If you are living in the eastern half of NSW and through the ACT, you are currently seeing a wet start to the day and some areas have already recorded flash flooding and that is only set to increase this morning. Riverine flooding is forecast to develop up and down the east coast and there is the chance of seeing moderate flooding in some areas.
The speed of the system resolving through the coming 36hrs, may save many areas from another major flood but prepare for the worst and hope for the best in these regions.
Severe weather issues related to thunderstorm activity will continue today, tomorrow and through Saturday before the upper low begins to open up and weaken into a trough. Moisture will remain in place during Sunday and that will keep scattered showers but the rainfall coverage should be lighter.
We also have severe weather potential building for next week as well, but it is one system at a time and I will have further details on that in the coming days but do expect to see wild fluctuations in the guidance from models being hot and cold on that system. So lets focus on this feature
Rainfall Next 10 Days - State View
Rainfall is likely to be heaviest today before easing overnight along the coast as the upper low begins to weaken and shift slightly west. That will keep the thunderstorm activity in place leading to more flash flooding risks for inland areas through Saturday. Then conditions ease. The next system on the board is due in at some stage next week, could come in 2 parts. One part a weakening cloud band with a trough pushing through and then an upper low with a deep moisture supply in the east leading to widespread rain and potential for more severe weather. I have lifted rainfall totals for the short term over the Riverina, Southwest Slopes, Central West, Central Tablelands and parts of the Upper Western in response to areas of rain and thunderstorms about near the upper low.
Rainfall Next 10 Days - Southeast NSW and ACT
Heavy rainfall today about the coast, moderate rainfall inland to the Great Dividing Range will lead to some areas of flooding across the Southeast and nearby the ACT (depending on the heavy falls). Scattered showers and thunderstorms on and to the west of the Great Dividing Range with locally heavy falls and flash flooding a risk. Conditions ease during Saturday evening and Sunday should be mostly dry ahead of more rainfall next week.
Thunderstorm Forecast Thursday
Severe thunderstorms are ongoing this morning with the coverage expected to move around during the next 24 hours. Heavy rainfall and large amounts of small hail are the main issues today.
Thunderstorm Forecast Friday
Severe thunderstorms are expected to be ongoing from Thursday into Friday with heavy rainfall leading to flash flooding the main concern and the risk of large amounts of small hail will also be a low risk.
Flash Flood Risk - Thursday through Saturday
No change to the overall guidance, remain weather aware given the severe thunderstorms over the interior and the coastal areas experiencing bouts of intense rainfall throughout the afternoon and evening, possibly extending through heavily populated areas overnight into Friday before easing during Saturday
Riverine Flood Risk - Thursday through Saturday
Flooding is underway along the coastal river systems between Sydney and Ulladulla with 200mm falling thus far and another 200mm possible before conditions ease during Saturday. Major flooding is now possible through the coastal regions from Gosford through to about Batemans Bay.
Severe Weather Watch - Heavy rainfall and flooding with strong wind potential - Monday through Thursday.
Next week, additional severe weather is possible but the spread of the severe weather is very broad and encompasses multiple states with a low forming over SA. This forecast is of low confidence but should be used as a heads up for areas identified.
More information coming up this afternoon in the broader update.