May weather forecastGrand River, IA
May
Weather in May
May, the last month of the spring in Grand River, is a pleasant month, with temperature in the range of an average low of 53.1°F (11.7°C) and an average high of 69.4°F (20.8°C).Temperature
As April transitions into May, a change in temperatures is observed, with average highs moving from a mild 60.4°F (15.8°C) to a pleasant 69.4°F (20.8°C). Grand River records a steady low-temperature average of 53.1°F (11.7°C) during May.Humidity
The average relative humidity in May is 81%.Rainfall
In Grand River, during May, the rain falls for 17.2 days and regularly aggregates up to 2.8" (71mm) of precipitation. Throughout the year, there are 132.4 rainfall days, and 20.24" (514mm) of precipitation is accumulated.Snowfall
January through May, October through December are months with snowfall in Grand River, Iowa. May is the last month it regularly snows. During 0.2 snowfall days, in May, Grand River aggregates 0.2" (5mm) of snow. In Grand River, during the entire year, snow falls for 30.2 days and aggregates up to 10.16" (258mm) of snow.Daylight
In Grand River, the average length of the day in May is 14h and 29min.On the first day of the month, sunrise is at 6:13 am and sunset at 8:12 pm. On the last day of May, sunrise is at 5:46 am and sunset at 8:40 pm CDT.
Sunshine
In May, the average sunshine is 8.6h.UV index
In May, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for the average person.Note: A maximum high daily UV index of 5 during May translates into the following directions:
Put precautions into practice - Ensuring skin and eye safety is a necessity. Avoiding direct sun during mid-day hours can prevent harmful UV radiation exposure. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck. Remember to consider! The UV radiation from the Sun can be intensified nearly twice by the reflection of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Grand River, IA
- Average high temperature in May: 69.4°F
The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is January (30.6°F).
- Average low temperature in May: 53.1°F
The month with the highest average low temperature is July (66°F).
The coldest month (with the lowest average low temperature) is January (16.9°F).
Average pressure in May
Grand River, 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
Grand River, IA
- Average wind speed in May: 8.6mph
The windiest months (with the highest average wind speed) are January, February and March (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (6.9mph).
Average humidity in May
Grand River, IA
- Average humidity in May: 81%
The month with the highest relative humidity is June (83%).
The month with the lowest relative humidity is October (72%).
Average rainfall in May
Grand River, IA
- Average rainfall in May: 2.8"
The wettest month (with the highest rainfall) is June (3.43").
The driest months (with the least rainfall) are January and December (0.67").
Average rainfall days in May
Grand River, IA
- Average rainfall days in May: 17.2 days
The month with the highest number of rainy days is June (17.3 days).
The month with the least rainy days is January (4.8 days).
Average snowfall in May
Grand River, IA
- Average snowfall in May: 0.2"
The month with the highest snowfall is January (2.72").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in May
Grand River, IA
- Average snowfall days in May: 0.2 days
The month with the highest number of snowfall days is January (8.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Grand River, IA
- Average daylight in May: 14h and 30min
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 18min).
- Average sunshine in May: 8h and 36min
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 24min).
Average sunshine days in May
Grand River, IA
- Average sunshine days in May: 10.8 days
The month with the most sunshine days is December (20.3 days).
The month with the least sunshine days is June (8.9 days).
Average UV index in May
Grand River, 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
Grand River, IA
- Average cloud cover in May: 41
The month with the most cloud cover is January (Cloud cover 51).
The month with the least cloud cover is July (Cloud cover 28).
Average visibility in May
Grand River, 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).





