Weather warning side companies like Weather Watch or Instant Weather. These side companies are not associated with the government in any way. Environment Canada defines a advisory as ""an alert to cover a wide array of deteriorating weather conditions,"" a watch as ""when conditions favour that severe weather forming"" and a warning as ""severe weather is actually occurring or is imminent."" . Additionally, Environment Canada breaks down weather alerts based upon the specific type of hazardous weather. These alerts are regionally issued throughout Canada and include, but are not limited to, winter storms, extreme temperature, ice, thunderstorms (including tornadoes), wind, tsunami, tropical
Weather understandings of what weather is, what makes it change, the effect it has on humans in different situations, etc. Therefore, weather is something people often communicate about. Weather has played a large and sometimes direct part in human history. Aside from climatic changes that have caused the gradual drift of populations (for example the desertification of the Middle East, and the formation of land bridges during glacial periods), extreme weather events have caused smaller scale population movements and intruded directly in historical events. One such event is the saving of Japan from invasion by the Mongol fleet of Kublai Khan