The brightness of a weatherproof outdoor nautical signal LED port light can vary depending on the specific model and specifications of the light. However, in general, these types of lights are designed to be very bright and visible in a range of weather conditions and lighting environments.
Typically, nautical signal lights will have a luminosity of several hundred to several thousand lumens. The exact brightness will depend on the specific LED technology used, the size and power of the light, and the intended purpose of the light.
It is important to note that the brightness of a signal light is not the only factor that determines its effectiveness. The color and placement of the light, as well as any additional features such as flashing or rotating patterns, are also important factors to consider when selecting a nautical signal light.