La Niña has been declared for Australia.
This means higher rainfall and lower temperatures for central and eastern Australia, which will likely bring a wetter and cooler summer for Broken Hill.
The Bureau of Meteorology (BOM) Head of Operational Climate Services Andrew Watkins says La Niña will bring more rain and lower temperatures, but this year’s weather system is weaker than the strongest on record which was in 2010-2012.
“The La Niña is likely to persist until at least January 2022, and possibly through the summer as a whole,” he said.
“La Niña also occurred during spring and summer of 2020-21. Back-to-back La Niña events are not unusual, with around half of all past events returning for a second year.”
Broken Hill has received its highest monthly rainfall for 2021 this month with 75.8 millilitres so far and 215.6 millilitres for the year.
The 2020 La Niña only gave Broken Hill 21 millilitres in December and 26 millilitres January 2021.
Broken Hill received 56 millilitres of rain in November 2010 followed by 116 and 121 millilitres in January and February 2011 respectively.
The four weather indicators for La Niña include cooler water temperature in the tropical Pacific Ocean, decreased cloud around the dateline in the Pacific, increased trade winds which travel towards Australia across the Pacific Ocean and lower surface pressure in the Western Pacific Ocean.
Whilst it means higher rain and lower temperatures for Australia it means lower rainfall for Africa, South America and possibly increased hurricanes in the USA.