They perform some more magic tests and run out of mana and recover mana and perform more tests and a second sleepover could be fun but it's decided that people can do coordinated tests in their own places and there is not actually a need for them to all be in the same place. The Maxwells' driver takes Jess home (and Maya, too, if she prefers that to staying with the Maxwells but they assure her she's welcome to stay there), then takes Sadde, Theo, and Tyler to the Farron residence, where Sadde prefers to be dropped—he'll go to his place by public transportation, he'd like to talk to the—twins?—yes, thank you, it was a pleasure meeting you.
"So, unknown alignment that is probably powerful – I mean, I guess we already knew that from it being a storm, but still – and has been loose for longer than the previous cards, so probably going to be harder to get."
The driving stops. The little window separating them from the driver lowers, and he says, "The streets seem to be flooded."
"Erm," says Willow eloquently.
"… We could possibly use the Change to turn it into ice, walk on it, briefly? That might be a bit large-scale for how we've practiced using it, though…"
"We could try sorcery instead, maybe charge some paper with 'Freeze' together, work out a spell?"
"We could cast something all together but it'd be—weird, wouldn't it? All of us walking on water? To onlookers."
"Should we try for invisibility? Or are we thinking of giving up, here, because that just sounds like this is going to get worse."
"We can fly and probably find the card—if it's the Storm it's probably, like, in the storm, yeah? And being invisible is probably a good idea."
"Didn't get proper invisibility last time I tried it with the Shadow, just darkness, might be a bit conspicuous or untested if we go for something else."
He grabs a few pieces of paper from his backpack and starts composing a little chant. "We could probably all help dump mana into them."
Then Theo can check which direction the card's in, they can get out of the car into the storm, and they can cast invisibility and flight.