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September 10, 2015

Early Season Rains falling in Southern and Central Brazil

One frontal system has already triggered widespread rains across southern and central Brazil and another cold front is forecasted to sweep into southern Brazil over the next few days. The first front brought very beneficial rains to the states of Sao Paulo, Minas Gerais, Goias, Mato Grosso do Sul, and southern Mato Grosso.

The soil moisture in this region had declined significantly after several months of dry weather. This is good news for farmers who will start planting their 2015/16 soybean crop next week when the soybean-free period expires. Meteorologists are also forecasting the possibility of additional rainfall in Mato Grosso and Goias for the remainder of this week and for all of next week as well. If the forecast verifies, it could result in a quick start to soybean planting. Farmers in the region generally wait to plant their soybeans until they have received at least two inches of precipitation in order to insure adequate moisture for germination and stand establishment.

While the rain is beneficial for the planting of the summer crops, it could disrupt the ongoing sugarcane harvest in Sao Paulo and Minas Gerais.

The next cold front is expected to sweep into southern Brazil over the next few days and bring with it a significant drop in temperatures. The temperatures in Rio Grande do Sul could drop to below freezing on Friday and Saturday morning. Freezing temperatures could pose a problem for the wheat crop in the state which is 35% flowering and for the full-season corn crop which is 4% planted. A light frost probably would not be a significant problem, but a hard freeze could result in significant damage to the wheat crop.

The heavy rains have certainly been beneficial for the reservoirs that supply water to the city of Sao Paulo. After the rains on Tuesday and Wednesday, the volume of water in the Sistema Cantareira increased for the first time in 44 days. This is the main reservoir supplying water to the city of Sao Paulo and it is now at 15.4% of capacity, which is up from 15.0%. This is the first increase since July 27th.

The region received 48 mm of rainfall on Tuesday and Wednesday (1.9 inches) or 56% of the normal rainfall for all of September. Thus far in September, they have received 65 mm (2.6 inches) or 75% of their normal monthly rainfall. These rains are very welcome news for the residents of the city who were facing the possibility of water and electrical shortages due to low water levels in reservoirs that supply water and electricity.