Millions are hoping for clear skies as anticipation grows ahead of Monday’s total solar eclipse.
Forecasters are predicting cloudy conditions in northern Mexico, Texas and parts of the Great Lakes region.
Better weather is expected in western Mexico and parts of the US Midwest, with clear spring skies likely in New England and Canada.
The total solar eclipse, the first to cross the continent since 2017, will first hit land on Mexico’s west coast.
It will track north-east across heavily populated areas and several major cities in three countries.
Some areas along the path of totality – where the moon totally obscures the sun – will experience darkness for nearly four-and-a-half minutes.
According to Nasa, 31.6 million people live along the path of totality, and millions more are expected to travel to catch a glimpse of the celestial event.
At the Starry Night RV park in Fort Worth, Texas vehicles full of eclipse watchers were rolling in to set up camp ready for the big moment.
Owner Lindsey Kuhn told the BBC: “It’s becoming quite a big deal, people have driven here from all over.”
“I’ve been trying to explain to my daughter that it’s going to get dark, she asked ‘will we have to go to sleep?’
“We’re going to be together, put on our glasses and take a selfie, it’s once in a lifetime for us.”
Except during the period of totality, special glasses are needed to view the partial stages of the eclipse. Experts advise that regular sunglasses won’t work and looking at the sun, even through a camera or smartphone, can cause eye damage in seconds.
Special events are being planned in towns and cities across the path.