Two rares in Dragonflight, the Trial of Elements and Trial of Flood, are weekly events which award a guaranteed piece of gear that can drop at a very high item level!
Item Level of Drops
Like other rares and gear sources from Open World content, the item level of the gear that drops will scale based on your item level. It looks to drop around +10 of your average item level and can scale higher than Mythic 0 item level.