September weather forecast
Mazatlán, Mexico

For Mazatlán, September brings a slight relief from the heavy rainfall of August. But that does not mean the city's streets become dry - the city still records quite substantial downpours of 121mm (4.76") across 23.1 days. The decreased rainfall rejuvenates outdoor activities, drawing residents back to the streets and parks. The high humidity surrounding these rains makes it a bit uncomfortable. However, September is also marked by an inviting warm sea, ideal for all sorts of water activities.

Temperature

A minor adjustment in Mazatlán's average high-temperature is noted with the start of September, touching a still tropical 30.3°C (86.5°F) from August's 30.9°C (87.6°F). In Mazatlán, nights during September observe an average temperature decrease to a moderately hot 26.3°C (79.3°F).

Heat index

September's heat index is appraised at a sweltering 38°C (100.4°F). Exercise increased caution, heat cramps and heat exhaustion are potential hazards. Continuous activity could lead to heatstroke.
It is worth noting that heat index values are gauged for conditions in the shade and light breezes. The heat index could see an increase by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'feels like' or 'felt air temperature', is derived by integrating air temperature with the existing relative humidity to express the perceived warmth. An individual's temperature experience can be influenced by extra factors, including metabolic differences, activity levels, and clothing. Be mindful that being in direct sunlight might mean feeling hotter, with the heat index rising by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for children. Young children are generally more endangered than adults, as they usually less sweat. And also, due to larger skin surface relative to their small bodies and higher heat production as a result of their activity.
Perspiration, followed by sweat evaporation, is the human body's chief method to maintain a balanced temperature. In circumstances of high air temperature and humidity (high heat index), the body's perspiration is restricted, heightening the feeling of warmth. When body temperature rises due to excess heat gain beyond its removal capability, one might experience heat-related disorders.

Humidity

September is the most humid month, with an average relative humidity of 77%.

Rainfall

September is the month with the most rainfall. Rain falls for 23.1 days and accumulates 121mm (4.76") of precipitation.

Sea temperature

In Mazatlán, in September, the average water temperature is 30.5°C (86.9°F).
Note: Cooling down in waters with temperatures over 30°C (86°F) might not feel as satisfying.

Daylight

In September, the average length of the day in Mazatlán is 12h and 16min.
On the first day of the month, sunrise is at 5:48 am and sunset at 6:22 pm. On the last day of September, sunrise is at 5:57 am and sunset at 5:53 pm MST.

Sunshine

In Mazatlán, the average sunshine in September is 10.7h.

UV index

May through October, with an average maximum UV index of 7, are months with the highest UV index in Mazatlán. A UV Index of 6 to 7 symbolizes a high health hazard from unsafe exposure to UV radiation for ordinary individuals.
Note: The UV index of 7 during September leads to these advisories:
Shun overexposure. Protection from sun ravages is indispensable. Avoid direct Sun exposure and seek shade between 10 a.m. and 4 p.m., when UV radiation is at its peak, but keep in mind that not all shade structures provide complete protection. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Be wary! Reflections from sand and water make UV radiation more intense.