Update 8/4-8?13 JMT
Snow 50 feet long on steep north side of Glenn was treacherous in morning when still hard, otherwise caution rest of day.
Of larger concern, south side of Mather Pass had a 100 foot very steep ice hard in morning, small foot steps with little horizontal purchase section about 1/6th of the way up. Going down and around through the boulder field would be possible but difficult enough that many hikers would attempt the crossing. The fall would be serious and potentially fatal. A number of thru-hikers were seen in very thin trail shoes and even hkining in sandals, making this crossing more treacherous.
The water crossings from Mather through Evolution valley were very difficult especially given how late int he year it is. Care needs be taken.
As always, the official trail conditions site is not accurate so take care.