Weather and climate in San Luis (Argentina)

The climate of San Luis is subtropical (Köppen classification: subtropical with dry winters - Cwa), with mild (but sometimes cold at night), dry winters and hot, rainy summers. In summer, rainfall often occurs in the form of thunderstorms.
The city is located in north-central Argentina, at 31 degrees south latitude, and at 715 meters (2,345 feet) above sea level.
About 220 km (135 mi) to the west is the city of Mendoza, which is located at the base of the Andes, while in the vicinity of San Luis we find a smaller mountain range, with peaks reaching 2,200 meters (7,200 ft).
The sun often shines all year round.



In winter, from late May to mid-August, the difference in temperature between night and day is often considerable, and it gets often cold at night. During cold air outbreaks from the south, the temperature can drop a few degrees below freezing. In July 2007, it dropped to -8 °C (17.5 °F).
Sometimes there can also be snowfalls, usually light.
During the day, it can get warm all year round. In winter, the temperature can reach or exceed 25 °C (77 °F) when the northwest wind blows, coming down from the mountains.
On the other hand, from September to February there can be heat waves, in which the temperature reaches or exceeds 38/40 °C (100/104 °F). In July 2014, the temperature reached 42 °C (107.5 °F), and the average maximum was 34.8 °C (94.6 °F).
However, the Pampero, the south wind, is able to interrupt the hot and sultry periods, bringing pleasant weather (and sometimes very cool) for two or three days.

Best Time

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To visit San Luis you can choose the intermediate seasons, in particular, the months of April (autumn), and September (spring). It must be said that there can be sudden changes in temperature, sometimes at night it can get cold, while in September it can be very hot, although rarely, and generally at the end of the month.

San Luis - Climate data

The average temperature of the coldest month (July) is of 10.4 °C (50.6 °F), that of the warmest month (January) is of 25.0 °C (76.9 °F). Here are the average temperatures.
Precipitation amounts to 665 millimeters (26.2 inches) per year: so, it is at an intermediate level. It ranges from 5 mm (0.2 in) in the driest months (June, July) to 115 mm (4.5 in) in the wettest one (January). Here is the average precipitation.
There are on average around 3090 sunshine hours per year. Here are the average hours of sunshine per day.

San Luis - Weather by month

Based on the period 1991-2020

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January, the warmest 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 25.0 °C (77 °F), with a minimum of 18.3 °C (64.9 °F) and a maximum of 31.6 °C (88.9 °F).
On the coldest nights of the month, the temperature usually drops to around 12 °C (53.5 °F).
On the warmest days of the month, the temperature usually reaches around 37 °C (99 °F).
Precipitation amounts to 115 mm (4.5 in), distributed over 8 days.
The day lasts on average 14 hours and 5 minutes. So the days are long.
There are on average 10.5 hours of sunshine per day. So, the sun shines 76% of the time.
The average humidity is 51%.
The average wind speed is 17 kph (10 mph).

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February is generally a warm to hot month. The average temperature is of 23.6 °C (74 °F), with a minimum of 17.2 °C (63 °F) and a maximum of 30 °C (86 °F).
On the coldest nights of the month, the temperature usually drops to around 10 °C (50.5 °F).
On the warmest days of the month, the temperature usually reaches around 36 °C (96.5 °F).
Precipitation amounts to 112 mm (4.4 in), distributed over 7 days.
The day lasts on average 13 hours and 20 minutes.
There are on average 10 hours of sunshine per day. So, the sun shines 74% of the time.
The average humidity is 55%.
The average wind speed is 16 kph (10 mph).

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March is generally a warm month. The average temperature is of 21.6 °C (71 °F), with a minimum of 15.5 °C (59.9 °F) and a maximum of 27.6 °C (81.7 °F).
On the coldest nights, the temperature usually drops to around 9 °C (48 °F).
On the warmest days, the temperature usually reaches around 33.5 °C (92.5 °F).
Precipitation amounts to 92 mm (3.6 in), distributed over 7 days.
The day lasts on average 12 hours and 20 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 68% of the time.
The average humidity is 60%.
The average wind speed is 15 kph (9 mph).

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April is generally a very mild month. The average temperature is of 17.6 °C (64 °F), with a minimum of 11.8 °C (53.2 °F) and a maximum of 23.3 °C (73.9 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 4 °C (39.5 °F).
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 29.5 °C (85.5 °F).
Precipitation amounts to 45 mm (1.8 in), distributed over 4 days.
The day lasts on average 11 hours and 10 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 65% of the time.
The average humidity is 62%.
The average wind speed is 13 kph (8 mph).

