CALGARY, FEB. 22 -- Bonnie Blair, a 5-foot-3 mite who learned how to speed skate while jostling through crowds in Champaign, Ill., gave the United States only its second gold medal of the XV Winter Olympics tonight, winning the women's 500-meter speed skating.

Blair, who came here sponsored by her hometown police department, took the starting line shortly after favored Christa Rothenburger, the world and defending Olympic champion from East Germany, had set the world record at 39.12 seconds, breaking her own previous mark of 39.39.

"I really didn't see her skate . . . but I did see her time," Blair said. "When I opened up faster than she did . . . I almost knew I had it then."

Blair, 23, bettered Rothenburger's time at every interval and strode to the gold by two-hundredths of a second. An indication of how fast Blair's time of 39.10 was: it would have won the men's 500 meters in every Winter Olympics through 1976.

"I think I just got it on guts," said Blair.

Although Rothenburger was favored to win the race, Blair represented a considerable threat. She was the world champion in 1987, setting a world record of 39.43, the mark Rothenburger first broke.

This was the first women's speed skating gold medal for the United States since Sheila Young won in 1976 in Innsbruck, Austria. The only other U.S. gold medal here was won Saturday night by men's figure skater Brian Boitano.

Beyond the record-setting performance, the weather's continued pillaging of Olympic schedules was the overriding issue of the day.

With weather problems continuing, organizers had hoped to have the luxury of an extra day to complete events after the closing ceremonies coming up Sunday. But International Olympic Committee officials said today that the Games will end when the Olympic flame is extinguished, raising the possibility that some medal events will not be completed.

And even in one of the events that was completed, weather was a factor. Soviet driver Ianis Kipours used a lead he had built in the first two runs during Saturday's deteriorating conditions to hold off East Germany's Wolfgang Hoppe in the two-man bobsled. Kipours pulled off the upset by seven-tenths of a second even though the defending gold medalist had better times in both of today's runs.

Those events that weren't subject to weather were subject to upsets. The Austrian Alpine ski team continued its domination of the heavily favored Swiss when Sigrid Wolf won the women's super giant slalom for her country's third gold medal.

The Swiss were predicted to win as many as "I think I just got it on guts."

-- Bonnie Blair

eight Alpine gold medals, but so far have just one. World Cup leader Michela Figini of Switzerland took the silver today, her first of the Games, and Karen Percy of Canada got her second bronze medal, adding to her third place in the downhill.

In cross country skiing, Sweden won the men's 4x10-kilometer relay. The Soviet Union had won four of the five previous cross country skiing races. Soviet Mikhail Deviatiarov fell on a downhill stretch just after being overtaken by Sweden's Gunde Svan, and lost almost 15 seconds. The U.S.S.R. settled for the silver, while Czechoslovakia took the bronze.

Finland became the sixth and final team to advance to the hockey medal round with a 5-1 victory over a Polish team that the previous day had been penalized when star forward Jaroslaw Morawiecki tested positive for the high levels of testosterone usually associated with steroid use. At a news conference this morning, the player and team officials said security at the venue was lax, and perhaps he had taken a drink loaded with the drug, commonly used for building strength.

The bleak, ice-patch Calgary landscape was again beset by gusting winds, causing the postponement of the individual 90-meter ski jump at Canada Olympic Park. It will be held Tuesday, assuming the wind proves more accommodating.

Ski jumping officials and athletes alike were exasperated by today's postponement, the third straight. The 90-meter team jump also was postponed from last Wednesday to this Wednesday.

Once again, the jumpers ascended the jump only to be elevatored down. Rob McCormack, chief of competition for ski jumping, said he is "worried about the skills of the competitors because of the psychological torture" of going up and down the hill day after day without getting to jump.

Torbjorn Yggeseth of Norway, the International Ski Federation's technical delegate, said, "All the skiers wake up thinking they're going to be competing and then go back in afternoon disappointed. That's mental cruelty in my mind."