THE temperature in Perth hit 40.5C, with the sweltering heatwave set to continue till at least Wednesday.
The blistering start to the day followed an uncomfortable night on Friday when the mercury dipped - barely - to 27.3C at 12.34am.
By 10am yesterday the temperature in Perth had already reached 36C.
The 40.5C top came at 1.36pm.
Perth Airport reached 40.4C just before noon. Jandakot was 39.6C by just after midday.
Pearce, 45km from Perth, was the metro region's hotspot with a blistering 42.1C, which came at 2.30pm and Gingin, 80km north of Perth, reached 41.2C by early afternoon.
Heatwave to last till Wednesday
The stifling heatwave gripping Perth will continue until at least Wednesday.
Authorities have warned people to drink plenty of water, avoid alcohol and coffee and stay indoors where possible.
St John Ambulance has reported a spike in calls for heat-related emergencies and Surf Life Saving WA said it was battling a surge in beach rescues.
Metropolitan hospitals are admitting about 10 patients a day with heat-caused ailments.
SLSWA chief executive Paul Andrew said it had conducted 25 rescues, 254 first-aid procedures and 1180 preventative actions since the heatwave started on Christmas Day.
Today's temperature is expected to soar to 41C, followed by 39C on New Year's Eve and New Year's Day.
A storm is brewing for Wednesday, which will finally bring some relief, but could cause havoc of its own with lightning and strong winds. A Western Power spokeswoman said electricity use had peaked at 3222MW in the past few days still below the year's top of 4068MW on January 25.
State Health Co-ordinator Tarun Weeramanthri has warned that the heatwave's dangers would worsen as it drags on.
"Effects build up over a number of days and people eventually become exhausted, especially with warm nights," he said.
"So you actually have to become more aware and more vigilant, as the risk increases the longer the heatwave goes on.
"The vulnerable groups are the elderly, particularly over the age of 65, the very young, and those with medical conditions."
Dr Weeramanthri said people should drink at least two litres of water a day, avoid alcohol and caffeine and use common sense when they were celebrating on New Year's Eve.
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