Well, that was spectacular.

As we wrote yesterday, Sydney has been exceptionally wet in recent times. Eighteen of the past 22 days have now recorded at least some rain.

But the most dramatic display of this prolonged soggy spell - caused by a relentless onshore flow typical of La Nina - came on Monday evening, as storms swept across the harbour city.

Image: The calm before the storm at Bradleys Head. Source @rmd_imagery on Instagram.

The storms dumped 13 mm of rain at the city's "official" weather station at Observatory Hill, and while rainfall totals were not exceptional across the city, dramatic scenes accompanied the onset of the brief deluge.

Numerous lightning strikes were also reported. More than 38,000 lightning strikes were detected within 100km of Sydney, more than 8,000 of which hit the ground.

Image: The Sydney suburb of Harris Park, from under a Bridge on the M4 freeway. Source: @debojit.t.chakrabarty on Instagram.

Newcastle also experienced some dramatic cloud formations from the broad storm front, which lashed much of the NSW coastline and nearby ranges and tablelands.

Image: Clouds were king of the castle in Newy yesterday. Source: Ian Nord photography

"There's a high chance of again seeing thunderstorms rolling through the Sydney area this afternoon and early evening," Weatherzone meteorologist Esteban Abellan said.

"Storms are most likely in the city's west, where they may bring gusty winds and large hail. They will be more isolated in eastern suburbs.

"On Wednesday, the instability will start to move further north. We could still see the odd storm, mainly on the Blue Mountains.

"A ridge of high pressure will start to build along the coast later in the week, inhibiting any storms from developing in the Sydney region from Thursday to the end of the week."