Costa Rica Weather in May

NASA POWER reanalysis for the half-degree grid cell around Costa Rica, 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 May 1 to 34°C on May 31, and lows from 21°C to 24°C. Normal precipitation for the month is 0 mm over about 0 wet days.

May day by day

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

Normal low
Normal high
Reanalysis extreme high
Reanalysis extreme low

May at a glance

Average high: 33°C
Average low: 22°C
Precipitation: 0 mm
Reanalysis high: 38°CMay 4, 2002
Reanalysis low: 17°CMay 1, 1999
Daylight: 13 h 05 min to 13 h 33 min
Cloud cover: 23%
Humidity: 54%
Dew point: 16°C
Wind: 11.5 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
May 1	32°C	21°C	34°C 2019	17°C 1999	0%
May 2	32°C	21°C	35°C 1996	17°C 1999	0%
May 3	32°C	21°C	36°C 2002	18°C 2010	0%
May 4	33°C	21°C	38°C 2002	18°C 1999	0%
May 5	33°C	21°C	35°C 2012	19°C 1999	0%
May 6	33°C	21°C	35°C 2002	19°C 2001	0%
May 7	33°C	21°C	36°C 2002	19°C 2001	0%
May 8	33°C	21°C	35°C 2011	18°C 1995	0%
May 9	33°C	21°C	35°C 2011	18°C 1995	0%
May 10	33°C	22°C	35°C 2002	19°C 1995	0%
May 11	33°C	22°C	35°C 2008	20°C 1998	0%
May 12	33°C	22°C	36°C 2008	20°C 2011	0%
May 13	33°C	22°C	35°C 2006	19°C 2011	0%
May 14	33°C	22°C	37°C 2014	19°C 2019	0%
May 15	33°C	22°C	35°C 2000	19°C 1993	1%
May 16	33°C	22°C	36°C 1998	19°C 1993	0%
May 17	33°C	22°C	37°C 2014	20°C 2017	0%
May 18	33°C	22°C	36°C 1994	18°C 1995	0%
May 19	33°C	22°C	37°C 1994	20°C 1991	0%
May 20	33°C	22°C	37°C 1997	20°C 1991	0%
May 21	33°C	23°C	36°C 2006	20°C 2007	0%
May 22	33°C	23°C	36°C 2006	20°C 2007	0%
May 23	34°C	23°C	37°C 2014	20°C 2007	0%
May 24	34°C	23°C	36°C 2018	20°C 2008	0%
May 25	34°C	23°C	36°C 2002	20°C 2008	1%
May 26	34°C	23°C	37°C 2007	21°C 1998	1%
May 27	34°C	23°C	38°C 1999	21°C 2008	1%
May 28	34°C	23°C	36°C 1998	22°C 1994	1%
May 29	34°C	23°C	36°C 2015	22°C 1991	1%
May 30	34°C	24°C	37°C 2007	21°C 1992	1%
May 31	34°C	24°C	37°C 1998	21°C 1991	2%

Chance of rain

Chance of a wet day

Sunrise and sunset

Times for 2026, local time (GMT-7).

May 1: sunrise 5:34 AM, sunset 6:39 PM
May 31: sunrise 5:21 AM, sunset 6:54 PM

Every day of May: 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.