Colorado Springs - Penrose Ride

Tomorrow I'm hoping to ride 70 miles to Penrose (near Pueblo)! It will be my longest ride of the year by about 20 miles. According to a book I checked out of the library (Road Biking Colorado - the statewide guide, by Michael Seeberg), I think the total elevation gain will be 4000 feet. I wanted to do some mountain riding but up there it is going to be in the 30's with 50% chance of rain/snow. Down here it should be in the 50's and only 20% chance of rain. Wish me luck!!