move at a good clip
すでにふれられている内容ですが、私はUSA Todayより表現を拾います。
In total, 17 people have died as a result of the storms in Oklahoma and Texas since Friday. Another 13 people were killed when a tornado touched down in the Mexian border town of Ciudad Acuna, Monday.
Officials said the river at one point rose 12 to 14 feet in a matter of 30 minutes overnight Saturday. The river is still moving at a good clip.
"This was no joke. It was a wall of water," said Gay Sullivan, adding that she and her husband, Mike, knew it was time to go.
"He told me this is different, because we have been through a lot of floods. This house has never flooded, and he said this one is different," Sullivan said.
City officials knew, too. Sullivan said the warnings were frequent and stern on the landline.
"We were kept posted, posted, posted," she said. "By the last message — because the phones went out — they were frantic telling us it was coming ... move to higher ground. ... it was coming."
http://www.usatoday.com/story/news/nation/2015/05/27/texas-reels-from-floods/27996705/
とりあげる表現は“moving at a good clip”です。『Wisdom英和辞典第３版』（三省堂）によると、「move at a good clip：すばやく動く」とありました。“clip”が気になったので調べてみると、「クリップ、を切り抜く、刈込み」といった意味のほかに「（くだけて）すばやい動き」という意味もありました。ここでは「川の流れの速さ」について用いられています。
過去１０年でみると、最悪の洪水となったようです。テキサス州ヒューストンでは、わずか数時間で250ミリ以上の降雨を記録しました。（Chris）
