Seacoast Half Marathon
Race Day Weather
Comfortable temps, moderate wind
Mild 51°F temps at gun time mean comfortable early miles without overheating risk. Moderate winds around 15mph may affect pacing on open sections of the course. Moderate humidity at 74% is worth noting for effort level, especially in later miles.
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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.
