Mr. Trump set up the Presidential Advisory Commission on Voter Integrity to find evidence for his debunked claim that millions of votes were cast illegally in the 2016 presidential election. On Wednesday, the group sent a letter to all 50 secretaries of state asking for personal data about the nation’s 200 million voters.

The response from many of the state voting officials was a resounding “no.” In Mississippi, the secretary of state, Delbert Hosemann, a Republican, said: “My reply would be: They can go jump in the Gulf of Mexico.”

Mr. Trump’s tweet suggests that he is not happy with those responses, but it is unclear what he can do about them. The commission chairman told news organizations on Friday that it was up to each state to decide what information to share with the panel.

The president started his Saturday tweet storm on a positive note, offering a “Happy Canada Day” to the people of that country and to his “new found friend” Justin Trudeau, the prime minister.

But his tone quickly turned negative.

He continued his attack on Joe Scarborough and Mika Brzezinski, the hosts of MSNBC’s “Morning Joe,” two days after saying on Twitter that Ms. Brzezinski had been “bleeding badly from a face-lift” during a social event last year.

On Saturday, he added: “Crazy Joe Scarborough and dumb as a rock Mika are not bad people, but their low rated show is dominated by their NBC bosses. Too bad!”