3 19 cumulus cloud hot air is rising a lot of vapor mature stage cloud gets longer some warm moist air is still rising while some lowers and pro duces heavy rain they convect into each other and produce a supercell thunderstorm sometimes thunderstorms create flash floods contain tons of debree and flow almost like a river are very dangerous flash floods are the number one killer from thunderstorms we are now pretty good at predicting thunderstorms and rain we can call out flash flood warnings certain areas are prone to flash floods scientists can go in and map out channels where floods have already occurred and produce a building code so that people don t build there death toll of flash floods is decreasing tornados rotation of air movement with really high energy able to pick things up as big as houses they are extremely destructive can occur almost anywhere in the world only a few minutes duration normally travels around 6 kms can travel up to 70 mph but usually around 30 mph 99 of tornados in northern hemisphere rotate counter clockwise driven by coreolis borealis risk of dying in a tornado is pretty small problem isn t death toll but destruction how to tornados develop Mesocyclone open area and wind traveling over area because wind gets slowed down by ground surface through friction top moves faster ground is warm as well and produces updraft which allows a thunderstorm to start to than bottom form all cloud material starts to get picked up and rotated which produces mesocyclone produces funnel shaped system some mesocyclones hit ground some don t a tornado looks like a little tube of air spinning with a massive cloud above it the big cloud that forms above tornado is a thunderstorm cloud so it produces heavy and light rain the other way tornados are produced is when cold fronts and low fronts move against eachother often in america warm air from florida hits cold front from canada produces convergent zone where convection begins to occur which forces the air to go up suddenly the air gets to upper levels and is still rotating and as more air comes tornado grows and starts to move