September weather forecastAlte, Portugal

September

Weather in September

September, the first month of the autumn in Alte, is still a warm month, with an average temperature ranging between min 18.8°C (65.8°F) and max 25.5°C (77.9°F).

Temperature

Stepping into September, Alte records an average high-temperature of a still moderately hot 25.5°C (77.9°F), almost consistent with August. In the month of September, Alte's average low-temperature falls to a comfortable 18.8°C (65.8°F).

Humidity

The average relative humidity in September in Alte is 67%.

Rainfall

In Alte, during September, the rain falls for 2.8 days and regularly aggregates up to 3mm (0.12") of precipitation. In Alte, during the entire year, the rain falls for 45.8 days and collects up to 63mm (2.48") of precipitation.

Daylight

In September, the average length of the day in Alte is 12h and 25min.
On the first day of the month, sunrise is at 07:03 and sunset at 20:01. On the last day of September, in Alte, Portugal, sunrise is at 07:27 and sunset at 19:17 WEST.

Sunshine

In September, the average sunshine is 9.6h.

UV index

May through September, with an average maximum UV index of 6, are months with the highest UV index. A UV Index reading of 6 to 7 represents a high health hazard from unsafe exposure to UV radiation for ordinary individuals.
Note: A daily high UV index of 6 in September leads to these guidelines:
Deflect overexposure. Sun protection is a necessity. Limit direct sun exposure and seek shade between 10 a.m. and 4 p.m., the time of the most intense UV radiation, noting that shade structures may not provide total sun protection. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes.

Frequently asked questions

In Alte, 25.5°C (77.9°F) is the average high-temperature and 18.8°C (65.8°F) is the average low-temperature during September. In August, the average heat index (a.k.a. 'felt air temperature', 'real feel'), which combines relative humidity and air temperature, is appraised at 30°C (86°F).

The average relative humidity in September is 67%.

In Alte, Portugal, in September, it is raining for 2.8 days, with typically 3mm (0.12") of accumulated precipitation.

In Alte, Portugal, the average day length in September is 12h and 25min.

On the first day of September in Alte, Portugal, sunrise is at 07:03 and sunset at 20:01. On the last day of the month, sunrise is at 07:27 and sunset at 19:17 WEST.

In Alte, the average sunshine duration in September is 9.6h.

The months with the highest UV index in Alte, Portugal, are May through September, with an average maximum UV index of 6.

The average daily maximum UV index in September in Alte, Portugal, is 6. A UV Index reading of 6 to 7 represents a high health threat from exposure to the Sun's UV radiation.
Average high temperature
Average low temperature
Average wind speed
Average max. wind speed
Average wind speed gusts
Average humidity
Average rainfall
Average rainfall days
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Alte, Portugal

  • Average high temperature in September: 25.5°C

The warmest month (with the highest average high temperature) is August (28°C).
The month with the lowest average high temperature is January (14.9°C).

  • Average low temperature in September: 18.8°C

The month with the highest average low temperature is August (19.7°C).
The coldest month (with the lowest average low temperature) is February (10.2°C).

Average pressure in September
Alte, Portugal

  • Average pressure in September: 1016.6mbar

The month with the highest atmospheric pressure is December (1022.5mbar).
The month with the lowest atmospheric pressure is April (1015.5mbar).

Average wind speed in September
Alte, Portugal

  • Average wind speed in September: 12.2km/h

The windiest months (with the highest average wind speed) are February and March (17.5km/h).
The calmest month (with the lowest average wind speed) is September (12.2km/h).

Average humidity in September
Alte, Portugal

  • Average humidity in September: 67%

The month with the highest relative humidity is January (76%).
The month with the lowest relative humidity is August (62%).

Average rainfall in September
Alte, Portugal

  • Average rainfall in September: 3mm

The wettest month (with the highest rainfall) is November (13mm).
The driest month (with the least rainfall) is July (0mm).

Average rainfall days in September
Alte, Portugal

  • Average rainfall days in September: 2.8 days

The month with the highest number of rainy days is April (7.5 days).
The month with the least rainy days is August (0.5 days).

Average daylight in September /
Average sunshine in September
Alte, Portugal

  • Average daylight in September: 12h and 24min

The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 42min).

  • Average sunshine in September: 9h and 36min

The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 6h and 6min).

Average sunshine days in September
Alte, Portugal

  • Average sunshine days in September: 25.9 days

The months with the most sunshine days are July and August (29.8 days).
The month with the least sunshine days is April (20 days).

Average UV index in September
Alte, Portugal

  • Average UV index in September: 6

The months with the highest UV index are May, June, July, August and September (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 4).

Average cloud cover in September
Alte, Portugal

  • Average cloud cover in September: 14

The month with the most cloud cover is January (Cloud cover 31).
The month with the least cloud cover is July (Cloud cover 5).

Average visibility in September
Alte, Portugal

  • Average visibility in September: 10km

The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).