Porter, a first-year Class-Two athlete, cleared the high jump bar at 1.80 metres for the day's first record.
Porter, who described her performance as "great", said it's just the beginning of what is to come this season.
Peta-Gaye Reid of St Elizabeth Technical and Edwin Allen's Kimberly Williamson, who both represented Jamaica at last year's World Youth Championship, cleared 1.75m for second and third, respectively.
Kavian Smith of Jamaica College was also impressive, running 10.27 seconds to capture the boys' Class- One 100m.
Manchester High's Leslie-Ann Mitchell won the girls' Class-One 100m in 11.56 ahead of Holmwood's Yanique Ellington (11.67).
Edwin Allen's Tracey sisters, Ristananna (2:19.47) and Nikita (2:24.59), were first and second in the Class-One 800m events.
Trishana Griffiths of Glengoffe won the girls' Class-Two 800m in 2:26.97.