Destructive thunderstorms pummelled central and south parts of NSW and the ACT yesterday, bringing widespread damage. A surface trough fed by northeasterly winds was accompanied by a pool of very cold upper level air and strong wind shear, creating ideal conditions for widespread severe thunderstorms. The thunderstorms fired off from the late morning over the central NSW inland, before storming south during the afternoon and persisting into the evening over southern NSW and the ACT. Both Sydney and Canberra were battered by intense storm lines, and even a couple of supercells, causing trees and powerlines to fall down and tens of thousands of homes to lose power. In the Sydney region, large hail hit Mulgoa and parts of the northern beaches, including Manly. These was widespread wind damage across the west and north, with particularly severe damage around Glenorie due to a supercell. At Bankstown, 20mm fell in just 10 minutes, whilst wind gusts clocked 98 km/h at Badgerys Creek. Canberra was hit by one storm after another, resulting in heavy rainfall, hail and strong winds. East of Canberra, damage reports suggested there may have even been a tornado. Lightning was intense, particularly in southern NSW and the ACT during the evening, with more than 150,000 strikes being recorded across NSW and the ACT. The cold pool largely responsible for the storms is currently residing over southern NSW, although the dynamics that made Saturday so severe no longer exist. However, further storms are likely on today and into Monday, with potential for the odd severe storm remaining. Small hail is the most likely phenomenon due to the cold air remaining in the upper atmosphere. The system will clear on Tuesday, giving way to warm and dry weather for a couple of days.