Cover up your potted plants and bring the dogs inside tonight; the National Weather Service in Birmingham has issued a Freeze Warning in effect for the northern half of central Alabama.Temperatures are expected to fall to approximately 27-31 degrees in the early morning areas and remain below freezing for several hours. The National Weather Service advises that sustained temps of less than 32 degrees Fahrenheit can drastically affect sensitive vegetation; precautions need to be taken to protect these plants overnight and into the morning hours. If you have any "outdoor" pets such as dogs or cats, you should be sure that those animals have a way of keeping warm as well.