La Nina Maintains a Wet East Australia Q4/2022 Climate Pattern

Executive Summary: The Climate Impact Company month 1-3 ahead climate forecast for Australia valid for Q4/2022 is updated. The outlook indicates presence of a persistent upper trough across mainly Southern Australia each month. This pattern motivates a wet climate in the East where soil moisture is already abundant. The upper trough also defeats any significant heat for mid-spring to early meteorological summer. Patchy dryness is closely watched on the Australian South Coast and in northwest continent. However, drought risk is low for summer 2022-23 and excessive wet weather in the East is a much larger concern.

Climate: The Q4/2022 climate outlooks for Australia are based on a constructed analog most-correlated to the persistence and peaking negative phase of the Indian Ocean dipole (-IOD) and third spike in La Nina (of the past 3 years). Additionally, influence of the climate pattern motivated by the marine heat wave oceanic regime near and east of New Zealand is heavily considered.

October 2022: The October constructed analog is in good agreement with operational models. Indicated is a persistent upper trough centered on the southern half of Western Australia occasionally extending eastward to New South Wales. Sensible weather results include a cooler than normal climate for the southern 2/3 of the continent for mid-spring. Northern Queensland is warmer than normal. The upper trough supports a wet climate for the East Coast, most prominently near the Queensland/New South Wales state line. Parts of the North Coast are also wetter than normal.  The forecast trend from the previous outlook is wetter and cooler.

Fig. 1-2: The Climate Impact Company constructed analog temperature and precipitation anomaly climate forecasts for October 2022.

November 2022: In November, a weak upper trough persists across central continent. An amplified ridge is forecast southeast of Australia. The forecast may be too cool eastern areas possibly warmer than indicated. Additionally, the wet forecast in the East may be wetter. Potential for an unusually warm month in Victoria.  The forecast trend from the previous outlook is cooler except warmer in Victoria and similarly wet in the East.

Fig. 3-4: The Climate Impact Company constructed analog temperature and precipitation anomaly climate forecasts for November 2022. 

December 2022: Persistent broad trough across Australia with core position on the South Coast continues into early meteorological summer. Sensible weather result is less hot than normal across parts of southern continent. The West and Northwest Coast are hotter than normal. The wet regime on the East Coast will continue. The outlook is similar to previous except wetter on the Queensland Coast.

Fig. 5-6: The Climate Impact Company preliminary constructed analog temperature and precipitation anomaly climate forecasts for December 2022.