Shooting outdoors? Start with the shots you want most.
We live in Ohio. That means all kinds of weather. I’ve shot in rain, snow, and oppressive heat. One thing I’ve learned (the hard way) is that however good your intentions are when you’re preparing a shoot, you’ll likely not get all the shots you want. Start with the location and the pictures that you’re most excited about. That way, when your subject’s makeup is melting off of her face, you’re soaked to the bone, or he’s shivering uncontrollably, the shots you leave with when you throw in the towel are the better ones anyhow.
And it doesn’t hurt to have a super-collapsable umbrella in your gear bag. They don’t take up much space, and are indispensable in keeping your models, you, or someone else dry until the rain lets up. If there’s a small chance of it being cold out, keep a pair of gloves in your bag. So handy (pun intended—sorry).