The Great Storm of 2010 was an event that took place from October 28 to November 14, 2010. It was first confirmed in issue #261 of the Club Penguin Times. This storm lasted longer than any other, as said by Gary the Gadget Guy in issue #261 of the Club Penguin Times. The storm was a sign for rain for the first time ever in Club Penguin history as predicted by Gary the Gadget Guy, Weather Experts and even Sensei, and led to the Celebration of Water.
Gary the Gadget Guy confirmed in the Club Penguin Times that a storm would hit Club Penguin Island just in time for the Halloween Party 2010. This is the third 'Great' Storm; the first one was in October 2008 for the Halloween Party 2008 and the second was in October 2009 for the Halloween Party 2009. It started to rain on November 11 as Gary the Gadget Guy predicted. The rain led to Card-Jitsu Water. A few days after Gary's prediction, Billybob confirmed that the storm would hit on October 28, 2010 and would continue into November.
The thunderstorm struck Club Penguin on the evening of October 28. Loud lightning and gale-force winds continued into October 29 and into Halloween. In November, rumors were started that another game would open in the Dojo after this storm was over. Rain began pouring on November 11, and the lightning and gale-force winds began to weaken. Finally, on the morning of November 14, the storm left Club Penguin and dissipated in the northwest.
- Unlike other storms in Club Penguin, this one did not have lightning.
- After it started raining, a few rooms had special changes, aside from the normal puddles.
- The fire at the Cove was put out. The lanterns in the Fire Dojo were put out as well.
- The watering system at the Mine Shack activated continuously and automatically, due to the rainwater powering it.
- In the Ninja Hideout, the water symbol on the large amulet on the floor was covered in some water after it started raining, teasing Card-Jitsu Water.
- After the Halloween Party 2010, the storm wasn't featured on the map anymore, even though it was still taking place.
- This was the first time there was rain in the island. The only earlier appearance of rain was in the Melting Background.
- The Rainy Day Background is based on this event.
- The storm is featured in multiple Card-Jitsu Cards: Stormy Sky, Storm Baffles Gary, The First Rainstorm, and Sign From The Elements.