Here is a motion sensor that detects outdoor motion to activate your lights. You can set it to welcome you or your guests home with lights. It can also keep intruders away. The Philips Hue Dusk-to-Dawn Motion Sensor has an all weather construction.
This motion sensor works with Alexa, IFTTT, Nest, SmartThings, Cortana, and HomeKit. You can easily configure it on your phone.