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
An average high-temperature of a still refreshing 15.2°C (59.4°F) marks September, exhibiting a close resemblance to the conditions in August. A consistent average low of 13.3°C (55.9°F) is noted throughout September, only a small step down from its daytime high.Humidity
In September, the average relative humidity is 81%.Rainfall
In September, in Saint Johns, the rain falls for 14 days. Throughout September, 37mm (1.46") of precipitation is accumulated. In Saint Johns, during the entire year, the rain falls for 185.3 days and collects up to 494mm (19.45") of precipitation.Snowfall
In Saint Johns, snow does not fall in May through October.Daylight
In September, the average length of the day in Saint Johns is 12h and 42min.On the first day of the month, sunrise is at 06:27 and sunset at 20:08. On the last day of September, in Saint Johns, sunrise is at 07:19 and sunset at 18:56 BST.
Sunshine
In September, the average sunshine is 7h.UV index
The months with the highest UV index are May through September, with an average maximum UV index of 4. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for the ordinary person.Note: The maximum UV index of 4 during September translates into these guidelines:
Put precautions into practice - Protective measures against sun-induced damage are advised. The Sun's radiation is especially intense around midday; try to stay in shade during this period. Wearing sunglasses with both UVA and UVB protection effectively reduces sun-induced eye damage.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature in Saint Johns?
What is the average humidity in September in Saint Johns?
How many days does it rain in September in Saint Johns?
When it does not snow in Saint Johns?
How many hours of daylight does Saint Johns have in September?
When are sunrise and sunset in September in Saint Johns?
How long on average sun shines in September in Saint Johns?
What is the month with the highest UV index in Saint Johns?
What is the UV index intensity in September in Saint Johns?
Average temperature in September
Saint Johns, Isle of Man
- Average high temperature in September: 15.2°C
The warmest month (with the highest average high temperature) is August (15.9°C).
The month with the lowest average high temperature is February (7.4°C).
- Average low temperature in September: 13.3°C
The month with the highest average low temperature is August (13.8°C).
The coldest month (with the lowest average low temperature) is February (5.2°C).
Average pressure in September
Saint Johns, Isle of Man
- Average pressure in September: 1014.7mbar
The month with the highest atmospheric pressure is May (1015.9mbar).
The month with the lowest atmospheric pressure is November (1007.9mbar).
Average wind speed in September
Saint Johns, Isle of Man
- Average wind speed in September: 27.2km/h
The windiest month (with the highest average wind speed) is December (34.4km/h).
The calmest month (with the lowest average wind speed) is June (19.7km/h).
Average humidity in September
Saint Johns, Isle of Man
- Average humidity in September: 81%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is November (77%).
Average rainfall in September
Saint Johns, Isle of Man
- Average rainfall in September: 37mm
The wettest month (with the highest rainfall) is November (63mm).
The driest months (with the least rainfall) are April and May (24mm).
Average rainfall days in September
Saint Johns, Isle of Man
- Average rainfall days in September: 14 days
The month with the highest number of rainy days is November (19.6 days).
The month with the least rainy days is February (12.5 days).
Average snowfall in September
Saint Johns, Isle of Man
- Average snowfall in September: 0mm
The month with the highest snowfall is March (16mm).
The months with the least snowfall are May, June, July, August, September and October (0mm).
Average snowfall days in September
Saint Johns, Isle of Man
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (1.3 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Saint Johns, Isle of Man
- Average daylight in September: 12h and 4min
The month with the longest days is June (Average daylight: 17h and 6min).
The month with the shortest days is December (Average daylight: 7h and 30min).
- Average sunshine in September: 7h and 0min
The month with the most sunshine is May (Average sunshine: 8h and 12min).
The months with the least sunshine are January and November (Average sunshine: 3h and 48min).
Average sunshine days in September
Saint Johns, Isle of Man
- Average sunshine days in September: 13.4 days
The month with the most sunshine days is May (16.6 days).
The month with the least sunshine days is November (7.5 days).
Average UV index in September
Saint Johns, Isle of Man
- Average UV index in September: 4
The months with the highest UV index are May, June, July, August and September (UV index 4).
The months with the lowest UV index are January, February and March (UV index 2).
Average cloud cover in September
Saint Johns, Isle of Man
- Average cloud cover in September: 52
The month with the most cloud cover is January (Cloud cover 63).
The month with the least cloud cover is May (Cloud cover 46).
Average visibility in September
Saint Johns, Isle of Man
- Average visibility in September: 10km
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (10km).
The month with the lowest visibility is January (9km).
Saint Johns, Isle of Man
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