Residents in the local community raised the alert on social media by sharing photographs of the rising water levels.
They advised people who have cars parked in the free Wetherby Leisure Centre car park and Wilderness car park to move immediately.
Cars have already been partly submerged by the flood water.
Levels in the nearby River Wharfe are expected to peak between Saturday afternoon and evening.
A flood alert is in place for the Lower River Wharfe at Wetherby.
This means flooding is possible and residents should be prepared for flooding.
The Enviuroment Agency said: "This flood alert remains in force. Levels have receded to normal levels in the Upper Wharfe Catchment but remain high in the Lower Wharfe Catchment around Collingham and Wetherby where we expect the levels to peak Saturday afternoon and evening.
"Please avoid using low-lying roads and footpaths close to watercourses as river levels can rise quickly with little warning."