The biggest U.S. trade gateway with Asia is clogged with the most inbound container vessels in more than six months, threatening to extend transportation delays, bite further into margins for American importers and boost prices for consumers.

Thirty-seven ships were anchored awaiting berth space outside the twin ports of Los Angeles and Long Beach, California, as of late Sunday, the most since early February, according to officials who monitor marine traffic in San Pedro Bay. That’s almost double the length of the queue in mid-July and close to the record of 40 anchored vessels set Feb. 1.

The average wait for berth space was 6.2 days, compared with 5.7 in late June, according to L.A. port figures. That number peaked around 8 days in April.

The transpacific trade routes have been disrupted in recent days by the partial closure of a major port in China because of Covid outbreaks among employees. That’s helping reduce already tight container shipping capacity globally and keeping ocean freight rates near record levels.