I've run the Ascent and Marathon 14 times and being a 3:50 and more to the top guy I have seen first hand that the faster runners often have no trouble at all with the weather conditions as they summit before clouds build and thunderstorms unload. This would be the 2 1/2 hour to 3:30+ types. If you are a 4 hour, 5 hour or more to the top you run the very big risk of totally adverse weather from A-Frame to the top. This can be falling temps, cloud cover which causes air temp to drop quickly, thunder, lightning, hail, sleet, corn snow (or gropple) and snow, plus heavy winds.
This year it is extremely likely the weather on Ascent day will be rotten! You can tell this by the weather in the week leading up to the race. It's been unsettled, lots of heavy thunderstorms, lots of heavy cloud cover. All of this means cold temps on Pikes Peak during the race, esp. above timeberline--25-40 degrees with wind making wind chill even worse.
Slower runners should wear tights, a long sleeve tech shirt and have a rain resistant light jacket with hood/or wear a hat to protect head (hail and corn snow/gropple on the unprotected head hurts like hell! Also bring/wear above 11,000 feet a pair of Smartwool gloves or tech gloves to keep hands warm.
Be sure to pick out a complete change of clothes and a dry pair of shoes and socks and put them in your stuff bag provided to you and drop at the start line where vans will take your gear to the top. You will be 100% happier and better off in dry warm clothes and shoes.