Rain will plague parts of eastern Australia during the next two days, with some areas likely to experience flooding. A low pressure trough hugging the east coast will produce rain and thunderstorms during the first half of this week. Rainfall will be enhanced in some areas by low pressure systems embedded within the trough. The presence of these lows makes it difficult to know exactly where and how much rain will fall during the next couple of days. At this stage, most computer models indicate that 50-100mm is likely to fall along the southern coastline of NSW between about Narooma and Kiama during the next 48 hours. Isolated heavier totals are possible in this region, which could produce localised flash flooding during Monday and Tuesday. Falls should be lighter north of Wollongong although there is still potential for heavy rain and thunderstorms along the coast and ranges all the way up to central Queensland today. The northern section of the trough is likely to trigger intense thunderstorms over Queensland's central inland during Monday, where large hail, damaging winds and heavy rainfall are all possible. A flood watch was issued for coastal catchments between Sarina and Brisbane on Monday morning. Some rainfall will spread into eastern Victoria during the next three days, with falls of 20-30mm expected in parts of the East Gippsland District. Rainfall totals should be lower over flood-weary catchments further west. Some parts of Victoria are still recovering after record-breaking rain inundated some inland river catchments at the end of last week. Between last Friday and 9am today, some rain gauges in Victoria collected more than 200mm of rain. This included 245mm at Mount Saint Leonard and 221mm at Mt Wombat. Echuca's 139mm during the last three days was close to five times their monthly average for this time of year.