September weather forecastCusco, Peru

September
Weather in September
September marks a gradual transition from the dry to the wet season in Cusco, Peru. Rainfall starts to rise, but remains relatively low at 22mm (0.87"), reserved for a minor 7 days in the month. As the return of the rainy season becomes more evident, there's a noticeable rise in humidity. Nevertheless, the weather remains comfortable for exploring local attractions, ensuring Cusco remains a popular stop for tourists. Although the UV index begins to drop, protection against sun exposure is still advised.Temperature
The unfolding of September in Cusco shows an average high-temperature of a pleasant 20.1°C (68.2°F), indicating a slight variance from August's 19.9°C (67.8°F). Cusco registers a significant drop in temperature in September, with average nighttime lows of 4°C (39.2°F).Humidity
In Cusco, the average relative humidity in September is 51%.Rainfall
In September, in Cusco, the rain falls for 7 days. Throughout September, 22mm (0.87") of precipitation is accumulated. In Cusco, during the entire year, the rain falls for 102 days and collects up to 708mm (27.87") of precipitation.Daylight
The average length of the day in September is 12h and 2min.On the first day of September in Cusco, sunrise is at 05:51 and sunset at 17:43. On the last day of the month, sunrise is at 05:31 and sunset at 17:44 -05.
Sunshine
In September, the average sunshine is 6.5h.UV index
The months with the highest UV index in Cusco are January through April, August through December, with an average maximum UV index of 12. A UV Index estimate of 11, and higher, represents an extreme threat to health from unsafe exposure to UV radiation for the ordinary person.Note: In September, the maximum UV index of 12 suggests these recommendations:
Enforce all necessary safety measures, unprotected skin may suffer burns swiftly. Avoid direct Sun exposure and stay in the shade between 10 a.m. and 4 p.m., a time when UV radiation is most intense, noting that not all shade structures offer full protection. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Cusco, Peru
- Average high temperature in September: 20.1°C
The warmest month (with the highest average high temperature) is October (20.9°C).
The months with the lowest average high temperature are January and February (18.8°C).
- Average low temperature in September: 4°C
The months with the highest average low temperature are January and February (6.6°C).
The coldest month (with the lowest average low temperature) is July (0.2°C).
Average humidity in September
Cusco, Peru
- Average humidity in September: 51%
The month with the highest relative humidity is February (66%).
The month with the lowest relative humidity is August (46%).
Average rainfall in September
Cusco, Peru
- Average rainfall in September: 21.8mm
The wettest month (with the highest rainfall) is January (145.3mm).
The driest month (with the least rainfall) is June (1.5mm).
Average rainfall days in September
Cusco, Peru
- Average rainfall days in September: 7 days
The month with the highest number of rainy days is January (18 days).
The months with the least rainy days are June, July and August (2 days).
Average daylight in September /
Average sunshine in September
Cusco, Peru
- Average daylight in September: 12h and 0min
The month with the longest days is December (Average daylight: 12h and 54min).
The month with the shortest days is June (Average daylight: 11h and 18min).
- Average sunshine in September: 6h and 30min
The month with the most sunshine is July (Average sunshine: 8h and 18min).
The month with the least sunshine is February (Average sunshine: 4h and 18min).
Average UV index in September
Cusco, Peru
- Average UV index in September: 12
The months with the highest UV index are January, February, March, April, August, September, October, November and December (UV index 12).
The months with the lowest UV index are June and July (UV index 10).








