Rain Jacket and Trousers vs Poncho.
Rain Jackets (shells) Rain jackets have been developed for outdoor activities and can provide an outer soft “shell” worn over our clothes. For rainy weather I like the soft shell rain jacket with a hood and waterproof trousers as they are functional and versatile. I can wear a high-tech lightweight jacket not only for rain but also to keep me warm and when it is windy. My high tech Rab jacket is wonderful, though bulky and heavy at 700 grams. I use it frequently during winter and on day walks for both the waterproofing and warmth. Without doubt it is my favourite jacket, despite the weight. There are many brands and styles available and I also have lighter ones for warmer weather. Suggest looking for soft shell types with a hood and if you can afford it with zips under the arm pits to allow heat to escape.
TIP. try and have a jacket that is long enough at the back so when you sit down you are sitting on the outer shell not a wet surface.
Ponchos have the advantage of completely covering your clothes and backpack and, if long enough, keep rainwater clear of leggings. I think in really heavy rain they are unequalled. The drawbacks, however, are that good quality ones are bulky, heavy (range from 350 to 500 grams), and don’t have the versatility of having a separate rain jacket and trousers .They are also difficult to put on by yourself. Disposable ones are an option but usually not designed to also fit over a backpack. High winds can cause havoc as the poncho lifts up. So, look at the likely weather conditions and prepare yourself for the time of the year when you are doing the long walk.
TIP. The really cheap ones are not suitable. Look for one with a hood and space for the backpack otherwise they simply will not cover you.
Rain pants.The rain pants I prefer are lightweight ones purchased from REI . They have side pockets that can be closed with zips as well as zips on the bottom of the legs to make it easier to put them on. There is also a cord that can go under the boot to keep the pants secure. My rain pants have a drawstring waist-band. I would prefer if there were some loops for a belt; however, they are lightweight, comfortable, and relatively inexpensive. They can be worn as trousers over underwear when it looks like rain and the weather is warm. My wife has similar rain pants for women. Lots to choose from.
TIP. Look for rain pants that are lightweight and breathable. (not ski or snow pants)
Waterproof Gloves. If your hands get very cold like mine then most gloves suitable for trekking don’t both keep my hands warm as well as are waterproof. I am not thinking of ski gloves because of the bulk and weight although if you have them they will work but not sure how they would go with walking poles. Give them a try. I have looked in the the USA and Australia for waterproof gloves without success. So far the only brand I have been able to find is one sold in the UK called Sealskins. Check them out at the link below.