San Mateo Weather in May
May in San Mateo brings high temperatures around 29°C (84°F) during the day, dropping to 22°C (72°F) at night, and as part of the rainy season, heavy rainfall is common.
Rainfall in San Mateo in May
As part of the rainy season, San Mateo sees around 17 days of rain in May, with an average of 444 mm (17 in). Showers during the rainy season tend to be heavy and can come down intensely. An umbrella is often not enough, so a poncho or waterproof jacket is a better choice.
Temperature in San Mateo in May
Temperatures in San Mateo in May top out at 29°C (84°F) and drop to 22°C (72°F) overnight. Conditions stay fairly consistent through the month, making it easier to plan what to wear. Nights are mild at around 22°C (72°F), which is comfortable for most people.
Sunshine in San Mateo in May
The city usually sees around 203 hours of sunlight, indicating many sunny days despite it being the rainy season.If you prefer dry days with pleasant temperatures, May may not be the ideal month to visit San Mateo. Our weather planner can help you explore destinations with more pleasant weather conditions.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Costa Rica, check out our San Mateo's climate page.
San Mateo Temperature in May
Min Temperature
22°C (72°F)
Max Temperature
29°C (84°F)
Chance of Rain
58%
Precipitation
444 mm (17 in)
Rainy days
17 days
Sunshine
203 hours *
Percentage Sunshine
*
Daily Historical Temperatures
43-year average (1977-2025)
Based on our historical records, temperatures in San Mateo typically stay consistent throughout May, with daily highs averaging around 29°C (84°F). Nights are pleasant, with lows around 20°C (68°F).
Average temperatures in May
Daily Historical Precipitation
43-year average (1977-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in May
Historical weather for San Mateo in May
Browse day-by-day weather records for San Mateo spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
San Mateo historical weather extremes in May
According to our 29 years of weather records for San Mateo, the following extremes were recorded between 1997 and 2026.
- The warmest day in May was on May 25, 1998, with a maximum of 34°C (93°F).
- The coldest May day was on May 29, 2008, with a maximum of 19°C (66°F).
- The coldest night in May in San Mateo was on May 7, 2013, with a minimum of 16°C (61°F).
- The wettest day in May San Mateo was on May 15, 2001 with 156 mm (6.1 in) of precipitation.
Best Places in Costa Rica in May
Find out more about the weather in Costa Rica and which places have the best travel conditions in this month. See all of Costa Rica in May →
perfect weather
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tolerable
unpleasant
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What to Wear in San Mateo in May
Warm temperatures in May make for comfortable sightseeing weather. Pack breathable fabrics like cotton shirts, knee-length shorts or skirts, and comfortable walking shoes. A thin long sleeve for indoor spaces is handy. Heavy rain is guaranteed, please bring a good poncho and waterproof everything! You'll definitely want to pack sunglasses and sunscreen. There will be plenty of bright sunshine this month.What To Do in San Mateo in May
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Costa Rica, check out our San Mateo's climate page.
See the full San Mateo climate overview or explore weather in Costa Rica.
