August weather forecast
Port Saint John, FL

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Weather in August

August, the last month of the summer in Port Saint John, is another hot month, with temperature in the range of an average high of 88.7°F (31.5°C) and an average low of 77.9°F (25.5°C).

Temperature

August, on average, is the warmest month, registering a high temperature of 88.7°F (31.5°C) and a low of 77.9°F (25.5°C).

Heat index

The heat index for August is estimated at a blistering 107.6°F (42°C). Implement heightened safety measures - risk of heat exhaustion and heat cramps is increased. Prolonged activity may result in heatstroke.
Note that heat index values are valued for light wind and location in the shade. Heat index values may rise by up to 15 Fahrenheit (8 Celsius) degrees when exposed to direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', combines both the air temperature and the humidity level to give a perceived human temperature. The impact of weather on an individual can be subjective, affected by the person's activity and heat perception, which can vary due to elements including wind, clothing, and metabolic differences. It is noteworthy to mention that direct sunlight exposure can augment the felt temperature, leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular significance for children. Younglings are generally more in peril than adults due to their reduced perspiration. Coupled with a larger skin surface relative to their tiny bodies and greater heat production because of their activity, they become more at risk.
To cool down, the human body relies on perspiration, a process where excessive heat is eliminated as sweat evaporates. An increase in relative humidity disrupts body cooling by slowing the evaporation rate, thereby reducing the rate at which the body cools and amplifying the sense of heat. Overheating and potential dehydration arise when body heat gain eclipses its release capability.

Humidity

The most humid month is August, with an average relative humidity of 79%.

Rainfall

August is the month with the most rainfall. Rain falls for 25.8 days and accumulates 6.81" (173mm) of precipitation.

Daylight

In Port Saint John, the average length of the day in August is 13h and 8min.
On the first day of August, sunrise is at 6:45 am and sunset at 8:13 pm. On the last day of the month, sunrise is at 7:01 am and sunset at 7:45 pm EDT.

Sunshine

The average sunshine in August in Port Saint John is 10.6h.

UV index

The months with the highest UV index are May through September, with an average maximum UV index of 7. A UV Index estimate of 6 to 7 represents a high health hazard from exposure to the Sun's UV rays for the ordinary person.
Note: The UV index of 7 during August translates into the following guidance:
Enforce precautions and stick to sun safety measures. Preservation from skin and eye damage is essential. Make an effort to avoid direct sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation, and note that objects like parasols or canopies might not offer full sun protection. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days.
Updated: Jul 16, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are the warmest months?

The warmest month is August, with an average high-temperature of 88.7°F (31.5°C) and an average low-temperature of 77.9°F (25.5°C).

Is it hot during August?

During August, Port Saint John experiences an average high-temperature of 88.7°F (31.5°C) and a low-temperature of 77.9°F (25.5°C). In August, the average heat index (a.k.a. 'apparent temperature', 'feels like'), which calculates the temperature value influenced by the moisture in the air, is estimated at 107.6°F (42°C).

What is the most humid month?

The most humid month in Port Saint John is August, with an average relative humidity of 79%.

What is the average humidity in August in Port Saint John?

In Port Saint John, the average relative humidity in August is 79%.

What is the wettest month?

The month with the most rainfall is August, when the rain falls for 25.8 days and typically aggregates up to 6.81" (173mm) of precipitation.

How many days does it rain in August?

In August, the rain falls for 25.8 days. Throughout August, 6.81" (173mm) of precipitation is accumulated.

What is the average length of the day in August?

In Port Saint John, the average day length in August is 13h and 8min.

When are sunrise and sunset in August?

In August, on the first day of the month, sunrise is at 6:45 am and sunset at 8:13 pm. On the last day of the month, sunrise is at 7:01 am and sunset at 7:45 pm EDT.

How long on average sun shines in August?

The average sunshine duration in August is 10.6h.

What is the month with the highest UV index in Port Saint John?

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

What is the UV index reading in August?

In August, the average daily maximum UV index is 7. A UV Index of 6 to 7 symbolizes a high hazard to health from exposure to the Sun's 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 August
Port Saint John, FL

Average temperature in August - Port Saint John, FL
  • Average high temperature in August: 88.7°F

The warmest month (with the highest average high temperature) is August (88.7°F).
The month with the lowest average high temperature is January (68.4°F).

  • Average low temperature in August: 77.9°F

The month with the highest average low temperature is August (77.9°F).
The coldest month (with the lowest average low temperature) is January (56.1°F).

Average pressure in August
Port Saint John, FL

Average pressure in August - Port Saint John, FL
  • Average pressure in August: 29.99"Hg

The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is September (29.97"Hg).

Average wind speed in August
Port Saint John, FL

Average wind speed in August - Port Saint John, FL
  • Average wind speed in August: 6.3mph

The windiest months (with the highest average wind speed) are January and November (8.8mph).
The calmest month (with the lowest average wind speed) is July (6mph).

Average humidity in August
Port Saint John, FL

Average humidity in August - Port Saint John, FL
  • Average humidity in August: 79%

The month with the highest relative humidity is August (79%).
The month with the lowest relative humidity is March (71%).

Average rainfall in August
Port Saint John, FL

Average rainfall in August - Port Saint John, FL
  • Average rainfall in August: 6.81"

The wettest month (with the highest rainfall) is August (6.81").
The driest month (with the least rainfall) is March (1.42").

Average rainfall days in August
Port Saint John, FL

Average rainfall days in August - Port Saint John, FL
  • Average rainfall days in August: 25.8 days

The months with the highest number of rainy days are July and August (25.8 days).
The month with the least rainy days is February (10.8 days).

Average daylight in August /
Average sunshine in August
Port Saint John, FL

Average daylight in August / Average sunshine in August - Port Saint John, FL
  • Average daylight in August: 13h and 1min

The month with the longest days is June (Average daylight: 13h and 54min).
The month with the shortest days is December (Average daylight: 10h and 24min).

  • Average sunshine in August: 10h and 4min

The month with the most sunshine is July (Average sunshine: 11h and 0min).
The months with the least sunshine are January, November and December (Average sunshine: 6h and 6min).

Average sunshine days in August
Port Saint John, FL

Average sunshine days in August - Port Saint John, FL
  • Average sunshine days in August: 2.3 days

The months with the most sunshine days are January and March (17.2 days).
The month with the least sunshine days is August (2.3 days).

Average UV index in August
Port Saint John, FL

Average UV index in August - Port Saint John, FL
  • Average UV index in August: 7

The months with the highest UV index are May, June, July, August and September (UV index 7).
The month with the lowest UV index is January (UV index 4).

Average cloud cover in August
Port Saint John, FL

Average cloud cover in August - Port Saint John, FL
  • Average cloud cover in August: 28

The months with the most cloud cover are January, November and December (Cloud cover 35).
The month with the least cloud cover is May (Cloud cover 26).

Average visibility in August
Port Saint John, FL

Average visibility in August - Port Saint John, FL
  • Average visibility in August: 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).

Port Saint John, Florida, USA

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