The climate in Brazil

Brazil has different climates due to its size, geographic location and terrain. The equator runs through northern Brazil, resulting in a tropical climate in most parts of the country.

In the Amazon rainforest region, the climate is tropical, humid and hot throughout the year, with heavy and persistent rainfall from November to April. Temperatures are usually between 25 and 32 degrees Celsius. The Amazon rainforest is known for its abundant rainfall, due to the humid air that rises from the treetops and rivers.

Northeastern Brazil, near the Atlantic coast, has a semi-arid climate with low rainfall and high temperatures. The region is subject to droughts, and annual rainfall can vary greatly from year to year. Temperatures can reach 40 degrees Celsius in the summer months, which is challenging for agriculture and livestock.

The central-western region is known for its tropical savanna climate with distinct dry and rainy seasons. The dry season lasts from May to September, and temperatures range from 18 to 32 degrees Celsius. The rainy season lasts from October to April, but temperatures are only slightly higher then.

The south has a humid subtropical climate with mild temperatures and rainfall year-round. Winters are rarely cold here, but in the highlands there are occasional snowfalls and temperatures below freezing. Summers are pleasantly warm at 20-28 degrees, but also humid.

The Atlantic coastal regions also have a tropical climate with high humidity and year-round precipitation. On the northeast coast, seasonal winds known as trade winds prevail, bringing rain and cooler temperatures from June to August. On the south coast, the warm Brazil Current of the Atlantic Ocean brings rain and storms during the summer months.

Temperature records of the last 74 years

The hottest temperature measured from 1949 to January 2023 was reported by the Poxoreo weather station. In October 2020, the record temperature of 44.5 °C was reported here. The hottest summer from July to September, based on all 163 weather stations in Brazil below 1,160 meters altitude, was recorded in 2020 with an average temperature of 24.6 °C. This average temperature will normally be measured every four to six hours, thus also including the nights. Normally, this value is 23.4 degrees Celsius. The average maximum daily temperature at that time was 30.4 °C.

The coldest day in these 74 years was reported by the Irati weather station. Here the temperature dropped to -3.9 °C in July 2019. Irati lies at an altitude of 882 meters above sea level. The coldest winter (January to March) was in 1965 with an average temperature of 24.3 °C. In Brazil, it is usual to have about 1.2 degrees more at 25.5 °C for this three-month period.

The most precipitation fell in September 2013. With 333.3 mm per day, the Vilhena weather station recorded the highest monthly average of the last 74 years. Incidentally, the region with the most rainfall for the whole year is around Belem. The driest region is near Petrolina.

Long-term development of temperatures from 2001 - 2022

In contrast to single record values, long-term development cannot simply be brought about by all weather stations in the country. Both the number and the locations are constantly changing. An average value would give a distorted result. If several measuring stations in particularly cold mountain or coastal regions are added in one year, the average would decrease as a result of this alone. If a station fails during the summer or winter months, it does not provide any values and distorts the average again. The subsequent long-term development was therefore reduced to only 3 measuring points in order to have comparable data over as long a period as possible.

In the years 2001 to 2022, there were only these 3 weather stations in the whole country, which reported continuous temperature values (Caratinga, Irati, Posse). From these weather reports, we have created a long-term development that shows the monthly average temperatures. The hottest month in this entire period was January 2019 at 24.7 °C. July 2021 was the coldest month with an average temperature of 16.8 °C.

The average annual temperature was about 21.3 °C in the years after 2001 and about 21.4 °C in the last years before 2022. So it has hardly changed at all in the past 22 years. This trend only applies to the selected 3 weather stations in Brazil. A considerably more comprehensive evaluation of global warming has been provided separately.

Data basis and methodology

The data from the individual measuring stations are based on the archives of the German Weather Service, individual values averaged and supplemented by own elements. In order to determine a representative national average, average values were first calculated for each part of the country, which were then summarized at the national level. Thus, if a disproportionate number of weather stations are located in a small area, their number does not affect the national average. There are 164 stations in Brazil itself. In 30 cases, neighboring but nearby weather stations were also used to obtain more accurate values.