The Weather and Climate Command Center was a facility in the heart of the Lost City of the Jedi. According to DJ-88, droid administrator of the Lost City, it was the Control Center which was actually responsible for regulation of the climate of Yavin 4. DJ-88 claimed that Yavin 4 had originally been a frigid ice world before ancient Jedi Masters terraformed its surface and opened vast steam vents to warm and water imported foliage. The water vapor output of the vents was controlled by the Weather and Climate Control Center. Under the tireless, millennia-long direction of the Center's droid operators, Yavin 4 settled into a six-month wet season contrasted with a six-month dry season. During Trioculus' onslaught on Yavin 4, Treaded Neutron Torches set fire to the moon's vast rain-forests. Fleeing the unquenchable blaze, Luke Skywalker entered the Lost City through one of the titanic steam vents and petitioned DJ-88 for help in defeating the Imperial forces. Although the moon's wet season was months away, DJ-88 ordered that the steam vents be opened prematurely. Skywalker, himself provided the code necessary to activate the ancient Climate Control machinery, an alphanumeric sequence which the Force spirit of Obi-Wan Kenobi had imparted to him in a dream: 'JE-99-DI-88-FOR-00-CE'. Upon receipt of this activation code, the steam vents opened to full capacity. The resulting condensation generated massive thunderstorms which doused the raging wildfires. Presumably, the Weather and Climate Control Center was sealed after the abandonment of the Lost City of the Jedi.
Behind the scenes
At first glance, the designation "Weather and Climate Control" may appear redundant. However, in-depth study of the meteorological sciences (and/or Wikipedia) reveals the distinction between weather and climate: "Weather is a term that encompasses phenomena in the atmosphere of a planet. Weather is the state of the logical and scientifically explained atmosphere at a given time and place. The term usually refers to the activity of these phenomena over short periods (hours or days), as opposed to the term climate, which refers to the average atmospheric conditions over longer periods of time." (from Wikipedia: Weather.) Clearly, the ancient Jedi Masters had an advanced understanding of meteorology.
Multiple numerological interpretations of the mysterious activation code 'JE-99-DI-88-FOR-00-CE' are possible. From an in-universe perspective:
In the arcane numerology of the Bendu monks, the number nine (often represented symbolically as eight spokes within a ring) represented the beneficent presence of the Force in a unitary Galaxy. Eight, of course, is the number of spokes within the "Bendu Wheel", most likely symbolizing the totality of life encompassed by the unbroken, self-feeding circle of the Force. A zero value could represent either the inevitability of life's end and re-absorption into the currents of the Force or the mutual cancellation of the negative and positive values of the Light and Dark sides. The double repetition of each number (99-88-00) could signify the conflicted duality of the Force's nature in Jedi dogma. By this scheme of interpretation, '99' is the eternal cycle of Bogan and Ashla, '88' is the life, both good and evil, generated thereby, and '00' is the ultimate annihilation of these oppositely polarized qualities, similar to the destruction of matter and antimatter. The significance of the letters 'JE-DI-FOR-CE' is indeterminate but possibly represents the bond between the Jedi Order and the will of the Force.
- Weather on Wikipedia