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
September's arrival coincides with a soft drop in the average high-temperature, subtly decreasing from August's 84.7°F (29.3°C) to a still warm 78.1°F (25.6°C). Isom records a significant temperature drop in September nights, lowering to an average of 56.3°F (13.5°C).Humidity
In September, the average relative humidity in Isom is 77%.Rainfall
September is the month with the least rainfall. Rain falls for 13.5 days and accumulates 1.85" (47mm) of precipitation.Snowfall
In Isom, snow does not fall in June through September.Daylight
The average length of the day in September in Isom, West Virginia, is 12h and 25min.On the first day of the month, sunrise is at 6:58 am and sunset at 7:56 pm. On the last day of September, sunrise is at 7:22 am and sunset at 7:11 pm EDT.
Sunshine
In September, the average sunshine is 8.1h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for average individuals.Note: A maximum daily UV index of 4 during September morphs into the following directions:
Preventative actions are necessary - Recommendations to ward off sunburn are given. When the Sun is at its strongest around midday, find shade and limit exposure. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are September temperatures in Isom?
What is the average humidity in September in Isom?
What is the driest month in Isom?
How many days does it rain in September in Isom?
When it does not snow in Isom?
Does it snow in Isom in September?
How many hours of daylight does Isom have in September?
When are sunrise and sunset in September in Isom?
How many hours of sunshine does Isom have in September?
What is the UV index reading in September in Isom?
Average temperature in September
Isom, WV
- Average high temperature in September: 78.1°F
The warmest month (with the highest average high temperature) is July (85.8°F).
The month with the lowest average high temperature is January (39.7°F).
- Average low temperature in September: 56.3°F
The month with the highest average low temperature is July (62.4°F).
The coldest month (with the lowest average low temperature) is January (26.1°F).
Average pressure in September
Isom, WV
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.98"Hg).
Average wind speed in September
Isom, WV
- Average wind speed in September: 4.2mph
The windiest months (with the highest average wind speed) are January, February and April (6.5mph).
The calmest month (with the lowest average wind speed) is August (4mph).
Average humidity in September
Isom, WV
- Average humidity in September: 77%
The month with the highest relative humidity is February (82%).
The months with the lowest relative humidity are April, June, July, August and November (76%).
Average rainfall in September
Isom, WV
- Average rainfall in September: 1.85"
The wettest month (with the highest rainfall) is May (3.74").
The driest month (with the least rainfall) is September (1.85").
Average rainfall days in September
Isom, WV
- Average rainfall days in September: 13.5 days
The month with the highest number of rainy days is May (20.2 days).
The month with the least rainy days is November (10.8 days).
Average snowfall in September
Isom, WV
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.53").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Isom, WV
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (11.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Isom, WV
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 8h and 1min
The month with the most sunshine is August (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Isom, WV
- Average sunshine days in September: 13.6 days
The months with the most sunshine days are October and November (17 days).
The month with the least sunshine days is February (8.8 days).
Average UV index in September
Isom, WV
- Average UV index in September: 4
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in September
Isom, WV
- Average cloud cover in September: 37
The month with the most cloud cover is January (Cloud cover 62).
The month with the least cloud cover is August (Cloud cover 33).
Average visibility in September
Isom, WV
- Average visibility in September: 5mi
The months with the highest visibility are April and November (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October and December (5mi).
Isom, West Virginia, USA
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