APRS Coverage
Don't know
Voice Cellular Coverage
Good, very usable
Data Cellular Coverage
Good, very usable
Cellular Provider
AT&T

I won't give all the details of how to get to Red Top, etc. This summit has been well covered by others. Here is an interesting report from K7MAS for comparison:

http://www.pnwsota.org/blog/k7mas/2015-march-09/sota-activation-red-top-mountain-kittitas-county-washington-march-8-2015

WW7D and I went up to Red Top on March 30th, 2019. There is still MANY feet of snow up there, and all of the roads are still closed. The trip that Mark and Tim did back in 2015 will not be possible for several more weeks at least!

Darryl and I departed Lake Forest Park with snowmobiles in tow early on Saturday morning. We had no intel on snow conditions and were not positive that there would be enough snow on the FS road to ride up there. Turned out there was a LOT of snow, with just a few small bare patches right at the start.

We had a pleasent ride up to the parking lot, where we left the snow machines and donned our snow shoes. It was a glorius day with great 360 degree views as we made short work of the hike up to the summit.

Once on top we deployed my 20/30 linked dipole and Darryl jumped on 2m FM. We made a bunch of contacts including a S2S on 20m SSB with KG6HQ on W6/CT-256. We also had a 20m CW S2S with KR7RK W7A/PE-002.

The trip back down went quickly and we were soon on our way to our 2nd summit (Hicks Butte).