September weather forecast and climate
Deerfield Beach, FL

The calm sea and white sand of the famous Deerfield Beach in Florida
The calm sea and white sand of the famous Deerfield Beach in Florida
The first month of the autumn, September, is still a warm month in Deerfield Beach, Florida, with average temperature varying between 80.2°F (26.8°C) and 85.3°F (29.6°C).

Temperature

In Deerfield Beach, the average high-temperature in September is essentially the same as in August - a moderately hot 85.3°F (29.6°C). In September, in Deerfield Beach, the average low-temperature is 80.2°F (26.8°C).

Heat index

In September, the average heat index is estimated at a hot 95°F (35°C). Take special precautions - heat exhaustion and heat cramps are expected. Heatstroke may occur with lengthy activity.
Take into consideration that the heat index values are calculated for shade and light wind conditions. With the exposure to direct sunlight, the heat index may be increased by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature', 'feels like', 'real feel', or 'apparent temperature', is a calculated temperature value of how hot it feels when the moisture in the air is factored in. Additional factors like activity, differences in body mass, height, and shape, wind, and metabolic differences affect individual temperature impact. Bear in mind that direct sunshine exposure increases weather impact, and may raise heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. Children are often less aware of the need to rest and re-hydrate. Thirst is a late sign of dehydration - it is vital to remain hydrated, particularly during prolonged physical activities.

Humidity

The average relative humidity in September is 74%.

Rainfall

In September, in Deerfield Beach, Florida, the rain falls for 26.9 days. Throughout September, 7.28" (185mm) of precipitation is accumulated. Throughout the year, there are 243.5 rainfall days, and 53.31" (1354mm) of precipitation is accumulated.

Ocean temperature

In Deerfield Beach, the average water temperature is 85.1°F (29.5°C).
Note: Water temperature between 77°F (25°C) and 84.2°F (29°C) is regarded as very warm and enjoyable by all. With these temperatures, water activities are pleasurable, without feeling uncomfortable for prolonged periods.

Daylight

In September, the average length of the day in Deerfield Beach is 12.3h.

Sunshine

The average sunshine is 8.9h.

UV index

Months with the highest UV index are May through September, with an average maximum UV index of 7. A UV Index of 6 to 7 symbolizes a high health risk from unprotected exposure to the Sun's UV rays for the ordinary person.
Note: In September, the average maximum UV index of 7 translate into the following recommendations:
Take precautions and adopt sun safety practices. Protection against sunburn is obliged. 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. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Beware! The strength of the UV rays is significantly increased by the reflection of the water and sand.

What is the temperature in September in Deerfield Beach?

The average high-temperature, in September, is 85.3°F (29.6°C), while the average low-temperature is 80.2°F (26.8°C). The average heat index (a.k.a. 'apparent temperature', 'real feel'), that factores the actual air temperature with the relative humidity, in September is evaluated at 95°F (35°C).

What is the average humidity in September in Deerfield Beach?

In September, the average relative humidity in Deerfield Beach, Florida, is 74%.

How many days does it rain in September in Deerfield Beach?

In Deerfield Beach, in September, it is raining for 26.9 days, with typically 7.28" (185mm) of accumulated precipitation.

What is the water temperature in September in Deerfield Beach?

In September, the average ocean temperature is 85.1°F (29.5°C). For any water activity, surface water temperatures between 77°F (25°C) and 84.2°F (29°C) are considered as excellent and extremely pleasant for lengthened periods.

What is the average length of the day in September in Deerfield Beach?

The average length of the day in September is 12.3h.

How long on average sun shines in September in Deerfield Beach?

In Deerfield Beach, Florida, the average sunshine in September is 8.9h.

What are the months with the highest UV index in Deerfield Beach?

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

How high is the UV index in September in Deerfield Beach?

In September, the average daily maximum UV index is 7. A UV Index reading of 6 to 7 represents a high health threat from the exposure to the Sun's UV rays.
Average temperature in September - Deerfield Beach, FL
  • Average high temperature in September: 85.3°F

The warmest month (with the highest average high temperature) is August (87.1°F).
The month with the lowest average high temperature is January (72.5°F).

  • Average low temperature in September: 80.2°F

The month with the highest average low temperature is August (81.5°F).
The coldest month (with the lowest average low temperature) is January (64.2°F).

Average pressure in September - Deerfield Beach, FL
  • Average pressure in September: 29.95"

The month with the highest atmospheric pressure is January (30.11").
The month with the lowest atmospheric pressure is September (29.95").

Average wind speed in September - Deerfield Beach, FL
  • Average wind speed in September: 8.4mph

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

Average humidity in September - Deerfield Beach, FL
  • Average humidity in September: 74%

Months with the highest relative humidity are June and December (75%).
The month with the lowest relative humidity is March (70%).

Average rainfall in September - Deerfield Beach, FL
  • Average rainfall in September: 7.28"

The wettest month (with the highest rainfall) is August (8.35").
The driest month (with the least rainfall) is January (1.38").

Average rainfall days in September - Deerfield Beach, FL
  • Average rainfall days in September: 26.9 days

The month with the highest number of rainy days is August (28 days).
The month with the least rainy days is February (13 days).

Average sea temperature in September - Deerfield Beach, FL
  • Average sea temperature in September: 85.1°F

The best month for swimming (with the highest average sea temperature) is August (86.3°F).
The coldest months (with the lowest average sea temperature) are January and February (74.2°F).

Average daylight in September / Average sunshine in September - Deerfield Beach, FL
  • Average daylight in September: 12.3h

The month with the longest days is June (Average daylight: 13.8h).
The month with the shortest days is December (Average daylight: 10.5h).

  • Average sunshine in September: 8.9h

The month with the most sunshine is July (Average sunshine: 10.9h).
Months with the least sunshine are January and December (Average sunshine: 6.2).

Average sunshine days in September - Deerfield Beach, FL
  • Average sunshine days in September: 2.3 days

The month with the most sunshine days is March (12.1 days).
Months with the least sunshine days are July and August (1.7 days).

Average UV index in September - Deerfield Beach, FL
  • Average UV index in September: 7

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 5).

Average cloud cover in September - Deerfield Beach, FL
  • Average cloud cover in September: 31

The month with the most cloud cover is October (Cloud cover 36).
Months with the least cloud cover are April and July (Cloud cover 28).

Average visibility in September - Deerfield Beach, FL
  • Average visibility in September: 6mi

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