Thunderstorms developing over northeast New South Wales and southeast Queensland this afternoon are just a preview for an action-packed Friday. The first storm of this late-week light show bubbled up on the Northern Tablelands of New South Wales around midday today, between Tenterfield and Bonalbo. Shortly after the first lightning strike, the Bureau of Meteorology issued a severe thunderstorm warning for damaging winds. Storms will continue to develop over northeast New South Wales this afternoon and may also spread to the state's central ranges and northern inland, as well as parts of southeast Queensland. Most storms today will not be severe, although damaging winds and hail can't be ruled out, along with bursts of heavy rain underneath slower-moving cells. Friday will be a more volatile day over southeast Queensland and northeast New South Wales, with severe thunderstorms likely to produce damaging winds, large hail and heavy rain. A couple of ingredients will combine tomorrow to produce violent thunderstorms. Firstly, winds at the surface will converge, or clash into each other, causing air to lift away from the ground. As this air rises, it will encounter a pool of cold upper-level air passing overhead, further enhancing its journey upward. This setup is a recipe for intense thunderstorm development. Storms will develop on Friday inside a triangle between the Queensland's Central Highlands, the Central Tablelands in New South Wales and the Gold Coast. Severe thunderstorms are most likely over the northern slopes and ranges of New South Wales and over Queensland's far southeast inland, on and east of the Granite Belt. Storms are most likely to affect the coast around the Gold Coast and Northern Rivers district, although they can't be ruled out further north and south, including Brisbane. More storms are likely on the weekend, so be sure to keep a close eye on the latest warnings during the next few days.