September weather forecastBrewster, FL
September
Weather in September
The first month of the autumn, September, is also a hot month in Brewster, Florida, with temperature in the range of an average low of 73.6°F (23.1°C) and an average high of 88°F (31.1°C).Temperature
With September's arrival, Brewster notes an average high-temperature of a still hot 88°F (31.1°C), closely following the trend of the preceding month. Throughout the nights in September, Brewster experiences an average low-temperature of 73.6°F (23.1°C).Heat index
The average heat index in September is computed to be a scorching 105.8°F (41°C). Preventive measures are required to mitigate the risk of heat cramps and heat exhaustion. Continuous activity may precipitate heatstroke.Understand that the heat index values take into account shaded locations and mild winds. The heat index could experience an increase of 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is an indicator that blends the effects of temperature and humidity to depict perceived warmth. Factors encompassing physical activity, clothing, and metabolic differences have a role in shaping the individual's impression of temperature. 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 importance for children. Children typically face more danger than adults as their sweat production is usually lower. Additionally, the bigger skin surface compared to their small size and the increased heat due to their activeness exacerbate the risk.
To offset high temperatures, the human body releases sweat which, upon evaporation, cools it down. Increased relative humidity interferes with body cooling by slowing the rate of evaporation, resulting in a slower body cooling rate and a heightened feeling of heat. Overheating dangers loom when the body's heat release mechanisms are overshadowed by excessive gain.
Humidity
The most humid month is September, with an average relative humidity of 80%.Rainfall
In September, the rain falls for 23.5 days. Throughout September, 4.09" (104mm) of precipitation is accumulated. In Brewster, during the entire year, the rain falls for 195.2 days and collects up to 35.47" (901mm) of precipitation.Daylight
The average length of the day in September is 12h and 19min.On the first day of September, sunrise is at 7:07 am and sunset at 7:48 pm. On the last day of the month, sunrise is at 7:20 am and sunset at 7:14 pm EDT.
Sunshine
The average sunshine in September is 8.8h.UV index
The months with the highest UV index in Brewster are May through September, with an average maximum UV index of 7. A UV Index of 6 to 7 symbolizes a high threat to health from exposure to the Sun's UV radiation for the ordinary person.Note: In September, a daily maximum UV index of 7 leads to the following instructions:
Use measures and accept sun safety conventions. Guarding against skin and eye trauma is of high priority. Stay in the shade and avoid direct Sun exposure from 10 a.m. to 4 p.m., a time when UV radiation is at its strongest, and remember that parasols or canopies do not offer full protection. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Brewster, FL
- Average high temperature in September: 88°F
The warmest month (with the highest average high temperature) is August (89.8°F).
The month with the lowest average high temperature is January (70.2°F).
- Average low temperature in September: 73.6°F
The month with the highest average low temperature is August (75.7°F).
The coldest month (with the lowest average low temperature) is January (52.2°F).
Average pressure in September
Brewster, FL
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is September (29.96"Hg).
Average wind speed in September
Brewster, FL
- Average wind speed in September: 5.2mph
The windiest months (with the highest average wind speed) are January and March (7mph).
The calmest month (with the lowest average wind speed) is July (4.7mph).
Average humidity in September
Brewster, FL
- Average humidity in September: 80%
The month with the highest relative humidity is September (80%).
The month with the lowest relative humidity is March (71%).
Average rainfall in September
Brewster, FL
- Average rainfall in September: 4.09"
The wettest month (with the highest rainfall) is August (5.98").
The driest month (with the least rainfall) is February (1.1").
Average rainfall days in September
Brewster, FL
- Average rainfall days in September: 23.5 days
The month with the highest number of rainy days is July (26.6 days).
The month with the least rainy days is January (9.2 days).
Average daylight in September /
Average sunshine in September
Brewster, FL
- Average daylight in September: 12h and 18min
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 September: 8h and 48min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 6h and 18min).
Average sunshine days in September
Brewster, FL
- Average sunshine days in September: 4.5 days
The month with the most sunshine days is January (19.7 days).
The month with the least sunshine days is July (3.1 days).
Average UV index in September
Brewster, 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 month with the lowest UV index is January (UV index 4).
Average cloud cover in September
Brewster, FL
- Average cloud cover in September: 33
The months with the most cloud cover are February and December (Cloud cover 34).
The month with the least cloud cover is May (Cloud cover 28).
Average visibility in September
Brewster, FL
- Average visibility in September: 5mi
The months with the highest visibility are January, February, March, April, May, June, July, August, October, November and December (6mi).
The month with the lowest visibility is September (5mi).





