The answer to 'why is my drain frozen' is that a frozen drain is typically caused by cold temperatures causing the water in the pipes to freeze. This can happen in both indoor and outdoor drains, especially in areas that experience freezing weather. Symptoms of a frozen drain include slow or no water drainage, gurgling sounds, and potentially water backing up into the sink or tub.
The best solution for a frozen drain depends on the severity of the freeze. For a minor freeze, you may be able to thaw the pipe yourself using a heat lamp, hot water, or a drain de-icing product. However, if the freeze is more severe or the pipe has burst, it's best to call a professional plumber who can safely and effectively address the issue.