Also if water is approachinng, get some thick plywood , measure the distance between the brickwork on the exterior down stairs doors and get some timber cut about 3 foot high, apply a load of mastic frame sealant to faces of plywood in thick beads and along bottom edge,dont use silicone as it sets hard and is difficult to get off, screw to door frames outside of frame, this should stop the majority of ingress of water also do same for all g/f air bricks.
Pull the fuses for all ground floor sockets as if water hits them it will possibly short the whole house out.
Use plastic storage boxes to store stuff they float, so do childrens paddling pools.