Seacoast Half Marathon
Race Day Weather
Cold start, gradual warm-up
Runners will face a steady temperature rise from 32°F at the start to 45°F at the finish. Wind will be light, not affecting performance. With humidity at 54%, conditions are favorable. A conservative pace is recommended to adapt to the temperature increase throughout the race.
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Race Info
The Seacoast Half Marathon is an annual charity half marathon in Portsmouth, New Hampshire, first held in November 2006. It starts and finishes at Portsmouth High School and runs through Portsmouth, Rye, and New Castle along the seacoast. The race is run entirely by volunteers, and net proceeds go to a different local nonprofit beneficiary each year. The 2026 edition, its 20th, is scheduled for October 25 with net proceeds benefiting the Krempels Brain Injury Center.
