The weather system is called an East coast low . It is formed from low-pressure over the Tasman Sea . They draw strong , moisture-laden winds across the coast , which cause heavy rain to fall . They are particularly common in the 90s and can dump hundreds of millimetres of rain . They usually move away after 12 hours but this one is going to stick around for 24-36 hours . East Coast Lows were common in the 1970s but became less common in June . 'Close to the coast winds are up to 135kmh and rain up to 200mm , ' weatherman Don White says . Police and NSW Fire and Rescue have been called in to help the SES on 2800 weather related call-outs .
The weather system is called an East coast low . It is formed from low-pressure over the Tasman Sea . They draw strong , moisture-laden winds across the coast , which cause heavy rain to fall . They are particularly common in June and can dump hundreds of millimetres of rain . They usually move away after 12 hours but this one is going to stick around for 24-36 hours . East Coast Lows were common in the 1970s but became less common in the 90s . 'Close to the coast winds are up to 135kmh and rain up to 200mm , ' weatherman Don White says . Police and NSW Fire and Rescue have been called in to help the SES on 2800 weather related call-outs .