TOMORROW is the official start of summer and to announce its arrival, the weather gods have sent a clear message to get ready for some extremely hot weather.
The Bureau of Meteorology has issued a warning that the next couple of days will bring heatwave conditions to the Tweed and temperatures will remain well above average until Monday.
However, the traditional definition of a heatwave differs from the current conditions experienced in the Tweed.
The accepted definition states conditions can only be called heatwaves if an area experiences five straight days of temperatures which are at least five degrees above average.
Bureau of Meteorology NSW weather service manager Andrew Treloar said, according to the NSW state disaster planning description, the unusual temperatures warranted calling the conditions a heatwave
"We've had mild conditions over the last few years and haven't faced similar conditions since 2009.
"The current situation doesn't exceed the 2009 event, however, any time we face heat like this there are issues regarding public health.
"We advise residents to keep hydrated and cool where and whenever possible," Mr Treloar said.
The bureau forecast temperatures will reach between 31° and 38° today and rise to between 32° and 39° on Sunday.
Monday will finally bring some relief with temperatures dropping slightly but noticeably to the low to mid 30s.
The extreme conditions are caused by a slow-moving high pressure system over the Tasman Sea which is directing hot and humid northerly winds into a weak low pressure trough over Western NSW.
The conditions forecast for this weekend can result in people suffering from heat stroke which can have serious and even fatal consequences.
Symptoms include fast breathing and increased pulse rates caused by a failure of people's cooling processes.
Animals are also at risk and pet owners are advised to provide shade and water as they become lifesaving essentials.