A MAN has been killed by lightning at a racecourse in central western NSW as storms hit the state.
Emergency services were called to Comobella Road at Guerie, near Dubbo, just after 2pm on Saturday following reports a man had been struck by lightning.
Paramedics assessed the 53-year-old but he had died at the scene.
"Unfortunately there wasn't much we could do," a NSW Ambulance spokeman told AAP.
A report will be prepared for the coroner.
The incident comes after the Bureau of Meteorology issued a warning for a severe thunderstorm that has pushed north from the ACT.
Large hailstones, damaging winds and heavy rain have been forecast for central parts of the state, including Orange, Goulburn, Dubbo, Parkes and Walgett. Heavy rain and flash flooding is also expected to lash Sydney, parts of the Hunter and the Illawarra.
The storms are set to interrupt some of the major events happening in Sydney on Saturday including the Invictus Games opening ceremony and extreme sports X Games at Homebush.
"Due to the speed, volatility and potential impacts of thunderstorms it is recommended people pay particular attention to warnings," Bureau of Meteorology spokesman Jake Phillips said earlier in a statement.
A Sydney photographer who snapped a photo of Saturday's storm before it hit the CBD.
Residents across Australia's east coast endured a severe thunderstorm, which hit parts of NSW on Saturday afternoon.
After weeks of rain the Bureau of Meteorology warned the large storm cell would bring "large hailstones, heavy rainfall that may lead to flash flooding and damaging winds".
The storms were forecast to hit the central and southern parts of the state, including Sydney, this afternoon before moving to the state's north east tomorrow.
Josh Burkinshaw, 36, saw the weekend forecast as the perfect opportunity to get his camera out.
"I could hear the rumbling thunder at home as out side started to get dark," Mr Burkinshaw said.
"I flew my drone out to capture this amazing storm front approaching the coast from over the mountains".
The result of his efforts shows a massive, dark blue storm cell, making its way up through Batemans Bay, on the South Coast of NSW.
Mr Burkinshaw said since he captured the image early today, the temperature has dropped and it "feels like winter again".
"We don't get storm to much from the mountains so to capture this from my home is pretty amazing," he said.
When the storms hit, they have no plans of letting up, with rainfall set to carry through to next week.
Communities in Orange, Canberra, Goulburn, Cooma, Yass and Tumbarumba in particular have been urged to stay indoors and prepare for power outages and flash flooding.
A severe thunderstorm warning has also been issued for residents in the Southern Tablelands, South West Slopes, Snowy Mountains, ACT and parts of the South Coast.
The State Emergency Service is on standby to receive calls from households which may lose power or may be flooded in over the afternoon.
The SES have advised people to move their cars under cover, secure all loose items around their homes and stay at least 8 metres away from fallen power lines.
"Keep clear of creeks and storm drains and don't walk, ride your bike or drive through flood water," a statement said.
Earlier, while Sydney was greeted with sunshine and warm weather on Friday, giving the city a welcome reprieve from the rain and gloom, thunderstorms are predicted for the weekend.
The last of the sunny conditions is expected to stick around for Saturday morning before the rain hits, with a hot 32C predicted for Penrith.
But mid-Saturday through to Sunday, rain will his eastern NSW and southeast Queensland, where a "major thunderstorm event" and a risk of flash flooding is expected.
Sky News Weather meteorologist Tristan Meyers said showers and storms would hit late Saturday.
"Sunday looks wet and terrible again," Mr Meyers said.
"We get a good start to the weekend but as Saturday wraps up it will get worse, and Sunday will just be wet."
A weather warning has been issued as yet, but a strong, upper-level, high pressure system is expected to see sever weather warnings sent out by the weather bureau by tomorrow.
On Sunday a late southerly change will cool things down a bit and it will just be a wet day without the thunderstorms.
"We're also expecting quite a lot of thunderstorm activity over the western slopes and plains on Saturday and northeast of the state on Sunday - it'll be quite a bout of stormy, showery weather," Bureau of Meteorology duty forecaster Rob Toggart said.
The combination of a low pressure trough hovering over the eastern half of NSW and a high pressure system over the Tasman Sea is generating the "burst of thunderstorms", according to Mr Toggart.
"At the moment it extends from the north west slopes and plains down to the South Coast," he said.
"At the same time there's a slow moving high pressure system over the Tasman Sea and what that's doing is feeding humid, north-easterly winds into the trough and that's what's creating the storms."
Severe thunderstorms in the Blue Mountains, west of Sydney, on Thursday left about 8500 homes without power and flooded parts of Gosford and Wyong on the Central Coast.
The region recorded 54mm of rain by 5pm on Thursday. Floodwaters caused heavy traffic and several buses to be diverted.
The Hunter Region and the state's central ranges and northwest slopes and plains were drenched as the storm extended across the area. Mount Seaview, inland of Port Macquarie recorded 90mm of rain.
Mr Toggart said the most "intense burst" of rainfall in recent weeks took place in Penrith on Wednesday, when a storm swept through the area and dumped 61.4mm of rain in just 30 minutes.
"That's really heavy rainfall," he said.
"A couple of weeks ago, when this wave of thunderstorm activity started, it dumped lots of rain over Broken Hill.
"It got more rainfall (30mm) in 10 minutes than it's had this entire year."