This circuit shoots rockets at regular intervals at night or during rain/thunderstorms.

The special effect actually consists of a simple red tone circuit and a lot of fireworks. The special thing is the daylight detector: It is set so that from evening to morning and in case of rain or thunderstorm a red tone signal is emitted. This signal is transmitted to a clock which is coupled with a dispenser. This means that in the dark a firework rocket is fired at regular intervals.
The best way to install this circuit is in a lighthouse. If you extend the signal that goes to the dispenser so:

And then puts it up to the roof of the tower, the fireworks explode after the expiration of the flight time under the roof, thus on the top of the lighthouse and becomes so a warning signal for wandering sailors.

Instructions:

On the screenshot at the top you can see everything that is important to build the system. In addition, however, you should note that the distance from the daylight detector to the first amplifier accurate 9 blocks, otherwise the warning signal will still be present even in the middle of the day and the signal Sync and corrections by n17t01 must be inverted.

However, this is not suitable for survival mode due to the high rocket consumption, unless you cheat, or spend your entire Minecraft existence just crafting rockets.
If you don't want missiles launched that frequently, you can also use a Long-term clock which, for example, only triggers every 15 minutes.