Otter Lake rose another 12 inches (30 centimeters) this morning because of Thursday night's light rain and cooler temperatures.
Another seven houses have been affected, bringing the total to 81 out of 272 houses that have been flooded are nearly flooded.
All residents should be prepared to leave on very short notice if an order is given, the Regional District of Okanagan Similkameen said. Valuables and important documents should be removed when leaving.
A registration centre is still open in Princeton. Residents are asked to check in with the fire hall prior to leaving the area.
The lake rose three feet Wednesday evening due to heavy rain.