Sydney, Melbourne, Brisbane weather: Warning issued

Aussies are being warned to brace for even more wild weather, with heavy rain, damaging winds and thunderstorms set to bring a wet end to spring.

Another round of dangerous thunderstorms are forecast for parts of Victoria, NSW and Queensland as a cold front moves over the country's southeastern states.

'The atmosphere will be very unstable in southeastern and eastern Australia starting this weekend, with warm and humid air to be lifted by the cold front and trough above the surface, which will help create large thunderstorms,' explained Weatherzone Meteorologist Ashleigh Madden.

'This unstable atmosphere is likely to generate some severe thunderstorms, with heavy rainfall and damaging winds, which are the main risks on Monday.

'The cold front and associated thunderstorm activity is also expected to bring significant rainfall to the northern ranges in Victoria and southeastern NSW.'

Showers are forecast for Tasmania across the start of the week, while the risk of severe thunderstorms threatens southern Queensland on Monday.

On Tuesday, tropical moisture is predicted to bring heavy rain to Western Australia 's west coast.

Meanwhile, rising heat and heightened fire risks are expected in southeast Australia starting Friday, with temperatures forecast to climb into the high 30s and low 40s.

Sydney was battered by a severe thunderstorm on Sunday, which caused flight cancellations and dislodged a road plate near the Harbour Bridge.

The road plate, measuring one square metre and made of concrete and steel, dislodged during the storm after 8pm, damaging 25 cars and causing a two-hour traffic delay for motorists on the Harbour Bridge.

NSW Secretary of Transport Josh Murray apologised to the motorists and said Transport for NSW would pay to repair the damage to cars caused by the road plate.

'It was a nightmare,' Murray told 2GB's Ben Fordham on Monday.

'Let me apologise to anyone whose car was damaged or anyone else who was caught up for about two hours.'

Meanwhile, travellers at Sydney airport were hit with more than 20 flight cancellations due to the storm activity.

The State Emergency Service responded to 278 calls across the state, with 81 in Sydney, 50 in southern NSW and 49 in western NSW.

The strong winds also caused scattered power outages across Sydney including Auburn, Central Coast and around Newcastle.

Monday: Showers, up to 7mm of rain. Chance of a thunderstorm. Winds up to 25km/h. Max 27C.

Tuesday: Slight chance of showers. Winds up to 20km/h. Min 18C Max 23C.

Wednesday: Slight chance of a shower. Winds up to 20km/h. Min 17C Max 25C.

Thursday: Slight chance of a shower. Winds up to 20km/h. Min 17C Max 23C.

Monday: Medium chance of showers. Winds up to 20km/h. Max 19.

Tuesday: Slight chance of a shower. Winds up to 25km/h. Min 12C Max 18C.

Wednesday: Partly cloudy. Winds up to 25km/h. Min 11C Max 19C.

Thursday: Sunny. Winds up to 25km/h. Min 11C Max 30C.

Monday: Mostly sunny. Slight chance of a shower. Chance of a thunderstorm. Winds up to 25km/h. Max 29C.

Tuesday: Showers. Up to 30mm of rain. Chance of a thunderstorm. Winds up to 20km/h. Min 21C Max 25C.

Wednesday: Showers. Up to 20mm of rain. Winds up to 25km/h. Min 20C Max 24C.

Thursday: Showers. Up to 8mm of rain. Winds up to 30km/h. Min 20C Max 24C.

Monday: Chance of a shower. Winds up to 25km/h, Max 23C.

Tuesday: Slight chance of a shower. Winds up to 25km/h. Min 7C Max 24C.

Wednesday: Slight chance of a shower. Winds up to 25km/h. Min 9C Max 26C.

Thursday: Cloudy. Winds up to 25km/h. Min 9C Max 23C.

Monday: Showers. Max 17C.

Tuesday: Partly cloudy. Winds up to 25km/h. Min 8C Max 19C.

Wednesday: Slight chance of a shower. Winds up to 30km/h. Min 8C Max 17C.

Thursday: Sunny. Winds up to 25km/h. Min 6C Max 21C.

Monday: Medium chance of showers. Chance of a thunderstorm. Winds up to 40km/h. Gusts to 60km/h are possible. Max 32C.

Tuesday: Medium chance of showers. Chance of a thunderstorm. Winds up to 35km/h. Min 19C Max 29C.

Wednesday: Showers. Up to 8mm of rain. Chance of a thunderstorm. Winds up to 20km/h. Min 17C Max 25C.

Thursday: Medium chance of showers. Winds up to 25km/h. Min 16C Max 23C.

Monday: Mostly sunny. Slight chance of a shower. Winds up to 30km/h. Max 22C.

Tuesday: Sunny. Winds up to 30km/h. Min 10C Max 25C.

Wednesday: Sunny. Winds up to 25km/h. Min 11C Max 28C.

Thursday: Sunny. Winds up to 25km/h. Min 15C Max 33C.

Monday: Showers. Up to 9mm of rain. Chance of a thunderstorm. Winds up to 20km/h. Max 35C.

Tuesday: Showers. Up to 20mm of rain. Chance of a thunderstorm. Min 26C Max 33C.

Wednesday: Showers. Up to 15mm of rain. Chance of a thunderstorm. Winds up to 20km/h. Min 25C Max 33C.

Thursday: Showers. Up to 15mm of rain. Chance of a thunderstorm. Min 26C Max 33C.