April weather forecastSan Juan, PR
April
Weather in April
April invites a new chapter of weather in San Juan. The increase to 81.1°F (27.3°C) in average high temperatures accompanies a rise in sea temperatures to 80.5°F (26.9°C), signaling the onset of a warmer climate. Sunshine hours continue to increase, yet cloud cover remains relatively constant. Notably, daylight hours exceed half the day for the first time in the year, averaging 12.6 hours. This progression into the warmer months further enhances the city’s appeal to sightseers and tourists.Temperature
As San Juan transitions into April, the average high-temperature stands at a still warm 81.1°F (27.3°C), offering little variation from the preceding month. In April, San Juan temperatures settle at a low of 75.2°F (24°C) during the nights, reflecting a minor change from daytime highs.Heat index
For most parts of April, the heat index is estimated at a hot 86°F (30°C). Long-lasting exposure and activity potentially induce a sense of weariness, with the risk of heat cramps.It is important to note that the heat index values are for shaded areas and light wind scenarios. The heat index has the potential to rise by 15 Fahrenheit (8 Celsius) degrees with direct sunshine exposure.
Note: The heat index, also known as 'real feel' or 'feels like', shows a temperature sensation when both heat and moisture conditions are combined. One's perception of temperature can vary depending on physical activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. Being under direct sunshine can magnify the heat experience, possibly pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Children often lack awareness of the importance of taking breaks and rehydrating. The feeling of thirst is a late indication of dehydration, so maintaining hydration, especially during long periods of physical activity, is critical.
Humidity
In San Juan, Puerto Rico, the average relative humidity in April is 77%.Rainfall
The month with the least rainfall is April, when the rain falls for 12.4 days and typically collects 0.55" (14mm) of precipitation.Ocean temperature
In April, the average ocean temperature is 80.4°F (26.9°C).Note: Water temperatures from 77°F (25°C) to 84.2°F (29°C) make swimming, diving, and similar activities highly pleasurable and enjoyable for long periods without discomfort.
Daylight
The average length of the day in April is 12h and 34min.On the first day of the month, sunrise is at 6:17 am and sunset at 6:38 pm. On the last day of April, sunrise is at 5:57 am and sunset at 6:45 pm AST.
Sunshine
In San Juan, Puerto Rico, the average sunshine in April is 9.1h.UV index
The months with the highest UV index are April through November, 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 average individuals.Note: In April, the maximum UV index of 7 suggests this advice:
Employ safeguards and advocate sun safety protocols. Shielding against skin and eye damage is crucial. Avoid direct Sun exposure and seek shade from 10 a.m. to 4 p.m., the period of highest UV radiation. Remember, however, that not all shade structures offer full protection. By wearing a generously brimmed hat, you can cut UV radiation exposure significantly. Attention! UV radiation is markedly stronger with water and sand reflections.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in April
San Juan, PR
- Average high temperature in April: 81.1°F
The warmest month (with the highest average high temperature) is August (85.1°F).
The months with the lowest average high temperature are January and March (79.9°F).
- Average low temperature in April: 75.2°F
The months with the highest average low temperature are August, September and October (79.2°F).
The coldest month (with the lowest average low temperature) is March (73.9°F).
Average pressure in April
San Juan, PR
- Average pressure in April: 29.99"Hg
The months with the highest atmospheric pressure are January and February (30.02"Hg).
The month with the lowest atmospheric pressure is October (29.9"Hg).
Average wind speed in April
San Juan, PR
- Average wind speed in April: 9.4mph
The windiest month (with the highest average wind speed) is July (10.7mph).
The calmest month (with the lowest average wind speed) is October (7.4mph).
Average humidity in April
San Juan, PR
- Average humidity in April: 77%
The months with the highest relative humidity are May, June and July (79%).
The months with the lowest relative humidity are February and March (76%).
Average rainfall in April
San Juan, PR
- Average rainfall in April: 0.55"
The wettest month (with the highest rainfall) is November (1.57").
The driest month (with the least rainfall) is April (0.55").
Average rainfall days in April
San Juan, PR
- Average rainfall days in April: 12.4 days
The month with the highest number of rainy days is November (16.1 days).
The month with the least rainy days is June (10.3 days).
Average sea temperature in April
San Juan, PR
- Average sea temperature in April: 80.5°F
The best month for swimming (with the highest average sea temperature) is September (84.9°F).
The coldest month (with the lowest average sea temperature) is February (78.9°F).
Average daylight in April /
Average sunshine in April
San Juan, PR
- Average daylight in April: 12h and 36min
The month with the longest days is June (Average daylight: 13h and 12min).
The month with the shortest days is December (Average daylight: 11h and 0min).
- Average sunshine in April: 9h and 6min
The month with the most sunshine is June (Average sunshine: 10h and 54min).
The month with the least sunshine is December (Average sunshine: 6h and 36min).
Average sunshine days in April
San Juan, PR
- Average sunshine days in April: 11 days
The month with the most sunshine days is June (13.7 days).
The month with the least sunshine days is November (9.4 days).
Average UV index in April
San Juan, PR
- Average UV index in April: 7
The months with the highest UV index are April, May, June, July, August, September, October and November (UV index 7).
The months with the lowest UV index are January, February, March and December (UV index 6).
Average cloud cover in April
San Juan, PR
- Average cloud cover in April: 30
The month with the most cloud cover is December (Cloud cover 35).
The month with the least cloud cover is September (Cloud cover 26).
Average visibility in April
San Juan, PR
- Average visibility in April: 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).
