Thousands of homes across Perth were without power on Tuesday as the city endured its fourth straight day of over 40 degrees Celsius.
But after some 4,000 properties were blacked out earlier in the day, Western Power said fewer than 1,000 homes remained offline as of 3:00pm.
The utility said most of the 35,000 West Australians who sweltered through the hottest Christmas Day on record without air conditioning had been reconnected.
It said crews had been working around the clock over the last few days to bring that number down.
The temperature in Perth reached 40.7C at 2:19pm, exceeding the forecast maximum of 39C and marking the city's fourth consecutive day above 40C.
The city has never before experienced a similar run of high temperatures in December.
Areas still affected by the power outages on Tuesday afternoon included Lower Chittering, Scarborough and Mosman Park.
Minister orders review into blackouts
Energy Minister Bill Johnston apologised for the outages, admitting Western Power had fallen below its own reliability standards, and said he would order an independent review into the situation.
"I know through this extraordinarily hot time how inconvenient it was to lose power," he said.
"We're happy to be very transparent, and we will review the lead-up to this situation ... and any lessons learned out of this period."
He said there were several causes for the power failures, including heat and physical interruptions such as branches hitting power lines.
The risk of fire also reduced Western Power's capacity to repair affected areas.
"Work that Western Power does has to be delayed ? because of the bushfire risks," Mr Johnston said.
"We don't want to start fires, and so therefore we make sure we do this in coordination."
'Really unfortunate': Western Power
Earlier, Western Power's Zane Christmas said many of the required repairs had been delayed due to fire weather warnings and hot conditions.
"It's just a combination of lots of different issues, mostly weather-related," he said.
"Ordinarily, we would be able to restore them quite quickly.
"But given the temperatures and the fire danger index that we're experiencing, we just can't restore supply until that index comes down a little bit and it's safe to do so.
"So it's really unfortunate. We understand the impact on the community, but it's just resulted in some really long outages."
iiNet blames heat for email, internet issues
The hot weather has caused issues for Perth-based internet service provider iiNet, with customers around Australia reporting they have been unable to access their emails over the festive period.
The ABC was told the wait time to speak to a phone operator was more than one hour when it tried to get through to technical support on Tuesday.
An automated message stated: "Some customers using webmail may receive an error or timeout. We are working on restoration at the highest priority".
The company's website is back online after it was unavailable on Boxing Day, when a notice on the site stated it was down "due to extreme weather events in WA".
Cool change on horizon
Bureau of Meteorology (BOM) duty forecaster Jessica Lingard said the hot weather was being caused by a broad trough extending offshore from the west coast, which was pulling hot, dry air from inland WA into the south-west of the state.
The mercury is expected to drop from Thursday when that trough has moved onshore.
"So we will see the humidity increasing and temperatures cooling and we'll get that nice westerly breeze instead of these dry north-easterlies," Ms Lingard said.
But it will still be a scorcher on Wednesday, with a maximum forecast of 38C before it drops to 32C on Thursday.
Perth maximum forecast:
Tuesday forecast for regional cities and towns:
© ABC 2021
00:46 AEDT Severe thunderstorms are expected to lash eastern parts of the state today as Victoria continues to count the cost after days of wild weather.