, affected by altitude, with dry, mild winters (but during which it can get cold at night), and very hot, sunny summers. In addition, the climate is subject to sudden changes in temperature.
The city is located in north-central Argentina, at 31 degrees south latitude, and 650 meters (2,130 feet) above sea level.
Due to its location in a valley, with the Andes to the west and mountains to the north-east that exceed 3,000 meters (9,800 feet), the climate is particularly arid. However, thunderstorms can sometimes break out in the summer.
, from late May to mid-August, the difference in temperature between night and day is often noticeable, and, night frosts are quite frequent. During outbreaks cold air from the south, the temperature can drop to -5 °C (23 °F) or below at night and can remain around 8/10 °C (46/50 °F) during the day. In July 2011, it dropped to -9 °C (16 °F).
Since winter is dry, snow in San Juan is rare, however, light snowfalls may occur from time to time, such as in the months of July of 2000, 2007 and 2010.
On the other hand, the wind that comes down from the mountains, called Zonda and similar to the Föhn and the Chinook, is able to raise the temperature by several degrees, it is no coincidence that the heat records exceed 30 °C (86 °F) even in winter.
In spring, starting from mid-August, the temperature rises, and despite the altitude it can get very hot. Furthermore, in
, from December to February, there can be heat waves, during which the temperature can sometimes reach 45 °C (113 °F). Even in summer, however, there can be outbursts of cool air from the south, perhaps accompanied by a thunderstorm, which can greatly lower the temperature for two or three days, so much so that at night it can be very cool even in midsummer.
It is difficult to find the best time to visit San Juan, as summer is very hot, while in winter there can be sudden changes in temperature, moreover, at night it is usually cold, and there can be quite intense frosts. You can then choose the period
. Here are the average temperatures.
January, the hottest month of the year, is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
27.4 °C, with a minimum of
19.8 °C and a maximum of
35.1 °C.
On the coldest nights of the month, the temperature usually drops to around
13.5 °C. However, it dropped to
9 °C in January 2019.
On the warmest days of the month, the temperature usually reaches around
41.5 °C. However, it reached
45.4 °C in January 2003.
Precipitation amounts to
17.4 mm, distributed over 3 days.
The day lasts on average 13 hours and 55 minutes.
There are on average 10 hours of sunshine per day. So, the sun shines 73% of the time.
The average humidity is 40%.
The average wind speed is of
16.4 kph.
February is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
25.8 °C, with a minimum of
18.4 °C and a maximum of
33.3 °C.
On the coldest nights of the month, the temperature usually drops to around
12 °C. However, it dropped to
8.1 °C in February 2003.
On the warmest days of the month, the temperature usually reaches around
40 °C. However, it reached
44.6 °C in February 2001.
Precipitation amounts to
22.5 mm, distributed over 2 days.
The day lasts on average 13 hours and 10 minutes.
There are on average 10 hours of sunshine per day. So, the sun shines 74% of the time.
The average humidity is 44%.
The average wind speed is of
15.1 kph.
March is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
23.3 °C, with a minimum of
16.1 °C and a maximum of
30.5 °C.
On the coldest nights of the month, the temperature usually drops to around
9.5 °C. However, it dropped to
5.6 °C in March 1995.
On the warmest days of the month, the temperature usually reaches around
37.5 °C. However, it reached
42.1 °C in March 2002.
Precipitation amounts to
10.8 mm, distributed over 2 days.
The day lasts on average 12 hours and 10 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 72% of the time.
The average humidity is 49%.
The average wind speed is of
13.4 kph.
April is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of
18.1 °C, with a minimum of
10.9 °C and a maximum of
25.3 °C.
On the coldest nights of the month, the temperature usually drops to around
4 °C. However, it dropped to
-1.6 °C in April 2012.
On the warmest days of the month, the temperature usually reaches around
32.5 °C. However, it reached
39.3 °C in April 2002.
Precipitation amounts to only
4.6 mm, and all occurs in one day.
The day lasts on average 11 hours and 20 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 53%.
The average wind speed is of
11.6 kph.
May is generally a mild month. However, there are remarkable differences between night and day. The average temperature is of
13.2 °C, with a minimum of
6 °C and a maximum of
20.5 °C.
On the coldest nights of the month, the temperature usually drops to around
-0.5 °C. However, it dropped to
-4.1 °C in May 1993.
On the warmest days of the month, the temperature usually reaches around
28 °C. However, it reached
37.4 °C in May 1997.
Precipitation amounts to only
3.4 mm, and all occurs in one day.
The day lasts on average 10 hours and 30 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 66% of the time.
The average humidity is 58%.
