Sydney's run of unusually cold mornings will extend well into next week as mostly clear skies combine with light winds and a frigid air mass to sink the mercury.

Enjoy the sunshine at the start of this week, as the the grey clouds and rain that have become all-too-familiar visitors in recent times are due to roll in again come Wednesday.

The remarkable global heat for 2015 is not yet over and already forecasters are predicting next year will be hotter again - marking three years in a row of record annual warmth.

Thunderstorms have rumbled their way across Sydney for the ninth consecutive day, with more thunder and lightning on the horizon throughout Monday morning and into the afternoon.

The trough that brought a series of storms to Canberra on Saturday is expected to affect the region until Monday.

Wednesday night may be on the cool side for Queensland visitors to the opening State of Origin match at Homebush but the overall conditions could hardly be better for football.

They said it would never fill. Now it has spilled.

In a town regarded as one of the world's hottest, Marble Bar locals are still reminded to take care as the mercury hit 48 degrees Celsius on Monday.

Sydney will likely come close to notching its hottest day this late in the summer for 12 years - and there won't be much early relief.

Sydneysiders can expect rising humidity in coming days, making the apparently endless summer seem a bit more uncomfortable.

Going to Sea World isn't a walk in the park for the animals kept in captivity, say campaigners.

Spring's full bloom will be on show this week in ways that hay fever sufferers will be all too aware.

Unless you've been inside a 200kmh blast of wind it's hard to imagine the tremendous natural force behind it.

After 16 years of observations, the world's new lightning capital has been named.

May and autumn will come close to being a record warm ones for Sydney, the state and the rest of Australia as the giant El Nino added a hot overlay to temperatures that are rising in the background here and in most parts of the world.

Unprecedented rain in Japan unleashed heavy floods that tore houses from their foundations, uprooted trees and forced thousands from their homes.

Sydney awoke to a frigid Saturday morning, with temperatures dipping to a brisk 7.3 degrees in the CBD at 7:15am.

Temperatures in Canberra reached 38.5 degrees as the region's first heatwave of the year peaked on Wednesday.

Sydneysiders look set for a soggy commute to end the working week, as an intense low pressure system off the coast delivers widespread showers, wind and large and powerful surf conditions to the city.

Canberrans still wringing themselves out from the wettest June on record shouldn't put away their gumboots just yet.

A fierce blast of winter has prompted a severe weather warning for most of southern NSW, including Sydney.

Sydneysiders got down to cleaning up their damaged properties on Friday after destructive winds accompanying a sudden cool change broke up the 40-degree heat a day earlier.

Federal Water Minister Keith Pitt says the government remains determined to build new dams in the Murray-Darling Basin, rejecting comments from a leading researcher that climate change would reduce the likelihood that they would fill. 

Wild weather across the country has claimed three lives following three incidents of cars being swept away in flood waters.

A much-anticipated cool change took its time making it to Sydney, dragging out another unseasonably hot day.