Red alerts have been issued for almost 3,000 towns and cities across Brazil, which have been experiencing an unprecedented heatwave.<br />'' <br />''The municipal authorities has said that Rio de Janeiro recorded 42.5 °C on Sunday, a record for November.<br />'' <br />''Brazil's National Institute of Meteorology reported that the city of Sao Paulo saw average temperatures of 37.3 °C yesterday afternoon.<br />'' <br />''It has issued red alerts for a large part of the country. This indicates that temperatures may be 5 °C above average for longer than five days and could pose a serious danger to health.<br />'' <br />''<span style="color: #222222;">More than a 10 crore people have been affected by the heatwave, which is expected to last until atleast Friday. The officials have attributed it to the El Niño phenomenon and climate change.</span><br />