The Storm ended five games of misery as they ran in eight tries to one, with six coming in the opening 40 minutes.
Melbourne fell off dramatically in the second half and looked more like the side that has struggled in recent weeks, but their work was already done after setting up a 34-0 lead by the halftime break.
The spoils were shared around with winger Sisa Waqa crossing for a double, including one only 35 seconds into the match to set the scene for the blood-bath.
Centre Justin O'Neill, returning from a groin injury, also crossed twice, as did halfback Cooper Cronk.
The Panthers, down in 15th position, were looking to claim three successive wins for the first time since 2010 but they ran into a Storm outfit determined to stop their slide down the NRL ladder.
Melbourne also had their first-choice halves pairing of Cronk and five-eighth Gareth Widdop playing together for the first time since mid-June and Cronk in particular relished the extra time and space as he shared the playmaking duties.
As well as his own two tries, Cronk had a hand in three others in a busy afternoon.
Fullback Billy Slater didn't get across the tryline but, in his second game back from his knee injury, showed glimpses of returning to his best form.
Penrith were on the back foot from the opening whistle and only managed three tackles before the Storm's big three - skipper Cameron Smith, Cronk and Slater - combined and then sent the ball wide to a rampaging Waqa.
To the visitors' credit, they managed to stem the flow of tries in the second half with their defence, practically non-existent in the first half, more committed in the second 40 minutes with the Storm only crossing twice.
Young Panthers five-eighth Lachlan Coote was forced off the field just eight minutes into the match with a cut below his eye and while he was off the Storm scored twice.
But he returned and toiled hard in the losing side.
The only moment of joy for the Panthers came with nine minutes left in the match as replacement Matt Robinson broke through to touch down for their sole four-pointer.
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