Distorted scare light lens
The outside flood light, some call a scare light, when left on for many hours, gets hot enough to cause the lens to severely distort.
Please keep in mind that this light fixture was never intended to be left on for hours. If you look at the rear end of many truck trailers, you will see the same light. They use it as a "backup" light, which of course never stays on very long.
The original bulb for the scare light is an 1156, which draws 2.1 amps, which is 25 watts.
A corrective measure is to replace that bulb with an 1141. It draws 1.44 amps, which is 17.3 watts.
That will allow you to run the light for hours at a time, without causing any lens distortion. You will find that it is not quite as bright, but certainly adequate for the purpose intended.