Weird noise in Germany

Anyone know what this sound is? I heard it while waiting for a friend to open her door and let me in. We were staying near some forests and it was a bit foggy, around 6:15pm. This is in Germany, around 15 minutes away from Weinheim. The audio is quite hard to hear but it was like some kind of howl or wail? I really have no idea. It kept repeating but I only managed to catch it once on my phone before my friend came and let me in.