Mercedes Weather in December

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

Average highs run from 29°C on December 1 to 32°C on December 31, and lows from 15°C to 18°C. Normal precipitation for the month is 130 mm over about 12 wet days.

December day by day

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

Normal low
Normal high
Record high
Record low

December at a glance

Average high: 30°C
Average low: 16°C
Precipitation: 130 mm
Record high: 42°CDec 19, 1944
Record low: 3°CDec 1, 2011
Daylight: 14 h 11 min to 14 h 19 min
Cloud cover: 48%
Humidity: 63%
Dew point: 15°C
Wind: 15.1 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	Record high	Record low	Chance wet
Dec 1	29°C	15°C	37°C 1987	3°C 2011	32%
Dec 2	29°C	15°C	36°C 1971	5°C 1943	32%
Dec 3	29°C	15°C	36°C 2004	5°C 1967	33%
Dec 4	29°C	15°C	38°C 1954	5°C 1938	32%
Dec 5	29°C	15°C	38°C 1949	3°C 1971	33%
Dec 6	29°C	15°C	37°C 1944	5°C 1939	34%
Dec 7	29°C	15°C	37°C 1954	4°C 1982	34%
Dec 8	30°C	15°C	36°C 2010	6°C 2018	34%
Dec 9	30°C	15°C	37°C 1948	8°C 2001	36%
Dec 10	30°C	15°C	38°C 1948	7°C 1938	35%
Dec 11	30°C	15°C	38°C 2020	6°C 1959	33%
Dec 12	30°C	16°C	39°C 1994	7°C 1937	34%
Dec 13	30°C	16°C	37°C 1944	6°C 1937	34%
Dec 14	30°C	16°C	39°C 1944	7°C 2020	37%
Dec 15	30°C	16°C	37°C 1931	7°C 1958	38%
Dec 16	30°C	16°C	38°C 1931	4°C 1934	39%
Dec 17	30°C	16°C	39°C 1931	7°C 1947	38%
Dec 18	30°C	16°C	40°C 1995	7°C 1964	39%
Dec 19	30°C	16°C	42°C 1944	9°C 1960	39%
Dec 20	31°C	17°C	40°C 1949	8°C 1960	38%
Dec 21	31°C	17°C	38°C 2011	7°C 1980	37%
Dec 22	31°C	17°C	37°C 2011	7°C 1965	36%
Dec 23	31°C	17°C	38°C 1962	8°C 2014	36%
Dec 24	31°C	17°C	38°C 2010	8°C 1966	35%
Dec 25	31°C	17°C	38°C 1970	9°C 1959	36%
Dec 26	31°C	17°C	38°C 1967	7°C 1933	35%
Dec 27	31°C	17°C	42°C 2013	7°C 1934	34%
Dec 28	31°C	18°C	39°C 2010	6°C 1934	35%
Dec 29	32°C	18°C	39°C 2021	7°C 1964	33%
Dec 30	32°C	18°C	41°C 1932	10°C 2023	32%
Dec 31	32°C	18°C	41°C 1942	9°C 1979	32%

Chance of rain

Chance of a wet day

Sunrise and sunset

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

December 1: sunrise 5:36 AM, sunset 7:47 PM
December 31: sunrise 5:46 AM, sunset 8:05 PM

Every day of December: sun and moon

Other months

Sources

Records: NOAA GHCN-Daily, station UY000086490, every year on file, quality-flagged values removed. 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.