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
The shift from August to September includes a small decrease in the average high-temperature, from a warm 78.4°F (25.8°C) to an agreeable 72°F (22.2°C). Saint Johns sees an average low-temperature of 52°F (11.1°C) during September.Humidity
The average relative humidity in September is 80%.Rainfall
The month with the least rainfall is September, when the rain falls for 8.9 days and typically collects 0.55" (14mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In Saint Johns, the average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:31 am and sunset at 7:36 pm. On the last day of September, sunrise is at 7:00 am and sunset at 6:47 pm EDT.
Sunshine
In September, the average sunshine is 8.3h.UV index
In Saint Johns, Pennsylvania, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV rays for the ordinary person.Note: The UV index of 4 during September leads to these advisories:
Take heed. Individuals of lighter complexion can be burned in less than half an hour. Avoiding the Sun during its peak radiation time around midday is a healthy practice. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in September?
What is the average humidity in September in Saint Johns?
What is the driest month in Saint Johns?
How many days does it rain in September?
When it does not snow?
Does it snow in September?
What is the average length of the day in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
Saint Johns, PA
- Average high temperature in September: 72°F
The warmest month (with the highest average high temperature) is July (81°F).
The month with the lowest average high temperature is January (31.5°F).
- Average low temperature in September: 52°F
The month with the highest average low temperature is July (59.5°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure in September
Saint Johns, PA
- Average pressure in September: 30.07"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Saint Johns, PA
- Average wind speed in September: 5.7mph
The windiest month (with the highest average wind speed) is March (8.5mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity in September
Saint Johns, PA
- Average humidity in September: 80%
The month with the highest relative humidity is February (84%).
The month with the lowest relative humidity is April (78%).
Average rainfall in September
Saint Johns, PA
- Average rainfall in September: 0.55"
The wettest month (with the highest rainfall) is May (1.26").
The driest month (with the least rainfall) is September (0.55").
Average rainfall days in September
Saint Johns, PA
- Average rainfall days in September: 8.9 days
The month with the highest number of rainy days is May (13.8 days).
The month with the least rainy days is January (5.4 days).
Average snowfall in September
Saint Johns, PA
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.81").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Saint Johns, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Saint Johns, PA
- Average daylight in September: 12h and 3min
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 September: 8h and 2min
The month with the most sunshine is July (Average sunshine: 9h and 54min).
The month with the least sunshine is February (Average sunshine: 3h and 36min).
Average sunshine days in September
Saint Johns, PA
- Average sunshine days in September: 18.6 days
The month with the most sunshine days is November (20.6 days).
The month with the least sunshine days is May (14.3 days).
Average UV index in September
Saint Johns, PA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, October, November and December (UV index 2).
Average cloud cover in September
Saint Johns, PA
- Average cloud cover in September: 43
The month with the most cloud cover is February (Cloud cover 61).
The month with the least cloud cover is July (Cloud cover 37).
Average visibility in September
Saint Johns, PA
- Average visibility in September: 5mi
The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (5mi).
Saint Johns, Pennsylvania, USA
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