Storms are severe weather systems that can bring damaging winds, heavy rain, hail, lightning and dangerous surf. In NSW, storms range from short-lived thunderstorms to larger low-pressure systems such as east coast lows.

Thunderstorms

A thunderstorm is a weather system that produces thunder and lightning. Thunderstorms can bring heavy rain, thunder and lightning, hail, strong wind gusts and tornadoes. They are most common from September to March when the ocean is warmer.

Features of a thunderstorm

Diagram illustrating the structure and key features of a thunderstorm cloud. A cross‑section shows a tall cumulonimbus cloud extending to around 15 km, with a flat anvil-shaped top spreading outward and an “overshooting top” rising above it. Inside the cl

Past event: 8 and 9 October 2007

  • Supercell thunderstorms hit Lismore causing widespread damage, producing large hail and strong winds.
  • Estimated damage of $200 million*
  • 17 people were injured and NSW SES received around 300 requests for assistance.

*Insurance Council of Australia damage estimates in current day values

Current risk

  • The Northern Rivers experiences a high number of thunderstorms each year and has some of the most hail damage in NSW.
  • While most hailstorms cause small to moderate damage, the high frequency of hail in the region means impacts build over time.

Future risk

  • Climate projections suggest more intense short-duration heavy rainfall, even in regions where the average rainfall decreases or stays the same. However, there is still uncertainty about how this will affect thunderstorms, including large hail events.
  • More research is needed across Australia to better understand how thunderstorms may change in the future.
  • Overall, the risk from thunderstorms in the Northern Rivers is expected to increase over time due to continued population growth across the region.

Impacts

Built

  • Damage to buildings, infrastructure, vehicles and culturally significant sites from flooding, lightning, hail, strong winds, falling trees and debris

Social

  • Serious injury or loss of life from lightning or hail, falling trees, vehicle accidents, being swept away in floodwaters or landslides, building collapse, or slips and falls on wet and damaged surfaces
  • Displacement, mental stress, isolation
  • Disruption to essential services

Economic

  • Business disruption and economic losses due to service outages, closures, damage to assets
  • Reduced agricultural productivity from damage to crops, livestock and machinery

Natural

  • Damage or destruction of trees, wildlife and natural habitats from strong winds, debris, flash flooding and storm surge
  • Coastal erosion
  • Ecosystem impacts


Next steps

Note: The information contained on these Have Your Say website pages is general information only, based on knowledge and understanding at the time of publication (June 2026) or otherwise based on data which pre-dates its publication, and may be subject to change at any time without notice. The State of NSW and its agencies (including the NSW Reconstruction Authority) do not give any warranty or representation as to the accuracy, reliability or completeness of the information. Read our full legal notice at bottom of the Have Your Say landing page.