Jasper National Park, which attracts more than two million tourists annually, was evacuated overnight and early on Tuesday along with the town. Officials said there were up to 15,000 visitors in the park at that time.
Video posted on social media showed a long line of cars slowly driving out of Jasper. Evacuee Stephanie Goertz told the Canadian Broadcasting Corporation that it had taken her three hours to drive three km (1.9 miles).
There are 170 wildfires burning in Alberta and a further 375 in neighboring British Columbia. Around 275 are classified as out of control and officials have warned the situation could worsen.
Christie Tucker, Information Manager at Alberta Wildfire, said firefighters across the province were preparing for challenging conditions on Tuesday as a cold front moves in from the west and winds shift.
"This will change the intensity of several of the wildfires in Alberta as well as the direction they may be moving," she told a news conference, adding there were extra firefighters and aircraft on standby to help in Jasper, if needed.
Alberta Public Safety Minister Mike Ellis said the wildfire was approximately 12 km south of Jasper on both sides of the river.
The evacuation order was issued late on Monday and people were told to head west into British Columbia because the fires were threatening roads heading south towards Calgary, Alberta. Officials said the evacuation was progressing well.
Scorching heat in the Northern Hemisphere has baked much of the Western U.S. and Canada since the start of July. Thousands have already had to evacuate their homes in Alberta and British Columbia.
Wildfires are also burning near the key oil sands hub of Fort McMurray in northern Alberta. The oil sands region produces around two-thirds of Canada s 5 million barrels per day of production.
Earlier this month Suncor, Canada s second-largest oil company, temporarily curtailed some production and evacuated non-essential workers from its 215,000 barrels-per-day (bpd) Firebag site because of a nearby fire.
One of the only two highways out of Fort McMurray was closed due to wildfires on Tuesday, while the Alberta government warned the other could close at short notice due to a blaze nearby.
In April, federal officials said Canada risked another "catastrophic" wildfire season amid higher-than-normal spring and summer temperatures across much of the country.
Last year Canada endured its worst-ever fire season, with more than 6,600 blazes burning 15 million hectares (37 million acres), an area roughly seven times the annual average.
