September weather forecast
Nuevo Vallarta, Mexico

September observes a moderate decrease with temperatures ranging between 21.8°C (71.2°F) and 28.5°C (83.3°F). Humidity stays high at 84%, keeping the environment humid and typically tropical. Rainfall remains considerable at 144mm (5.67") but slightly less than in August, falling over 24 days. As the month progresses, sunshine continues for 8.4 hours a day, holding on against the monsoon. Commendably, the visibility holds steady at 10km (6.2mi), supporting interrupted tours.

Temperature

September ushers in an average high-temperature of a still warm 28.5°C (83.3°F), aligning closely with the preceding month. During September nights, Nuevo Vallarta records an average temperature of 21.8°C (71.2°F).

Heat index

September's average heat index is evaluated at a tropical 34°C (93.2°F). Undertake special precautions, the probability of heat exhaustion and heat cramps is high. Prolonged activity may provoke heatstroke.
Data suggests that the heat index is set for environments in shade and with a light wind. Exposure to unobstructed sunshine could lead to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', measures the perceived warmth when incorporating the humidity present in the air. Depending on the activity and the individual's heat perception, which may vary due to factors including wind, clothing, and metabolic variations, this effect remains subjective. You should know that direct sun exposure can heighten weather effects, potentially elevating the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to children. Young individuals are generally in more danger than adults due to their lower capacity to sweat. Moreover, their large skin surface in relation to their small bodies and the increased heat generation from their activities makes them more vulnerable.

Humidity

August and September, with an average relative humidity of 84%, are the most humid months in Nuevo Vallarta.

Rainfall

In Nuevo Vallarta, in September, during 24.4 rainfall days, 144mm (5.67") of precipitation is typically accumulated. Throughout the year, there are 153.3 rainfall days, and 735mm (28.94") of precipitation is accumulated.

Daylight

In September, the average length of the day in Nuevo Vallarta is 12h and 15min.
On the first day of September, sunrise is at 6:45 am and sunset at 7:16 pm. On the last day of the month, sunrise is at 6:52 am and sunset at 6:49 pm CST.

Sunshine

August and September, with an average of 8.4h of sunshine, are months with the least sunshine.

UV index

January through November, with an average maximum UV index of 6, are months with the highest UV index in Nuevo Vallarta. A UV Index estimate of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV rays for the average person.
Note: A daily maximum UV index of 6 in September translates into the following instructions:
Guard against overexposure. Protection from sun-induced harm is essential. The hours from 10 a.m. to 4 p.m. have the most intense UV radiation. As much as possible, limit direct sun exposure during this period. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration.