Voyaging canoes Hokule'a and Alingano Maisu were losing ground Monday in their sail toward the Marshall Islands, apparently tacking against headwinds that were driving them eastward.

"At last report, they were encountering winds this morning out of the southwest" at 11 to 17 mph, said mission spokeswoman Kathy Thompson.

The canoes, which left the Big Island last week, had been sailing comfortably in light trade winds, but the same weather system that is causing gusty winds over the main Hawaiian Islands has settled a high-pressure ridge over the area where the canoes are — roughly midway between the Big Island and Johnston Atoll.

The canoes' morning report matches what National Weather Service forecasters were seeing on computer weather charts.

"If the models are correct, they've got headwinds (a little more than 10 mph), and it's going to be that for the near future," said Honolulu forecast office meteorologist Tim Craig.

Based on their automated position indicators, the canoes appeared to have tacked from a westerly course to the east-southeast overnight.

Craig said it could be Thursday or Friday before they get favorable winds for continuing on their preferred west-southwesterly course.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.