Chances are, you're planning on using the same skin-care products this summer that you used this past winter. But what you may not know is that skin care is seasonal. "Skin is prone to dryness during the winter -- and oiliness during the summer," explains dermatologist David Sire, M.D., director of Advanced Laser and Dermatology in Fullerton, Calif. So you need to revamp your routine accordingly. Here's how:

Try a toner. While you can use the same cleanser year round, come summer you'll get a little extra cleansing with toners that help remove excess oils. (You can use them instead of a cleanser in the morning, after cleansing in the evening or even during the day to freshen up.) "Use a toner that contains an oil solvent (like alcohol or witch hazel) during the summer," Sire says. (Women with rosacea or eczema should steer clear of toners, which can aggravate their condition.) Best bets: Olay Refreshing Toner ($3.59; 800-285-5170) and Origins United State Balancing Tonic ($16;

Use a clay- or mud-based mask. If you typically use hydrating masks, you may want to switch to a mud- or clay-based mask. (You can use it up to three times a week.) "Mud and clay are absorbent, helping to draw oil and impurities out of the skin, unclogging pores," Sire explains. Good ones to try: Elizabeth Arden Deep Cleansing Mask ($15; or Estee Lauder So Clean ($19.50;

Switch your moisturizer -- or skip one altogether. "While your skin needs thicker, more emollient (more moisturizing) creams during the harsh, drying months of winter, it needs lighter lotions during the hot days of summer," says Lydia Evans, M.D., a dermatologist in Chappaqua, N.Y. If you have oily skin, you can probably skip a moisturizer altogether during the summer months. Helpful tips: Look for lotions with a more liquid formula. "Trust your fingertips," Evans adds. "Before you apply a moisturizer, feel it. If it feels heavy, pass it up. If it absorbs quickly, then it's the one you will want to use." Try L'Oreal Hydra Fresh Moisturizer ($9; or Chanel Precision Hydramax Oil-Free Hydrating Gel ($40;

Always apply a sunscreen. If you didn't use a sunscreen every day during the winter, you should during the summer. "It should have a minimum SPF of 15," Evans says. And, instead of using thicker, creamier sunscreens, look for lighter spray formulations or gel- or alcohol-based products that won't leave a greasy sheen on your face. Try DDF Sun Gel SPF 30 ($21; or Clinique Oil-Free Sunblock Spray ($12.50; If you need a moisturizer (see previous tip), save a step and use a moisturizer with SPF. Just remember to reapply it regularly if you're out in the sun.