Juan José Castelli Weather in December

NASA POWER reanalysis for the half-degree grid cell around Juan José Castelli, 1991-2020; a grid cell is an area average and can differ from a thermometer in town by several degrees

Average highs run from 34°C on December 1 to 36°C on December 31, and lows from 21°C to 23°C. Normal precipitation for the month is 146 mm over about 12 wet days.

December day by day

The normal high and low for each date, in °C.

Normal low
Normal high
Reanalysis extreme high
Reanalysis extreme low

December at a glance

Average high: 35°C
Average low: 22°C
Precipitation: 146 mm
Reanalysis high: 44°CDec 16, 2017
Reanalysis low: 11°CDec 1, 2001
Daylight: 13 h 39 min to 13 h 45 min
Cloud cover: 60%
Humidity: 60%
Dew point: 18°C
Wind: 14.0 km/h

Every day of the month

A wet day has at least 1 mm of precipitation in the reanalysis.

Date	Normal high	Normal low	Reanalysis high	Reanalysis low	Chance wet
Dec 1	34°C	21°C	43°C 2007	11°C 2001	42%
Dec 2	34°C	21°C	40°C 2004	15°C 2001	42%
Dec 3	34°C	21°C	42°C 2012	13°C 2008	42%
Dec 4	34°C	21°C	40°C 1998	13°C 2008	41%
Dec 5	34°C	21°C	38°C 2012	13°C 2000	41%
Dec 6	34°C	21°C	40°C 2012	13°C 1999	39%
Dec 7	34°C	21°C	42°C 2014	16°C 2005	39%
Dec 8	34°C	21°C	41°C 2017	17°C 2018	38%
Dec 9	34°C	21°C	39°C 2014	15°C 2001	38%
Dec 10	34°C	21°C	42°C 2012	16°C 1998	37%
Dec 11	34°C	21°C	41°C 2020	17°C 2005	36%
Dec 12	35°C	21°C	42°C 2012	17°C 2007	36%
Dec 13	35°C	22°C	41°C 1994	14°C 2010	37%
Dec 14	35°C	22°C	42°C 2018	12°C 2010	38%
Dec 15	35°C	22°C	42°C 2017	13°C 2016	37%
Dec 16	35°C	22°C	44°C 2017	14°C 2016	38%
Dec 17	35°C	22°C	42°C 2012	13°C 2000	37%
Dec 18	35°C	22°C	42°C 2010	15°C 2003	35%
Dec 19	35°C	22°C	43°C 2010	18°C 2016	36%
Dec 20	35°C	22°C	43°C 2011	18°C 2016	37%
Dec 21	36°C	22°C	43°C 2008	17°C 2020	38%
Dec 22	36°C	22°C	44°C 2011	17°C 1998	38%
Dec 23	36°C	23°C	41°C 2007	15°C 1998	39%
Dec 24	36°C	23°C	41°C 2013	15°C 1998	41%
Dec 25	36°C	23°C	42°C 2013	16°C 2002	42%
Dec 26	36°C	23°C	41°C 2013	17°C 2004	43%
Dec 27	36°C	23°C	42°C 2002	16°C 1991	43%
Dec 28	36°C	23°C	42°C 2002	16°C 2012	41%
Dec 29	36°C	23°C	41°C 1997	17°C 2003	41%
Dec 30	36°C	23°C	41°C 1997	15°C 1993	41%
Dec 31	36°C	23°C	41°C 1994	16°C 1993	41%

Chance of rain

Chance of a wet day

Sunrise and sunset

Times for 2026, local time (GMT-3).

December 1: sunrise 6:02 AM, sunset 7:41 PM
December 31: sunrise 6:13 AM, sunset 7:58 PM

Every day of December: sun and moon

Other months

Sources

Cloud, humidity, wind and sunshine, and temperature and precipitation: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus.