Well I have verizon and cell coverage is spotty at best from half way up the portal road to the summit.I have gotten calls out from the portal but only intermittantly and could never get a call out from anywhere I tried on the MW main trail or summit.I wouldn't count on getting a message out to reassure a family member. Best bet is to let them know if they don't hear from you it doen't mean you are in trouble just unable to get cell phone service.
I know some people say they have been able to use their cell at certain places on the mountain.My buddy and I couldn't use our phones anywhere past Lone Pine.
