Virtual Weather is an umbrella term for meteorological phenomena on Lyoko, Replikas, other virtual worlds like the Cortex and the Volcano Replika, and in the Digital Sea. This article lists the various observed kinds.


Yumi Aelita running from a tornado
XANA clip image048-1-

X.A.N.A. showed the ability to create sandstorms in "Log Book", in the form of a large tornado. This decreased visibility significantly. X.A.N.A. used it to hide a Megatank. This has only been observed in the Desert Sector.

Mountain Fog

Tip-Top Shape Misty Mountain Sector image 1

Mountain Fog is exactly what it sounds like. It is fog in the Mountain Sector. This is always present in the Mountain Sector to a degree. However, sometimes it gets a lot thicker. This thickening was observed in "Tip-Top Shape" and "Revelation". In "Revelation", it was used to hide the approach of 3 Tarantulas. In "Tip-Top Shape", X.A.N.A. fogged over the entire sector to make it harder to navigate.

Digital Sea Flooding

Raz de maree 153

In "Tidal Wave", the Digital Sea overflowed, and flooded the surface remaining surface sectors with the sea. This was also caused by X.A.N.A., and had to be repaired in Sector Five. This did not affect the towers or the sectors, but was lethal to monsters and avatars.

Cortex Clouds


In most appearances of the Cortex, a lot of clouds are visible beyond the land of the sector. The clouds surround the area, but don't touch it directly. Instead, there appears to be a buffer zone of neither land nor clouds, which is about half as wide as the land covered part of the Cortex itself. This also appears in the concept art.

Glacial Expansion and Contraction

Vertigo Aelita freezes the Scyphozoa image 1
Retour 265

Rather than being a natural phenomenon, the growth and shrinking of ice in the Ice Sector appears to be entirely artificial. In "Down to Earth", Jeremie's Multi Agent System was used to radically expand the ice in the Ice Replika, to constrain the Kolossus. In several episodes, such as "Saint Valentine's Day" and "Vertigo", Aelita used her Creativity to expand the ice to constrain or block enemies.

Glacial Breakup and Drift

Tentation 355
Tentation 326

Like Glacial Expansion and Contraction, Glacial Breakup and Drifting is mostly artificial. In "Temptation", Tarantulas fired repetitive shots at the ground, causing it to fracture and break up. Rather than being a discrete landmass, the area became a bunch of small glaciers. Due to everyone moving on them, as well as the normal water physics in the Ice Sector, the glaciers shifted around a lot.

Digital Sea Waves

Surmenage 357
Intrusion 157

Despite looking peaceful at a distance, the surface of the Digital Sea is actually very turbulent. The waves are obvious in any shot close to the surface. In "Code Lyoko Evolution", this effect was toned down a little.

Lava Waves


Like the Digital Sea, the lava in the Volcano Replika has a turbulent surface layer, when observed closely. This is actually rendered using the same effects and animation object recolored. This phenomenon was only observed in "Code Lyoko: Fall of X.A.N.A." and "Code Lyoko: Quest for Infinity".

Virtual Water

William and Ulrich Fighting in the Forest
Aelita Looking in the Digital Sea

Virtual Water is the presence of ponds on Lyoko. Unlike the Digital Sea, it is completely harmless and mostly decorative. It can be seen in the Ice and Forest Sectors. In the Forest, it was seen in "Holiday in the Fog", "Temptation", "Opening Act", and "Quest for Infinity". In the Ice Sector, it is extremely common. In "Vertigo", Odd swam in it so he could sneak past a couple of Hornets in order to save Aelita from the Scyphozoa.


Earthquakes are one of the more common phenomenon in both the virtual and real world. In "Just in Time", X.A.N.A. caused a chain of earthquakes in Boulogne-Billancourt. X.A.N.A. also caused several earthquakes mentioned but not shown in the video games "Quest for Infinity" and "Fall of X.A.N.A.." The most common example of earthquakes is in the Cortex. There, earthquakes typically precede the Cortex Shifts.

Cortex and Sector Five Shifts

Cortex and Sector Five Shifts are two closely related phenomenon. In Sector Five, the Sector Five Replika, and the Cortex; the massive blocks that the sector is made out of can shift around. In the case of the Cortex, this is a security feature/ byproduct of incomplete code. In the Sector Five Replika, this was a security feature left in place by X.A.N.A., after he copied the code for the original Sector Five.

In Sector Five's case, this phenomenon is highly diverse. It occurs in the key chamber whenever one hits a Key Mechanism, allowing them to climb. It also occurs whenever the Sector Five Security Countdown hits zero, potentially trapping or devirtualizing the victim. Other instances include whenever the Transport Orb arrives in the Core Zone, as the sector rearranges. Some block shifting is also present in the form of a trap. Variations of this include collapsing floors, shifting floors, people being crushed, etc. In the video games, Sector Five shifting is a major obstacle. Finally, whenever somebody hits the key mechanism before the countdown hits zero, some blocks shift to reveal the elevator.

This phenomenon is extremely dangerous. In "Exploration" and "Cortex", several people were devirtualized by being crushed, and weren't easily re-materializeable. This was rectified by configuring the sectors to work with the materialization program. People also can get trapped, which happened to Aelita.

A point of confusion is the incident in "Plagued", when a massive platform in the Desert Sector rotated to a 90 degree angle. This wasn't a natural phenomenon. This was X.A.N.A. using the Sector Alteration Program.

Sector Collapse and Deletion

The Overboard Falling into the Digital Sea
Desert sector destroyed
Common interest 18
Sabotage 366
Hard Luck The Skid leaves image 1

Sector Collapse and Deletion is a rare phenomenon that occurs to sectors or Replikas when the hardware that supports them is damaged, or the software supporting them is halted or fails. In non-Cortex areas, the phenomenon, as observed in the sector, consists of the colored panels of the sector dissolving away in patches, with the vector lines receding afterwards, in patches. This includes the dissolution of Lyoko Wires and towers. In the Cortex, this consists of the various modules of the Cortex falling into the Digital Sea in pieces, in a pattern emanating outward from the center. In worlds where the sector in question is the only sector, such as Replikas, the Virtual World Shell usually explodes afterwards.


Volcanic Plumes and Lava Movement

Virtual Lighting

Virtual Atmospheric Turbulence

Hyperfluid Currents


Pulsations in the Desert Sector image 1

The episode "Seeing is Believing" is the only one to feature an Oasis so far. It is located in Desert Sector, surrounded by a wall of a few large rocks and several smaller ones and a few shrubs. In the middle, there is a pool of the Virtual Water. However, this is only an illusion; this is actually a surface layer which conceals a passage to the lower platform of the sector where the activated tower was located.