Tornado emergency

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Large, violent tornadoes can cause catastrophic damage when striking populated areas.

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 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 rare cases, 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]

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 have resulted in very few to no fatalities and, occasionally, have produced damage corresponding to the Fujita Scale's "weak" category (EF0-EF1).

History[edit]

First use[edit]

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.[2]

"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.[3]"

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

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:[4][5]

Evolved usage[edit]

At 3:01 p.m. CDT on May 20, 2013, this bulletin was issued by the National Weather Service Norman forecast office confirming that a destructive tornado was on the ground and headed for Moore and southern portions of Oklahoma City, Oklahoma. Note the differences between this bulletin and the first-ever bulletin from 1999. It should also be noted that this was issued during an updated tornado warning and not in a follow-up severe weather statement. The Moore disaster did claim many lives, but this emergency prevented many more fatalities. The type of tornado, EF5, is a very deadly type, thus this bulletin was issued, with the particularly dangerous situation phrase intended.

Text of the Moore Tornado Emergency from May 20, 2013[edit]

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NORMAN OK
301 PM CDT MON MAY 20 2013

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWESTERN MCCLAIN COUNTY IN CENTRAL OKLAHOMA...
  SOUTHERN OKLAHOMA COUNTY IN CENTRAL OKLAHOMA...
  NORTHERN CLEVELAND COUNTY IN CENTRAL OKLAHOMA...

* UNTIL 345 PM CDT

* AT 259 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS AND STORM
  SPOTTERS WERE TRACKING A LARGE AND EXTREMELY DANGEROUS TORNADO NEAR
  NEWCASTLE. DOPPLER RADAR SHOWED THIS TORNADO MOVING NORTHEAST AT 20
  MPH.

THIS IS A TORNADO EMERGENCY FOR MOORE AND SOUTH OKLAHOMA CITY.

IN ADDITION TO A TORNADO...LARGE DESTRUCTIVE HAIL UP TO TENNIS BALL
SIZE IS EXPECTED WITH THIS STORM.

* LOCATIONS IMPACTED INCLUDE...
  MIDWEST CITY...MOORE...NEWCASTLE...STANLEY DRAPER LAKE...TINKER AIR
  FORCE BASE AND VALLEY BROOK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS AN EXTREMELY DANGEROUS AND LIFE THREATENING SITUATION. IF YOU
CANNOT GET UNDERGROUND GO TO A STORM SHELTER OR AN INTERIOR ROOM OF A
STURDY BUILDING NOW.

TAKE COVER NOW IN A STORM SHELTER OR AN INTERIOR ROOM OF A STURDY
BUILDING. STAY AWAY FROM DOORS AND WINDOWS.
&&

$$

Source:[6]

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

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.[citation needed] 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

Standardization and recent usage[edit]

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, 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.[7][8]

On April 1, 2013, the IBW experiment expanded to include all National Weather Service WFOs within the Central Region;[9] the IBW experiment was expanded again to include eight additional offices within the Eastern, Southern and Western Regions in the spring of 2014.[10] 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,[11] and again on May 31, for portions of eastern Canadian County and western sections of the immediate Oklahoma City area for another tornado.

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[edit]

The National Weather Service Weather Forecast Office in Des Moines 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.[1] 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.

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, 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 (EF-3 or higher) 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.

The Washington, Illinois tornado on November 17, 2013 did not prompt a Tornado Emergency; however, it affected many people. The town of Washington is not populated enough; however, it has a population of approximately 15,000 residents. The National Weather Service in Lincoln may have similar criteria, however.

Tornado safety[edit]

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.[12]

Example of tornado emergency usage[edit]

The audible alert to the right was issued in Sumiton, Alabama, in 2015.


Tornado Warning
GAC081-093-261-051815-
/O.NEW.KFFC.TO.W.0042.170405T1731Z-170405T1815Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service PEACHTREE CITY GA
131 PM EDT WED APR 5 2017

...TORNADO EMERGENCY FOR SOUTHERN DOOLY...SOUTHEAST SUMTER
...AND NORTHWEST CRISP COUNTIES...

The National Weather Service in PEACHTREE CITY has issued a

* Tornado Warning for...
  Southern Dooly County in central Georgia...
  Southeastern Sumter County in west central Georgia...
  Northwestern Crisp County in central Georgia...

* Until 215 PM EDT

* At 128 PM EDT, a confirmed large and destructive tornado was
  observed over Maddox, or near Americus, moving east at 35 mph.

  TORNADO EMERGENCY for SOUTHERN DOOLY...SOUTHEAST SUMTER
...AND NORTHWEST CRISP COUNTIES. This is a
  PARTICULARLY DANGEROUS SITUATION. TAKE COVER NOW!

  HAZARD...Deadly tornado.

  SOURCE...Emergency management confirmed tornado that is now
           likely rain wrapped and difficult to see along with
           a history of producing widespread damage.

  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.

* Locations impacted include...
  Americus, Cordele, Vienna, Leslie, Lilly, De Soto, Desoto, Cobb,
  Sumter, Lamar, Georgia Veterans Memorial St Pk, Richwood,
  Huntington, Drayton, Maddox and Methvins.

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.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

A large and extremely dangerous tornado is on the ground. Take
immediate tornado precautions. This is an emergency situation.

If you see wind damage...hail or flooding...wait until the storm has
passed...and then call the National Weather Service toll free
at 1 8 6 6 7 6 3 4 4 6 6 or tweet us your report at NWSATLANTA.

&&

LAT...LON 3192 8426 3201 8429 3207 8424 3211 8414
      3217 8380 3208 8369 3191 8377 3191 8385
TIME...MOT...LOC 1728Z 263DEG 32KT 3202 8424

TORNADO...OBSERVED
TORNADO DAMAGE THREAT...CATASTROPHIC
HAIL...1.50IN

$$

See also[edit]

References[edit]

  1. ^ a b "Tornado Emergency Media Advisory" (PDF). NWS - Des Moines, Iowa. March 12, 2010. Retrieved 2010-03-29.
  2. ^ "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.
  3. ^ "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.
  4. ^ Mathis, Nancy (2007). "Inside the Bear's Cage". Storm Warning: The Story of a Killer Tornado. Touchstone. p. 129. ISBN 0-7432-8053-9.
  5. ^ "What is a Tornado Emergency?". Weather Forecast Office. Little Rock, Arkansas: National Oceanic and Atmospheric Administration. February 11, 2015. Missing or empty |url= (help); |access-date= requires |url= (help)
  6. ^ National Weather Service, Norman Weather Forecast Office (2013-05-20). "Tornado Warning". Iowa State University Department of Agronomy. Retrieved 2013-05-24.
  7. ^ "Impact Based Warning Experimental Product" (PDF). National Weather Service. Archived from the original (PDF) on January 16, 2014. Retrieved 2012-04-04.
  8. ^ Draper, Bill (2012-04-01). "'UNSURVIVABLE!' New Tornado Warnings Aim to Scare". Yahoo! News and the Associated Press. Retrieved 2012-04-04.
  9. ^ "Impact Based Warning Experimental Product". Crh.noaa.gov. Retrieved 2014-01-22.
  10. ^ National Weather Service (2014). "Impact Based Warnings". National Oceanic and Atmospheric Administration. Retrieved March 12, 2014.
  11. ^ 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.
  12. ^ "The Online Tornado FAQ (by Roger Edwards, SPC)". Spc.noaa.gov. Retrieved 2014-01-22.