Inmet: weather forecast between January 5th and 12th, 2026

The National Institute of Meteorology (Inmet) released today (January 5th) the weather forecast until January 12th, 2026. According to bulletin nº 01/2026, the presence of the South Atlantic Convergence Zone (ZCAS), the approach of transient systems in the South, and the convergence of humidity in the Southeast should favor the occurrence of large accumulations of rain, exceeding 150 mm during the week. Furthermore, storms are expected in São Paulo (SP) and Rio Grande do Sul (RS).

According to the institute, the Intertropical Convergence Zone (ITCZ) will favor rainfall in Amapá (AP), while the presence of an Upper-Level Cyclonic Vortex (VCAN) will prevent rainfall in much of eastern Northeast Brazil in the coming days. 

Na Northern RegionThe highest rainfall volumes are expected to be concentrated in Amapá, Acre, Amazonas, Rondônia, southern Pará, and Tocantins, with accumulations between 80-150 mm over seven days. In other areas, low rainfall volumes are forecast, with accumulations below 50 mm over seven days. Minimum relative humidity, in general, will remain high (equal to or greater than 70%), except in northern Pará, southern Amapá, and Roraima, where it may reach minimums around 35% throughout the week.

For North East Region The forecast is for showers, accompanied by thunderstorms, in Maranhão, south-central Piauí, west and south of Bahia. On the coast, conditions will be mostly stable throughout the week, with minimum humidity above 45%. From Thursday (08), except for southern Maranhão, the forecast is for stable weather throughout the Northeast.

Na Midwest regionHeavy rainfall is expected between Goiás and Mato Grosso, where accumulated volumes may exceed 150 mm. From Friday (09), the rain will be concentrated between the states of Mato Grosso and Mato Grosso do Sul. In the Federal District, the forecast is for accumulations below 50 mm. It is also worth noting the forecast of minimum relative humidity below 30% in western Mato Grosso do Sul throughout the week.

For SoutheastThe forecast indicates intense rainfall until the first half of the week due to the ZCAS action. From Tuesday (06), accumulations of around 50 mm are expected in 24 hours on the coast of Rio de Janeiro. For São Paulo, accumulations of around 50 mm in 24 hours are expected on the coast. Inland, storms are also expected. At the weekend, the forecast is for fair weather in most of the region, except for the south and west of SP.

For SouthThe start of the week will be marked by stable weather and cold mornings. With the approach of frontal systems on Wednesday (07), storms are expected in Rio Grande do Sul. In the following days, storms are expected for the other states in the Region. The highest accumulated rainfall is expected to be up to 150 mm. The lowest relative humidity values ​​should initially be around 40% in all states until Wednesday (07), and in the following days the values ​​should be above 50%.