Weather and climate are obviously two separate things, but Neil deGrasse Tyson is here in case you need reminding.
"Weather is what the atmosphere does in the short-term, hour-to-hour, day-to-day," the "Cosmos" host explains in the clip above. "Weather is chaotic, which means that even a microscopic disturbance can lead to large scale changes. That's why those 10-day weather forecasts are useless ... Climate is the long-term average of the weather over a number of years. It's shaped by global forces that alter the energy balance in the atmosphere, such as changes in the sun, tilt of the Earth's axis, the amount of sunlight the Earth reflects back into space and the concentration of greenhouse gasses in the air."
Tyson compares weather to the irregular, sporadic pattern of his dog. Though it's difficult to predict where the dog is going, we can know the range of his meandering because he's on a leash. Conversely, Tyson's straight path is like the climate, which is broadly predictable by observing long-term changes in global forces.
Both man and dog have their own patterns, but both are going in the same direction.
The "Cosmos" episode that aired on June 2 uses the planet Venus as an example of what happens when the greenhouse effect runs rampant. In the episode, Venus is shown with boiling oceans and yellow skies.