The anniversary of the 2003 bushfires on Wednesday was likely to evoke many memories of that deadly day, with one large fire continued to engulf thousands of hectares of land to the east of Canberra and another near Sutton was near homes.

Such was the case for ACT Policing's Sergeant Jeff Knight.

"I'll never forget that day - the smoke, the flames and the suffocating heat," he said on a post on the ACT Policing's facebook page.

"But it is the memory of the despair on those residents' faces as they realised they had to leave their homes, potentially forever, that lingers."

Wednesday's fire would have also felt like de ja vu for Bungendore residents who were defending their homes on Hazeldell Road, the same road that was blackened by a blaze four years ago.

Bureau of Meteorology forecaster Ashleigh Lange said weather conditions were similar on these occasions - each forming perfectly for fires.

"Low humidity, high temperatures and strong winds make for a high chance of fire," she said.

"On Wednesday, we had humidity drop to 10 per cent, temperatures reach 36.5 degrees and winds of between 25 and 40 kilometres an hour with peak gusts of up to 50 kilometres an hour."

These factors, combined with fuel load and fuel moisture, help determine whether a bushfire will occur. The greater the fuel load, the hotter and more intense the fire.

"A trough moving over Canberra has brought the storm winds, warm northerly dusty winds and high temperatures, which helped bring danger for fire this week," she said.

"These troughs are more likely during summer when it is hot and dry, but it's hard to say if it's more so at this particular time of the season."