The ACT has recorded its wettest October in 88 years, with the region receiving rainfall in excess of three times the average across the month.
According to the Bureau of Meteorology (BOM), Canberra recorded 166mm of rain in October.
The capital's normal monthly average for that month is usually about 50mm.
Five sites around Canberra broke records for the most rainfall in a single October day.
Aranda recorded 65 millimetres on October 22, breaking a 52-year record, while Bruce recorded 48.6mm on October 24, breaking a 41-year record.
BOM senior meteorologist Dean Narramore said it was the wettest October since records began.
"It rained for 19 of the 31 days of the month. It felt wet, and it was," he said.
Mr Narramore said the wet weather was caused by a "very active weather pattern".
"We had all these low-pressure systems moving through every three or four days, and they were tapping into lots of tropical moisture that was available across northern and eastern Australia," he said.
"These lows were cut off lows, and very slow moving, so it allowed for it to rain for a long time so each time it did rain we saw substantial falls of 30 to 50mm."
The heavy rainfall saw many rural areas just outside Canberra experience flooding, including Yass, Cooma and Gundaroo.
Colder days, warmer nights
The heavy rain also caused the temperature to deviate from the norm, with colder-than-average days and warmer-than-average nights.
The ACT normally averages around 21C in October, but that dropped by three degrees down to 18C.
Mr Narramore said the change in average temperature could be explained by the record-breaking rain.
"In these kinds of wet patterns you have the warmer-than-average nights … and you have the cooler-than-average days because there is no sun," he said.
"The cooler days were because it was usually cloudy, it was rainy for many of those days.
"In the night time it was also cloudy and rainy so we didn't get those frosts or those really cold nights."
November 'not looking to the extremes'
November has already seen some rain in the capital, but Mr Narramore said it is unlikely to be as wet as October.
"We've already seen some storms around the area [this week], we've got two storms in the coming days as well and our next big weather event could be on the weekend when we're going to see another band of widespread rain and thunderstorms," he said.
"To get two back-to-back records is pretty up there, but we're still looking at probably an average to above average month once again.
"We're looking at probably another month of warmer than average minimums, average to maybe slightly below average maximums, and probably above average rainfall again for November, but not looking to the extremes we saw in October."
