By Eugenio Hackbart, Chief Meteorologist for MetSul Weather Center in Sao Leopoldo, state of Rio Grande do Sul, Southern Brazil

May 2007 will go to history as one of the coldest starts to climatic winter ever observed in South America. A brutal cold wave brought record low temperatures, widespread frost, snow and major energy disruption. The death toll for the 10-day cold wave was the highest for any single weather event in Argentina in recent history. Authorities confirmed 34 deaths directly or indirectly linked to the polar air incursion. Some of the fatalities were caused by hypothermia, but the majority of the victims died in consequence of fires and gas inhalation. The below-freezing temperatures prompted residents to turn on defective heaters using gas, wood and kerosene. The toxic but odorless carbon monoxide fumes and other lethal gasses were blamed for many of the deaths. In Cordoba, seven children died in a fire initiated by an improvised heater device. In the southernmost state of Rio Grande do Sul in Brazil one child died due to hypothermia.

The cold snap led to electricity and natural gas shortages, idling factories and taxis and causing sporadic blackouts in Argentina, according to press reports. Millions of residents fired up space heaters, straining Buenos Aires’ electrical grid for three nights and forcing authorities to slash power supply nationwide and briefly cut domestic natural gas provisions and exports to Chile. Many factories went idle when distributors shut off or reduced gas supplies to give priority to homes. Government regulators also ordered an 800-megawatt electricity cut nationwide for four hours, which led to sporadic blackouts in the capital Buenos Aires. Grumbling taxi drivers waited for hours in lines stretching several blocks to fill up their black-and-yellow cabs with scarce compressed natural gas. The shortages also had a ripple effect in neighboring Chile, where authorities scrambled to provide energy after Argentina slashed natural gas exports.

Temperatures hit the freezing point or dipped below for three successive nights in the Argentinean capital. Such cold is rare for the southern-hemisphere autumn in Buenos Aires, which normally sees temperatures in the 40s and 50s Fahrenheit or higher this time of year. According to the Servicio Meteorologico Nacional (Argentina’s National Weather Service), the low temperature of 0.3ºC registered in Downtown Buenos Aires was the lowest for the month of May since May 29th, 1962. The city also suffered the lowest windchill value observed in May for the last 36 years. On May 28th, the temperature at midday in Buenos Aires was only 3.7ºC, an unprecedented value in recent history.  Read more and see some amazing photographs here.