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May is generally a mild month. The average temperature is of 14.0 °C (57 °F), with a minimum of 8.3 °C (46.9 °F) and a maximum of 19.6 °C (67.3 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 1 °C (33.5 °F).
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 26 °C (79 °F).
Precipitation amounts to 19 mm (0.7 in), distributed over 3 days.
The day lasts on average 10 hours and 25 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 61% of the time.
The average humidity is 63%.
The average wind speed is 12 kph (8 mph).

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June is generally a mild month. The average temperature is of 11.0 °C (52 °F), with a minimum of 5 °C (41 °F) and a maximum of 17.1 °C (62.8 °F).
On the coldest nights, the temperature usually drops to around -2 °C (28.5 °F).
On the warmest days, the temperature usually reaches around 24.5 °C (75.5 °F).
Precipitation amounts to only 5 mm (0.2 in), and all occurs in one day.
The day lasts on average 10 hours and 0 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 63% of the time.
The average humidity is 59%.
The average wind speed is 12 kph (8 mph).

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July, the coldest month of the year, is generally a mild month. The average temperature is of 10.4 °C (51 °F), with a minimum of 4 °C (39.2 °F) and a maximum of 16.7 °C (62.1 °F).
On the coldest nights of the month, the temperature usually drops to around -2.5 °C (27 °F).
On the warmest days of the month, the temperature usually reaches around 25 °C (77.5 °F).
Precipitation amounts to only 5 mm (0.2 in), and all occurs in one day.
The day lasts on average 10 hours and 10 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 68% of the time.
The average humidity is 52%.
The average wind speed is 14 kph (8 mph).

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August is generally a mild month. However, there are remarkable differences between night and day. The average temperature is of 12.8 °C (55 °F), with a minimum of 6.2 °C (43.2 °F) and a maximum of 19.5 °C (67.1 °F).
On the coldest nights of the month, the temperature usually drops to around -1.5 °C (29 °F).
On the warmest days of the month, the temperature usually reaches around 30 °C (86 °F).
Precipitation amounts to only 9 mm (0.4 in), distributed over 2 days.
The day lasts on average 10 hours and 55 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 44%.
The average wind speed is 16 kph (10 mph).

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September is generally a very mild month. However, there are remarkable differences between night and day. The average temperature is of 15.8 °C (60 °F), with a minimum of 9.1 °C (48.4 °F) and a maximum of 22.4 °C (72.3 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 1 °C (33.5 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 31.5 °C (89 °F).
Precipitation amounts to 22 mm (0.9 in), distributed over 3 days.
The day lasts on average 11 hours and 55 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 68% of the time.
The average humidity is 42%.
The average wind speed is 17 kph (11 mph).

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October is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of 19.0 °C (66 °F), with a minimum of 12.5 °C (54.5 °F) and a maximum of 25.6 °C (78.1 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 4.5 °C (40 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 34 °C (93.5 °F).
Precipitation amounts to 50 mm (2 in), distributed over 5 days.
The day lasts on average 12 hours and 55 minutes.
There are on average 9 hours of sunshine per day. So, the sun shines 70% of the time.
The average humidity is 46%.
The average wind speed is 19 kph (12 mph).

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November is generally a warm month. However, there are remarkable differences between night and day. The average temperature is of 21.8 °C (71 °F), with a minimum of 15.1 °C (59.2 °F) and a maximum of 28.5 °C (83.3 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 7 °C (44.5 °F).
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 35 °C (95.5 °F).
Precipitation amounts to 87 mm (3.4 in), distributed over 7 days.
The day lasts on average 13 hours and 55 minutes.
There are on average 10.5 hours of sunshine per day. So, the sun shines 75% of the time.
The average humidity is 46%.
The average wind speed is 19 kph (12 mph).

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December is generally a warm to hot month. However, there are remarkable differences between night and day. The average temperature is of 24.0 °C (75 °F), with a minimum of 17.3 °C (63.1 °F) and a maximum of 30.8 °C (87.4 °F).
On the coldest nights of the month, the temperature usually drops to around 11 °C (51.5 °F).
On the warmest days of the month, the temperature usually reaches around 37 °C (98.5 °F).
Precipitation amounts to 105 mm (4.1 in), distributed over 8 days.
The day lasts on average 14 hours and 20 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 11 hours of sunshine per day. So, the sun shines 77% of the time.
The average humidity is 47%.
The average wind speed is 18 kph (11 mph).