风力仍在增强，接近九级。

The wind was still rising, approaching a force nine gale.

《柯林斯英汉双解大词典》

五分钟后，美国国家飓风中心(NHC)将西莉亚归类为伴随每小时215千米(每小时135英里)持续风力的4级飓风。

Just five minutes later, the U.S. National hurricane Center (NHC) classified Celia as a Category 4 hurricane with sustained winds of 215 kilometers per hour (135 miles per hour).

youdao

应该说，到目前为止一切都还算顺利，今天海上并没有多少风力可以借助，下午有几个小时的风速为15-20kt (1 kt = 0.514444444 m /s，8.0-10.7m/s就算劲风了，5级吧)。

Sofar things have gone well. There hasn't been much wind during the day, and I've been getting a few hours of 15 -20 kt winds in the afternoon.

youdao