Its 33 degrees outside and sometimes in my house its even hotter. In the back of my house, we get the wonderful mountain breeze but where I am located I get nada. I don't have ac so I use a fan but that doesn't change how the heat affects my makeup. I was trying out a lipstick on my friend on Saturday, brand new shade that I don't normally use and it broke and went all mushy when I pushed it out of the tube. So I drew a conclusion that it must be the heat . I normally store my makeup in my makeup organizer which is made out of wool or yarn or some fabric like that so it doesnt keep the products too hot ( 4 drawers for everything) plus some random baskets my mom got me and this doesn't seem to prevent them from being affected by the heat so I did some research on how to prevent " MAKEUP MELTDOWN).
1. Nail Polish
Nail polish tends to get clumpy and thick if its damaged by the heat. You can remedy that with a nail polish thinner but prevention is better than cure. Try storing your nail polish in the fridge( I learnt this from my friend Tiffany while going into her fridge one day to discover nail polishes next to the drinks) She said it helps them stay cool in this crazy heat and prevents them from getting to thick. However you can just make show you store them at room temperature, not too hot or not too cold.
Very easy to melt from heat. I don't recommend storing them in the fridge but store at room temperature and keep away from extreme heat. Also throw out the damaged lipsticks. They won't be the same texture or shimmer or colour after they've been damaged. Remember to check the expiry date also. Lipsticks can last up to 1 year. As a rule due to the formulations, lipsticks can dry out and become more brittle. Those comprised with silicone oils may last longer. Opened, all formulas....4-9 months.
3. Liquid Foundation
Have you ever seen how your liquid foundation separates with water and oil on top? Well that can be a result of the heat. I know people who store their liquid foundations in the fridge to keep them from separating but you can also store them at room temperature. Store in a cool, dark, humidity controlled place in airtight containers for optimum freshness and efficacy. Liquid Foundation can last up to 6 months once opened.
Here's more on cleaning out your makeup drawer http://sterlingminerals.blogspot.com/2010/03/spring-clean-our-makeup-drawers-and.html.