Tornado emergency

A tornado emergency is an enhanced version of a tornado warning, which is used by the National Weather Service (NWS) in the United States during imminent, significant tornado occurrences in highly populated areas. Although it is not a new warning type from the NWS, issued instead within a severe weather statement or in the initial tornado warning, a tornado emergency generally means that significant, widespread damage is expected to occur and a high likelihood of numerous fatalities is expected with a large, strong to violent tornado.[1][2]

These enhanced warnings are intended to convey the urgency of the weather situation to the general public, who are advised to take safety precautions immediately if they are in or near the projected path of a large tornado or its accompanying thunderstorm; tornado emergencies are usually identified following the preceding storm summary in the tornado warning product, which itself will denote visual or radar confirmation of "a large and extremely dangerous [or destructive] tornado" that is ongoing; precautionary action statements in the product also recommend that people in the storm's path find shelter in an underground shelter or safe room to protect themselves from the storm, if available.

While many tornadoes observed to be at or larger than ¼-mile in width have been documented to have produced catastrophic damage falling under the "strong" or "violent" categories (EF2–EF5) of the Enhanced Fujita Scale, there have been instances in which tornadoes of this intensity have resulted in very few to no fatalities and, occasionally, have produced damage corresponding to the Enhanced Fujita Scale's "weak" category (EF0–EF1).

History

First use

The term was first used during the May 3, 1999 tornado outbreak that spawned an F5 tornado which struck the municipalities of Bridge Creek and Moore, located just south of Oklahoma City, followed by southern and eastern parts of the city itself, Del City, and Midwest City. On that day, between 5:30 and 6:30 p.m., David Andra, the Science and Operations Officer at the National Weather Service Weather Forecast Office in Norman watched as the large, destructive tornado approached Oklahoma City. This led to the issuance of the first tornado emergency, which in this instance was released as a standalone weather statement issued separately from the original tornado warning.[3]

"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.[4]"

Text of the South Oklahoma City metro Tornado Emergency from May 3, 1999

 
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
657 PM CDT MON MAY 3 1999

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

AT 657 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 715 PM AND 730 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 INDICATED THIS STORM MAY CONTAIN DESTRUCTIVE HAIL TO 
THE SIZE OF BASEBALLS...OR LARGER.

LAT...LON 3524 9784 3511 9769 3536 9735 3552 9754

ANDRA

Source:[5]

Evolved usage

At 5:15 PM CST December 1, 2018, a large tornado was on the ground near Taylorville, Illinois. The National Weather Service in Lincoln felt it necessary to issue a tornado emergency due to the amount of destruction this large tornado was capable of producing. In this case, the tornado emergency was included in the issuance of a tornado warning.

Text of the Taylorville, IL Tornado Emergency

 
799
WFUS53 KILX 012315
TORILX
ILC021-012345-
/O.NEW.KILX.TO.W.0028.181201T2315Z-181201T2345Z/

BULLETIN - EAS ACTIVIATION REQUESTED
Tornado Warning
National Weather Service Lincoln IL
515 PM CST SAT DEC 1 2018

...TORNADO EMERGENCY FOR TAYLORVILLE...

The National Weather Service in Lincoln has issued a

* Tornado Warning for...
  Central Christian County in central Illinois...

* Until 545 PM CST.
* At 514 PM CST, a confirmed large and destructive tornado was 
  observed near Taylorville, moving northeast at 30 mph.

  TORNADO EMERGENCY for Taylorville. This is a PARTICULARLY
  DANGEROUS SITUATION. TAKE COVER NOW!

  HAZARD...Deadly tornado.

  Source...Radar confirmed tornado.

  IMPACT...You are in a life-threatening situation. Flying debris 
           may be deadly to those caught without shelter. Mobile
           homes will be destroyed. Considerable damage to homes,
           businesses, and vehicles is likely and complete
           destruction is possible.

* The tornado will be near...
  Taylorville around 525 PM CST.
  Stonington around 540 PM CST.

Other locations impacted by this tornadic thunderstorm include
Willeys, Taylorville Airport, and Sharpsburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a large, extremely dangerous and potentially deadly
tornado is on the ground. To protect your life, TAKE COVER NOW! Move
to an interior room on the lowest floor of a sturdy building. Avoid
windows. If in a mobile home, a vehicle or outdoors.. Move to the
closest substantial shelter and protect yourself from flying debris.

