Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
With September's onset, the weather shows a temperature decrease, transitioning from a hot 87.1°F (30.6°C) in August to a warm 75.9°F (24.4°C). In September, the average low-temperature is a mild 55.6°F (13.1°C).Humidity
The average relative humidity in September is 45%.Rainfall
In September, in Grandview, Washington, the rain falls for 5 days. Throughout September, 0.28" (7mm) of precipitation is accumulated. In Grandview, during the entire year, the rain falls for 80.1 days and collects up to 4.84" (123mm) of precipitation.Snowfall
In Grandview, snow does not fall in April through October.Daylight
In Grandview, the average length of the day in September is 12h and 31min.On the first day of September in Grandview, sunrise is at 6:21 am and sunset at 7:37 pm. On the last day of the month, sunrise is at 6:57 am and sunset at 6:40 pm PDT.
Sunshine
The average sunshine in September is 10.8h.UV index
The average daily maximum UV index in September in Grandview is 4. 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 September, a regular UV index of 4 translates into these guidelines:
Put precautions into practice - Ensuring skin and eye safety is a necessity. Avoiding the Sun's peak radiation during midday hours is essential for health and safety. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation. Be aware! The intensity of the Sun's UV radiation can be amplified nearly twice due to snow reflection.
Frequently asked questions
What are September temperatures in Grandview?
What is the average humidity in September in Grandview?
How much does it rain in Grandview in September?
When it does not snow in Grandview?
How many hours of daylight does Grandview have in September?
When are sunrise and sunset in September in Grandview?
How many hours of sunshine does Grandview have in September?
What is the UV index reading in September in Grandview?
Average temperature in September
Grandview, WA
- Average high temperature in September: 75.9°F
The warmest month (with the highest average high temperature) is July (87.8°F).
The month with the lowest average high temperature is December (36.5°F).
- Average low temperature in September: 55.6°F
The month with the highest average low temperature is August (62.2°F).
The coldest month (with the lowest average low temperature) is December (26.2°F).
Average pressure in September
Grandview, WA
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is August (29.92"Hg).
Average wind speed in September
Grandview, WA
- Average wind speed in September: 6.8mph
The windiest month (with the highest average wind speed) is April (8.5mph).
The calmest month (with the lowest average wind speed) is December (5.2mph).
Average humidity in September
Grandview, WA
- Average humidity in September: 45%
The month with the highest relative humidity is January (82%).
The month with the lowest relative humidity is July (37%).
Average rainfall in September
Grandview, WA
- Average rainfall in September: 0.28"
The wettest month (with the highest rainfall) is May (0.71").
The driest month (with the least rainfall) is July (0.2").
Average rainfall days in September
Grandview, WA
- Average rainfall days in September: 5 days
The month with the highest number of rainy days is May (9.2 days).
The month with the least rainy days is July (4 days).
Average snowfall in September
Grandview, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.34").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Grandview, WA
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is December (3.9 days).
The months with the least snowfall days are April, May, June, July, August and October (0 days).
Average daylight in September /
Average sunshine in September
Grandview, WA
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in September: 10h and 5min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is January (Average sunshine: 4h and 54min).
Average sunshine days in September
Grandview, WA
- Average sunshine days in September: 23.1 days
The month with the most sunshine days is July (25.7 days).
The month with the least sunshine days is February (18.7 days).
Average UV index in September
Grandview, WA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Grandview, WA
- Average cloud cover in September: 17
The month with the most cloud cover is January (Cloud cover 49).
The months with the least cloud cover are July and August (Cloud cover 10).
Average visibility in September
Grandview, WA
- Average visibility in September: 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).
Grandview, Washington, USA
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