A friendly heads-up from people who live in Michigan: any given day can start with fog, sunny by noon, detour through a mid-afternoon squall, and end with a sunset so good you'll forgive the whole middle part. Dressing in and packing layers is not optional — they're a UP survival strategy. Pack 'em, wear 'em, and thank yourself later. And in case you realize upon arriving that you forgot something, several of the most needed items are available in our retail shop (indicated by * on the lists).
 

Being on or near the water, our region also runs 10–15° cooler than downstate or inland locations. What feels like a perfect t-shirt day in Grand Rapids might call for a fleece quarter-zip here. My mother-in-law is, to this day, surprised by this coastal tempering whenever she visits and regrets not packing her favorite sweater for the umpteenth time.
 

The universal packing list, regardless of what you're doing:

 

A positive attitude

genuinely appreciated
 

Water

a water bottle* and drinking water* 
(we will refill any water bottles with reverse-osmosis filtered water at the shop)
 

Your Medications

if you have a life-threatening allergy or any medical condition, bring what you need and let your guide and other members of your group know where it is. Protect from the elements using a zip-top plastic bag. 
FYI: All our PFDs have pockets so medications stay easily accessible on the water.
 

Layers

synthetic fabrics dry fast and keep you warmer when wet. Cotton dries at the speed of a Michigan road construction project and you'll get chilled even on a hot day. Leave the new Pink Pony cotton hoodie in the car.
 

Sleeves (any length)

going without a shirt or sleeveless can create friction hot spots between your body and your PFD or daypack. And if you're biking, you won't discover your back is the color of a stop sign until your shirt hurts at the ice cream shop (peanut butter Mackinac Island fudge is my favorite BTW).
 

Sunscreen*

reapply. Then reapply again.