September weather forecast
Jupiter Island, FL

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Weather in September

The first month of the autumn, September, is also a moderately hot month in Jupiter Island, Florida, with temperature in the range of an average low of 79.2°F (26.2°C) and an average high of 84.7°F (29.3°C).

Temperature

Welcoming September, Jupiter Island notes an average high-temperature of a warm 84.7°F (29.3°C), nearly consistent with August's 86.5°F (30.3°C). Jupiter Island, during September nights, witnesses an average temperature marginally cooler than its daytime highs, at a still moderately hot 79.2°F (26.2°C).

Heat index

For most parts of September, the heat index is calculated to be a very hot 95°F (35°C). More safety actions are required, heat exhaustion and heat cramps are probable. Long-term activity may precipitate heatstroke.
Note that heat index values are valued for light wind and location in the shade. When under direct sunshine, the heat index may be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is the outcome of merging air's temperature and its humidity metrics. The impact of temperature is individual, as people's perception of weather may change based on their body mass, height, and physical activity. In direct sunlight, the heat's impact can be heightened, potentially leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to babies and toddlers. Children regularly disregard the necessity to rest and replenish fluids. Thirst is a late symptom of dehydration - thus, maintaining hydration, particularly during long-lasting physical activities, is essential.
To offset high temperatures, the human body releases sweat which, upon evaporation, cools it down. When relative humidity increases, the body's capacity to evaporate heat decreases, leading to a heightened sense of warmth. When the body is unable to balance heat gain, its temperature elevates, which may induce thermal illnesses.

Humidity

The average relative humidity in September in Jupiter Island, Florida, is 76%.

Rainfall

In Jupiter Island, during September, the rain falls for 24.7 days and regularly aggregates up to 5.35" (136mm) of precipitation. Throughout the year, there are 227.4 rainfall days, and 44.72" (1136mm) of precipitation is accumulated.

Daylight

In Jupiter Island, Florida, the average length of the day in September is 12h and 19min.
On the first day of the month, sunrise is at 7:00 am and sunset at 7:40 pm. On the last day of September, in Jupiter Island, sunrise is at 7:12 am and sunset at 7:07 pm EDT.

Sunshine

The average sunshine in September in Jupiter Island, Florida, is 8.9h.

UV index

May through September, with an average maximum UV index of 7, are months with the highest UV index. A UV Index value of 6 to 7 symbolizes a high threat to health from exposure to the Sun's UV radiation for ordinary individuals.
Note: An average maximum UV index of 7 in September leads to these recommendations:
Resist extreme sun exposure. Guarding against solar damage is essential. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.
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Frequently asked questions

Is it hot in Jupiter Island during September?

The high-temperature, in September, in Jupiter Island, records 84.7°F (29.3°C), while the low-temperature is 79.2°F (26.2°C). In September, the average heat index (a.k.a. 'real feel', 'apparent temperature'), which takes the relative humidity and factors it into the air temperature reading, is calculated to be 95°F (35°C).

What is the average humidity in September in Jupiter Island?

In September, the average relative humidity in Jupiter Island is 76%.

How many days does it rain in September in Jupiter Island?

In Jupiter Island, Florida, in September, it is raining for 24.7 days, with typically 5.35" (136mm) of accumulated precipitation.

How many hours of daylight does Jupiter Island have in September?

In Jupiter Island, the average day length in September is 12h and 19min.

When is the sunrise / sunset in September in Jupiter Island?

In September, on the first day of the month, sunrise is at 7:00 am and sunset at 7:40 pm. On the last day of the month, sunrise is at 7:12 am and sunset at 7:07 pm EDT.

How long on average sun shines in September in Jupiter Island?

In Jupiter Island, the average sunshine duration in September is 8.9h.

What are the months with the highest UV index in Jupiter Island?

The months with the highest UV index are May through September, with an average maximum UV index of 7.

What is the UV index reading in September in Jupiter Island?

In Jupiter Island, Florida, the average daily maximum UV index in September is 7. A UV Index reading of 6 to 7 represents a high health threat from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Jupiter Island, FL

Average temperature in September - Jupiter Island, FL
  • Average high temperature in September: 84.7°F

The warmest month (with the highest average high temperature) is August (86.5°F).
The month with the lowest average high temperature is January (71.2°F).

  • Average low temperature in September: 79.2°F

The month with the highest average low temperature is August (81°F).
The coldest month (with the lowest average low temperature) is January (63.1°F).

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Average pressure in September
Jupiter Island, FL

Average pressure in September - Jupiter Island, FL
  • Average pressure in September: 29.96"Hg

The month with the highest atmospheric pressure is January (30.12"Hg).
The months with the lowest atmospheric pressure are September and October (29.96"Hg).

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Average wind speed in September
Jupiter Island, FL

Average wind speed in September - Jupiter Island, FL
  • Average wind speed in September: 8.6mph

The windiest month (with the highest average wind speed) is January (11.4mph).
The calmest month (with the lowest average wind speed) is July (7.8mph).

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Average humidity in September
Jupiter Island, FL

Average humidity in September - Jupiter Island, FL
  • Average humidity in September: 76%

The month with the highest relative humidity is June (78%).
The month with the lowest relative humidity is March (71%).

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Average rainfall in September
Jupiter Island, FL

Average rainfall in September - Jupiter Island, FL
  • Average rainfall in September: 5.35"

The wettest month (with the highest rainfall) is August (7.64").
The driest month (with the least rainfall) is January (1.34").

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Average rainfall days in September
Jupiter Island, FL

Average rainfall days in September - Jupiter Island, FL
  • Average rainfall days in September: 24.7 days

The month with the highest number of rainy days is August (26.7 days).
The month with the least rainy days is January (13 days).

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Average daylight in September /
Average sunshine in September
Jupiter Island, FL

Average daylight in September / Average sunshine in September - Jupiter Island, FL
  • Average daylight in September: 12h and 2min

The month with the longest days is June (Average daylight: 13h and 48min).
The month with the shortest days is December (Average daylight: 10h and 30min).

  • Average sunshine in September: 8h and 5min

The months with the most sunshine are July and August (Average sunshine: 10h and 48min).
The month with the least sunshine is January (Average sunshine: 5h and 54min).

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Average sunshine days in September
Jupiter Island, FL

Average sunshine days in September - Jupiter Island, FL
  • Average sunshine days in September: 3.8 days

The month with the most sunshine days is January (14.3 days).
The month with the least sunshine days is August (2.4 days).

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Average UV index in September
Jupiter Island, FL

Average UV index in September - Jupiter Island, FL
  • Average UV index in September: 7

The months with the highest UV index are May, June, July, August and September (UV index 7).
The months with the lowest UV index are January and February (UV index 5).

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Average cloud cover in September
Jupiter Island, FL

Average cloud cover in September - Jupiter Island, FL
  • Average cloud cover in September: 31

The months with the most cloud cover are November and December (Cloud cover 37).
The month with the least cloud cover is July (Cloud cover 28).

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Average visibility in September
Jupiter Island, FL

Average visibility in September - Jupiter Island, FL
  • Average visibility in September: 6mi

The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).

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Jupiter Island, Florida, USA

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