For this week, the action of two humidity convergence zones influences the accumulation for all of Brazil, in addition to other systems that should occur closer to the end of the week, including the southeast region.
In image 1, see the total accumulated for the week, until next Monday, 20th.
Image 1 – Accumulated precipitation over seven days, valid for Monday, 20th.
The ITCZ influences instabilities in the extreme north of Pará, such as the capital Belém, and the entire coast and part of the interior of the states of Maranhão, Piauí, Ceará and Rio Grande do Norte.
The ZCAS, which has been in operation since last week in the south of Bahia, is issuing a warning for the central-northern region of the country due to heavy and heavy rains, with the risk of hail and lightning strikes several times. The system is likely to dissipate from Wednesday onwards.
A low pressure center in the Atlantic near Rio Grande do Sul favors large volumes of rain for the Brazilian southeast, such as São Paulo, and part of Mato Grosso do Sul, starting on Thursday afternoon.
A curious fact is that the large volumes of rain in the north and northeast regions, as mentioned in the paragraphs above, are also being influenced by the Madden-Julian Oscillation (MJO), which is currently in phase 1, as shown in image 2. This intensification of precipitation is enhanced by high temperatures in the Atlantic Ocean, as shown in image 3, which increases the humidity available in the atmosphere, resulting in more intense and frequent rains.
Image 2 – Indication of the level of the Madden Julian Oscillation.
In the northeast, especially in the western and southern areas, phase 1 of the OMJ, together with the ITCZ and moisture channels, contributes to heavy and intense rainfall.
In the North, the t action of the OMJ and ZCIT increases the potential for heavy rains and storms.
Image 3 – Temperature anomaly from February 26 to February 2, 2025. Note the anomalous increase in ocean temperature off the northeast coast.
The JMO is a climate phenomenon characterized by the eastward propagation of large areas of tropical convection, influencing precipitation patterns in several regions of the globe, such as Brazil. It has eight distinct phases, each with impacts on the Brazilian climate.
Following the opposite path, in the south of Brazil there will be practically no significant rain until the morning of the 15th. Only in Paraná should there be heavy rain from Thursday onwards, due to the entry of humidity from the Amazon.
Points of attention of the week:
- South of Bahia and north of Minas Gerais until Wednesday, due to heavy rains and the possibility of ice at altitude (route to Coroa do Avião, mainly);
- Northern Pará, especially the capital Belém, for large accumulations of rainfall;
- Coast and part of the interior of Maranhão, Piauí, Ceará and Rio Grande do Norte for large accumulations;
- Goiás between Tuesday and Thursday for large accumulations, mainly in the northwest sector, such as São Miguel do Araguaia (162mm of accumulation in the week);
- Brasília between Tuesday and Wednesday for peaks in accumulated rainfall;
- Sinop, with a forecast of 117mm accumulated for the week, with peaks occurring between Monday and next Wednesday;
- From Thursday afternoon, pay attention to the region of Londrina and the state of São Paulo, for large accumulations of rain and storms.
Continuing as a point of attention, we must monitor the entry of easterly winds into Rio Grande do Sul from Wednesday onwards, as temperatures are forecast to reach 38ºC, which facilitates the formation of major storms when moisture first enters the continent.
