ONE of the most constantly asked questions during the ongoing flood crisis in Lismore is why the Northern Rivers continues to get saturated with heavy downfalls.
The floods at the end of February were mostly from a single, extended rainfall event while in 2017 it was heavy rain as ex-Tropical Cyclone Debbie moved south.
Bureau of Meteorology duty meteorologist Helen Reid said there are a number of factors to consider.
"This year we haven't had tropical cyclones on the Queensland coast, instead we've had these broader features and troughs moving a little bit further south," she said.
"It's still been able to bring all the moisture in from the tropics with it and it comes far enough along to interact in the upper atmosphere with what comes from further south.
"That combination is enhanced by what's happening in the upper atmosphere and that just seems to be the pattern for this season.
"The devastation from tropical cyclones is usually in quite a narrow band, whereas these flooding situations are across a much bigger area and don't have that same focal point."
Reid said current warnings remain in place with the band of rainfall expected to continue throughout the day with rivers continuing to rise, causing risk of flash flooding around the region.
"It's still very wet, but at this stage it looks like the heavier rainfall is to the south," she said.
"There's been over 250mm through that northern part of New South Wales to 9am this morning.
"The rivers are on the rise, even if there is a bit of a lull in the rainfall over the next few hours, all the warnings are still in place.
"There is still room for another 50-60mm to come in tomorrow."
Further rainfall is forecast for the remainder of today and Wednesday.
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