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You will first go to your Expert groups and research about your assigned natural disaster. Put any information you find on the Google Doc. There is a link on this board, as well as a link to the website for your natural disaster. Once you have the information you need, you will move to your Home groups and each person will talk about the natural disaster. Each person will have a different natural disaster so make sure you allow each person enough time to talk about the information they found. No more than 3-5 minutes a piece. After each group is finished, you will go back to your seats and we will talk about it as a class. This is a fun activity that allows you to find out information on each natural disaster, so do your part and participate accordingly! :)

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Tornadoes: 1, 7, 13, 19
Hurricanes: 2, 8, 14, 20
Earthquakes: 3, 9, 15, 21
Wildfires: 4, 10, 16, 22
Floods: 5, 11, 17, 23
Droughts: 6, 12, 18, 24

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Group A: 1, 2, 3, 4, 5, 6
Group B: 7, 8, 9, 10, 11, 12
Group C: 13, 14, 15, 16, 17, 18
Group D: 19, 20, 21, 22, 23, 24

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This article gives a lot of information about tornadoes. If you need more information, you may use another credible website. Just be sure to provide a link to the website you use.

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Severe Weather 101

Tornado Basics

What is a tornado?

A tornado is a narrow, violently rotating column of air that extends from a thunderstorm to the ground. Because wind is invisible, it is hard to see a tornado unless it forms a condensation funnel made up of water droplets, dust and debris. Tornadoes can be among the most violent phenomena of all atmospheric storms we experience.

Read more about NSSL's tornado research here.

Where do tornadoes occur?

Tornadoes occur in many parts of the world, including Australia, Europe, Africa, Asia, and South America. Even New Zealand reports about 20 tornadoes each year. Two of the highest concentrations of tornadoes outside the U.S. are Argentina and Bangladesh.

How many tornadoes occur in the U.S. each year?

About 1,200 tornadoes hit the U.S. yearly. Since official tornado records only date back to 1950, we do not know the actual average number of tornadoes that occur each year. Plus, tornado spotting and reporting methods have changed a lot over the last several decades, which means that we are observing more tornadoes that actually happen.

Where is Tornado Alley?

Tornado Alley is a nickname invented by the media to refer to a broad area of relatively high tornado occurrence in the central United States. Various "Tornado Alley" maps look different because tornado occurrence can be measured many ways: by all tornadoes, tornado county-segments, strong and violent tornadoes only, and databases with different time periods.

However, the idea of a "tornado alley" can be misleading. The U.S. tornado threat shifts from the Southeast in the cooler months of the year, toward the southern and central Plains in May and June, and the northern Plains and Midwest during early summer. Tornadoes can occur and have been reported in all fifty states!

Please remember, violent tornadoes do happen outside "Tornado Alley" every year.

When are tornadoes most likely?

Tornado season usually refers to the time of year the U.S. sees the most tornadoes. The peak "tornado season" for the southern Plains (e.g., Texas, Oklahoma, and Kansas) is from May into early June. On the Gulf coast, it is earlier in the spring. In the northern Plains and upper Midwest (North and South Dakota, Nebraska, Iowa, Minnesota), tornado season is in June or July. But, remember, tornadoes can happen at any time of year. Tornadoes can also happen at any time of day or night, but most tornadoes occur between 4-9 p.m.

What is the difference between a Tornado WATCH and a Tornado WARNING?

A Tornado WATCH is issued by the NOAA Storm Prediction Center meteorologists who watch the weather 24/7 across the entire U.S. for weather conditions that are favorable for tornadoes and severe weather. A watch can cover parts of a state or several states. Watch and prepare for severe weather and stay tuned to NOAA Weather Radio to know when warnings are issued.

A Tornado WARNING is issued by your localNOAA National Weather Service Forecast Office meteorologists who watch the weather 24/7 over a designated area. This means a tornado has been reported by spotters or indicated by radar and there is a serious threat to life and property to those in the path of the tornado. A tornado warning indicates that you should ACT NOW to find safe shelter! A warning can cover parts of counties or several counties in the path of danger.

Watchthis Youtube video for a great explanation!

How is tornado strength rated?

To determine the strength of a tornado, experts examine the damage it caused. From this information, we can estimate the wind speeds. An "Enhanced Fujita Scale" was implemented by the National Weather Service in 2007 to rate tornadoes in a more consistent and accurate manner. The EF-Scale takes into account more variables than the original Fujita Scale (F-Scale) when assigning a wind speed rating to a tornado, incorporating 28 damage indicators such as building type, structures and trees. For each damage indicator, there are 8 degrees of damage ranging from the beginning of visible damage to complete destruction of the damage indicator. The original F-scale did not take these details into account. The original F-Scale historical data base will not change. An F5 tornado rated years ago is still an F5, but the wind speed associated with the tornado may have been somewhat less than previously estimated. A correlation between the original F-Scale and the EF-Scale has been developed. This makes it possible to express ratings in terms of one scale to the other, preserving the historical database.

