Rio Grande Weather in May

May in Rio Grande averages 29°C (84°F) during the day and 24°C (75°F) at night. Quite a bit of rainfall is typical this month, with around 133 mm (5.2 in) on average. An umbrella is a good idea.

Rainfall in Rio Grande in May

You can expect rain on around 16 days based on historical patterns, with 133 mm (5.2 in) average for the month. Wet weather is a regular and significant part of this month. Frequent days of rain combined with high totals means proper waterproofs are worth packing.

Temperature in Rio Grande in May

May in Rio Grande brings high temperatures, with highs of 29°C (84°F) and nights around 24°C (75°F). This kind of day-to-night contrast is typical for this time of year. Nights stay warm at around 24°C (75°F), so light bedding and good ventilation are worth thinking about.

Sunshine in Rio Grande in May

There are approximately 255 hours of sunshine this month, resulting in mostly clear days.

Wind Speed in Rio Grande in May

Wind speeds average 3 m/s (6 knots) during May. At this speed, light breezes keep leaves and small twigs in gentle motion while the wind also provides natural cooling. Since this is an average, some days are more tranquil while others have more persistent light winds that are more noticeable.

Average water temperature in May

The water temperature is 27°C (81°F), which most people find very comfortable. A good month for swimming and water sports.

If you prefer enjoying temperate temperatures and rain-free days, January, February, March, April and December typically offer the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.

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• January
• February
• March
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• May
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For a detailed overview over the year and the best time to visit Puerto Rico, check out our Rio Grande's climate page.

Rio Grande Temperature in May

Min Temperature 24°C (75°F)  

Max Temperature 29°C (84°F)  

Water Temperature 27°C (81°F) *  

Chance of Rain 53%  

Precipitation 133 mm (5.2 in)  

Rainy days 16 days  

Humidity 75% *  

Windspeed 3 m/s (6 knots) *  

Sunshine 255 hours *  

Percentage Sunshine 63% *  

* Data from: San Juan, Puerto Rico (18 KM, 11 Miles).

Daily Historical Temperatures

50-year average (1976-2025)

Based on our historical records, temperatures in Rio Grande typically stay consistent throughout May, with daily highs averaging around 29°C (84°F). Nights are warm, with lows around 25°C (77°F).

Average temperatures in May

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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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Daily Historical Precipitation

50-year average (1976-2025)

Average daily rainfall for each day of the month based on long-term records.

Average precipitation in May

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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

‹ January February March April May June July August September October November December ›

Historical weather for Rio Grande in May

Browse day-by-day weather records for Rio Grande spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.

Historical weather Temperatures Precipitation

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‹ January February March April May June July August September October November December ›

Rio Grande historical weather extremes in May

Based on weather observations in Rio Grande between 1976 and 2026, these are the recorded extremes during May.

• On May 21, 2005, temperatures climbed to 35°C (95°F), marking the warmest May day on record.
• On May 23, 2004, Rio Grande saw its coldest May day with temperatures maxing out at 24°C (75°F).
• The coldest night in May in Rio Grande was on May 10, 1986, with a minimum of 21°C (70°F).

What to Wear in Rio Grande in May

Warm weather calls for comfortable, breathable clothing in May. Cotton t-shirts, shorts, light dresses, and sandals are perfect. You might still want a light layer for evenings or air-conditioned places (for example buses). High rain levels are expected, so pack waterproof gear and an umbrella or poncho. With water temperatures around 27°C (81°F), swimming conditions are excellent. Pack your swimsuit, goggles, and maybe some water shoes. You'll definitely want to pack sunglasses and sunscreen. There will be plenty of bright sunshine this month.

What To Do in Rio Grande in May

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

9/10

Cycling

7/10

Walking

7/10

Camping

6/10

Outdoor sports

7/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Puerto Rico, check out our Rio Grande's climate page.

More climate data for Rio Grande

Temperature Rainfall Sunshine Humidity Wind Speed Water Temp

See the full Rio Grande climate overview or explore weather in Puerto Rico.