Weeping Wall is a name given to volcanic crater known as Waialeale Mountain, where "Waialeale" means “rippling water”. The mountain is the second highest point on the island of Kauai, and is known to be the second wettest area found on Earth.
Hardly ever does Waialeale see clear sky above,—heavy mists are there year-round, except only 20 sunny days a year. Maybe that's where tears come from. But seriously, the place is stunning, and mist only contributes to the mysterious atmosphere in this extremely green, and extremely humid oasis.
If you are willing to hike there, prepare to get really wet, as you'll have to cross a range of rivers. But the best way to observe waterfalls is from the seat of a helicopter, and not only because of better visibility, but also for the sake of your safety.
The area is not safe to roam around on your own because of frequent flash floods. There always will be some adventurous extremals determined to explore the site on foot, and it's cool no doubt. However, sometimes such an adventure turns out not funny. Owing to flash floods, hikers often get stranded and can be rescued by helicopters only. But even relying on that help is insecure, as cell phone reception is rather chancy in the basin.
Taking all that into consideration, we recommend booking a tour rather than venture in the floods. However, stubborn ones may be even encouraged by these warnings. Anyway, be careful.
High season is summer time, but also the third week of November around Thanksgiving Day, and Christmas season. Although, Mount Waialeale seems to be crying all year non-stop.