September weather forecast
Lao Cai, Vietnam

The arrival of September in Lao Cai, Vietnam, brings a notable drop in rainfall from the preceding August and the weather pattern begins to shift towards drier conditions. It strikingly receives just over a third of August's rainfall, recording 69mm (2.72") over 20.4 days. Temperature measurements, on the other hand, show only slight changes, upholding the warmth of the tropical region. Sunshine hours begin to rise from the August readings, suggesting a clearer sky in the offing. Progressing into October, there's a further reduction in rainfall and a steady drop in temperature, marking the onset of the cooler period.

Temperature

Lao Cai experiences an average high-temperature of a still hot 30°C (86°F) in September, marking an insignificant shift from 31°C (87.8°F) in August. Lao Cai throughout September, experiences an average nighttime temperature of 18.7°C (65.7°F).

Heat index

For September, the heat index is calculated to be a sweltering 37°C (98.6°F). Preventive measures are required to mitigate the risk of heat cramps and heat exhaustion. Continuous activity may precipitate heatstroke.
Heat index values are typically calculated for conditions of shade and a light breeze. 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 'apparent temperature' or 'felt air temperature', is a calculation that merges air temperature and relative humidity to depict the sensation of warmth. The individual's impression of temperature can be affected by numerous factors such as metabolic variations, physical exertion, and attire. In direct sunlight, the heat's impact can be heightened, potentially leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to babies and toddlers. Children frequently underestimate the necessity to rest and hydrate. Thirst is a late sign of dehydration - thus, it is vital to stay hydrated, particularly during lengthy physical exercises.
To cool down, the human body relies on perspiration, a process where excessive heat is eliminated as sweat evaporates. Elevated relative humidity diminishes evaporation, thereby reducing the body's ability to shed heat and creating a feeling of being too warm. Elevated heat gain compared to the body's release capability poses risks of dehydration and potential overheating.

Humidity

In September, the average relative humidity is 77%.

Rainfall

In Lao Cai, in September, it is raining for 20.4 days, with typically 69mm (2.72") of accumulated precipitation. In Lao Cai, during the entire year, the rain falls for 188.3 days and collects up to 770mm (30.31") of precipitation.

Daylight

In September, the average length of the day is 12h and 17min.
On the first day of September, sunrise is at 05:46 and sunset at 18:20. On the last day of the month, sunrise is at 05:54 and sunset at 17:52 +07.

Sunshine

The average sunshine in September is 10.2h.

UV index

The months with the highest UV index are March through September, with an average maximum UV index of 6. A UV Index reading of 6 to 7 represents a high health risk from unprotected exposure to Sun's UV rays for the average person.
Note: The maximum UV index of 6 during September leads to these instructions:
Ward off overexposure. Defence against solar harm is crucial. The Sun's UV radiation is at its strongest between the hours of 10 a.m. and 4 p.m. Minimize direct exposure to the sun during this period. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.