Canberra, Feb 25 : A high risk cyclone warning has been issued for Australia's Northern Territory (NT). The Bureau of Meteorology (BoM) on Thursday night upgraded the cyclone threat for Saturday and Sunday from "moderate" to "high". It said a tropical low system in the Timor Sea northwest of Darwin was expected to increase in intensity to a category two storm by Sunday morning and make landfall, bringing with it heavy rain and damaging winds, Xinhua news agency reported. "The future movement and development of this low is uncertain and several scenarios are possible," BoM NT manager Shenagh Gamble told News Corp Australia. "Gales with gusts of up to 100 kms per hour may develop on the Tiwi Islands early on Saturday morning. Extending further south to the mainland NT later that day." "We encourage people to stay up to date with warnings." A cyclone watch zone has been established stretching from Point Stuart east of Darwin to Kalumburu more than 580 km away in Western Australia (WA). A flood watch has been issued for coastal regions. Mark Cunnington, NT's Northern Command operations manager, advised everyone in the cyclone's possible path to prepare for floodwater and winds. "It's prudent for people in those areas to prepare now for a cyclone," he said. "Prepare your emergency kit at home, have food, water, emergency stocks of any medicines and baby needs on standby." "With heavy weather around street rises will be quite strong, never drive into crossings or flooded roads." The last category two storm to hit Darwin was Cyclone Helen in 2008. It caused more than $1 million in damage and one fatality - a man who drowned after his car was swept away in a flood. /IANS