Obviously fireworks are the biggest safety hazard. And you've gotta wear lots of sunblock if you're outside all day.  But here are four hidden hazards to think about this weekend:

1. Dehydration. Some of the early signs are dizziness, fatigue, and nausea.  So drink more water than normal.  And catch some shade every now and then.  Also, alcohol suppresses a hormone that helps you retain water. It stimulates your bladder and makes you pee more.

2. Ingredient-induced burns. Also called phytophotodermatitis. Bless you. Lime juice on your hands reacts with sunlight, and can cause bad blisters that won't show up for a day or two.  It can also happen with mangoes, carrots, and parsley.

3. Food poisoning. Stuff that's refrigerated shouldn't be left out for more than two hours.  It's been hot lately, and will still be and humid in Iowa over the 4th, and this weekend, and that adds to the risk of food left out.. Keeping stuff like raw meat in a cooler with ice is a good idea. And also make sure nothing's too undercooked.

4. Heatstroke. If you feel nauseous, have a headache, or get cramps, it's time to find some A/C, drink water, and maybe take a cold shower. If you're confused, can't walk, or have trouble breathing, it's more serious. Call 911, or go to the E.R.