VANCOUVER -- The threat of flooding has prompted an expanded evacuation order for an area of central British Columbia as an impending stretch of warm weather has the potential to speed snowmelt and swell already surging waterways.

Seventy-four properties have been added to an evacuation order issued earlier Sunday by the Cariboo Regional District.

Emily Epp, spokeswoman for the regional district's emergency operations centre, said people have been told to leave about 120 properties due to flooding.

Residents were being advised to take a forest service road, or stay on their properties if access roads have already been cut by high water.

"The RCMP will be in the area (this) morning to help evacuate them by helicopter," Epp said.

The regional district news release said those residents would be airlifted to a staging point where a bus would take them to an evacuation centre in Quesnel, about 100 kilometres to the east.

In southern B.C., evacuation orders also remain in effect for 148 properties in the Okanagan-Similkameen Regional District community of Tulameen, several more north of Oliver and for about a dozen in the community of Killiney Beach on the northwest side of Okanagan Lake.

Many more evacuation alerts are posted, including one by the Regional District of Central Kootenay covering homes in the Six Mile area just north of Nelson.

Flood warnings have been issued by the River Forecast Centre for the Nazko and West Road rivers of central B.C., while flood watches are in effect for many other waterways around the Cache Creek, Merritt, Williams Lake and Quesnel areas.

Rapidly rising river levels and the likelihood of flooding in low-lying areas for the southern Interior, Boundary, Kootenay and Peace regions, prompting the River Forecast Centre to maintain high streamflow advisories in those regions

Recent rains, extremely heavy snowpacks and another round of temperatures in the mid to high 20s for many parts of southern B.C. are expected to add to flooding risks in the coming days.