May weather forecastJohn, French Guiana
May
Weather in May
The last month of the spring, May, is another warm month in John, French Guiana, with an average temperature ranging between min 23.3°C (73.9°F) and max 29.5°C (85.1°F).Temperature
May ushers in an average high-temperature of a still warm 29.5°C (85.1°F), aligning closely with the preceding month. John, during the month of May, experiences an average low-temperature of 23.3°C (73.9°F).Heat index
The heat index in May is evaluated at a torrid 38°C (100.4°F). Heightened precautions are necessary, heat cramps and heat exhaustion are potential risks. Continuous activity could lead to heatstroke.The heat index's values are generally associated with conditions in shade and light breezes. Direct sunlight can cause a surge in the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', evaluates the perceived heat by adding the effect of moisture in the air. The impact of weather on an individual can be subjective, affected by the person's activity and heat perception, which can vary due to elements including wind, clothing, and metabolic differences. Direct exposure to the sun's rays can enhance the felt temperature, increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for babies and toddlers. Young children typically face greater hazards than adults because they do not sweat as much. Their larger skin surface in comparison to their little bodies and the high heat production from their active nature compounds their vulnerability.
The natural cooling mechanism in humans involves perspiration, where the evaporation of sweat balances out excessive warmth. Under high air temperature and humidity (high heat index) conditions, perspiration is limited, and the perception of heat is increased. If the body retains more heat than it can expel, the increasing temperature can lead to heat-related conditions.
Humidity
In John, the average relative humidity in May is 86%.Rainfall
The month with the most rainfall is May, when the rain falls for 28 days and typically aggregates up to 137mm (5.39") of precipitation.Daylight
The average length of the day in May is 12h and 21min.On the first day of May, sunrise is at 06:22 and sunset at 18:40. On the last day of the month, sunrise is at 06:20 and sunset at 18:43 -03.
Sunshine
In John, the average sunshine in May is 5.9h.UV index
The months with the lowest UV index are January through June and December, with an average maximum UV index of 6. A UV Index estimate of 6 to 7 represents a high health vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: The maximum UV index, 6 during May, leads to the following recommendations:
Guard against overexposure. Protection from sun-induced harm is essential. Limit direct sun exposure and seek shade between 10 a.m. and 4 p.m., the time of the most intense UV radiation, noting that shade structures may not provide total sun protection. A hat with a broad brim is indispensable, filtering out up to half of UV rays.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
John, French Guiana
- Average high temperature in May: 29.5°C
The warmest month (with the highest average high temperature) is October (33.1°C).
The month with the lowest average high temperature is February (29.1°C).
- Average low temperature in May: 23.3°C
The month with the highest average low temperature is May (23.3°C).
The coldest month (with the lowest average low temperature) is July (22.2°C).
Average pressure in May
John, French Guiana
- Average pressure in May: 1012.2mbar
The months with the highest atmospheric pressure are June and July (1012.9mbar).
The month with the lowest atmospheric pressure is November (1009.5mbar).
Average wind speed in May
John, French Guiana
- Average wind speed in May: 8.2km/h
The windiest months (with the highest average wind speed) are February and March (9.5km/h).
The calmest month (with the lowest average wind speed) is July (6.4km/h).
Average humidity in May
John, French Guiana
- Average humidity in May: 86%
The month with the highest relative humidity is June (88%).
The month with the lowest relative humidity is October (77%).
Average rainfall in May
John, French Guiana
- Average rainfall in May: 137mm
The wettest month (with the highest rainfall) is May (137mm).
The driest month (with the least rainfall) is October (23mm).
Average rainfall days in May
John, French Guiana
- Average rainfall days in May: 28 days
The month with the highest number of rainy days is May (28 days).
The month with the least rainy days is September (11.5 days).
Average daylight in May /
Average sunshine in May
John, French Guiana
- Average daylight in May: 12h and 18min
The month with the longest days is June (Average daylight: 12h and 24min).
The month with the shortest days is December (Average daylight: 11h and 48min).
- Average sunshine in May: 5h and 54min
The month with the most sunshine is September (Average sunshine: 9h and 6min).
The month with the least sunshine is February (Average sunshine: 5h and 6min).
Average sunshine days in May
John, French Guiana
- Average sunshine days in May: 1.8 days
The month with the most sunshine days is October (16 days).
The month with the least sunshine days is May (1.8 days).
Average UV index in May
John, French Guiana
- Average UV index in May: 6
The months with the highest UV index are July, August, September, October and November (UV index 7).
The months with the lowest UV index are January, February, March, April, May, June and December (UV index 6).
Average cloud cover in May
John, French Guiana
- Average cloud cover in May: 58
The month with the most cloud cover is February (Cloud cover 62).
The month with the least cloud cover is September (Cloud cover 34).
Average visibility in May
John, French Guiana
- Average visibility in May: 8km
The months with the highest visibility are February, March and April (9km).
The months with the lowest visibility are June, July and August (7km).





