Carl Lewis took advantage of a strong following wind to execute the second-best long jump in history, 28 feet 7 3/4 inches, tonight at the 93rd U.S. Track and Field Championships.

Only Bob Beamon, with his world record 29-2 1/2 at Mexico City in 1968, has leaped farther. Although the wind nullified Lewis' jump for record purposes, he jumped for joy and bounced around the track in front of the stands as he and the crowd celebrated the main event of a long first day of competition.

"I thought it was the high 27s," Lewis said."It felt so comfortable, I didn't think it could be that far. I feel I'm a ways from being perfect and I didn't expect to jump that. I'm inching closer to 29, so who knows?"

Lewis' jump came on his second qualifying attempt, after he had fouled on his first. He was entitled to one more try, but passed.

"I think I'll take that one," said the 6-foot-2, 175-pound University of Houston sophomore, who will turn 20 on July 1. "It's windy and if I jumped 30 feet it wouldn't make any difference."

The long-jump final, originally set for Saturday at 3 P.M. (PDT), has been reset for 6:30, which means a busy day for Lewis. He is also scheduled to compete in the 100-meter semifinals at 5:30 and the 100-meter final at 7:20 as he attempts to match his NCAA double.

"I'd rather have jumped at any time than 6:30, but if I didn't think I could do it, I wouldn't try it," Lewis said. "It puts all the events closer together and makes it a little harder."

Steve Scott, who trains in Tempe, Ariz., also found the heat no obstacle as he cruised into Sunday's 1,500-meter final with a dawdling 3:46.44, followed by Sydney Maree, 3:46.61, and Todd Harbour, 3:47.07.

Tom Byers, by contrast, won the opening heat in 3:40.14, pulling five more runners into the final, as Sunday's field of 12 was determined on the basis of the first three finishers in each heat, plus the next three fastest finishers. Georgetown's Kevin Byrne, choking in the dry heat, was seventh in 3:46.1, so far back that the automatic timer did not clock him.

Maree, the NCAA champion with the best time in the field (3:35.30), and Scott, the No. 1 U.S. miler, were in the same heat because Scott had not competed at 1,500 meters this year and was ranked ninth here on the basis of an intermediate time, registered before he uncorked his potent kick in the mile.

Sixteen men, including Navy's Leo Williams, cleared 7 feet 2 1/2 inches to qualify for Saturday's high-jump final. Williams needed three tries to get over, as indoor champion Jeff Woodard was eliminated.

Cuban Alberto Juantorena, of 1976 Olympic-double fame, gained Saturday's 400-meter semifinals by placing third in his heat in 46.55. Also advancing were Willie Smith, Troy Darden, Herman Frazier and Cliff Wiley. Fred Sowerby, the D.C. International coach, bowed out in 47.2.

On a day when headwinds of more than 10 miles an hour inflated most times on the straightaway, Jackie Washington clocked an excellent 13.33 in the semifinals of the women's 100-meter hurdles. Gayle Watkins of D.C. International and Benita Fitzgerald of Woodbridge, Va., and Tennessee, also gained Saturday's final.

In the only first-day final other than walks and relays, Joan Benoit was a runaway winner of the women's 10,000 meters in 33:37.5.

John Gregorek of Georgetown, the NCAA runner-up, qualified for Sunday's final in the 3,000-meter steeplechase despite a queasy stomach. He nosed out Randy Jackson and Henry Marsh for third place in the first heat.

"They didn't know which was which, and there was no photo, because they couldn't move the camera to the finish line," Gregorek said. "So they wanted to know where we were on the track. Randy Jackson said. 'I was on the inside' and they said, 'You're fourth.' I told them I was on the outside and I got third. Marsh had to wait."