Not again! BoM issues Flood warning for Qld and NSW.

"A major rain event will engulf most of eastern Australia during the next 48 hours, prompting the Bureau of Meteorology to issue flood watches from southern Queensland to the NSW South Coast.

“Greater Sydney could be soaked by up to 200mm from late Thursday to early Saturday, potentially leading to major flooding along the Hawkesbury-Nepean River, while Brisbane and Canberra also face the prospect of heavy rain.”

https://www.abc.net.au/news/2024-04-04/torrential-rain-triggers-flood-watch-for-sydney/103665240

@sydney #sydney #NSW #Australia #ClimateChange #weather #floods

  • ephemeral_gibbon
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    8 months ago

    I’m not certain of Brisbane, but my family has a little farm about 4 hours north of Sydney. Part of it is floodplains (go under in even small floods) so we tend to be reasonably familiar with the conditions that cause the big floods.

    At the moment it’s not desperately dry, but the soil can hold a lot more water and there hasn’t been enough rain to cause run off so the dams are almost empty.

    There’s a bit of a downpour now and if it’s particularly long and intense there may be a small flood round there, but nothing like the conditions surrounding those devastating floods last year.

    Also for a lot of those rivers an occasional small flood is healthy because it helps to clear out the excess water weed that may be building up etc.

    • Zagorath
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      8 months ago

      The thing with Brisbane is that we get a big variety of different kinds of flooding, with very different characteristics. Overland flow and creek flooding can occur and be very problematic, especially in the more outer suburbs and some higher areas.

      But the most destructive kind is when the Brisbane River floods. And that happens for reasons that are impossible for someone purely looking at local conditions in Brisbane to predict. It’s a big river with a massive catchment area all the way up to Toowoomba, going south and north to the Gold and Sunshine Coast hinterlands.

      And while 2022’s floods were preceded by a lot of local rain and local conditions were extremely moist (which meant we got a lot of creek flooding and overland flow in addition to the river flooding), the 2011 flood occurred on a much drier day in Brisbane itself, thanks to the upstream weather being much worse.

      Conditions here at least seem to be drying up a lot, and I don’t think there’s much cause for concern, but back on Thursday, it’s the above facts that meant I was still a little worried even despite what it was like here.