Call for rain on June 14

The Tangerine Palpatine's parade is scheduled for June 14. It would be a shame if it were rained out. I understand there could be downsides to attempting to influence the weather. But my thought process is that it will drive crowds away, and force him to cover up the things he thinks will bring him glory. His display of 'greatness' will naturally be reduced. And as we know, he'll become a whiny baby about it.
New moons are connected with lower atmospheric pressure (and thus, rain), so I propose we do a working to call for rain at the closest new moon, May 27, to fall on the parade on the 14th. Open to suggestions for incantations and materials.