September weather forecastRock Harbor, FL
September
Weather in September
September, the first month of the autumn in Rock Harbor, is also a moderately hot month, with an average temperature ranging between max 84.6°F (29.2°C) and min 81.7°F (27.6°C).Temperature
September's onset brings an average high-temperature of a still moderately hot 84.6°F (29.2°C), showing a minute difference from August's 85.5°F (29.7°C). Night temperatures during September experience a slight downturn, averaging a still warm 81.7°F (27.6°C).Heat index
In September, the heat index is computed to be a tropical 93.2°F (34°C). Implement additional preventive actions, heat cramps and heat exhaustion are potential hazards. Heatstroke could follow prolonged activity.Heat index data is primarily for areas with shade and subjected to light winds. If directly exposed to the sun, the heat index could rise by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', measures the perceived warmth when incorporating the humidity present in the air. A person's impression of weather can be affected by numerous aspects, among them metabolic variations, pregnancy, and activity levels. It is essential to be conscious of the fact that direct sunlight can intensify the felt heat, leading to an elevation in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular significance for children. Young ones regularly neglect the requirement for rest and fluid replenishment. Thirst is a late stage of dehydration - so, it is necessary to keep hydrated, particularly during extended periods of physical exertion.
Humidity
The average relative humidity in September is 74%.Rainfall
In Rock Harbor, in September, during 22.9 rainfall days, 4.25" (108mm) of precipitation is typically accumulated. In Rock Harbor, during the entire year, the rain falls for 190.1 days and collects up to 27.05" (687mm) of precipitation.Daylight
The average length of the day in September is 12h and 17min.On the first day of September, sunrise is at 7:02 am and sunset at 7:40 pm. On the last day of the month, sunrise is at 7:13 am and sunset at 7:09 pm EDT.
Sunshine
The average sunshine in September is 9h.UV index
The months with the highest UV index are April through October, with an average maximum UV index of 7. A UV Index of 6 to 7 symbolizes a high threat to health from unsafe exposure to UV radiation for the average person.Note: In September, the average maximum UV index of 7 translates into the following recommendations:
Guard oneself from overexposure. Defence against sun injury is vital. Be aware that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. and try to reduce direct sun exposure during this period as much as possible. Sun-related eye harm can be minimized with proper sunglasses offering UVA and UVB coverage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Rock Harbor, FL
- Average high temperature in September: 84.6°F
The warmest month (with the highest average high temperature) is August (85.5°F).
The month with the lowest average high temperature is January (72.7°F).
- Average low temperature in September: 81.7°F
The month with the highest average low temperature is August (82.9°F).
The coldest month (with the lowest average low temperature) is January (66.9°F).
Average pressure in September
Rock Harbor, FL
- Average pressure in September: 29.94"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The months with the lowest atmospheric pressure are September and October (29.94"Hg).
Average wind speed in September
Rock Harbor, FL
- Average wind speed in September: 9.4mph
The windiest month (with the highest average wind speed) is January (12.9mph).
The calmest month (with the lowest average wind speed) is July (8.9mph).
Average humidity in September
Rock Harbor, FL
- Average humidity in September: 74%
The months with the highest relative humidity are February, June and December (76%).
The month with the lowest relative humidity is March (73%).
Average rainfall in September
Rock Harbor, FL
- Average rainfall in September: 4.25"
The wettest month (with the highest rainfall) is August (4.33").
The driest month (with the least rainfall) is March (0.59").
Average rainfall days in September
Rock Harbor, FL
- Average rainfall days in September: 22.9 days
The month with the highest number of rainy days is September (22.9 days).
The month with the least rainy days is February (9.7 days).
Average daylight in September /
Average sunshine in September
Rock Harbor, FL
- Average daylight in September: 12h and 18min
The month with the longest days is June (Average daylight: 13h and 42min).
The month with the shortest days is December (Average daylight: 10h and 36min).
- Average sunshine in September: 9h and 0min
The month with the most sunshine is July (Average sunshine: 11h and 0min).
The month with the least sunshine is December (Average sunshine: 6h and 24min).
Average sunshine days in September
Rock Harbor, FL
- Average sunshine days in September: 5.2 days
The month with the most sunshine days is January (17.3 days).
The month with the least sunshine days is September (5.2 days).
Average UV index in September
Rock Harbor, FL
- Average UV index in September: 7
The months with the highest UV index are April, May, June, July, August, September and October (UV index 7).
The month with the lowest UV index is January (UV index 5).
Average cloud cover in September
Rock Harbor, FL
- Average cloud cover in September: 30
The month with the most cloud cover is October (Cloud cover 35).
The month with the least cloud cover is April (Cloud cover 26).
Average visibility in September
Rock Harbor, 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).





