THE Bureau of Meteorology has issued a severe thunderstorm warning for parts of NSW.
Cessnock is among the locations which may be affected by damaging winds, and heavy rainfall that may lead to flash flooding and large hailstones over the next several hours.
The State Emergency Service advises that people should move cars under cover or away from trees; secure or put away loose items around your house, yard and balcony; and keep at least 8 metres away from fallen power lines or objects that may be energised, such as fences.
People are encouraged to report fallen power lines to either Ausgrid on 131 388, or Endeavour Energy on 131 003 or Essential Energy on 132 080, as shown on your power bill.
It is also advised that people keep clear of creeks and storm drains ;and not walk, ride a bike or drive through flood water.
If trapped by flash flooding, seek refuge in the highest available place and contact 000 if you need to be rescued.
Unplug computers and appliances, and avoid using the phone during the storm.
Finally, it is important to stay indoors away from windows, and keep children and pets indoors as well.
For emergency help in floods and storms, contact the SES on 132 500.