Alert archive / Oklahoma / Tornado Warnings in 2017

Tornado Warning 91, NWS Norman, OK

October 21, 2017Caddo County, Comanche County, Oklahoma

NWS Norman, OK issued this tornado warning at Oct 21, 2017, 6:09 PM CDT for Caddo County, Comanche County, Oklahoma. It was in force for 36 min. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Oct 21, 2017, 6:09 PM CDT (23:09 UTC)
Expired
Oct 21, 2017, 6:45 PM CDT
In force
36 min
Issued by
NWS Norman, OK
Area
Storm-based polygon
Tornado
Observed
Hail
2.0 in

Counties Caddo County, OK, Comanche County, OK

The radar

The Altus AFB radar (KFDR), 56 km from the middle of the area, began a volume at 23:10 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Oct 21, 6:10 PM CDTTSTM WND DMG2 W Cache, OKPOWERPOLES PARTIALLY DOWN. TIME ESTIMATED BY RADAR.
Oct 21, 6:19 PM CDTTSTM WND DMG2 W Cache, OKPOWERPOLES PARTIALLY DOWN.
Oct 21, 6:20 PM CDTHAIL 0.88Lake Lawtonka, OK

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Oct 21, 3:06 PM CDTTornado WatchSPC7 hr

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 11.2 hours before the alert went out and 118 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 12:00Z on 2017-10-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 725 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 12:00Z on 2017-10-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 231 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
725 J/kg
Mixed-layer CIN
-149 J/kg
Mixed-layer LCL
642 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
231 m²/s²
0-3 km storm-relative helicity
252 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.8

Open this sounding in Storm Lab

The text

As transmitted.

399 
WFUS54 KOUN 212309
TOROUN
OKC015-031-212345-
/O.NEW.KOUN.TO.W.0091.171021T2309Z-171021T2345Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Norman OK
609 PM CDT SAT OCT 21 2017

The National Weather Service in Norman has issued a

* Tornado Warning for...
  Northwestern Comanche County in southwestern Oklahoma...
  Southwestern Caddo County in southwestern Oklahoma...

* Until 645 PM CDT

* At 609 PM CDT, a confirmed tornado was located over southwestern
  Fort Sill, moving northeast at 35 mph.

  HAZARD...Damaging tornado and hail up to two inches in diameter. 

  SOURCE...Weather spotters confirmed tornado. 

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely. 

* Locations impacted include...
  Cache, Medicine Park, Meers, Lake Lawtonka, southwestern Lake
  Ellsworth, Fort Sill and Wichita Mountains Wildlife Refuge.

This includes Interstate 44 between mile markers 45 and 51.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. TAKE COVER NOW! Move to a
storm shelter, safe room or an interior room on the lowest floor of a
sturdy building. Avoid windows. If you are outdoors, in a mobile
home, or in a vehicle, move to the closest substantial shelter and
protect yourself from flying debris.

&&

LAT...LON 3458 9865 3470 9874 3489 9851 3484 9839
      3474 9832
TIME...MOT...LOC 2309Z 226DEG 30KT 3465 9864 

TORNADO...OBSERVED
HAIL...2.00IN

$$

KURTZ
3 follow-up statements
213 
WWUS54 KOUN 212318
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
618 PM CDT SAT OCT 21 2017

OKC015-031-212345-
/O.CON.KOUN.TO.W.0091.000000T0000Z-171021T2345Z/
Comanche OK-Caddo OK-
618 PM CDT SAT OCT 21 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 645 PM CDT FOR
NORTHWESTERN COMANCHE AND SOUTHWESTERN CADDO COUNTIES...
    
At 618 PM CDT, a severe thunderstorm capable of producing a tornado
was located over western Fort Sill, moving northeast at 35 mph.

HAZARD...Tornado and baseball size hail. 

SOURCE...Radar indicated rotation. 

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely. 

Locations impacted include...
Medicine Park, Lake Lawtonka, Meers, southwestern Lake Ellsworth,
Fort Sill and Wichita Mountains Wildlife Refuge.

This includes Interstate 44 between mile markers 46 and 51.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a storm shelter, safe room, or an interior
room on the lowest floor of a sturdy building. Avoid windows. If you
are outdoors, in a mobile home, or in a vehicle, move to the closest
substantial shelter and protect yourself from flying debris.

&&

LAT...LON 3464 9857 3466 9864 3474 9870 3489 9851
      3484 9839 3475 9833
TIME...MOT...LOC 2318Z 226DEG 30KT 3470 9857 

TORNADO...RADAR INDICATED
HAIL...2.75IN

$$

KURTZ
684 
WWUS54 KOUN 212335
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
635 PM CDT SAT OCT 21 2017

OKC015-031-212345-
/O.CON.KOUN.TO.W.0091.000000T0000Z-171021T2345Z/
Comanche OK-Caddo OK-
635 PM CDT SAT OCT 21 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 645 PM CDT FOR NORTH
CENTRAL COMANCHE AND SOUTHWESTERN CADDO COUNTIES...
    
At 635 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Lake Lawtonka, moving northeast at 25 mph.

HAZARD...Tornado and baseball size hail. 

SOURCE...Radar indicated rotation. 

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely. 

