Parts of the NSW coast have seen their heaviest rain in four years as an East Coast Low creeps north. The low pressure system has already triggered showers along the entire length of the state's coastline, with towns between Coffs Harbour and Tarree picking up the heaviest falls so far. During the 24 hours to 9am Friday, Port Macquarie recorded 155mm, the heaviest rain since February 2009 and the heaviest for May in 12 years. Further north, Coffs Harbour saw 106mm, the heaviest during May since 2005. Parts of the Illawarra also registered triple figure totals to 9am Friday, with 111mm at Darkes forest coming in as the heaviest May rain in 15 years. Around Sydney, Turramurra collected their highest May total in a decade with 70mm, while the city picked up 31mm, the heaviest in just over a month. As the low tracks further north during Friday afternoon and evening, the heaviest rain will continue to target the stretch of coast between Lismore and Port Macquarie. Between 9am and 1:30pm, Coffs Harbour had already registered another 82mm of rain. This brings their running monthly total for May to 220mm, which is 61mm above the long term average and makes this the wettest May in 14 years. The low may also generate damaging winds north of about Port Macquarie during Friday afternoon and evening, particularly with any thunderstorm activity. Looking ahead, isolated showers will extend to about Wollongong tonight before clearing from the Illawarra early Saturday morning. By mid-morning on Saturday, there will only be showers north of about Newcastle, which will mostly clear by the evening. A high pressure system moving into the region over the weekend will bring more stable conditions. Most of the NSW coast will enjoy clear skies on Sunday, allowing built-up loads of washing to finally hang out to dry.