Mere hours after our Total Lightning Network went peaceful over the Australian continent, the Himawari satellite caught a clear, book photo of the arrival of Australia’s cool season. A couple of identifying functions need to capture your eye: A band of cloud streaming over northern WA and towards the country’s interior An unique cleaning of cloud from the majority of the NT’s Top End, and A band of cloud crossing to the south of WA Turns out, all 3 of these functions indicate something: winter season is knocking at the door. Image: Himawari satellite images and imply sea level pressure (ECMWF) over Australia on the early morning of Saturday, April 27th, 2024. 1. Subtropical jet migration If you follow our weather condition stories, this may appear slightly familiar; the last time we pointed out a comparable weather condition pattern was last July, throughout the heart of winter season. One of 2 primary jet streams impacting the Australian area, the more northward subtropical jet stream, is moving north and bringing throughout warmer, damp air from the Indian Ocean. As this flight with the stream over the Australian mainland, it meets cooler air and increases over it, producing wispy, high level cirrus cloud. Image: 200hPa jetstream winds (ECMWF) overlaid on Himawari satellite images from Saturday early morning. 2. The northern dry season Whilst not formally beginning up until May, northern Australia is starting to reveal indications of the dry season, as the damp winds begin to turn more southeasterly, reducing wetness. The dry season marks a 6 month duration of clearer skies and drier (typically gusty) interior winds, especially over the Northern Territory. Optimum temperature levels still reach the low 30s throughout the Top End’s dry season, which is likewise its fire season. Image: Oracle cloud cover, revealed in oktas, overlaid on Himawari satellite images from Saturday early morning, revealing mainly clear skies over the Northern Territory. 0 oktas suggest clear skies, while 8 oktas show entirely cloudy skies. High jet stream cloud can be seen over the bottom left of the image. 3. Cold fronts Cold fronts can cross the Australian Bight at any time of year however are typically reduced throughout the warmer months as the ‘subtropical ridge’, or broad location of high pressure, tends to be over the south of the continent at this time, guiding fronts well into the Southern Ocean. Throughout cooler months, this ridge usually moves north to main Australia, enabling fronts to propagate from west to east over southern parts of the nation, bringing boosted wind and showers. Image: Forecast 850hPa winds (GFS) as a cold front crosses south of WA on Saturday night. Due to the fact that this front is additional south than the mainland, locations consisting of Perth seek to lose out on considerable winds and rains. As we move into the winter season, cold fronts and other winter season systems must begin to effect southern Australia, while the dry season grabs the north. Be sure to keep up to date with the newest cautions and projections. Keep in mind to media: You are welcome to republish text from the above news post as direct quotes from Weatherzone. When doing so, please recommendation www.weatherzone.com.au in the credit.
Indications showing Australia’s cool season arrival – Weatherzone
