April weather forecast
Ha Long, Vietnam

April’s weather in Ha Long marks the shift towards steadily warming days. A significant amount of rainfall has been recorded at 53mm (2.09") in April, indicating the progression into the rainy season. The region's natural beauty flourishes, captivating visitors with its verdant landscapes. Sea temperatures elevate, maintaining a pleasant balance with the rising onshore temperatures. As the precipitation increases, so does the vibrant ecosystem of this Vietnamese city.

Temperature

The onset of April in Ha Long marks a slight increase in the average high-temperature, moving from a warm 26.8°C (80.2°F) in March to a hot 30.6°C (87.1°F). During April, Ha Long records a consistent average nighttime temperature of 21.4°C (70.5°F).

Heat index

The heat index value for April is appraised at a torrid 38°C (100.4°F). Adopt extra safety steps, risk of heat exhaustion and heat cramps is notable. Sustained activity might cause heatstroke.
Heat index values are typically calculated for conditions of shade and a light breeze. Direct sunlight has the potential to heighten heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', melds the effects of warmth and moisture to generate a feeling of heat. Factors encompassing physical activity, clothing, and metabolic differences have a role in shaping the individual's impression of temperature. Bear in mind that direct sunshine exposure increases weather impact, and may raise heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely vital to babies and toddlers. Typically, children face more danger than adults as they usually perspire less. Their larger skin surface relative to their small bodies and increased heat output from their activities enhance their risk.
The human body normally cools itself by perspiration, as evaporated sweat carries heat away from the body. When air moisture content is high, the cooling process through evaporation is not as efficient, leading to an ineffective body cooling process and a feeling of overheating. Overheating and potential dehydration arise when body heat gain eclipses its release capability.

Humidity

In April, the average relative humidity in Ha Long is 76%.

Rainfall

In Ha Long, during April, the rain falls for 20.3 days and regularly aggregates up to 53mm (2.09") of precipitation. Throughout the year, there are 237.1 rainfall days, and 1472mm (57.95") of precipitation is accumulated.

Sea temperature

In Ha Long, in April, the average water temperature is 22.4°C (72.3°F).
Note: For someone not comfortable with cold, swimming in 22.4°C (72.3°F) waters might be a stretch. However, with favorable conditions like abundant sunshine, mild wind, and warm air temperatures, the experience can be improved. And while wetsuits are not a must, they can be considered.

Daylight

In April, the average length of the day in Ha Long is 12h and 38min.
On the first day of the month, sunrise is at 05:44 and sunset at 18:06. On the last day of April, in Ha Long, sunrise is at 05:21 and sunset at 18:16 +07.

Sunshine

In Ha Long, the average sunshine in April is 7.8h.

UV index

The months with the highest UV index are April through August, with an average maximum UV index of 7. A UV Index reading of 6 to 7 represents a high threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: The maximum UV index, 7 during April, leads to the following recommendations:
Evade overexposure. Individuals with fair skin risk burning in under 20 minutes. Limit your exposure to the sun's UV radiation, which is strongest between 10 a.m. and 4 p.m., and note that parasols or canopies may not provide full sun protection. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses. Warning! The Sun's UV rays intensify with reflections from sand and water.