Eyes are turning to the skies above the Red Bull Ring, with qualifying likely to be affected by heavy rain.
"It is supposed to rain buckets on Saturday," he said. "I'm curious to see if we can do qualifying at all."
Indeed, F1 race director Michael Masi agreed that the weather forecast is "very bad".
"We could have to move qualifying to Sunday morning," he is quoted by La Gazzetta dello Sport.
Mercedes' Toto Wolff said: "There should be torrential rain all day tomorrow, so I don't rule out that the second practice session will be regarded as qualifying."
In that session on Friday, Dutchman Verstappen was fastest ahead of last weekend's winner Valtteri Bottas.
World champion Lewis Hamilton is struggling.
"We're a little in the dark," Wolff told RTL. "The balance was not good on either car, but it was a catastrophe for Lewis.
"We are certainly the team that has lost the most compared to Verstappen."
A stand-out performer is Racing Point, whose Sergio Perez was never outside the top three on Friday.
Ferrari, meanwhile, still do not look fast in Austria despite running a new front wing and floor. A more upbeat Sebastian Vettel said it felt like "a different car compared to last week".
"Outside the cockpit I feel nothing, but as soon as my body is under strain I'm struggling," said last week's podium-getter.