Squaw Valley, Alpine Meadows and Sugar Bowl ski areas were all open on the July 4th weekend. However, the snow is melting fast. What's left is packed down so you don't need snowshoes or gaiters for the snow. (Some people like gaiters in the summer to keep debris out of their boots.)

Weather note:
AccuWeather says the high today is 79
http://www.accuweather.com/en/us/norden-ca/95724/weather-forecast/2167268

The Weather Channel says it's 72
www.weather.com/weather/today/Norden+CA+USCA0773
Sugar Bowl says it's 73
www.sugarbowl.com/4305

The solar radiation at 8,000 ft elevation is almost 50% higher than at sea level. (The air is 25% thinner and the sun is passing thru less of it). Reflection off of snow will intensify it even more. That plus the dry air makes you more prone to sunburn.
The forest is not as dense as in other parts of the country, so you will be in the sun more.

Francy's equipment list has several sun related items:

Sun hat with a full brim - ie. not a baseball hat. You need protection for your ears and neck.

Sunglasses - A Light Transmission Factor (LTF) of 9-15% with 99.5-100% UV blocking is best.

I just went to the mall and visited 4 stores selling sunglasses, Sunglass Hut, LensCrafters, Oakley and Optical World. Oakley was the only one who could tell me the LTF. The manufacturer web sites were not much better and I couldn't find anything at Consumer Reports or Backpacker Magazine either. Sunglass marketing is very heavy on glitz (pictures of beautiful people and web sites with fancy animations), but light on facts. My web site also has some examples of lenses with different LTF's you can use as a guide.
  REI lists LTF under Specs for their sunglasses.
  Photochromic or Transition lenses which lighten or darken in response to the sunlight intensity are popular with hikers. Unfortunately they do not get dark enough in warm weather and they are slow to change.

See donsnotes.com/products/sunglasses.html

Sunscreen - Broad spectrum (UVA & UVB) SPF 30 - 50.
  SPF 15 blocks 93% of UVB rays
  SPF 30 blocks 97% of the UVB rays
  SPF 50 blocks 98% of the UVB rays
  Anything higher doesn't do much but cost you more. 
  (SPF only measures UVB)