Thunderstorm days climatology of Brazil:1961 through 1970

The thunderstorm days have been collected since 1940 in Brazil. About of 70 observation points in meteorological stations are covering all the country. These meteorological stations have hourly record about of number time that the lightning flashes were saw or the number time that thunders were heard in one day. Although the thunderstorm days are not a precise parameter it is a good indicator of lightning activity when there are not systems for lightning detection in the region. About 21 observation points were selected for the period 1961 through 1970. Maps of annual mean distribution, monthly mean distribution and local time distribution were analyzed. These maps represent a 10-year climatology of geographic distribution of lightning activity in Brazil. The potential temperature was analyzed in the same region. The possible relationship between potential temperature and distribution lightning flashes have been investigated.