São Paulo Registers Record Rainfall in 24 Hours for the Month of July

SÃO PAULO, BRAZIL – The slow displacement of a cold front over the state of São Paulo caused moderate to heavy rainfall for several hours, particularly in the central-eastern and northeastern parts of the state, the area in which the state capital is located.

The converging hot and humid northwestern winds and cold southern air intensified the instability over the capital.

According to information from the National Institute of Meteorology (INMET) at the weather station of Mirante de Santana, the cumulative rainfall of 24 hours measured between 9 AM Thursday, July 4th, and 9 AM this Friday, July 5th was 123.6 mm, an absolute record of the entire historical data for the month of July in 76 years of observation.

The most substantial previous volume had been verified on July 3rd, 1976, with 70.8 mm.

Between Wednesday and Thursday, 22.4 mm of rain was recorded, and thecumulative total was 146 mm, after 28 days without rain.

According to INMET, the historical average for July (1943-2018) is 43 mm, that is, it has rained more than three times the average of the month.

Considering the absolute rainfall data in every month, the 123.6 mm rainfall recorded in 24 hours was the fourth largest in the historical data series, losing only to December 21st, 1988 with 151.8 mm; 140.4 mm on May 25th, 2005 and 127.4 mm on January 12th, 1949.

The terms of rain, in addition to being continuous it was quite consistent in the capital. The Inmet automatic station, located on Sesc-Interlagos, the southern zone of the capital, has recorded a total of 132.2 mm since the start of the rainfall event that began on Thursday morning, July 4th.

The forecast is for the rain to stop on Saturday, as a strong polar air mass will make the weather cooler and drier over the state.

In the capital, the minimum temperature forecast for this weekend is approximately 5ºC. A cold wave alert is in effect until Monday, July 8th.

On Tuesday, July 9th, a state holiday, São Paulo should register a minimum of 7ºC and a maximum of 18ºC, with no forecast of rainfall.