Australian tropical cyclone season to pull a 180 from last year
By
Adriana Navarro, AccuWeather staff writer
Published Oct 7, 2020 8:06 PM EDT
With the Australian cyclone season less than one month away, AccuWeather meteorologists say Australia may have not only a more active tropical season than the last but also one with more storms making landfall on the nation's shores.
During the 2019-2020 hurricane season, the Australian basin produced nine cyclones, slightly below the average of 11, with the first cyclone developing in a late start to the season. Cyclone Blake, which formed off of northwestern Australia on Jan. 4, 2020, came two months after the official start of the season, which runs from November to April.
The first cyclone of this season is expected to form before the end of December, kicking off a potentially more active season for the basin.
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"It should be a more active tropical season than last season with more impacts on Australia than last year," AccuWeather Lead International Forecaster Jason Nicholls said.
In particular, AccuWeather meteorologists will be keeping a close watch on the Coral Sea as a likely candidate for the first cyclone of the season. The sea -- at the very least -- will have its first development of the season earlier than last season when Cyclone Gretel formed on March 10, 2020.
Northern New Zealand averages a little over one tropical landfall each year, and it's possible that a storm originating in the Coral Sea could impact northern New Zealand, according to Nicholls. The most likely time for this would between December and April. However, the South Pacific will be less active than last year, which didn't bring any landfalls to the nation.
AccuWeather meteorologists are expecting up to 12 cyclones in the 2020-2021 season with a more even spread of storms throughout the season compared to last year, with up to six cyclones in Western Australia to the north of the Northern Territory or Queensland and four to the east of Queensland.
Of these 12 cyclones, AccuWeather is predicting seven will make landfall this season -- four in the west, two in the north and one in the east. The average number of landfalls in the Australian basin's tropical season is four to six.
On average, about five storms typically reach severe tropical cyclone status, meaning reaching maximum sustained winds of at least 118 km/h (73 mph). This year, AccuWeather is forecasting four to six severe tropical cyclones, which could result in a higher accumulated cyclone energy (ACE) index from the season.
The ACE Index, a metric used by various agencies to express the energy created by a cyclone during its lifetime, is predicted to be at average to higher-than-average levels this season. The typical ACE value for the Australian basin tropical season is 85, but this season is predicted to be anywhere from 85 to 95.
Where last season produced the majority of named cyclones during the last half of the season, there is a chance that the first half of this season may bring more activity than the second depending on how long La Niña remains.
Satellite imagery of Tropical Cyclone Blake over Western Australia after it made landfall in the Kimberly coast on Jan. 8, 2020. (NASA/NASA-NOAA Suomi NPP satellite)
La Niña is the cooler phase of the El Niño-Southern Oscillation (ESNO) climate pattern across the central and eastern Pacific Ocean. While La Niña patterns bring cooler water toward South America, they bring warmer waters to the western equatorial Pacific, around Indonesia. It's counterpart, El Niño, describes the opposite trends.
This year, La Nina will contribute to the earlier start to the season, but it will also bring cooler waters around and east of Fiji, possibly suppressing development in the area.
Meanwhile, warm waters in the southwestern Indian Ocean are expected to cool down during the summer months as the Indian Ocean Dipole (IOD) shifts from a weak negative phase during midseason to neutral, possibly leading to a slightly lower-than-normal water temperatures during autumn.
The IOD is the difference in water temperatures from the tropical western part of the ocean off Somalia to the tropical eastern Indian Ocean near Indonesia. More or less, Nicholls said, it is the Indian Ocean's equivalent to the ENSO.
A positive IOD is characterized by warm waters off Somalia and cool waters off Indonesia. The 2019-2020 season had a positive IOD, which factored into the suppression of cyclone development around Australia, especially in the west. A negative IOD would mean the opposite -- warmer waters to fuel cyclones near Australia. A shift to a neutral IOD would sap the area of some of that fuel.
This Feb. 10, 2020, satellite image released NASA shows Tropical Cyclone Uesi formed in Coral Sea off Queensisland in Australia. (NASA Worldview, Earth Observing System Data and Information System (EOSDIS) via AP)
However, even systems that have not attained cyclone status can wreak havoc.
"In addition to named tropical systems, I can see several tropical lows that should heighten the risk of flooding across northern Australia," Nicholls said. "There were 19 tropical lows last year, and there is a good chance there will be as many lows, if not more tropical lows, than last season."
Although northern Australia is not as densely populated as other areas of the nation, there are numerous mining, natural gas and oil operations that any tropical features, lows and named cyclones can negatively impact, Nicholls said.
Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.
