La Nina To Enhance Cyclones, Rain and Storms This Season!
Issued 14th August 2020.A developing weak La Nina weather pattern in the Pacific Ocean is expected to greatly influence Australia’s weather this year! Large parts of Northern and Eastern Australia could see above average rainfall, while Queensland and the Northern Territory will have to watch for a higher number of cyclones. A big storm season is also tipped across NSW and QLD. Above image via JAMSTEC
The latest global model data has just been updated and it’s indicating a weak La Nina weather pattern will develop in September. Even if the sea surface temperatures fall just short of the BOM’s -0.8C La Nina threshold, a huge area of cooler than normal sea surface temperatures in the Equatorial Pacific Ocean has already developed anyway. This will now be the primary climate driver across the South Pacific where it will significantly increase the moisture feed across Northern and Eastern Australia during the next 6 months.
High pressure systems are forecast to be further East near New Zealand feeding huge amounts of moisture across the Tasman and Coral Sea deep into surface troughs across QLD, NSW the ACT and VIC. These troughs will generate showers, rain areas and thunderstorms with many storms being SEVERE containing Heavy Rainfall, Flash Flooding, Large Hail and Damaging Winds. They troughs are likely to be quasi stationary moving East to the coast on occasions then redeveloping inland shortly after.
Increased North West monsoon winds coupled with more frequent MJO positive phases and a stronger monsoon trough are also likely across Northern Australia and Northern QLD. This should bring increased widespread rainfall and storms with higher chances of tropical low and tropical cyclone development both in the Gulf of Carpentaria, Arafura Sea and Timor Sea. Tropical systems in these areas can often travel through Central Australia bringing widespread rain and flooding.
Due to the increasing the Easterly trade winds across the Central and Western Pacific, the ITCZ (Inter Tropical Convergence Zone) in the Coral Sea and Solomon Sea is expected to be much more stronger and active tis season. Tropical Lows and Cyclones will have a much higher risk of development in these areas which could easily track West and South West posing a significant risk to Queensland, not just once but multiple times.
We will be working very hard with forecasts and warnings this year by the looks of things…. Not to mention chasing hard!