San Luis climate

Name: San Luis
Address: AR

San Luis is warmest in January, with average highs of 30 °C, and coldest in July, when nights average 5.1 °C. January is the wettest month (103 mm) and June the driest (8.7 mm). Figures are 1991–2020 climate normals.

Across a full year San Luis averages 667 mm of rain, 152 days above 25 °C and 5 days below freezing.

Argentina · population 169,947 · 1991–2020 normals

Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month

Warmest month January 30 °C
Coldest month July 5.1 °C
Driest month June 9 mm
Wettest month January 103 mm
Least cloud August 33 % cloud
Hottest on record December 41 °C
Coldest on record July -11 °C

What to expectSan Luis through the year

San Luis has a clear annual cycle: average daily highs run from 16 °C in July to 30 °C in January, a swing of 15 °C in mean temperature across the year.

Counted across a normal year, 152 days a year reach 25 °C, 57 of them reach 30 °C, 5 nights drop below freezing. The warmest reading in the 1991–2020 record is 41 °C, in December.

Rain is strongly seasonal. January averages 103 mm against 9 mm in June — 12 times as much. Planning around the dry months matters more here than planning around temperature.

Month by month

Month	Avg high	Rainfall	Cloud
January	29.8 °C	103 mm	39 %
February	28.4 °C	84 mm	37 %
March	26.1 °C	83 mm	38 %
April	21.9 °C	53 mm	40 %
May	18.6 °C	25 mm	48 %
June	16.4 °C	9 mm	40 %
July	16.0 °C	9 mm	36 %
August	19.1 °C	15 mm	33 %
September	21.5 °C	30 mm	36 %
October	24.1 °C	66 mm	39 %
November	26.7 °C	92 mm	37 %
December	29.0 °C	99 mm	37 %

Temperature month by month

Month	Avg high	Avg low	Mean	Record high	Record low	Days above 25 °C	Days above 30 °C	Days below 0 °C
January	29.8 °C	19.4 °C	24.3 °C	40.7 °C	9.1 °C	28	15	0
February	28.4 °C	18.3 °C	22.9 °C	38.7 °C	7.3 °C	23	10	0
March	26.1 °C	16.5 °C	20.8 °C	35.6 °C	4.4 °C	19	5	0
April	21.9 °C	12.7 °C	16.7 °C	32.6 °C	0.3 °C	8	1	0
May	18.6 °C	9.3 °C	13.3 °C	31.6 °C	-4.5 °C	2	0	0
June	16.4 °C	6.3 °C	10.6 °C	29.2 °C	-3.6 °C	0	0	1
July	16.0 °C	5.1 °C	9.8 °C	30.7 °C	-11.2 °C	1	0	2
August	19.1 °C	7.2 °C	12.5 °C	34.7 °C	-4.2 °C	4	1	1
September	21.5 °C	9.6 °C	15.1 °C	37.1 °C	-8.2 °C	8	1	0
October	24.1 °C	12.8 °C	18.0 °C	39.1 °C	2.5 °C	14	4	0
November	26.7 °C	15.7 °C	20.9 °C	37.6 °C	3.2 °C	19	8	0
December	29.0 °C	18.1 °C	23.3 °C	40.9 °C	7.3 °C	26	13	0

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind
January	103 mm	13	14 h/day	39 %	56 %	19 km/h
February	84 mm	11	13 h/day	37 %	59 %	18 km/h
March	83 mm	10	12 h/day	38 %	63 %	17 km/h
April	53 mm	7	11 h/day	40 %	66 %	17 km/h
May	25 mm	4	10 h/day	48 %	67 %	16 km/h
June	9 mm	2	10.0 h/day	40 %	63 %	16 km/h
July	9 mm	2	10 h/day	36 %	56 %	17 km/h
August	15 mm	2	11 h/day	33 %	49 %	19 km/h
September	30 mm	4	12 h/day	36 %	48 %	20 km/h
October	66 mm	8	13 h/day	39 %	53 %	21 km/h
November	92 mm	12	14 h/day	37 %	52 %	21 km/h
December	99 mm	12	14 h/day	37 %	53 %	20 km/h

How San Luis compares

The same four figures for nearby destinations, so the numbers above have something to be read against. Summer high is the warmest month's average high; winter low is the coldest month's average low.

Destination	Summer high	Winter low	Rain per year	Days above 25 °C
San Luis	30 °C	5.1 °C	667 mm	152
Río Cuarto · Argentina	29 °C	4.9 °C	737 mm	136
Córdoba · Argentina	29 °C	5.0 °C	888 mm	145
Peñalolén · Chile	27 °C	1.7 °C	664 mm	101
Puente Alto · Chile	28 °C	1.4 °C	680 mm	112
Santiago · Chile	28 °C	2.7 °C	488 mm	123
Quilicura · Chile	29 °C	3.8 °C	612 mm	131

Where San Luis ranks

Ranking	Position	Value
Places with the best weather in South America in April	7th of 50	94/100
Places with the best weather in South America in September	9th of 50	94/100
Places with the best weather in South America in October	23rd of 50	90/100
Places with the best weather in South America year-round	31st of 50	83/100
The coolest places in South America in July	34th of 50	16 °C
The coolest places in South America in June	37th of 50	16 °C

Planning a trip? See the best time to visit San Luis.

QuestionsCommon questions about San Luis’s climate

When is the best time to visit San Luis?

That depends on what you want, so the honest answer is a comparison rather than a single month. March, October, November sit closest to 20 °C on average, January is the warmest month and June the driest. The month-by-month table above has the full picture.

How hot does San Luis get?

In January, the warmest month, daily highs average 30 °C. About 57 days a year pass 30 °C. The highest value in the 1991–2020 record is 41 °C.

How cold does it get in winter?

Nights average 5.1 °C in July, the coldest month. A normal year has 5 nights below freezing.

Which month is wettest in San Luis?

January, averaging 103 mm over 13 days with rain. The driest month is June with 9 mm. The year as a whole averages 667 mm.

Are these figures a forecast?

No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in San Luis rather than what any particular week will bring. Individual years can differ substantially from the normal.

Data sources and method

ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
Open-Meteo — Open-Meteo.com. CC BY 4.0
NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
GeoNames — GeoNames.org. CC BY 4.0

Normal period: 1991–2020
Data point: -33.291°, -66.325° (the coordinates the reanalysis values are taken for)
Dataset version: era5-1991-2020-scores1.1
Last processed: 1 August 2026

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.