&&

LAT...LON 3944 8932 3950 8944 8926 3967 8914
      3966 8914 396 8910 3964 8907
TIME...MOT...LOC 2314Z 212DEG 27KT 3950 8934

TORNADO...OBSERVED
TORNADO DAMAGE THREAT...CATASTROPHIC
HAIL...1.00IN

$

Auten

$

Source:[6]

Text of the Kokomo, Indiana Tornado Emergency from August 24, 2016

This tornado, rated EF3, tornado caused severe damage on the south side of Kokomo, Indiana, and was the only tornado emergency in Howard County history, and the second ever tornado emergency issued by the National Weather Service in Indianapolis. The warning again saved Kokomo from many deaths. However, this was in a severe weather statement, not a tornado warning.

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
325 PM EDT WED AUG 24 2016

INC067-242000-
/O.CON.KIND.TO.W.0023.000000T0000Z-160824T2000Z/
HOWARD IN-
325 PM EDT WED AUG 24 2016

...TORNADO EMERGENCY FOR KOKOMO...

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 400 PM EDT FOR EASTERN
HOWARD COUNTY...

AT 324 PM EDT...A CONFIRMED LARGE AND DESTRUCTIVE TORNADO WAS LOCATED
OVER KOKOMO...MOVING EAST AT 30 MPH.

TORNADO EMERGENCY FOR KOKOMO. THIS IS A PARTICULARLY DANGEROUS
SITUATION. TAKE COVER NOW!

HAZARD...DEADLY TORNADO.

SOURCE...LAW ENFORCEMENT CONFIRMED TORNADO.

IMPACT...YOU ARE IN A LIFE-THREATENING SITUATION. FLYING DEBRIS MAY
         BE DEADLY TO THOSE CAUGHT WITHOUT SHELTER. MOBILE HOMES
         WILL BE DESTROYED. CONSIDERABLE DAMAGE TO HOMES...
         BUSINESSES...AND VEHICLES IS LIKELY AND COMPLETE
         DESTRUCTION IS POSSIBLE.

THE TORNADO WILL BE NEAR...
  GREENTOWN AROUND 340 PM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TO REPEAT...A LARGE...EXTREMELY DANGEROUS...AND POTENTIALLY DEADLY
TORNADO IS ON THE GROUND. TO PROTECT YOUR LIFE...TAKE COVER NOW! MOVE
TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING. AVOID
WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR OUTDOORS...MOVE TO THE
CLOSEST SUBSTANTIAL SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS.

A LARGE AND EXTREMELY DANGEROUS TORNADO IS ON THE GROUND. TAKE
IMMEDIATE TORNADO PRECAUTIONS. THIS IS AN EMERGENCY SITUATION.

&&

LAT...LON 4054 8586 4041 8586 4041 8613 4053 8613
      4056 8600 4056 8587
TIME...MOT...LOC 1924Z 265DEG 25KT 4048 8608

TORNADO...OBSERVED
TORNADO DAMAGE THREAT...CATASTROPHIC
HAIL...1.00IN

$

RYAN

Source:[7]

Tornado Emergency Audio Alert

The audible alert to the right was issued in Sumiton, Alabama, in 2010.

Standardization and recent usage

After the original usage for the May 3, 1999 F5 tornado, the term Tornado Emergency was used by other National Weather Service Weather Forecast Offices (WFOs), 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 NWS forecast offices, such as the one serving the Des Moines, Iowa 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 code: SVS) that is used to follow up a tornado warning.

On April 2, 2012, the National Weather Service began an experimental program within its Wichita, Topeka, Springfield, St. Louis and Kansas City/Pleasant Hill offices in Kansas and Missouri called Impact Based Warning (IBW), which allows the respective offices to enhance warning information, such as adding tags to the warning messages which signify the potential damage severity. In regards to tornadoes, the creation of this multi-tiered system resulted in the implementation of an intermediate tornado warning product, a Particularly Dangerous Situation Tornado Warning.[8][9]

On April 1, 2013, the IBW experiment expanded to include all National Weather Service WFOs within the Central Region;[10] the IBW experiment was expanded again to include eight additional offices within the Eastern, Southern and Western Regions in the spring of 2014.[11] Within the span of eleven days, the National Weather Service WFO in Norman issued tornado emergencies for parts of the Oklahoma City metropolitan area and central Oklahoma: first on May 20, 2013 for the EF5 tornado that struck Moore and portions of southern Oklahoma City,[12] and again on May 31, for portions of eastern Canadian County and western sections of the immediate Oklahoma City area for another tornado.