How do tornadoes form?

The truth is that we don't fully understand. The most destructive tornadoes occur from supercells, which are rotating thunderstorms with a well-defined radar circulation called a mesocyclone. (Supercells can also produce damaging hail, severe non-tornadic winds, frequent lightning, and flash floods.) Tornado formation is believed to be dictated mainly by things which happen on the storm scale, in and around the mesocyclone. Recent theories and results from the VORTEX2 program suggest that once a mesocyclone is underway, tornado development is related to the temperature differences across the edge of downdraft air wrapping around the mesocyclone. Mathematical modeling studies of tornado formation also indicate that it can happen without such temperature patterns; and in fact, very little temperature variation was observed near some of the most destructive tornadoes in history on 3 May 1999. We still have lots of work to do.

What do storm spotters look for when trying to identify a tornado or a dangerous storm?

Inflow bands are ragged bands of low cumulus clouds extending from the main storm tower usually to the southeast or south. The presence of inflow bands suggests that the storm is gathering low-level air from several miles away. If the inflow bands have a spiraling nature to them, it suggests the presence of rotation.

Thebeaver's tail is a smooth, flat cloud band extending from the eastern edge of the rain-free base to the east or northeast. It usually skirts around the southern edge of the precipitation area. It also suggests the presence of rotation.

Awall cloud is an isolated cloud lowering attached to the rain-free base of the thunderstorm. The wall cloud is usually to the rear of the visible precipitation area.

A wall cloud that may produce a tornado can exist for 10-20 minutes before a tornado appears, but not always. A wall cloud may also persistently rotate (often visibly), have strong surface winds flowing into it, and may have rapid vertical motion indicated by small cloud elements quickly rising into the rain-free base.

As the storm intensifies, the updraft draws in low-level air from several miles around. Some low-level air is pulled into the updraft from the rain area. This rain-cooled air is very humid; the moisture in the rain-cooled air quickly condenses below therain-free base to form the wall cloud.

Therear flank downdraft (RFD) is a downward rush of air on the back side of the storm that descends along with the tornado. The RFD looks like a "clear slot" or "bright slot" just to the rear (southwest) of the wall cloud. It can also look like curtains of rain wrapping around the cloud base circulation. The RFD causes gusty surface winds that occasionally have embedded downbursts. The rear flank downdraft is the motion in the storm that causes the hook echo feature on radar.

Acondensation funnel is made up of water droplets and extends downward from the base of the thunderstorm. If it is in contact with the ground it is a tornado; otherwise it is a funnel cloud. Dust and debris beneath the condensation funnel confirm a tornado's presence.

Be careful! Tornadoes can form and be in contact with the ground without a fully condensed funnel!

An excellent comprehensive list of questions and answers about tornadoes can be found here:http://www.spc.noaa.gov/faq/tornado/

NSSL is working to simulate storms that produce tornadoes in computer models to better understand how they form and behave.

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Basic information about tornadoes, from the NOAA National Severe Storms Laboratory.

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This article gives a lot of information about hurricanes. If you need more information, you may use another credible website. Just be sure to provide a link to the website you use.

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The National Hurricane Center has a long history of issuing tropical cyclone advisories, with the first known recorded forecast being in 1954, when 24-hour predictions of a storm's track were made. Since then, forecasts have been expanded out in time and added predictions of intensity, size, and associated hazards, such as wind, storm surge, and rainfall.

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The National Hurricane Center has a long history of issuing tropical cyclone advisories, with the first known recorded forecast being in 1954, when 24-hour predictions of a storm's track were made. Since then, forecasts have been expanded out in time and added predictions of intensity, size, and associated hazards, such as wind, storm surge, and rainfall.

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This article gives a lot of information about earthquakes. If you need more information, you may use another credible website. Just be sure to provide a link to the website you use.

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Welcome to DoSomething.org, a global movement of millions of young people making positive change, online and off! The 11 facts you want are below, and the sources for the facts are at the very bottom of the page. After you learn something, Do Something! Find out how to take action here.

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This article gives a lot of information about wildfires. If you need more information, you may use another credible website. Just be sure to provide a link to the website you use.

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Welcome to DoSomething.org, a global movement of millions of young people making positive change, online and off! The 11 facts you want are below, and the sources for the facts are at the very bottom of the page. After you learn something, Do Something! Find out how to take action here.

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Each expert group should answer the questions on this Google Doc about their natural disaster.

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Create a new document and edit with others at the same time -- from your computer, phone or tablet. Get stuff done with or without an internet connection. Use Docs to edit Word files. Free from Google.

