A Tornado Emergency is enhanced wording of tornado warning

Tornado warning

A tornado warning is an alert issued by government weather services to warn that severe thunderstorms with tornadoes may be imminent. It can be issued after a tornado or funnel cloud has been spotted by eye, or more commonly if there are radar indications of tornado formation...

s used by the National Weather Service

National Weather Service

The National Weather Service , once known as the Weather Bureau, is one of the six scientific agencies that make up the National Oceanic and Atmospheric Administration of the United States government...

 (NWS) in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 during significant tornado

Tornado

A tornado is a violent, dangerous, rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. They are often referred to as a twister or a cyclone, although the word cyclone is used in meteorology in a wider...

 occurrences in highly populated areas. Although not a new warning type from the NWS, instead issued in a Severe Weather Statement (or in rare cases, in the initial Tornado Warning), a Tornado Emergency generally means that significant, widespread damage is expected to continue and a high likelihood of numerous fatalities is expected with a large, strong to violent tornado.

It is noted that there are instances where very few to no fatalities have resulted from strong to violent tornadoes (rated EF2-EF5 on the Enhanced Fujita Scale

Enhanced Fujita Scale

The Enhanced Fujita Scale rates the strength of tornadoes in the United States based on the damage they cause.Implemented in place of the Fujita scale introduced in 1971 by Ted Fujita, it began operational use on February 1, 2007. The scale has the same basic design as the original Fujita scale:...

), and not all tornadoes of at least ¼-mile in width produce catastrophic damage (though this is often assumed to be the case). Regardless, people in the path of a large tornado must take immediate safety precautions.

First use

The term was first used during the May 3, 1999 tornado outbreak that spawned the Moore F5 tornado just south of Oklahoma City

Oklahoma city

Oklahoma City is the capital and largest city of the U.S. state of Oklahoma.Oklahoma City may also refer to:*Oklahoma City metropolitan area*Downtown Oklahoma City*Uptown Oklahoma City*Oklahoma City bombing*Oklahoma City National Memorial...

. On that day, between 5:30 and 6:30 p.m., David Andra, the Science and Operations Officer at the National Weather Service

National Weather Service

The National Weather Service , once known as the Weather Bureau, is one of the six scientific agencies that make up the National Oceanic and Atmospheric Administration of the United States government...

 Norman office watched as a large, destructive tornado approached Oklahoma City. This led to the issuance of the first tornado emergency.

"As the large tornado approached western sections of the OKC metro area, we asked ourselves more than once, 'Are we doing all we can do to provide the best warnings and information?' It became apparent that unique and eye-catching phrases needed to be included in the products. At one point we used the phrase 'Tornado Emergency' to paint the picture that a rare and deadly tornado was imminent in the metro area. We hoped that such dire phrases would prompt action from anyone that still had any questions about what was about to happen."

Text of the Moore Tornado Emergency

...TORNADO EMERGENCY IN SOUTH OKLAHOMA CITY METRO AREA...



AT 6:57 PM CDT...A LARGE TORNADO WAS MOVING ALONG INTERSTATE 44 WEST OF

NEWCASTLE. ON ITS PRESENT PATH...THIS LARGE DAMAGING TORNADO WILL

ENTER SOUTHWEST SECTIONS OF THE OKLAHOMA CITY METRO AREA BETWEEN 7:15

AND 7:30 PM. PERSONS IN MOORE AND SOUTH OKLAHOMA CITY SHOULD TAKE

IMMEDIATE TORNADO PRECAUTIONS!



THIS IS AN EXTREMELY DANGEROUS AND LIFE THREATENING SITUATION. IF YOU

ARE IN THE PATH OF THIS LARGE AND DESTRUCTIVE TORNADO...TAKE COVER

IMMEDIATELY.



DOPPLER RADAR HAS INDICATED THIS STORM MAY CONTAIN DESTRUCTIVE HAIL TO THE

SIZE OF BASEBALLS...OR LARGER.

Source:

Standardization and recent usage

After the original usage for the Moore, OK, tornado in 1999, the term Tornado Emergency was used by other NWS offices, although no uniform criteria existed and the issuance was entirely at the discretion of the forecaster issuing the warnings. Usage of the term varied from simply confirmed tornadoes in populated areas to significant, rare tornadoes causing severe damage and injuries. Some National Weather Service

National Weather Service

The National Weather Service , once known as the Weather Bureau, is one of the six scientific agencies that make up the National Oceanic and Atmospheric Administration of the United States government...

 forecast offices, such as the one serving the Des Moines, IA Metropolitan Area, have created standardized criteria and purpose for the usages of the heightened wording. Because data about the tornado and its exact path are often ascertained after the initial tornado warning is issued, this designation is usually added to the Severe Weather Statement (SAME

Specific Area Message Encoding

Specific Area Message Encoding or SAME is the protocol used to encode the Emergency Alert System and NOAA Weather Radio's SAME Public Warning System in the U.S...

 code: SVS) that is used to follow-up a tornado warning.

