Piauí cities record extreme heat and temperature swings

Several cities in the Brazilian state of Piauí recorded extreme temperature fluctuations and intense heat due to a mass of hot, dry air. On September 14, Castelo do Piauí, Oeiras, and Piripiri were among the hottest cities in Brazil, with temperatures exceeding 40°C. Castelo do Piauí reached 40.3°C, while Oeiras and Piripiri both recorded 40.2°C.

In the municipality of Oeiras, the temperature swing was particularly notable, recording a high of 40.7°C during the afternoon and dropping to a low of 15.6°C in the early hours of the following morning. This pattern of high daytime heat and intense nighttime cooling is attributed to dry air and minimal cloud formation, which allows for increased solar radiation.

Humidity levels across the region have dropped significantly, with some areas recording indices as low as 12%. Forecasts suggest that clear skies and low humidity will persist, with temperatures in regions such as the Center-North, Southeast, and Southwest of the state potentially reaching between 40°C and 41°C in the coming days.