Flood warnings are in place with heavy rain set to lash Britons during a weekend washout.All of England and Wales is covered by yellow Met Office rain alerts lasting from Saturday afternoon to Sunday evening, though Northern Ireland and Scotland will also be damp.They warn of possible flooding, travel disruption and power cuts, with as much as 40mm of rain set to fall on already saturated ground after downpours earlier in the week.However, temperatures will hit highs of 14 to 15C, five degrees higher than average for the time of year, amid a mild spell in the country due to winds coming from the south.