‘Absolute humidity’: Sydney’s muggy weather set to end

Sydney has sweated through a low-intensity heatwave on Saturday with “absolute humidity” pushing temperatures to feel up to 5 degrees higher than they were.

While some reprieve from the heat is expected on Sunday, severe thunderstorm warnings for the city were cancelled on Saturday evening.

The city’s western suburbs, where Penrith’s “Pondi” beach reopened on Saturday, were most likely to be hit by heavy rainfall. Localised flash flooding, damaging winds and large hail can now be ruled out, weather bureau meteorologists said.

One of the first beachgoers, Lidia Jaszczyszyn, enjoying the waters shortly after the opening of Penrith Beach on Saturday.Credit: Dion Georgopoulos

“There is a low-intensity heatwave over Sydney at the moment, which is expected to end on Sunday as drier, cooler air moves over NSW behind the passage of a cold front,” they said.

While the thunderstorm forecast for Sydney was cancelled, the warm and humid air mass combined with a trough of low pressure was driving “very dangerous thunderstorms” that were likely to produce large, “possibly giant hailstones”, and damaging and “locally destructive winds” across southwest NSW, including Griffith, where wind gusts of 115 km/h were recorded.

In Sydney, the humid air pushed dew point temperatures above 24 degrees, leading to uncomfortable conditions and possible heat stress for pets and sensitive people.

Wet weather in Maroubra today is predicted to continue this afternoon before easing tomorrow.Credit: Steven Siewert

On humid days, it is harder for sweat to evaporate and cool the body because the air circulating the skin is packed with water.

“Heat and tropical moisture have been dragged across NSW by several cold fronts and trough systems in the previous weeks, maintaining high temperatures and humidity in Sydney,” the Bureau of Meteorology said.

“These conditions are favourable to thunderstorm development and are also responsible for the high humidity. Some reprieve is expected during next week from this pattern.”

Temperatures are expected to be in the high 20s in the city, and above 30 degrees in the west, on Sunday before moving down to 24 degrees on Monday. But humid and hot weather is likely to continue during the week ahead.

The early summer heat forced the NSW government to reopen Penrith’s beach, nicknamed “Pondi”, earlier than expected for its second season on Saturday after a $2.5 million renovation.

The beach is open from 10am to 7pm every day until April 27. Locals will not need to book a parking space as they did last year, with 300 spots now available.

The government spent $1.7 million opening the beach last year, which drew more than 215,000 visitors, including many whose closest ocean beach is more than an hour’s drive away.

The long-range forecast for the NSW coast is for higher-than-average rainfall.

Get the day’s breaking news, entertainment ideas and a long read to enjoy. Sign up to receive our Evening Edition newsletter here.