Weather in Rio de Janeiro in May

How May compares

May is the 10th warmest month of the year in Rio de Janeiro and ranks 51st of 134 destinations we compare for May - see where else is hot in May. Against London's average high of 16.6°C in May, Rio de Janeiro is 9.0°C warmer by day and 10.8°C warmer at night.

Daytime and night-time in May

The typical May day in Rio de Janeiro peaks at 25.6°C, but that is an average: the warmest 10% of days reach 29.4°C or more. About 54% of days top 25°C and 1 in 14 pass 30°C. Nights average 19.1°C; one night in ten drops to 16.8°C or lower, so pack a layer for evenings. Between 1991 and 2020 the hottest May day here reached 33.2°C (1993-05-14) and the coldest night 14.1°C (2006-05-20).

Rain in May

Wet (more than 8 rainy days): about 11 days with 1 mm or more, 76 mm in total. Year to year it varies a lot - the wettest May was 1995 with 161 mm, the driest 2000 with 33 mm. Humidity averages 82%.

Sea temperature in May

The sea averages 23.6°C - warm enough to swim (22°c+). Depending on the year it ranges from 22.8°C to 24.3°C. For the warmest sea here, come in February (26.4°C).

Sunshine and daylight

Around 5.1 hours of sunshine a day (estimated from cloud cover), 10.9 hours of daylight: the sun rises about 06:19 and sets about 17:20 local time in mid-May. Average cloud cover is 53%.

Is May a good time to visit Rio de Janeiro?

It is a reasonable choice: hot days but expect showers. The best months for Rio de Janeiro on our scoring are August, June, July; months averaging 25°C or more: Jan, Feb, Mar, Apr, May, Jun, Aug, Sep, Oct, Nov, Dec.

Warm enough for summer clothes, with cooler evenings

Pack mainly light, breathable clothes, with a light layer for cooler evenings. Days reach 25°C about 54% of the time, but only 7% reach 30°C, so May suits travellers who want warmth without making intense heat the main feature of the trip. Humidity averages 82%, which can make walking feel sticky even when the temperature looks manageable. Take breaks around midday and leave more active plans for when you feel comfortable. Nights are generally mild, though the coldest can fall to 16.8°C or below. A long-sleeved layer is sensible if you tend to feel chilly after sitting outside for a while.

Plan for swimming, but leave room for rain

The sea is warm enough for swimming, but the weather calls for a flexible approach to beach days. Rain falls on about 11 days in May, so bring a light waterproof and have something indoors in mind when conditions turn wet. That does not mean every rainy day is a washout, but neither should you assume rain will be brief or neatly timed. Average sunshine is about 5.1 hours within 10.9 hours of daylight: there is time to be outdoors, but daylight is not the same as clear skies. May works best if you are happy to use brighter spells for swimming and change plans when necessary.