(AP) -- The launch of five suborbital rockets from Virginia's coast is being rescheduled again.

NASA had planned to the rockets early Friday, following several earlier postponements due to bad weather. at three viewing sites in Virginia, New Jersey and North Carolina forced the agency to postpone the launch. The launch requires clear skies.

says it will decide Friday afternoon whether to attempt the launch Sunday morning.

The rockets are part of a study of the jet stream. They will release a chemical tracer from white clouds that will allow scientists and the public to visualize the winds.

Residents from South Carolina to southern New Hampshire and Vermont might be able to see the clouds for up to 20 minutes.