Late-Season Storms for SE QLD & NE NSW Ahead of Coastal Low and Increasing Showers

Weatherwatch
Apr 21
3 min read

April 21, 2025

Areas of northeastern NSW and southeast Queensland are in for some late-season shower and storm activity today as instability builds ahead of an upper cold pool of air. That same system is expected to induce a coastal low tomorrow off the NSW coastline, bringing increasing showers to southern and central parts of the state. These showers are likely to extend northward later in the week as the low slowly shifts.

C3 forecast precipitation shows a band of showers and storms moving through SE QLD & NE NSW this afternoon and evening. Source: Weatherwatch MetCentre.

Severe Storms Possible - But Very Isolated and Mostly in Northeast NSW

Storms in April aren’t unusual in eastern Australia, it’s a time of year where the battle between lingering summer warmth and returning winter dynamics can spark instability.

Today, an upper cold pool of air is pushing into NSW, lowering temperatures in the upper atmosphere. When combined with a surface trough across northeastern NSW and southeast Queensland, this will support a few showers and isolated storms.

An upper low (500mb temperatures) is helping to drive elevated levels of instability (CAPE). Source: Weatherwatch MetCentre.

Some storms, particularly in northeastern NSW could bring brief damaging winds and large hail, though activity is expected to remain isolated. Across southeast Queensland, severe storm risk is lower due to slightly warmer air aloft, which should temper intensity. Even Brisbane could see a few rumbles but any stronger storms should favour areas around the border and southwards.

Comparison ACCESS forecast sounding from NE NSW compared to SE QLD showing stronger, and taller instability south of the border. Convection in SE QLD will be low-topped which is likely to reduce lightning frequency. Source: Weatherwatch MetCentre.

Unlike recent rain events that were dominated by heavy rainfall and flash flooding, today's risk of flash flooding is reduced. That’s thanks to faster storm movement, with cells expected to track east at around 40km/h—limiting the time they linger over any one area.

Coastal Low to Develop Tomorrow

By tomorrow, the same upper cold pool is expected to generate a low off the NSW coast.

This low will bring gusty winds and frequent showers to southern and central NSW, particularly during Tuesday and Wednesday.

It’s worth noting this will not be an East Coast Low. East Coast Lows are typically deeper systems that can deliver widespread damaging winds and torrential rainfall—this system is expected to be much weaker.

EC rainfall during the next 4 days showing increased rainfall across areas of the NSW coastline. Source: Weatherwatch MetCentre.

EC wind gusts show the development of a small low off the NSW coastline that tracks northwards this week. Source: Weatherwatch MetCentre.

A Wetter Finish to the Week for SE QLD

Initially, the coastal low will actually bring drier weather to southeast Queensland on Tuesday. But as the system tracks northward (thanks to a high to the south pushing the low to the north), it’s likely to push moisture into the region by late Wednesday and Thursday, leading to more frequent showers.