What is the average weight for 19 yr old girl 5"3?

Range. To keep the bmi (body/mass index) between 20 - 25, the weight interval could best be 113lbs. - 140 lbs. Underweight is < 104 lbs. Overweight is 142 - 169 lbs. Obesity class i: 170 - 198 lbs. Your activity and body type play a role in the ideal weight determination, that's why there's an interval. Your doctor can help you determine if your weight, height, activity, and body type are healthy.
See chart. You can look at the image and find your healthy bmi range corresponding to your height. This is an estimate as different people have vary amounts of muscle mass, etc. But this can give you an idea of a good range for a healthy weight.