The average wind speed is of
9.5 kph.
June is generally a mild month. However, there are remarkable differences between night and day. The average temperature is of
9.4 °C, with a minimum of
1.5 °C and a maximum of
17.3 °C.
On the coldest nights of the month, the temperature usually drops to around
-4.5 °C. However, it dropped to
-7.5 °C in June 2011.
On the warmest days of the month, the temperature usually reaches around
26.5 °C. However, it reached
35 °C in June 2015.
Precipitation amounts to only
1.8 mm, distributed over 0 days.
The day lasts on average 10 hours and 5 minutes. June 21, the winter solstice, is the shortest day of the year in the Southern Hemisphere.
There are on average 6.5 hours of sunshine per day. So, the sun shines 66% of the time.
The average humidity is 55%.
The average wind speed is of
9.6 kph.
July, the coldest month of the year, is generally a quite mild month. However, there are remarkable differences between night and day. The average temperature is of
8.5 °C, with a minimum of
0.3 °C and a maximum of
16.7 °C.
On the coldest nights of the month, the temperature usually drops to around
-5.5 °C. However, it dropped to
-9 °C in July 2011.
On the warmest days of the month, the temperature usually reaches around
26 °C. However, it reached
33.4 °C in July 2006.
Precipitation amounts to only
1.3 mm, distributed over 0 days.
The day lasts on average 10 hours and 20 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 71% of the time.
The average humidity is 50%.
The average wind speed is of
10.4 kph.
August is generally a mild month. However, there are remarkable differences between night and day. The average temperature is of
11.5 °C, with a minimum of
2.7 °C and a maximum of
20.3 °C.
On the coldest nights of the month, the temperature usually drops to around
-3.5 °C. However, it dropped to
-7.2 °C in August 1991.
On the warmest days of the month, the temperature usually reaches around
31 °C. However, it reached
38.5 °C in August 2015.
Precipitation amounts to only
2.6 mm, distributed over 0 days.
The day lasts on average 11 hours and 0 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 73% of the time.
The average humidity is 40%.
The average wind speed is of
11.9 kph.
September is generally a very mild month. However, there are remarkable differences between night and day. The average temperature is of
15.2 °C, with a minimum of
6.6 °C and a maximum of
23.8 °C.
On the coldest nights of the month, the temperature usually drops to around
-0.5 °C. However, it dropped to
-4.1 °C in September 2013.
On the warmest days of the month, the temperature usually reaches around
34 °C. However, it reached
40.8 °C in September 2013.
Precipitation amounts to only
3.7 mm, and all occurs in one day.
The day lasts on average 12 hours and 0 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 70% of the time.
The average humidity is 36%.
The average wind speed is of
13.7 kph.
October is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of
19.6 °C, with a minimum of
11.3 °C and a maximum of
27.9 °C.
On the coldest nights of the month, the temperature usually drops to around
4 °C. However, it dropped to
1 °C in October 1991.
On the warmest days of the month, the temperature usually reaches around
37 °C. However, it reached
42.5 °C in October 2009.
Precipitation amounts to only
2.9 mm, and all occurs in one day.
The day lasts on average 12 hours and 55 minutes.
There are on average 9.5 hours of sunshine per day. So, the sun shines 73% of the time.
The average humidity is 36%.
The average wind speed is of
16 kph.
November is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
23.3 °C, with a minimum of
15 °C and a maximum of
31.6 °C.
On the coldest nights of the month, the temperature usually drops to around
7.5 °C. However, it dropped to
2.5 °C in November 2014.
On the warmest days of the month, the temperature usually reaches around
39.5 °C. However, it reached
44.5 °C in November 2009.
Precipitation amounts to only
7.2 mm, and all occurs in one day.
The day lasts on average 13 hours and 50 minutes.
There are on average 10.5 hours of sunshine per day. So, the sun shines 76% of the time.
The average humidity is 35%.
The average wind speed is of
17.2 kph.
December is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of
26.2 °C, with a minimum of
18 °C and a maximum of
34.4 °C.
On the coldest nights of the month, the temperature usually drops to around
10.5 °C. However, it dropped to
6 °C in December 2014.
On the warmest days of the month, the temperature usually reaches around
41.5 °C. However, it reached
45.7 °C in December 1995.
Precipitation amounts to
12.4 mm, distributed over 2 days.
The day lasts on average 14 hours and 10 minutes. So the days are long. December 21, the summer solstice, is the longest day of the year in the Southern Hemisphere.
There are on average 10.5 hours of sunshine per day. So, the sun shines 73% of the time.
The average humidity is 36%.
The average wind speed is of
17.2 kph.