A tornado emergency was issued in the late-night hours of Memorial Day on May 27, 2019 in Dayton, Ohio, with the tornado outbreak that consisted of 15 tornadoes that hit the area, particularly the cities of Trotwood, Ohio, Brookville, Ohio, and Beavercreek, Ohio, which killed an 81-year-old man.

The usage of tornado emergencies to alert major population centers to the imminent threat of a catastrophic tornado impact has also led to the development of the flash flood emergency which is similarly employed when severe flash floods threaten populated areas.

Criteria

The National Weather Service Weather Forecast Office in Des Moines, Iowa is one of the forecast offices to have created a set purpose and criteria for the usage of "tornado emergencies" in tornado warning products, which were made effective on March 12, 2010. According to the Des Moines office, the purpose of the tornado emergency wording is as follows:

  • 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.

Before usage, the following criteria must be met:

  • A large and catastrophic tornado has been confirmed and will continue
  • The tornado will have a high impact
  • The tornado is expected to cause numerous fatalities.

The National Weather Service Weather Forecast Office in Jackson, Mississippi defines a tornado emergency as "an enhanced Tornado Warning that will be issued by NWS Jackson when there is a heightened risk for a killer or violent tornado of EF3 rating or greater."[13] Their criteria for issuing a tornado emergency are:

  • Radar indication of a strong tornado
  • Reliable reports of significant damage or a large tornado
  • Environmental conditions supportive of strong tornadoes, which is usually the case when a Particularly Dangerous Situation Tornado Watch is in effect.

The National Weather Service office in Nashville, Tennessee also created criteria to declare a tornado emergency within a tornado warning statement 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 doing significant damage must be going through a highly populated area
  • Radar must indicate tornadic debris
  • The tornado must be expected to cause significant, widespread damage and loss of life.

Tornado safety
Main article: Tornado preparedness

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, cellar or safe room, as stronger tornadoes (particularly those significant enough to warrant the inclusion of a tornado emergency declaration within a tornado warning) pose a significant risk of major 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 (such as mattresses or blankets), to protect against falling debris in the event that the roof and ceiling collapse.[14]

See also

References
  1. "Tornado Emergency Media Advisory". NWS-Little Rock, Arkansas. Retrieved 2020-03-26.
  2. "Tornado Emergency NWS Definition". NWS. Retrieved 2020-03-26.
  3. "Tornado emergency in south oklahoma city metro area". NWS - Norman, Oklahoma. May 3, 1999. Archived from the original on February 13, 2008. Retrieved 2007-08-13.
  4. "May 3rd, 1999 from the NWS's Perspective". The Southern Plains Cyclone. National Weather Service. 2 (2). Spring 2004. Archived from the original on 2004-11-08. Retrieved 2008-02-15.
  5. "SVS from NWS OKC". Iowa Environmental Mesonet. 2001. Retrieved April 19, 2019.
  6. National Weather Service, Norman Weather Forecast Office (2013-05-20). "Tornado Warning". Iowa State University Department of Agronomy. Retrieved 2013-05-24.
  7. National Weather Service in Indianapolis, Indiana (2013-05-20). "Tornado Warning". Iowa State University. Retrieved 2020-03-26.
  8. "Impact Based Warning Experimental Product" (PDF). National Weather Service. Archived from the original (PDF) on January 16, 2014. Retrieved 2012-04-04.
  9. Draper, Bill (2012-04-01). "'UNSURVIVABLE!' New Tornado Warnings Aim to Scare". Yahoo! News and the Associated Press. Retrieved 2012-04-04.
  10. "Impact Based Warning Experimental Product". Crh.noaa.gov. Retrieved 2014-01-22.
  11. National Weather Service (2014). "Impact Based Warnings". National Oceanic and Atmospheric Administration. Retrieved March 12, 2014.
  12. Howell, George (2013-05-21). "Okla. Medical Examiner preparing for '40 more bodies' | National News - KCCI Home". Kcci.com. Archived from the original on 2014-01-16. Retrieved 2014-01-22.
  13. US Department of Commerce, NOAA. "NWS Jackson, MS Product Guide--Severe Weather Products". www.weather.gov. Retrieved 2020-01-03.
  14. "The Online Tornado FAQ (by Roger Edwards, SPC)". Spc.noaa.gov. Retrieved 2014-01-22.
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