RAINFALL may exceed 90mm this weekend with Sunday looming as the focus of the worst of what the Bureau of Meteorology is predicting would be very wet and windy conditions.
Much would still be dependent on the positioning of a coastal trough due to move over the region in the next two days but forecaster Lauren Pattie said most places would see falls of 10-15mm.
There was a 50% chance of receiving 30mm or more and 25% chance of falls to 90mm or greater on Sunday.
"It's looking more likely we will see heavy rain," Ms Pattie said.
"Some places could get more than 90mm depending whether or not they receive more than one (thunderstorm)."
She said there would be sunny periods Sunday with the heaviest falls localised to one or two areas but predicted falls to 30mm would be seen across the region.
On Saturday the most significant falls are expected on the northern Sunshine Coast around Noosa with heavy falls possible if thunderstorms develop.
A weak south easterly change is already being felt on the coastal border areas around Coolangatta with the coastal trough still to form but expected to move from south to north on a meandering path.
The remainder of Friday may produce a thunder storm in the hinterland later this morning after a foggy start to the day.
Winds were expected to stay light throughout with the maximum temperature to peak at 28 degrees.
Saturday would be cloudy, have a day time maximum of 25 degrees, and carries a big chance of showers and the possibility of thunderstorms in the northern regions.
If the coastal trough develops as depicted in the forecast models Sunday was expected to see the peak of the wet weather although there is a strong chance of isolated heavy falls into the next working week.
Sunday's wet weather would be accompanied by below average temperature maximums which are not expected to rise above 22 degrees.
However they are expected to climb back to closer to normal from there stabilising at 24 degrees through to at least Wednesday.
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