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 onset introduces a mild reduction in the average high-temperature, from a moderately hot 75.7°F (24.3°C) in August to an agreeable 69.3°F (20.7°C). An average low-temperature of 49.8°F (9.9°C) is anticipated throughout the nights in McLean during September.Humidity
In September, the average relative humidity in McLean is 82%.Rainfall
In McLean, in September, it is raining for 14.2 days, with typically 2.52" (64mm) of accumulated precipitation. In McLean, New York, during the entire year, the rain falls for 165.9 days and collects up to 34.41" (874mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 29min.On the first day of September in McLean, sunrise is at 6:30 am and sunset at 7:38 pm. On the last day of the month, sunrise is at 7:02 am and sunset at 6:47 pm EDT.
Sunshine
In September, the average sunshine is 8.4h.UV index
The average daily maximum UV index in September in McLean, New York, is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for ordinary individuals.Note: In September, the UV index of 3 transforms into the following advice:
Put precautions into practice - Guidance to elude sunburn is provided. During midday, the Sun's radiation is strongest, and it's advisable to reduce direct exposure. Opt for tightly woven and loose clothing to enhance protection from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for McLean in September?
What is the average humidity in September in McLean?
How much does it rain in McLean in September?
When it does not snow in McLean?
Does it snow in McLean in September?
What is the average length of the day in September in McLean?
When is the sunrise / sunset in September in McLean?
How long on average sun shines in September in McLean?
What is the UV index reading in September in McLean?
Average temperature in September
McLean, NY
- Average high temperature in September: 69.3°F
The warmest month (with the highest average high temperature) is July (78.4°F).
The month with the lowest average high temperature is January (27.3°F).
- Average low temperature in September: 49.8°F
The month with the highest average low temperature is July (57.4°F).
The coldest month (with the lowest average low temperature) is January (16°F).
Average pressure in September
McLean, NY
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
McLean, NY
- Average wind speed in September: 6.5mph
The windiest month (with the highest average wind speed) is January (9.9mph).
The calmest month (with the lowest average wind speed) is August (5.9mph).
Average humidity in September
McLean, NY
- Average humidity in September: 82%
The month with the highest relative humidity is February (88%).
The months with the lowest relative humidity are April, May and July (80%).
Average rainfall in September
McLean, NY
- Average rainfall in September: 2.52"
The wettest month (with the highest rainfall) is June (3.46").
The driest month (with the least rainfall) is January (2.24").
Average rainfall days in September
McLean, NY
- Average rainfall days in September: 14.2 days
The month with the highest number of rainy days is July (18.3 days).
The month with the least rainy days is January (6.7 days).
Average snowfall in September
McLean, NY
- Average snowfall in September: 0"
The month with the highest snowfall is February (9.17").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
McLean, NY
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (20.2 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
McLean, NY
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 8h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is February (Average sunshine: 2h and 24min).
Average sunshine days in September
McLean, NY
- Average sunshine days in September: 13.8 days
The month with the most sunshine days is September (13.8 days).
The month with the least sunshine days is February (5.1 days).
Average UV index in September
McLean, NY
- Average UV index in September: 3
The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January, February and December (UV index 1).
Average cloud cover in September
McLean, NY
- Average cloud cover in September: 41
The month with the most cloud cover is February (Cloud cover 76).
The months with the least cloud cover are July and August (Cloud cover 38).
Average visibility in September
McLean, NY
- Average visibility in September: 5mi
The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (5mi).
The months with the lowest visibility are January and February (4mi).
McLean, New York, USA
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