That's what the press is reporting, but the Saudis don't have 150,000 troops or anything close to that--and they aren't about to risk their National Guard to help the Army. Maybe the press is including Egyptian troops or something.
The Saudi air force will do fine, I think, but I have real doubts about the Saudi Army against the Houthis. Last go around the Saudis did not do well, and my guess is that they will once again throw the most questionable troops from the most potentially disloyal tribes into the battle first in the normal Arab manner. Meanwhile the Houthis seem extremely competent militarily (even if they have overreached politically).
Back in Washington, Obama and Jarrett are no doubt trying to figure out why this is all the US's fault while the White House political team will be explaining to the eager press how it is really Bush's fault.
That's the trouble with power vacuums. They don't stop wars, they merely create new ones.