Rain Gear
In the mountains you will experience something we call Mountain Weather. That is where it can be flash flooding in one valley and over the ridge there are clear skies with bone dry drought conditions. Taking bad rain gear to Philmont is definitely a bad idea. Rain gear includes a rain jacket and rain pants. Although sometime people skip the rain pants, it is not recommended while you are at Philmont. Under no circumstances does a poncho count as rain gear. Rain gear needs to be something that is durable. I wish I could tell you that a great rain suit is going to be inexpensive. If you are looking for a budget friendly item, consider Frogg Toggs. They are nowhere near perfect, they offer water resistance, but they will get holes on the trail. They are not designed for extreme backpacking trips such as Philmont.