Study of wind gust and its predominant directions in Lavras, Minas Gerais, Brazil, through gamma distribution

The present work was carried out in order to study the ccurrence probabilities o of extreme winds and their predominant directions in the region of Lavras, Minas Gerais state, Brazil. The data were collected from graphic registrations of the universal anemograph of the Principal Climatological Station of Lavras, located in the campus of the Federal University of Lavras. With the available data (139 months), in the period of January/1988 to May/2004, the adjustment by Gamma distribution was verified for this data series applying the chi(2) test to the 5% probability. Estimates of the occurrence probabilities of wind gust equal or above 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100 km h(-1) were determined for each month. It was verified that the months of September to February presented strong winds with probabilities higher than the other months. For very strong winds, above 100 km h(-1), the occurrence probabilities were minimum for all months of the year. It was observed that the predominant wind gust direction were east and west in relation to the others.