São Luís Weather in December

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

Average highs run from 32°C on December 1 to 31°C on December 31, and lows from 26°C to 25°C. Normal precipitation for the month is 56 mm over about 9 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: 31°C
Average low: 26°C
Precipitation: 56 mm
Reanalysis high: 34°CDec 30, 2002
Reanalysis low: 23°CDec 17, 2016
Daylight: 12 h 15 min to 12 h 16 min
Cloud cover: 58%
Humidity: 75%
Dew point: 23°C
Wind: 10.4 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	32°C	26°C	34°C 2015	24°C 1993	13%
Dec 2	32°C	26°C	34°C 2015	25°C 2006	14%
Dec 3	32°C	26°C	33°C 1997	25°C 2001	14%
Dec 4	32°C	26°C	33°C 2017	24°C 2001	14%
Dec 5	32°C	26°C	33°C 1998	24°C 2001	15%
Dec 6	32°C	26°C	33°C 1997	25°C 2018	17%
Dec 7	32°C	26°C	33°C 1999	25°C 1995	18%
Dec 8	32°C	26°C	33°C 1999	25°C 2018	19%
Dec 9	32°C	26°C	33°C 1999	24°C 1996	20%
Dec 10	32°C	26°C	33°C 1999	25°C 1995	21%
Dec 11	32°C	26°C	33°C 2016	25°C 1995	22%
Dec 12	32°C	26°C	33°C 2017	25°C 2004	24%
Dec 13	31°C	26°C	33°C 1999	25°C 1996	26%
Dec 14	31°C	26°C	33°C 2002	24°C 2010	28%
Dec 15	31°C	26°C	33°C 2002	24°C 2000	28%
Dec 16	31°C	26°C	33°C 2005	24°C 2000	30%
Dec 17	31°C	26°C	34°C 2005	23°C 2016	32%
Dec 18	31°C	26°C	33°C 2005	24°C 2010	34%
Dec 19	31°C	26°C	32°C 1997	24°C 2016	35%
Dec 20	31°C	26°C	33°C 2019	24°C 2016	35%
Dec 21	31°C	26°C	33°C 2014	24°C 2000	35%
Dec 22	31°C	26°C	33°C 2010	24°C 1999	36%
Dec 23	31°C	26°C	32°C 2008	24°C 1999	36%
Dec 24	31°C	26°C	33°C 2013	24°C 1999	37%
Dec 25	31°C	26°C	33°C 2013	24°C 2018	38%
Dec 26	31°C	26°C	34°C 2019	24°C 1994	40%
Dec 27	31°C	26°C	33°C 2015	24°C 1994	41%
Dec 28	31°C	26°C	33°C 2008	24°C 1994	42%
Dec 29	31°C	26°C	32°C 2008	24°C 1999	44%
Dec 30	31°C	26°C	34°C 2002	24°C 1999	46%
Dec 31	31°C	25°C	33°C 2002	25°C 1999	48%

Chance of rain

Chance of a wet day

Sunrise and sunset

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

December 1: sunrise 5:39 AM, sunset 5:54 PM
December 31: sunrise 5:52 AM, sunset 6:08 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 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.