The forecast of strong winds blowing through Cape Canaveral on Friday has forced officials to forego making an attempt to launch the inaugural Boeing Delta 4-Heavy rocket on its demonstration flight.

"We are very concerned about winds for tomorrow," weather officer Kathy Winters said.

"The weather just doesn't look like it's the right situation for us. So we are going to make our attempt on Saturday," said Dan Collins, the Boeing vice president of expendable launch systems.

Saturday's available launch window extends from 2:31 to 5:27 p.m. EST (1931-2227 GMT) for liftoff from pad 37B.

Air Force meteorologists were predicting a 70 percent chance of bad weather for Friday's launch opportunity because of a cold front sliding into Central Florida, bringing clouds, showers, high winds and possibly even some thunderstorms.

"At the conclusion of our Launch Readiness Review this morning, the leadership from the Delta 4 program, the U.S. Air Force's EELV program and the leadership of the Range and (45th Space) Wing got together and looked at the weather and the predicted winds for early tomorrow. The winds are predicted to be high and a very high probability of exceeding our (rules)," Collins told the pre-launch news conference today.

"Therefore, we have made the decision that it would not be prudent to subject the vehicle to the possibility of damage tomorrow. So we are waiving off of an attempt Friday and putting our attention and focus on a Saturday launch."

Although a break in the storms might have occurred during the nearly-three-hour launch window Friday, Winters said the winds would have persisted throughout the day. The winds were also a major concern for rolling back the mobile service tower and the rocket sitting exposed on the pad in the hours leading up to liftoff time.

The weather forecast for Saturday is slightly better with a 60 percent chance of unacceptable conditions due to clouds and wind. Sunday offers the best weather with only a 20 percent chance of winds violating the rules.