How Weather Works

Who knows what weather is?

Who knows what meteorologists do?

What Is A Meteorologist? Meteorology is the study of the movement of air around and above us (the atmosphere!) Aristotle is considered the father of meteorology and wrote the first major book on it in 340 B.C., 2,349 year ago! Benjamin Franklin We study weather to predict what it will do next so we can keep people informed and safe!

Layers Of The Atmosphere Thermosphere - Where space shuttles orbit Mesosphere - Where meteors burn up Stratosphere- - - Where the ozone layer is Troposphere - - Where all of our weather happens

Weather And Energy

Weather And Energy The sun causes all our weather because it heats the earth unevenly (warm equator, cold poles) This uneven heating causes the atmosphere (air around us) to act like a huge engine trying to move all of the heat to the right places.

Weather And Energy This engine keeps warm and cold air moving which is what creates wind! Warm air likes rising and cold air rushes in to takes its place. The engine also causes moisture to lift upward which creates clouds, storms, lightning, and even tornados!

Water cycle

Who knows… What the 4 seasons are? Why we have the 4 seasons?

seasons

Who knows what a thunderstorm is?

What Makes A Storm Storms need 3 ingredients to be created: Instability – The sun Lift – Cold Air Moisture – Water in the air

Parts Of A Storm Cumulus clouds (Puffy/Cauliflower Clouds) Cumulonimbus clouds - storm making clouds They can reach up to 55,000 feet in the air, or the same level air planes fly!

Parts Of A Storm Updraft - where all the moisture is pulled up into the cloud

Parts Of A Storm Downdraft – where all the rain falls out of a cloud

Where Does Lightning Come From? Lightning is electricity that is created when all of the ice crystal, water droplets, and hail in a big storm run into each other. All this moving around creates a negative and positive charge to the cloud The different “charges” on the ground start to separate because opposite charges attract

Where Does Lightning Come From? When there are enough of the same charges all together, lightning happens! Lightning bolts are extremely hot, with temperatures of 30,000 to 50,000 degrees F. That’s hotter than the surface of the sun! Lightning moves about 75 miles per second! Every second, about 100 lightning bolts are happening all over the Earth!  

Staying Safe With Lightning The 30 Rule: If the time it takes to hear thunder after seeing lightning is less than 30 seconds; it’s time to go inside! Lightning can travel up to 10 miles away from the cloud it comes from. Lightning likes tall objects, so make sure you are low to the ground if you are outside when a storm is coming and be sure to stay away from tall objects like trees!

The safest place when thunderstorms and lightening are near is inside a building, such as a house or school, and away from windows. Inside a car or school bus are also a safe place if a building is not near. You also do not want to use corded phones or take a shower or bath in an electrical storm either. Lightening can travel through wires and metal pipes.

What Is Hail? The top of a cloud is very cold! When raindrops are pushed very high in a big storm they can freeze and start making hail!

What Is Hail? The largest piece of hail ever recorded weighed nearly 2 pounds and was almost as big as a soccer ball! Hail can fall at over 100 mph!

Heavy Rain and Floods

Supercells And Tornados

What Is A Supercell? Supercells are huge thunderstorms where the updraft turns in a circle. It does this because of shear Shear - wind coming from different directions and speeds as you move higher in the sky.

Parts Of A Supercell Overshooting top This "dome" feature appears above the anvil of the storm. It is a result of the powerful updraft. If an observer is too close to the storm, the overshooting top cannot be seen from the ground. Precipitation-free base This area, typically on the southern side of the storm in North America, is relatively precipitation free. This is located beneath the main updraft, and is the main area of inflow. While no precipitation may be visible to an observer, large hail and rain may be falling from this area. It is more accurately called the main updraft area. Wall cloud The wall cloud forms near the downdraft/updraft interface. This "interface" is the area between the precipitation area and the precipitation-free base. Wall clouds form when rain-cooled air from the downdraft is pulled into the updraft. This wet, cold air quickly saturates as it is lifted by the updraft, forming a cloud that seems to "descend" from the precipitation-free base. Wall clouds are common and are not exclusive to supercells: Only a few actually produce a tornado. Wall clouds that persist for more than ten minutes, wall clouds that seem to move violently up or down, and violent movements of cloud fragments (scud or fractus) near the wall cloud are indications that a tornado could form. Mammatus clouds Mammatus (Mamma, Mammatocumulus) are bulbous or pillow-like cloud formations extending from beneath the anvil of a thunderstorm. These clouds form as cold air in the anvil region of a storm sinks into warmer air beneath it. Mammatus are most apparent when they are lit from one side or below and are therefore at their most impressive near sunset or shortly after sunrise when the sun is low in the sky. Mammatus are not exclusive to supercells and can be associated with developed thunderstorms and cumulonimbus. Precipitation area This is the area of heaviest precipitation. Between the precipitation-free base and the precipitation area, a "vaulted" or "cathedral" feature can be observed. In high precipitation supercells an area of heavy precipitation may occur beneath the main updraft area. Flanking line A line of smaller cumulonimbi or cumulus that form in the warm rising air pulled in by the main updraft. Due to convergence and lifting along this line, landspouts sometimes occur in this region.

Supercell Pictures Mammatus clouds Anvil Cloud Wall Cloud

Where Do Tornados Come From? Tornados are the end of the big spinning updraft in a supercell reaching the Earth

Tornado Facts They can spin around at over 300 miles per hour and move forward at 60 miles per hour! Tornados can be over 2 miles wide! What to listen for on the radio and T.V. TORNADO WATCH: Tornadoes are possible in your area. Remain alert for approaching storms. TORNADO WARNING: A tornado has been sighted or indicated by weather radar. If a tornado warning is issued for your area and the sky becomes threatening, move to your place of safety like a basement or room in the middle of your house.

Inside Of A Tornado

Forecasting Radar Satellite Surface Observations Computer Models Knowledge