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This article gives a lot of information about droughts. If you need more information, you may use another credible website. Just be sure to provide a link to the website you use.

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This article gives a lot of information about floods. If you need more information, you may use another credible website. Just be sure to provide a link to the website you use.

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Severe Weather 101

Flood Basics

What is flooding?

Flooding is an overflowing of water onto land that is normally dry. Floods can happen during heavy rains, when ocean waves come on shore, when snow melts quickly, or when dams or levees break. Damaging flooding may happen with only a few inches of water, or it may cover a house to the rooftop. Floods can occur within minutes or over a long period, and may last days, weeks, or longer. Floods are the most common and widespread of all weather-related natural disasters.

Flash floods are the most dangerous kind of floods, because they combine the destructive power of a flood with incredible speed. Flash floods occur when heavy rainfall exceeds the ability of the ground to absorb it. They also occur when water fills normally dry creeks or streams or enough water accumulates for streams to overtop their banks, causing rapid rises of water in a short amount of time. They can happen within minutes of the causative rainfall, limiting the time available to warn and protect the public.

Where and when do floods occur?

Flooding occurs in every U.S. state and territory, and is a threat experienced anywhere in the world that receives rain. In the U.S. floods kill more people each year than tornadoes, hurricanes or lightning.

What areas are at risk from flash floods?

Densely populated areas are at a high risk for flash floods. The construction of buildings, highways, driveways, and parking lots increases runoff by reducing the amount of rain absorbed by the ground. This runoff increases the flash flood potential.

Sometimes, streams through cities and towns are routed underground into storm drains. During heavy rain, the storm drains can become overwhelmed or plugged by debris and flood the roads and buildings nearby.Low spots, such as underpasses, underground parking garages, basements, and low water crossings can become death traps.

Areas near rivers are at risk from floods. Embankments, known as levees, are often built along rivers and are used to prevent high water from flooding bordering land. In 1993, many levees failed along the Mississippi River, resulting in devastating floods. The city of New Orleans experienced massive devastating flooding days after Hurricane Katrina came onshore in 2005 due to the failure of levees designed to protect the city.

Dam failures can send a sudden destructive surge of water downstream. In 1889 a dam break upstream from Johnstown, Pennsylvania, released a 30-40 foot wall of water that killed 2200 people within minutes.

Mountains and steep hills produce rapid runoff, which causes streams to rise quickly. Rocks and shallow, clayey soils do not allow much water to infiltrate into the ground. Saturated soils can also lead to rapid flash flooding.Camping or recreating along streams or rivers can be a risk if there are thunderstorms in the area. A creek only 6 inches deep in mountainous areas can swell to a 10-foot deep raging river in less than an hour if a thunderstorm lingers over an area for an extended period of time. Sometimes the thunderstorms that produce the heavy rainfall may happen well upstream from the impacted area, making it harder to recognize a dangerous situation.

Very intense rainfall can produce flooding even on dry soil. In the West, mostcanyons, small streams and dry arroyos are not easily recognizable as a source of danger. The causative rainfall can occur upstream of the canyon, and hikers can be trapped by rapidly rising water. Floodwaters can carry fast-moving debris that pose significant risks to life.

Additional high-risk locations includerecent burn areas in mountains, and urban areas from pavement and roofs which enhance runoff.

Ice jams and snowmelt can help cause flash floods. A deep snowpack increases runoff produced by melting snow. Heavy spring rains falling on melting snowpack can produce flash flooding. Melting snowpack may also contribute to floods produced by ice jams on creeks and rivers. Thick layers of ice often form on streams and rivers during the winter. Melting snow and/or warm rain running into the streams may lift and break this ice, allowing large chunks of ice to jam against bridges or other structures. This causes the water to rapidly rise behind the ice jam. If the water is suddenly released, serious flash flooding could occur downstream. Huge chunks of ice can be pushed onto the shore and through houses and buildings.

National Weather Service Messaging Terminology

FLASH FLOOD WATCH or FLOOD WATCH

Flash flooding or flooding is possible within the designated watch area - be alert.

FLASH FLOOD WARNING or FLOOD WARNING

Flash flooding or flooding has been reported or is imminent - take necessary precautions at once! Get to higher ground!

Turn around, don't drown! Most fatalities in the US from flash flooding are from vehicles driving into flooded roadways.

URBAN and SMALL STREAM ADVISORY

Flooding of small streams, streets and low-lying areas, such as railroad underpasses and urban storm drains is occurring.

FLASH FLOOD STATEMENT or FLOOD STATEMENT

Follow-up information regarding a flash flood/flood event.

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Basic information about flooding, from the NOAA National Severe Storms Laboratory.