Average annual thunder-day and lightning flash density
These maps show the average annual number of thunder-days using data over a ten year period (1990-1999), and lightning total flash density (Nt) and lightning ground flash density (Ng) across Australia using data over an 18-year period (1995-2012).
Product code: IDCJCM0007
These maps show the annual variation in thunderstorm and lightning activity across Australia. The annual average thunder-day map is based on observed thunderstorm activity at about 300 weather stations over a ten year year period (1990-1999). The lightning maps are based on eighteen years of satellite derived data (1995-2012).
The annual thunder-day map shows thunderstorms are most frequent over the northern half of the country, and generally decrease southward, with lowest frequencies in southeast Tasmania. A secondary maximum is also apparent in southeast Queensland and over central and eastern New South Wales, extending into the north eastern Victorian highlands.
The average annual total lightning flash density (Nt) map shows the geographical distribution of both cloud-to-ground and cloud-to-cloud flashes. A high level of lightning activity is observed in the northern parts of Australia, and a decrease in total flash density occurs southward in central and southern parts of Australia. The peak lightning occurrence is in the north western part of the Australian continent. The average annual lightning ground flash density (Ng) map shows a similar geographical distribution of cloud-to-ground flashes.