Those lucky enough to be in the eclipse's path of totality are crossing their fingers for clear skies on Monday, hoping for the best chance to stand in complete darkness, oohing and ahhing as the moon passes between the sun and the Earth.
But those plans could be ruined by something as unpredictable and uncontrollable as the weather. Forecasts warn of possible storms over large swaths of the 115-mile-wide path from Texas to Maine, bringing with them thick heavy clouds that could obscure the rare celestial event.
Thunderstorms are expected in Texas, Arkansas, and parts of Missouri, Jen Carfagno, an American meteorologist with The Weather Channel, told NPR's Here & Now.
But that's not necessarily cause for despair.
"Often thunderstorms develop during the late afternoon, even early evening, so there's a lot of hope that maybe clouds won't form until after the eclipse happens," Carfagno said.
Clouds can also vanish during an eclipse as temperatures cool because of the sun getting blocked. "Sometimes that prevents air from rising to create the clouds. So air rises because it's warmer than other air around it. So if air is cooling it may not rise and it may at least prevent clouds from thickening or building," Carfagno explained.
There are also lots of different types of clouds; thin or sporadic clouds can leave gaps over the sun, allowing for at least temporary peeks.
And there's more good news for people in northern Maine where a nor'easter is slamming residents. Carfagno said that the storm should clear out by Monday, making it one of the best spots to look up at the sky — wearing special eclipse glasses, of course.
So, while nobody knows if there will be clouds above during the 4-minute window of the perfect corona around the sun, there are still several ways to enjoy the wonders of such a phenomenon in less than ideal conditions.
Here are a few ideas on how best to take in the experience.
Make a back up plan and be ready to move
The first piece of advice from true umbraphiles — what eclipse chasers are called — is to be ready to move, move, move.
Dan McGlaun, an eclipse expert and founder of Eclipse 2024, has traversed the globe for the best views of the last 15 total solar eclipses.
To get out from under hazy weather or thick clouds, McGlaun suggests checking an eclipse tracker, like the one he has created on his website, then jumping in a car to the nearest unobstructed view of the sky.
That's what he did to see the 2017 solar eclipse over Carbondale, Ill. "We got in our cars and we drove in the direction the cloud was moving. We got way out from underneath it and we saw the whole eclipse," he recalled.
In these situations, planning is king, which means having a pre-planned route to the final destination in order to avoid traffic snarls, McGlaun suggested.
For those with the passion and the resources to take more extreme measures, the self-described chief eclipse officer said they "will have airplanes on standby so they can get out an hour early and go somewhere looking there or they can get above the clouds and see it from the air."
Barring any kind of mobility, the best option is to live in the moment
Even in the worst case, there are physical changes that people in the path will still experience. Temperatures will drop and it'll get very dark very quickly. At the same time, animals will also come alive in a unique way, particularly nocturnal creatures. That's because their behavior is regulated by light levels.
As David Baron, author of the 2017 book American Eclipse, told NPR, standing in that kind of darkness is a highly emotional, full-sensory experience.
"The air temperature drops because the sunlight suddenly turns off. And you're immersed in the moon's shadow. It doesn't feel real," Baron said, adding that "birds will be going crazy. Crickets may be chirping,"
And humans are not exempt: "If you're around other people, they're going to be screaming and crying [with all their emotions from seeing the eclipse]."
Making lemonade out of eclipse rain
This year, whether the weather cooperates or not, McGlaun plans on watching the eclipse from his front yard in Indiana.
"The prospect of seeing one from my house is so special that it overrides even the possibility of me missing it. I would still count it," he said, giddy with excitement.
McGlaun suggests gathering neighbors and friends for a celebration of the celestial wonder, even in the absence of clear skies. Preferably one set up with a large outdoor screen to accommodate NASA's live stream of the event. Having telescopes, solar filters, and interactive activities on hand might also help children get the most out of it.
The thing to remember is that every total solar eclipse is special. "We were still part of a wonderful cosmic alignment," he said.
While he is optimistic that the expected storms across Indiana will dissipate prior to the eclipse, McGlaun said he's ready for anything.
He recalled that in 2009, after racing to Shanghai, China, to witness the eclipse, he found himself clouded out with no options of getting to a better spot. In an effort to make lemonade out of lemons, he said, "I set out drinking glasses and I caught rain that fell during totality. And so I have these vials of eclipse rain."