August weather forecast
Key West, FL

August can be deemed as the most active month in terms of weather events in Key West. The intensity of sunlight during day time is counteracted by the occasional thunderstorms which bring respite from the heat. The constant weather changes can sometimes result in unfavorable conditions, but the tropical charm of the city remains intact. Along with the peak of hurricane season, the month offers the highest sea temperatures, peaking at 86.9°F (30.5°C), defining August's marine appeal.

Temperature

The warmest period is August, when temperatures fluctuate between an average high of 85.3°F (29.6°C) and a low of 82.9°F (28.3°C).

Heat index

During August, the heat index is appraised at a very hot 95°F (35°C). Implement additional cautionary measures, heat cramps and heat exhaustion could occur. Prolonged activity might induce heatstroke.
Always consider that heat index estimations are for light winds and places in the shade. Direct sunlight might lead to a heat index increase by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', is the outcome of merging air's temperature and its humidity metrics. Elements such as metabolic variations, pregnancy, and physical exertion can influence one's weather perception. Consider that direct sun exposure can intensify the felt heat, adding potentially 15 Fahrenheit (8 Celsius) degrees to the heat index. Heat index values are highly critical to babies and toddlers. Young kids are often more at risk than adults as they tend to perspire less. Besides, their skin surface is larger relative to their small bodies, and their increased heat output from their active lifestyle compounds their risk.
By perspiring, the human body can shed its excessive warmth since evaporated sweat cools it off. When there is abundant moisture in the air, the body's cooling through the evaporation process becomes less effective, leading to the sensation of overheating. Elevated heat gain compared to the body's release capability poses risks of dehydration and potential overheating.

Humidity

The months with the lowest humidity are July through September, with an average relative humidity of 74%.

Rainfall

In Key West, Florida, during August, the rain falls for 23.1 days and regularly aggregates up to 4.33" (110mm) of precipitation. Throughout the year, in Key West, there are 199.2 rainfall days, and 31.61" (803mm) of precipitation is accumulated.

Ocean temperature

With an average ocean temperature of 86.9°F (30.5°C), August is the month with the warmest seawater.
Note: Many swimmers might find water temperatures beyond 86°F (30°C) to be less than ideal for a refreshing experience.

Daylight

In August, the average length of the day in Key West is 12h and 58min.
On the first day of August, sunrise is at 6:55 am and sunset at 8:11 pm. On the last day of the month, sunrise is at 7:08 am and sunset at 7:46 pm EDT.

Sunshine

The average sunshine in August in Key West is 9.7h.

UV index

April through October, 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 health hazard from unsafe exposure to UV radiation for ordinary individuals.
Note: In August, the maximum UV index of 7 suggests this advice:
Stay clear of intense sun exposure. Solar protection is of utmost significance. Stay in the shade and limit direct Sun exposure from 10 a.m. to 4 p.m., a time when UV radiation is particularly strong. Remember, however, that shade structures may not provide complete protection. Shield yourself from the harmful effects of UV radiation with sun-protective attire, a hat, and quality sunglasses. Attention! UV radiation is ramped up when reflecting off sand and water surfaces.