The majority of the country is cloud free under the influence of a broad, dominant high pressure system centred in the northern Tasman Sea. A high pressure system in the Indian Ocean is creating some scattered low level cloud of the southwestern corner of Western Australia. A trough stretches from the northwest to the southeast of Australia. Ahead of the trough a band of patchy high level cloud lies over northern South Australia, and New South Wales. In southern South Australia, Tasmania and Victoria, low level cloud is drawn onshore behind the trough.