October weather wildly inconsistent
IT'S a time of year that's typically characterised by sunny days, warm but mild weather and clear skies.
But so far it seems this October has been a bit out of sync.
In fact, maximum daytime temperatures have fluctuated by as much as 10 degrees in less than a week.
Ballina jumped from 21.9 to 31 degrees in seven days, Lismore from 22.6 to 32.9 degrees, Casino, 22.1 to 30.5 degrees and Byron Bay from 20.9 to 31.3 degrees.
Before Wednesday's cool change, temperatures were all well above the total monthly means.
Bureau of Meteorology senior climatologist Agata Imielska said the week of hot weather at the start of the month was the warmest since winter.
"Generally we don't see temperatures quite this warm so early in October, but it has happened in the past," she said.
"For most locations these temperatures were warmest since last year in October but these occurred much later in the month than this year."
Ms Imielska said the warm conditions were caused by a slow moving high pressure system in the Bight which directed warm northerly flow over much of the state.
"With an El Nino in full swing and the Indian Ocean now moved to reinforcing the dry and warm conditions this is likely the first of the warm conditions that are likely for this season," she said.
"El Ninos generally result in increased number of heatwaves as well as dry conditions, particularly for areas west of the Great Dividing Range."
On Wednesday, Northern Rivers residents were witness to a rare weather phenomenon where a huge wall of cloud rolled across a clear blue sky.
The little understood roll clouds, usually associated with the Gulf of Carpentaria, were spotted across the Far North Coast during a cool southerly change on Wednesday afternoon.
Temperatures from the first week of October
Ballina: 24.6, 27.2, 24.6, 27.9, 31, 30.1, 27.3. Highest monthly mean for October: 26.3
Lismore: 28.3, 29.8, 28.2, 32.9, 34.7, 33.4, 32.3. Highest monthly mean for October: 28.9
Casino: 29.2, 30.5, 28.9, 33.4, 35.6, 34.2, 34.1. Highest monthly mean for October: 30.1
Byron: 25.9, 26.6, 28.2, 29.5, 31.3, 30.2, 30.8. Highest monthly mean for October: 27
Source: Bureau of Meteorology