San Mateo Weather in August
August in San Mateo brings high temperatures, with highs of 28°C (82°F) and nights dropping to 22°C (72°F). The rainy season is in full swing this month, so frequent downpours are part of the picture.
Rainfall in San Mateo in August
San Mateo is in the rainy season in August, with rain on around 22 days and an average of 498 mm (20 in). Rain during the rainy season here tends to be intense rather than just persistent drizzle. Expect significant downpours, often in the late afternoon.
Temperature in San Mateo in August
San Mateo in August gets highs of 28°C (82°F) during the day and drops to 22°C (72°F) at night. This kind of day-to-night contrast is typical for this time of year. Nights are mild at around 22°C (72°F), which is comfortable for most people.
Sunshine in San Mateo in August
The month brings about 171 hours of sunlight, offering a comfortable mix of sun and rainy moments.August in San Mateo has its charm, but if you're looking for destinations with pleasant temperatures and sunny skies, our weather planner can help you explore other options in the world.
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 August
Min Temperature
22°C (72°F)
Max Temperature
28°C (82°F)
Chance of Rain
73%
Precipitation
498 mm (20 in)
Rainy days
22 days
Sunshine
171 hours *
Percentage Sunshine
*
Daily Historical Temperatures
43-year average (1976-2025)
Based on our historical records, temperatures in San Mateo typically stay consistent throughout August, with daily highs averaging around 28°C (82°F). Nights are pleasant, with lows around 19°C (66°F).
Average temperatures in August
Daily Historical Precipitation
43-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in August
Historical weather for San Mateo in August
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 August
Based on 29 years of weather observations (1996-2025), these are the most extreme conditions recorded in San Mateo.
- On August 25, 1997, temperatures climbed to 33°C (91°F), marking the warmest August day on record.
- The coldest August day was on August 26, 2020, with a maximum of 22°C (72°F).
- The coldest night in August in San Mateo was on August 2, 2018, with a minimum of 14°C (57°F).
- The wettest day in August San Mateo was on August 18, 2009 with 273 mm (11 in) of precipitation.
Best Places in Costa Rica in August
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 August →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in San Mateo in August
Warm but pleasant conditions in San Mateo in August. Focus on lightweight, maybe with natural fabrics, cotton blend shirts, comfortable shorts, and breathable footwear. A light cover-up for sun protection is smart too. It's going to pour! Pack a good poncho and prepare for very wet conditions. It won't hurt to bring your sunglasses along, as you'll see some sunny periods.What To Do in San Mateo in August
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.
