I have found that when I have, what I call 'my bad stomach', something tragic happens. My family and friends all now believe it too and often call me and ask "are you having a bad stomach?"
It all started about 15 years ago. I woke up from a deep sleep early one morning with a really strong stomach ache. It felt like I was going to get sick, like stomach flu. I wasn't able to get out of bed for about an hour then it subsided slightly. I got up, took a shower and went about my day. I got a call about 2 hours later that my brother (my only brother that I'm very close to) was in a terrible accident. Emergency crews weren't able to get to him for about an hour. Turns out it happened at the exact time I woke up with the stomach ache. I didn't really think much about it until it happened again about a year later. Almost the exact same circumstances, my brother and this time he was in a motorcycle accident, bad stomach at the same time again.
This has continued to happen over the years. Different circumstances though. My Grandmothers passing, my mom's illness, best friends death, divorces, breakups, sicknesses. Turns out that it only happens when things happen to people I love. Family, friends, partners, etc.
I didn't tell anyone for many years; mostly because I didn't believe it myself. My brother was the one that first figured it out. He noticed it because I have a list of people I call every time I get the 'bad stomach'. He finally asked me one day, "why do you always call me right before we get bad news?" I told him about the 'bad stomach' and now he calls me and ask me if I'm having the bad stomach every time he flies somewhere.
It hasn't been wrong yet, unfortunately.