There's no surer sign of spring than this weekend's slate of half marathons.

Cook Forest Half Marathon and 5K, which starts at 11 a.m. Saturday, is a north country classic. The race features the scenery along the Clarion River on a mostly level out-and- back course. The one major hill comes at an uncomfortable 12 miles into the run.

Mom and I joke that we pack our Cook Forest race bags like we're going on a week's vacation. That's because the park and the route along the river seem to have a climate all their own.

In the event's 24-year history, runners have reveled in or endured every weather condition possible. We've had brilliant blue skies and plenty of warm sunshine, cold drizzle, blasting wind and, occasionally, a blanket of snow — and sometimes all of the weather in one race.

The USATF certified half marathon and 5K are ChampionChip timed. Competitive awards for this event include handmade pottery designed especially for the race for first place in age groups. Overall and masters winners earn a night's lodging in this Pennsylvania vacation area.

Cook Forest Half Marathon is a benefit for Clarion University's track and field and cross country teams.

Runners can register on race day, though T-shirts are available on a first-come, first- served basis.

Just a Short Run, which loops North Park Lake and begins at 8:30 a.m. Saturday, is Western Pennsylvania's most popular half marathon with more than 1,600 finishers in 2007.

The event has something for everyone. There's the traditional half marathon, which has been run since 2001. There's also a half marathon three-person relay for those wishing to sample the flavor of the longer distance run without the long training.

For those using Just a Short Run for marathon training, there's also a 30K race that starts a half mile back from the half marathon start along Pierce Mill Road.

Also, beginners and short distance speedsters might want to run the 5K event that starts with the longer races. All distances are USATF certified for accuracy.

For the fourth year in a row, Just a Short Run has been designated a Leukemia and Lymphoma Society Team in Training event. The race raises money for the cancer-fighting organization, as well as raising awareness of the disease and the fight for a cure.

And don't forget about the best perk of this event: commemorative running shorts to all preregistered runners. As the website advertises, "It's like buying a pair of running shorts and getting a race for free."

Registrations for Just a Short Run will be accepted at Elite Runners and Walkers in Robinson Township Friday or at the race staging area at North Park Boathouse on Saturday, but shorts might be in short supply then.

For information about Just a Short Run, call 412-490-0881 or email info@justashortrun.net

Friday and Wednesday, 12:15 p.m.: Lunchtime run, Cabot. Run 6 to 7 easy miles with me from St. Luke Church. 724-352-2777 or pneubert@stlukecabot.orgSaturday, 8 a.m.: Up-N-Running Group Run, Valencia. 724-898-2525 or www.runpa.comSaturday, 8 a.m.: Hot Harry's Group Run, North Park. Run from 7 to 20 miles. Leaves from Lt. Stone Field.Saturday: Fools Run 10K, Indiana. Also 3 mile walk, first leg of Indiana County Triple Crown. 724-349-0501 or jswauger@comcast.netSaturday, 8:30 a.m.: Climb Pittsburgh II, Pittsburgh. Climb 760 steps (38 floors) in Gulf Tower. 724-933-6180, Ext. 2 or ldaly@lunginfo.orgSunday, 1 p.m.: Ken Brumbaugh Memorial Race, Altoona. Choice of 5 miles, 2 miles or 2-mile walk. 814-695-4467 or contactus@hollidaysburgarea.orgApril 5: Campus Classic 5K, Schenley Plaza, Pittsburgh. Benefits Hillman Cancer Research Center. pittcampusclassic@gmail.comApril 6: Run for Someone Special 5-Mile and 2-Mile Run-Walk, Sykesville. Benefits Jefferson County Association for Retarded Citizens. 814-938-6578 or frhet@comcast.netApril 12, 8 a.m.: Run to Read 5K, Millvale. 484-894-4675 or bappitt@gmail.comApril 12, 8:30 a.m.: Martha's Run, Mount Lebanon. Choice of 10K, 2-mile or 1-mile walk to honor FBI Special Agent Martha Dixon Martinez. 412-456-2859April 19, 9 a.m.: Race for Moon and Stars 5K, McKeesport. 412-885-2537April 19, 9 a.m.: Genesis Riverside Run, Heinz Field, Pittsburgh. 412-766-2693 or tricia@genesispgh.orgApril 19, 9 a.m.: Armstrong County YMCA Big Foot Half Marathon and 5K, Kittanning. 724-545-9622 or kknepshield@yahoo.comMay 11, 8:30 a.m.: Susan G. Komen Race for the Cure 5K, Pittsburgh.www.komenpittsburgh.orgSend comments and suggestions to: 435 Cherry Valley Road, Saxonburg, Pa. 16056. Phone: 724-352-4395. E-mail: bigp16@connecttime.netPat Neubert is the running columnist for the Butler Eagle.