Brisbane turns on the heat for G20 summit as monthly records melt Scorcher: Hundreds of tourists and Brisbane locals spend their G20 public holiday at Streets Beach on Brisbane's South Bank. Photo: Jenelle Stafford Leaders attending the G20 summit in Brisbane may not get to talk much about climate change but it might be harder to avoid discussing the weather. The mercury is forecast to climb to 40 degrees on Sunday in Brisbane and in suburban areas as high as 42 degrees as a week-long heatwave makes its way to eastern Australia. The city is expecting a top of 35 degrees on Saturday. Brisbane's record for the month goes all the way back to November 18, 1913, making any new peak a once-in-a-century event, the Bureau of Meteorology said. Northern NSW has also endured another sweltering day with 44.5 degrees recorded at Walgett just before 2pm on Saturday. Bourke on Friday, with its maximum of 45.8 degrees, set an early-season record in data for the town going back to 1871. Alice Springs also set a notable peak from the heatwave, with Thursday's maximum recorded by the bureau as 44.6 degrees - a top that exceed previous records for both November and December. Record warmth A deal by the US and China to cut carbon emissions announced earlier in the week in Beijing has meant climate change has remained a prominent subject despite efforts by the Abbott government to steer discussion to jobs and growth. US President Barack Obama also spoke at length about climate change in his speech to the University of Queensland on Saturday. Adding to the cacophony on climate has been the release of new figures by the Japan Meteorology Agency revealing that last month was the hottest October in records going back to 1891. The global average surface temperature last month was 0.34 degrees above the 1981-2010 average, easily eclipsing the previous largest anomaly of 0.24 degrees set in October 2003. The warm October extends the warmest ever April-September period, according to US agencies, and increases the likelihood that 2014 will become the hottest year on record. The previous record warmth is generally viewed as a tie between 2005 and 2010. For Australia, maximum temperatures last month were also the warmest on record for October, with an anomaly of 2.76 degrees compared with the long-term average. By mean temperatures, it was the second warmest October, the Bureau of Meteorology said. For the first 10 months of the year, Australia's area-averaged maximums were running at the fourth warmest on record and mean temperatures were the fifth warmest. Last year was Australia's hottest since the bureau began national records in 1910.