xc 16:10 5k possible?

Based on your other times, the simple answer is yes. In fact sub 16 is possible.

6:30-45 while doable is too fast for easy days. It gains you nothing. 7-7:15 will allow you to recover.

definitely possible - if you don't over-train. 16:25 to sub 16:10 was a big mental leap for me in high school, but it's certainly doablerelax and be patient. be. patient. when i was your age, i wasn't and ran a fast time in the middle of the season and then burned out with anemia etc. because my easy days i pushed too hard (6:30 pace)my easy days in college were 7:00-7:30 and i ran 14:20's (i ran 16:02 in high school)better to be 10% undertrained than 1% over-trained.you've got it, just be patient. trust that putting in miles this summer will help you make big strides. they don't need to be fast

My top kid last year was 16:51. He had only run 10:42,4:57 the previous track season. He ramped up to where he was high 50s-low 60s for the second half of the summer last year on almost all easy running. He stayed pretty consistant in the mid to low 40s for most of the rest of the season once we started harder workouts.....so, yeah, very possible.

A couple of considerations

#1. If your state is like ours, when you start practice and early season races, it will be very hot. Even at a morning invitational, the varsity races may not go off until after noon. This will keep your times slower than you expect. Don't get impatient.

#2 Cross country courses are much slower than road courses. If you run slower than you expect in your first couple of races, that's OK, don't be impatient.

#3 training wise, if you are running 6:30 pace for much of your distance, there is not need to do "workouts" or harder, structured sessions. If you are doing harder structured sessions, you should back your easy pace down. You can't run hard sessions and fast recovery days all summer long and expect to have anything left in the tank for October and November. If you are just putting in miles, and the 6:30 pace feels comfortable, keep on rolling with it but don't be afaid to back off the pace if you feel tired. You don't need to be a workout hero now.

Read Summer of Malmo

http://www.bunnhill.com/BobHodge/rtp3.htm

and make sure you don't miss any of the pieces.

Oh, shoot. I read 16:50. 16:10 will be much more difficult. My last guy that went under 16:10 had gone 9:37 and 4:39 on the track the year before, and had hit up to 70 mpw during the summer (though he averaged about 50 for the whole time mostly due to the first 2 weeks back being really low).

Still doable. You seem to be still in a steep part of your development curve. Going from 18:16 in cross to 9:58 on the track is a huge jump.