I saw the ISS fly right over my head one night, then disappear in the earth’s shadow. It took me a few seconds to figure out what it was, but holy crap. It’s a full magnitude brighter than Venus, according to NASA.
I have the ISS Detector app on my phone. Use it to watch the ISS pas over all the time.
You can get an app for your smartphone that will tell you when the viewing opportunities are for your specific location. You can set filters for such variables as height-above-the-horizon and brightness (the brightness varies with sun angle). The app will notify you of matching conditions and, I believe, tell you when clouds & rain will likely obscure viewing.
One of the most cool sightings of the ISS I had was 2006-7 when the shuttle had just undocked for reentry and was flying just ahead of the ISS.
Unless you knew what you were watching, just bright dots up there.