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News / Hurricane
Australian tropical cyclone season to pull a 180 from last year
By Adriana Navarro, AccuWeather staff writer
Published Oct 7, 2020 8:06 PM EDT
With the Australian cyclone season less than one month away, AccuWeather meteorologists say Australia may have not only a more active tropical season than the last but also one with more storms making landfall on the nation's shores.
During the 2019-2020 hurricane season, the Australian basin produced nine cyclones, slightly below the average of 11, with the first cyclone developing in a late start to the season. Cyclone Blake, which formed off of northwestern Australia on Jan. 4, 2020, came two months after the official start of the season, which runs from November to April.
The first cyclone of this season is expected to form before the end of December, kicking off a potentially more active season for the basin.
CLICK HERE FOR THE FREE ACCUWEATHER APP
"It should be a more active tropical season than last season with more impacts on Australia than last year," AccuWeather Lead International Forecaster Jason Nicholls said.
In particular, AccuWeather meteorologists will be keeping a close watch on the Coral Sea as a likely candidate for the first cyclone of the season. The sea -- at the very least -- will have its first development of the season earlier than last season when Cyclone Gretel formed on March 10, 2020.
Northern New Zealand averages a little over one tropical landfall each year, and it's possible that a storm originating in the Coral Sea could impact northern New Zealand, according to Nicholls. The most likely time for this would between December and April. However, the South Pacific will be less active than last year, which didn't bring any landfalls to the nation.
AccuWeather meteorologists are expecting up to 12 cyclones in the 2020-2021 season with a more even spread of storms throughout the season compared to last year, with up to six cyclones in Western Australia to the north of the Northern Territory or Queensland and four to the east of Queensland.
Of these 12 cyclones, AccuWeather is predicting seven will make landfall this season -- four in the west, two in the north and one in the east. The average number of landfalls in the Australian basin's tropical season is four to six.
On average, about five storms typically reach severe tropical cyclone status, meaning reaching maximum sustained winds of at least 118 km/h (73 mph). This year, AccuWeather is forecasting four to six severe tropical cyclones, which could result in a higher accumulated cyclone energy (ACE) index from the season.
The ACE Index, a metric used by various agencies to express the energy created by a cyclone during its lifetime, is predicted to be at average to higher-than-average levels this season. The typical ACE value for the Australian basin tropical season is 85, but this season is predicted to be anywhere from 85 to 95.
Where last season produced the majority of named cyclones during the last half of the season, there is a chance that the first half of this season may bring more activity than the second depending on how long La Niña remains.
Satellite imagery of Tropical Cyclone Blake over Western Australia after it made landfall in the Kimberly coast on Jan. 8, 2020. (NASA/NASA-NOAA Suomi NPP satellite)
La Niña is the cooler phase of the El Niño-Southern Oscillation (ESNO) climate pattern across the central and eastern Pacific Ocean. While La Niña patterns bring cooler water toward South America, they bring warmer waters to the western equatorial Pacific, around Indonesia. It's counterpart, El Niño, describes the opposite trends.
This year, La Nina will contribute to the earlier start to the season, but it will also bring cooler waters around and east of Fiji, possibly suppressing development in the area.
Meanwhile, warm waters in the southwestern Indian Ocean are expected to cool down during the summer months as the Indian Ocean Dipole (IOD) shifts from a weak negative phase during midseason to neutral, possibly leading to a slightly lower-than-normal water temperatures during autumn.
The IOD is the difference in water temperatures from the tropical western part of the ocean off Somalia to the tropical eastern Indian Ocean near Indonesia. More or less, Nicholls said, it is the Indian Ocean's equivalent to the ENSO.
A positive IOD is characterized by warm waters off Somalia and cool waters off Indonesia. The 2019-2020 season had a positive IOD, which factored into the suppression of cyclone development around Australia, especially in the west. A negative IOD would mean the opposite -- warmer waters to fuel cyclones near Australia. A shift to a neutral IOD would sap the area of some of that fuel.
This Feb. 10, 2020, satellite image released NASA shows Tropical Cyclone Uesi formed in Coral Sea off Queensisland in Australia. (NASA Worldview, Earth Observing System Data and Information System (EOSDIS) via AP)
However, even systems that have not attained cyclone status can wreak havoc.
"In addition to named tropical systems, I can see several tropical lows that should heighten the risk of flooding across northern Australia," Nicholls said. "There were 19 tropical lows last year, and there is a good chance there will be as many lows, if not more tropical lows, than last season."
Although northern Australia is not as densely populated as other areas of the nation, there are numerous mining, natural gas and oil operations that any tropical features, lows and named cyclones can negatively impact, Nicholls said.
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Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.
Report a Typo