I was there June 9-10 in 2008. We hiked half way to trail camp in short sleeves and added jackets later. At Trail Camp, when the sun went down, the temperature dropped. Was below freezing and very windy. The next morning we hiked the rest of the way to the summit. I had on 3 layers (top and bottom) and was just right. Make sure you have a hooded outer shell. I would've frozen without it. The wind was ferocious. Skies were very clear and it was pretty cold.
There was a little snow above Trail Camp. We actually used our crampons and ice axes to ascend the chute between Trail Camp and Trail Crest. (Lots of snow in the chute) The switchbacks were frozen over with ice early in the morning but thawed out by noon.
Be ready for anything!
