in May
Grinnell, IA
- Average wind speed in May: 9.1mph
The windiest month (with the highest average wind speed) is April (10.7mph).
The calmest month (with the lowest average wind speed) is August (7mph).
Average humidity in May
Grinnell, IA
- Average humidity in May: 78%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is October (71%).
Average rainfall in May
Grinnell, IA
- Average rainfall in May: 1.97"
The wettest months (with the highest rainfall) are May and June (1.97").
The driest month (with the least rainfall) is January (0.47").
Average rainfall days in May
Grinnell, IA
- Average rainfall days in May: 14.6 days
The month with the highest number of rainy days is June (15.1 days).
The month with the least rainy days is February (4.1 days).
Average snowfall in May
Grinnell, IA
- Average snowfall in May: 0.2"
The month with the highest snowfall is January (1.81").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in May
Grinnell, IA
- Average snowfall days in May: 0.2 days
The month with the highest number of snowfall days is January (8.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Grinnell, IA
- Average daylight in May: 14h and 4min
The month with the longest days is June (Average daylight: 15h and 12min).
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 12min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in May
Grinnell, IA
- Average sunshine days in May: 13.5 days
The month with the most sunshine days is January (21.1 days).
The month with the least sunshine days is June (11.5 days).
Average UV index in May
Grinnell, IA
- Average UV index in May: 5
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in May
Grinnell, IA
- Average cloud cover in May: 42
The month with the most cloud cover is January (Cloud cover 55).
The month with the least cloud cover is September (Cloud cover 29).
Average visibility in May
Grinnell, 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).
Grinnell, Iowa, USA
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