(Yes, you will be tested!)
SEVERE WEATHER DEFINITIONS
YOU NEED TO KNOW
TYPES OF STORMS
A large organized storm with winds over 74 mph. While the position of a hurricane means where the eye is, hurricane force winds extend out anywhere from 20 to 200 miles away from the center. Tropical storm level winds can go out up to 300 miles. If a hurricane strikes the coast at a certain town, damage will be experienced from 80 to 200 miles to all sides. Rainfall amounts over entire states often exceed 12-18 inches within 2 or 3 days, causing massive flooding. In addition, numerous tornadoes are commonly spawned by hurricanes and tropical storms.
- Tropical Storm
An organized storm with winds between 39 and 73 mph. In addition, there is usually heavy rains that cause flooding. This is still enough to cause significant damage and heavy flooding!! Other than less intense winds, tropical storms bring the same effects as hurricanes including massive amounts of rains, tornadoes, storm surges and extremely rough seas.
Violent storms that often hit with little warning and destroy everything they touch. Winds in "normal" tornadoes we see in Florida are typically only about 100 mph (F0 or F1 intensity... the two weakest categories, producing broken trees, overturned mobile homes, etc.) Tornadoes spawned from hurricanes are MUCH stronger... often closer to F3 strength, meaning they can take out entire neighborhoods.
To ignore the technical differences, essentially a tornado over water. Can ruin a boater's day. Also can move over land and become a tornado. A tornadic waterspout is a tornado over water that can be very strong, while a true waterspout is actually somewhat different and much weaker (like an F0 tornado.)
- Severe Thunderstorm
A severe thunderstorm has some combination (often all) of the following: winds over 58 mph, large (greater than 3/4 inch) hail, intense lightning, intense blinding rain, and they often produce tornadoes (or tornadic waterspouts if over water) with little or no warning. Severe thunderstorms are often found within feeder bands of hurricanes and tropical storms.
STORM FEATURES & SIDE EFFECTS
The center of a hurricane or tropical storm. This is the part whose position is tracked, however the winds and rains extend out from the eye for hundreds of miles! The actual eye is from 10-35 miles wide and is calm and dry within, although the highest winds are in the eye wall. If the eye hits you, you will experience the very worst winds (and rain, usually) of the entire storm on each side of it!!!
- Feeder Bands
The spiral-shaped squall lines of the hurricane. These are where the thunderstorm lines are located. The feeder bands rotate counterclockwise around the eye and extend out for hundreds of miles.
- Storm Surge
A mound of ocean water that rises near the eye of the hurricane. Typical ocean tides go up or down 1-2 feet, while a storm surge often gets to be 8-12 feet... enough to wash inland for many miles, flooding all in its path and simply washing buildings, cars, and people away. This is why coastal areas are evacuated early. Essentially like a tsunami (tidal wave) in destructive power, except it lasts longer. This is added to the tides, and becomes even worse when the storm surge hits at the same time as high tide.
Hurricanes, tropical storms and thunderstorms are classified by CONSTANT winds. Gusts may be much higher. A hurricane with steady winds of 100 mph may contain gusts up to 130 mph.
- Flash Flooding
Floods caused by sudden and intense rain often associated with hurricanes, tropical storms and thunderstorms. Can cause death and destruction... never underestimate the power of water... it will win!!
- Storm Track
The path of the eye of the storm. Remember, hurricane and/or tropical storm force winds extend anywhere from 20 to 300 miles away from the eye!!!
- Hurricane Party
What people do to dramatically increase their chances of dying while being too drunk to notice it.
WATCHES, WARNINGS, ADVISORIES AND STATEMENTS
- Hurricane Watch
Winds greater than 74 mph may hit the area within 36 hours.
- Hurricane Warning
Winds greater than 74 mph probably will to hit the area within 24 hours.
- Tropical Storm Watch
Winds from 39 to 73 mph may hit the area within 36 hours.
- Tropical Storm Warning
Winds from 39 to 73 mph probably will to hit the area within 24 hours. Usually issued for areas to either side of the Hurricane Warning area.
- Tornado Watch
Conditions are ripe for tornadoes within the watch area. Tornados associated with hurricanes and tropical storms are typically a very significant cause of death and damage.
- Tornado Warning
A tornado has actually been spotted visually or on radar. Usually issued for a county. If a tornado WARNING is issued where you live, GET TO THE MIDDLE OF THE LOWEST FLOOR OF A STRONG BUILDING IMMEDIATELY!!! Your life depends on it!!
- Severe Thunderstorm Watch
Conditions are ripe for severe thunderstorms within the watch area.
- Severe Thunderstorm Warning
There is a severe thunderstorm in or heading for the warned area. Treat this like a tornado warning!!
- Flash Flood Watch
Flash floods are likely to occur in the near future. Be alert for rising water and be prepared to have to move to high ground.
- Flash Flood Warning
Flash floods are occurring or expected to occur in the near future. If this happens, get to high ground immediately, and GET AWAY FROM VEHICLES... it only takes 18 inches of water to sweep a car or truck away!
- High Wind Advisory
Windy conditions may occur in the advisory area. This usually makes for unsafe conditions while driving, especially in (but not limited to) large vehicles. Also, avoid boating anywhere in the advisory area.
- High Wind Warning
Very strong winds are expected or already are occuring that present a significant danger while driving, boating and other outdoor activities. Often issued near tropical storms and hurricanes.
- Special Marine Warning
Warnings of interest to boaters, usually because of rough conditions, squall lines, waterspouts,
- Hurricane or Tropical Storm Statement
Statements issued periodically by the National Hurricane Center with an overview of the current situation.
WHO DOES WHAT??
National Oceanic and Atmospheric Administration - the government agency that oversees the various weather-related bureaus and offices.
National Weather Service - The division of NOAA that is responsible for tracking and warning about weather events, usually NOT including tornado watches and hurricane advisories, which typically are issued from the NSSL and Hurricane Center respectively. However, regional NWS offices often issue warnings and some types of watches related to severe weather, and work closely with the Hurricane Center and NSSL to provide timely information and warnings to the public about any weather concerns within their area.
- National Hurricane Center
NOAA office in Miami, FL that tracks and issues advisories on all tropical weather systems.
National Severe Storms Laboratory - NOAA Office in Oklahoma City, KS which issues tornado watches and attempts to predict tornado activity beforehand. (Tornado warnings are usually issued by local NWS offices when possible tornadoes are detected.)
- Voluntary evacuation
This means that it is a good idea to leave to assure your safety. This is usually issued for areas that are expected to suffer major street flooding or that will be unusually hard to reach after the storm (islands, etc.)
- Mandatory evacuation
They won't haul you off in handcuffs if you don't go, but they usually make you sign a form listing your next of kin. This is because staying means that you will probably die. This is usually issued for coastal areas and barrier islands that are likely to be underwater from the storm surge and/or become totally isolated due to bridges to these areas becoming impassable.
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Hits since Sept. 16, 1998