Thanks for the challenge! Finding apparel that can live under the umbrella of spring hail storms, summer heat waves, and brisk fall weather is certainly not easy. Which is why your key strategy is this: layers. And, because you'll be out on the trail, we're going to focus on layers that are lightweight so you don't feel like you're lugging a suitcase around when the mercury rises.
But before we start dressing you up like an onion, let's talk about fabric. Put that cotton down. Yes, it's comfortable, but once cotton is wet, it stays that way. If it's cold enough, this could result in hypothermia. So, quick-dry and moisture-wicking fabric it is. Should you get caught in a mid-summer monsoon, you won't be wet for long and, believe me, this is a bonus no matter if you're on a multi-day trail or just a few miles from the parking lot.
With these few things in mind--ultralight, quick dry, and possible chance of showers--let me run down my ideal outfit:
Lole's moisture-wicking Explore Pants ($85, lolewomen.com) are capri length--perfect for keeping you cool on hot days, but warmer than shorts should the temperature dip. Their nylon/polyester/bamboo fabric make-up will keep you dry if the skies open up and give you enough stretch to hike in them all day long without feeling restricted. Plus, a security pocket gives you a place to stash an ID, cash, and a ChapStick.
Pair those trail-ready bottoms with Patagonia's hiply designed Women's Sport Top ($49, patagonia.com). Besides its adorable, flattering shape, the nylon top--with built-in-bra--will wick away sweat and give you enough support for a day-long hike. This has become my new favorite sport top--it accompanies me to yoga, on hikes, and runs.
A long sleeve is going to be an easy layer to throw on or in your pack without taking up too much room. I suggest Icebreaker's Merino wool Chase Zip ($85, icebreaker.com), with strategically-placed panels of mesh for venting. The wool will ward of stink and sweat while keeping you warm, and the quarter-length zip creates an extra way to ventilate your upper body.
Sierra Designs is known for making bombproof but ultralight shells that won't let a drop in. My favorite is their Isotope Nano Jacket ($99, sierradesigns.com). It scrunches down to the size of an apple, it breathes in steamy-but-damp climates, and it's so lightweight, your pack won't even notice its presence. And, you definitely get bang for your buck: It comes with an MP3 player holder and folds down into its own pocket to keep it compact.
Finally, throw it all in REI's Flash 18 ($29.50, rei.com). This minimalist pack has just enough room for a shell, a couple layers, lunch, and a hydration reservoir but feels lighter than it looks (hard to believe). The fabric? Waterproof. A simple drawstring pulls it closed on top and keeps out rain thanks to a protective flap.
Alicia Carr, assistant managing editor of Outside and managing editor of Outside's Buyer's Guide, is a guest columnist for Gear Girl.