September weather forecastLa Unión, Guatemala

September

Weather in September

September, the first month of the autumn in La Unión, is also a moderately hot month, with temperature in the range of an average low of 17.5°C (63.5°F) and an average high of 26°C (78.8°F).

Temperature

September begins with an average high-temperature of a still warm 26°C (78.8°F), reflecting close similarity to the preceding month. During September, La Unión records a consistent average nighttime temperature of 17.5°C (63.5°F).

Humidity

In La Unión, the average relative humidity in September is 90%.

Rainfall

September is the month with the most rainfall in La Unión. Rain falls for 29.2 days and accumulates 261mm (10.28") of precipitation.

Daylight

In September, the average length of the day in La Unión is 12h and 13min.
On the first day of September in La Unión, Guatemala, sunrise is at 05:44 and sunset at 18:08. On the last day of the month, sunrise is at 05:46 and sunset at 17:46 CST.

Sunshine

The average sunshine in September in La Unión is 6.7h.

UV index

In September, the average daily maximum UV index is 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV radiation for the ordinary person.
Note: In September, the maximum UV index of 5 suggests these recommendations:
Heed the precautions - Suggestions to avoid sunburn are made. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Experience reduced UV exposure by about half when donning a wide-brim hat.

Updated: Feb 15, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

During September, La Unión experiences an average high-temperature of 26°C (78.8°F) and a low-temperature of 17.5°C (63.5°F). The average heat index (a.k.a. 'real feel', 'apparent temperature'), which combines relative humidity and air temperature, in May is evaluated at 31°C (87.8°F).

The average relative humidity in September in La Unión is 90%.

September is the month with the most rainfall. Rain falls for 29.2 days and accumulates 261mm (10.28") of precipitation.

In La Unión, in September, it is raining for 29.2 days, with typically 261mm (10.28") of accumulated precipitation.

In September, the average day length in La Unión is 12h and 13min.

On the first day of September, sunrise is at 05:44 and sunset at 18:08. On the last day of the month, sunrise is at 05:46 and sunset at 17:46 CST.

In La Unión, the average sunshine duration in September is 6.7h.

In La Unión, Guatemala, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a moderate vulnerability from unsafe exposure to Sun's UV rays.

Today

Tomorrow

Long-term

Year J F M A M J J A September O N D

Aug

September

Oct

Average high temperature

26.2°C

26°C

24.5°C

Average low temperature

Average pressure

Average wind speed

Average max. wind speed

5.6km/h

5km/h

6.3km/h

Average wind speed gusts

Average humidity

Average rainfall

Average rainfall days

Average daylight

Average sunshine

Average sunshine days

1.7

0.7

1.8

Average UV index

Average cloud cover

Average visibility

Average temperature in September
La Unión, Guatemala

Average high temperature in September: 26°C

The warmest month (with the highest average high temperature) is April (28.8°C).
The month with the lowest average high temperature is January (21.8°C).

Average low temperature in September: 17.5°C

The month with the highest average low temperature is May (18.6°C).
The coldest month (with the lowest average low temperature) is January (14.1°C).

Average pressure in September
La Unión, Guatemala

Average pressure in September: 1012.2mbar

The month with the highest atmospheric pressure is January (1015.9mbar).
The months with the lowest atmospheric pressure are May and September (1012.2mbar).

Average wind speed in September
La Unión, Guatemala

Average wind speed in September: 4.4km/h

The windiest month (with the highest average wind speed) is January (7.8km/h).
The calmest month (with the lowest average wind speed) is September (4.4km/h).

Average humidity in September
La Unión, Guatemala

Average humidity in September: 90%

The months with the highest relative humidity are October and November (91%).
The month with the lowest relative humidity is April (76%).

Average rainfall in September
La Unión, Guatemala

Average rainfall in September: 261mm

The wettest month (with the highest rainfall) is September (261mm).
The driest month (with the least rainfall) is February (32mm).

Average rainfall days in September
La Unión, Guatemala

Average rainfall days in September: 29.2 days

The month with the highest number of rainy days is September (29.2 days).
The month with the least rainy days is February (19.1 days).

Average daylight in September /
Average sunshine in September
La Unión, Guatemala

Average daylight in September: 12h and 12min

The month with the longest days is June (Average daylight: 13h and 0min).
The month with the shortest days is December (Average daylight: 11h and 18min).

Average sunshine in September: 6h and 42min

The month with the most sunshine is April (Average sunshine: 10h and 18min).
The month with the least sunshine is November (Average sunshine: 5h and 0min).

Average sunshine days in September
La Unión, Guatemala

Average sunshine days in September: 0.7 days

The month with the most sunshine days is March (8.3 days).
The month with the least sunshine days is September (0.7 days).

Average UV index in September
La Unión, Guatemala

Average UV index in September: 5

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