May weather forecastSt. Augustine, FL

Weather in May

May gains prominence in St. Augustine as a prelude to the city's famous summer weather. The city starts transitioning from temperate to a tropical climate, with an observable increase in temperature and humidity. Interestingly, the average rainfall measures approximately 3.1" (79mm) throughout this month. The combination of extended daylight hours with plentiful sunshine ensures vibrant colors dominating the landscape. May's scintillating weather validates the adage "April showers bring May flowers," marking the advent of the summer season.

Temperature

St. Augustine observes a slight uplift in the average high-temperature with the onset of May, adjusting from April's moderately hot 78.1°F (25.6°C) to a still warm 84°F (28.9°C). An average low-temperature of 64.9°F (18.3°C) is observed during May nights in St. Augustine.

Rainfall

In St. Augustine, in May, during 8 rainfall days, 3.11" (79mm) of precipitation is typically accumulated. In St. Augustine, during the entire year, the rain falls for 116 days and collects up to 50" (1270mm) of precipitation.

Ocean temperature

In May, the average ocean temperature in St. Augustine is 75.7°F (24.3°C).
Note: A person's cold intolerance, with sunshine, wind, and air temperature, are essential factors for enjoying swimming in 75.7°F (24.3°C) water. (FYI: The Olympic swimming competition requires a water temperature between 77°F (25°C) and 82.4°F (28°C).)

Daylight

In May, the average length of the day in St. Augustine is 13h and 40min.
On the first day of May in St. Augustine, sunrise is at 6:41 am and sunset at 8:02 pm. On the last day of the month, sunrise is at 6:24 am and sunset at 8:21 pm EDT.

Sunshine

The months with the most sunshine in St. Augustine are March through August, with an average of 9h of sunshine.

UV index

In St. Augustine, the average daily maximum UV index in May is 10. A UV Index estimate of 8 to 10 represents a very high threat to health from exposure to the Sun's UV rays for the average person.
Note: In May, a daily UV index of 10 turns into the following recommendations:
Take extra precautions. Protection against sun damage is required. The Sun's UV radiation is most intense from 10 a.m. to 4 p.m. Try to avoid direct sun exposure 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. Ensure the liberal application and reapplication of a broad-spectrum SPF 30+ sunscreen after each outdoor activity or swim, and every two hours. Take warning! Reflective sand and water surfaces intensify the Sun's UV rays.