September weather forecastAlter do Chão, Portugal
September weather for Alter do Chão, Portugal: September, the first month of the autumn in Alter do Chão, is also a moderately hot month, with an average temperature varying between 29.4°C (84.9°F) and 16.3°C (61.3°F). On the last day of September, in Alter do Chão, sunrise is at 07:26 and sunset at 19:14 WEST.
September
Weather in September
September, the first month of the autumn in Alter do Chão, is also a moderately hot month, with an average temperature varying between 29.4°C (84.9°F) and 16.3°C (61.3°F).Temperature
As August transitions into September, Alter do Chão sees a gentle drop in the average high-temperature, transitioning from a tropical 33.3°C (91.9°F) to a moderately hot 29.4°C (84.9°F). In Alter do Chão, a significant divergence from daytime highs is recorded, with average lows of 16.3°C (61.3°F) during September nights.Heat index
Throughout September, the heat index is evaluated at a hot 30°C (86°F). Long-lasting exposure and activity potentially induce a sense of weariness, with the risk of heat cramps.Heat index data is primarily for areas with shade and subjected to light winds. The heat index could see an increase by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'apparent temperature' or 'real feel', embodies the combination of air temperature and moisture content to illustrate perceived heat. The impact of weather is individual, with diverse individuals experiencing it differently due to variations in body mass, height, and activity levels. One must note that being under the direct sun can escalate the heat's effects, with the heat index possibly rising by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. 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.
Humidity
In Alter do Chão, Portugal, the average relative humidity in September is 48%.Rainfall
In Alter do Chão, in September, during 4.8 rainfall days, 8mm (0.31") of precipitation is typically accumulated. Throughout the year, in Alter do Chão, Portugal, there are 78.7 rainfall days, and 219mm (8.62") of precipitation is accumulated.Snowfall
In Alter do Chão, snow does not fall in April through December.Daylight
The average length of the day in September in Alter do Chão is 12h and 26min.On the first day of the month, sunrise is at 06:59 and sunset at 20:01. On the last day of September, in Alter do Chão, sunrise is at 07:26 and sunset at 19:14 WEST.
Sunshine
In September, the average sunshine in Alter do Chão is 9.5h.UV index
In September, the average daily maximum UV index is 6. A UV Index estimate of 6 to 7 represents a high health vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum UV index of 6 during September leads to these instructions:
Persist in precautions and follow sun safety policies. Keeping sunburn at bay is imperative. Seek shade and limit direct Sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its peak, but be aware that not all shade structures provide complete sun protection. Experience reduced UV exposure by about half when donning a wide-brim hat.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Alter do Chão, Portugal
- Average high temperature in September: 29.4°C
The warmest month (with the highest average high temperature) is August (33.3°C).
The month with the lowest average high temperature is January (11.9°C).
- Average low temperature in September: 16.3°C
The month with the highest average low temperature is August (17.7°C).
The coldest month (with the lowest average low temperature) is January (4.2°C).
Average pressure in September
Alter do Chão, Portugal
- Average pressure in September: 1016.3mbar
The month with the highest atmospheric pressure is December (1023mbar).
The month with the lowest atmospheric pressure is April (1015.2mbar).
Average wind speed in September
Alter do Chão, Portugal
- Average wind speed in September: 8.4km/h
The windiest month (with the highest average wind speed) is February (12.1km/h).
The calmest month (with the lowest average wind speed) is September (8.4km/h).
Average humidity in September
Alter do Chão, Portugal
- Average humidity in September: 48%
The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is August (43%).
Average rainfall in September
Alter do Chão, Portugal
- Average rainfall in September: 8mm
The wettest month (with the highest rainfall) is November (39mm).
The driest month (with the least rainfall) is July (3mm).
Average rainfall days in September
Alter do Chão, Portugal
- Average rainfall days in September: 4.8 days
The month with the highest number of rainy days is April (11.7 days).
The month with the least rainy days is July (1.7 days).
Average snowfall in September
Alter do Chão, Portugal
- Average snowfall in September: 0mm
The month with the highest snowfall is February (5mm).
The months with the least snowfall are April, May, June, July, August, September, October, November and December (0mm).
Average snowfall days in September
Alter do Chão, Portugal
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (0.4 days).
The months with the least snowfall days are April, May, June, July, August, September, October, November and December (0 days).
Average daylight in September /
Average sunshine in September
Alter do Chão, Portugal
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 9h and 30min
The months with the most sunshine are July and August (Average sunshine: 11h and 48min).
The month with the least sunshine is January (Average sunshine: 5h and 6min).
Average sunshine days in September
Alter do Chão, Portugal
- Average sunshine days in September: 24 days
The month with the most sunshine days is July (28.7 days).
The month with the least sunshine days is April (16.6 days).
Average UV index in September
Alter do Chão, Portugal
- Average UV index in September: 6
The month with the highest UV index is August (UV index 7).
The months with the lowest UV index are January, February, March, November and December (UV index 3).
Average cloud cover in September
Alter do Chão, Portugal
- Average cloud cover in September: 16
The month with the most cloud cover is January (Cloud cover 42).
The months with the least cloud cover are July and August (Cloud cover 8).
Average visibility in September
Alter do Chão, Portugal
- Average visibility in September: 10km
The months with the highest visibility are June, July, August and September (10km).
The month with the lowest visibility is January (8km).
