Page 9 - NLN Oct18

Spring is Here, and There’s Little Drought Relief in Sight

Authors: Jonathan Pollock, Climatologist, Australian Bureau of Meteorology, Catherine Ganter,
Senior Climatologist, Australian Bureau of Meteorology, David Jones, Climate Scientist, Australian Bureau of Meteorology

Niño forming in 2018 – double the usual likelihood. El Niño during Australian Bight which have roughly equal chances of warmer or
spring typically means below-average rainfall across eastern and cooler than average minimum temperatures.
northern Australia. What does this mean for the drought and bushfires?
Three out of five international models are forecasting that a positive Like the rest of the country, the Bureau is hoping that farmers in
Indian Ocean Dipole event is also possible this spring. A positive drought-affected areas get the rainfall they need soon. But this
IOD during spring typically means below-average rainfall in central outlook isn’t the news many want to hear.
and southern Australia. When El Niño and a positive IOD coincide, Last weekend’s rainfall over northeastern New South Wales
their drying influences can be exacerbated. and southeastern Queensland was welcomed by most, but
So, what’s the outlook for Spring? unfortunately it was well short of what was required for a recovery
With a reasonable chance of both El Niño developing and a from the longer-term rainfall deficits. Many locations on the east
positive Indian Ocean Dipole, the outlook for spring shows below- coast are well below their average year-to-date rainfall totals.
average rainfall is likely over much of the southeast and parts of Rainfall deficiencies for the first seven months of 2018 in areas of
the northeast and southwest. The rest of the country has a neutral western NSW, northwest Victoria and eastern South Australia widely
outlook, showing no strong push towards a wetter or drier than show rainfall totals in the lowest 5% of the 118 years of record. It
average three months. would take many months of above-average rainfall to return to
Inland areas are typically dry at this time of year, so the neutral average levels.
outlook in the arid interior typically implies that low rainfall is The above average temperatures in 2018 so far, combined with
likely. No part of the country favours above-average rainfall in the below average rainfall and dry vegetation, mean a higher likelihood
spring outlook. of fire activity in parts of southern Australia. The warm and dry
Spring days are likely to be warmer than average across Australia, outlook for spring means the drought in parts of the country’s east
with the highest chances (greater than 80%) over northern and is likely to continue.
western Australia. Most of the country is likely to have warmer
than average nights this spring, except for areas around the Great
October 2018 www.northlakesnow.com.au 9