Points to Remember. 1  Marijuana refers to the dried leaves, flowers, stems, and seeds from the hemp plant, Cannabis sativa. 2  The plant contains the mind-altering chemical delta-9-tetrahydrocannabinol (THC) and other related compounds. 3  People use marijuana by smoking, eating, drinking, and inhaling it.
A cold front is symbolized on a weather map as a line with triangles. The triangles can be thought of as icicles. Cold fronts are often coloured blue. The presence of a cold front means that cold air is advancing and pushing underneath warmer air.
Though the cold it brings can factor into winter weather, for the most part the polar vortex is not in itself a weather maker, being quite high in the atmosphere. Winter weather is more shaped by the position of the jet stream, along which low pressure systems move. In practice, the northern jet stream is the boundary between cooler air from the north and warmer air from the south, though the jet stream is not as high in the atmosphere as the polar vortex.