Criteria

National Weather Service

National Weather Service

The National Weather Service , once known as the Weather Bureau, is one of the six scientific agencies that make up the National Oceanic and Atmospheric Administration of the United States government...

 Des Moines is one of the forecast offices that has created a set purpose and criteria to the usage of "Tornado Emergency" in Tornado Warning products, which they made effective on March 12, 2010. According to their office, the purpose of the tornado emergency wording is:

• To motivate and provide a sense of urgency to persons in the path of this storm to take immediate shelter in a reinforced structure that offers maximum protection from destructive winds.
• To communicate to state, local, and county officials and emergency responders that they should prepare for immediate search and rescue operations.
• To communicate the need to prepare for immediate medical emergencies, evacuation measures, and emergency sheltering.

And before usage, the following criteria must be met:

• A large and catastrophic tornado has been confirmed and will continue (a radar signature alone is not sufficient).
• The tornado will have a high impact and/or affect a highly vulnerable population (estimated to be once every 10 years for central Iowa).
• The tornado is expected to cause numerous fatalities.

The National Weather Service office in Nashville, TN also created criteria for the usage of tornado emergency effective January 1, 2011. It states, "Tornado Emergency can be inserted in the third bulletin of the initial tornado warning (TOR) or in a severe weather statement (SVS)." Before the phrase can be used:

• a confirmed large tornado must be going through a highly populated area such as Metro Nashville
• a violent tornado with a significant damage history
• a confirmed tornado, radar shows evidence of debris
• the confirmed tornado is expected to cause significant widespread damage and loss of life.

Tornado safety

It is recommended that people in the path of a large and violent tornado, whether referenced in a Tornado Warning or a Tornado Emergency, seek shelter in a basement

Basement

__FORCETOC__A basement is one or more floors of a building that are either completely or partially below the ground floor. Basements are typically used as a utility space for a building where such items as the furnace, water heater, breaker panel or fuse box, car park, and air-conditioning system...

, cellar or safe room, as more violent tornadoes pose a significant risk of very serious injury or death for people above ground level. Those who do not have below-ground shelter are still advised to take cover in a room in the center of the home on the lowest floor, and cover themselves with some type of thick padding (mattress, blankets, etc.), to protect against falling debris in the event the roof and ceiling collapse.

Example of tornado emergency usage

SEVERE WEATHER STATEMENT

NATIONAL WEATHER SERVICE JACKSON MS

1203 PM CDT SAT APR 24 2010



...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1230 PM CDT FOR CENTRAL

YAZOO COUNTY...



...THIS IS A TORNADO EMERGENCY FOR THE WARNED AREA...



AT 1203 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS AND STORM

SPOTTERS WERE TRACKING A LARGE AND EXTREMELY DANGEROUS WEDGE

TORNADO.  THIS TORNADO WAS LOCATED 6 MILES NORTH OF SATARTIA MOVING

NORTHEAST AT 60 MPH.



THE TORNADO WILL BE NEAR...

  YAZOO CITY AND LITTLE YAZOO BY 1210 PM CDT...

  MYRLEVILLE BY 1215 PM CDT...

  BENTON AND EDEN BY 1220 PM CDT...

  MIDWAY BY 1225 PM CDT...



PRECAUTIONARY/PREPAREDNESS ACTIONS...



A TORNADO WARNING MEANS THAT A TORNADO IS OCCURRING OR IMMINENT. YOU

SHOULD ACTIVATE YOUR TORNADO ACTION PLAN AND TAKE PROTECTIVE ACTION

NOW. SIGNIFICANT DAMAGE HAS OCCURRED WITH THIS SIGNIFICANT TORNADO!



THIS IS AN EXTREMELY DANGEROUS AND SERIOUS LIFE THREATENING

SITUATION. THIS STORM IS CAPABLE OF PRODUCING STRONG TO VIOLENT

TORNADOES. IF YOU ARE IN THE PATH OF THIS TORNADO...TAKE COVER

IMMEDIATELY!



A TORNADO WATCH REMAINS IN EFFECT UNTIL 800 PM CDT SATURDAY EVENING

FOR MISSISSIPPI.