Seacoast Half Marathon
Race Day Weather
Cool start, steady wind
Runners will face temperatures starting at 51°F and gradually rising to 54°F. Winds from the WNW at 15 mph may create a headwind effect, particularly in exposed areas. With humidity at 74%, it’s advisable to start conservatively and stay hydrated throughout the race. A light layer may be beneficial during the pre-race wait.
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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.