Locations impacted include...
Medicine Park, Lake Lawtonka, Meers, southwestern Lake Ellsworth,
Fort Sill and eastern Wichita Mountains Wildlife Refuge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a storm shelter, safe room, or an interior
room on the lowest floor of a sturdy building. Avoid windows. If you
are outdoors, in a mobile home, or in a vehicle, move to the closest
substantial shelter and protect yourself from flying debris.

&&

LAT...LON 3469 9852 3473 9861 3480 9862 3489 9851
      3484 9839 3478 9835
TIME...MOT...LOC 2335Z 227DEG 23KT 3477 9848 

TORNADO...RADAR INDICATED
HAIL...2.75IN

$$

KURTZ
802 
WWUS54 KOUN 212343
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
643 PM CDT SAT OCT 21 2017

OKC015-031-212352-
/O.EXP.KOUN.TO.W.0091.000000T0000Z-171021T2345Z/
Comanche OK-Caddo OK-
643 PM CDT SAT OCT 21 2017

...THE TORNADO WARNING FOR NORTH CENTRAL COMANCHE AND SOUTHWESTERN
CADDO COUNTIES WILL EXPIRE AT 645 PM CDT...
    
The tornado threat has diminished and the Tornado Warning has been
cancelled. However, large hail and damaging winds remain likely and a
Severe Thunderstorm Warning remains in effect for the area.  However
small hail is still possible with this thunderstorm.

Remember, a Severe Thunderstorm Warning still remains in effect for
Comanche county.

LAT...LON 3469 9852 3473 9861 3480 9862 3489 9851
      3484 9839 3478 9835
TIME...MOT...LOC 2342Z 226DEG 30KT 3481 9843 

$$

KURTZ

The office that day

Everything else NWS Norman, OK issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 21, 3:28 PM CDTSpecial Weather StatementOUNTillman32 min
Oct 21, 3:37 PM CDTSevere Thunderstorm WarningOUNComanche, Jackson, Kiowa, Tillman53 min
Oct 21, 4:04 PM CDTSpecial Weather StatementOUNRoger Mills26 min
Oct 21, 4:05 PM CDTSpecial Weather StatementOUNCuster40 min
Oct 21, 4:06 PM CDTSevere Thunderstorm WarningOUNJackson, Tillman39 min
Oct 21, 4:08 PM CDTSevere Thunderstorm WarningOUNKiowa, Washita52 min
Oct 21, 4:21 PM CDTSpecial Weather StatementOUNBeckham24 min
Oct 21, 4:25 PM CDTSevere Thunderstorm WarningOUNBlaine, Dewey50 min
Oct 21, 4:29 PM CDTSevere Thunderstorm WarningOUNBeckham, Roger Mills46 min
Oct 21, 4:31 PM CDTSevere Thunderstorm WarningOUNDewey, Ellis, Roger Mills44 min
Oct 21, 4:42 PM CDTSevere Thunderstorm WarningOUNComanche, Jackson, Kiowa, Tillman48 min
Oct 21, 4:45 PM CDTSevere Thunderstorm WarningOUNBlaine, Caddo, Canadian, Custer, Kiowa, Washita45 min
Oct 21, 4:48 PM CDTSpecial Weather StatementOUNRoger Mills27 min
Oct 21, 5:09 PM CDTSevere Thunderstorm WarningOUNBeckham, Roger Mills37 min
Oct 21, 5:13 PM CDTSevere Thunderstorm WarningOUNAlfalfa, Garfield, Grant, Major47 min
Oct 21, 5:18 PM CDTSevere Thunderstorm WarningOUNCaddo, Comanche, Jackson, Kiowa, Washita42 min
Oct 21, 5:24 PM CDTSevere Thunderstorm WarningOUNCaddo, Comanche, Kiowa, Tillman51 min
Oct 21, 5:27 PM CDTSevere Thunderstorm WarningOUNJackson, Tillman48 min
Oct 21, 5:28 PM CDTSevere Thunderstorm WarningOUNBlaine, Custer, Dewey47 min
Oct 21, 5:30 PM CDTSevere Thunderstorm WarningOUNCuster, Washita45 min
Oct 21, 5:37 PM CDTSpecial Weather StatementOUNMajor38 min
Oct 21, 5:44 PM CDTTornado WarningOUNComanche, Tillman31 min
Oct 21, 5:49 PM CDTSevere Thunderstorm WarningOUNJackson, Tillman41 min
Oct 21, 5:54 PM CDTSevere Thunderstorm WarningOUNCaddo, Comanche, Kiowa, Washita51 min
Oct 21, 6:09 PM CDTSpecial Weather StatementOUNGarfield, Grant36 min
Oct 21, 6:25 PM CDTSevere Thunderstorm WarningOUNComanche, Kiowa, Tillman50 min
Oct 21, 6:29 PM CDTAreal Flood AdvisoryOUNCaddo, Comanche, Kiowa, Tillman3 hr
Oct 21, 6:33 PM CDTSpecial Weather StatementOUNBlaine27 min
Oct 21, 6:41 PM CDTSpecial Weather StatementOUNKay, Noble34 min
Oct 21, 6:41 PM CDTSevere Thunderstorm WarningOUNCaddo, Comanche, Grady49 min
Oct 21, 6:43 PM CDTAreal Flood AdvisoryOUNGarfield, Grant, Kay, Noble3 hr
Oct 21, 6:50 PM CDTFlash Flood WarningOUNComanche3 hr
Oct 21, 6:55 PM CDTSpecial Weather StatementOUNKingfisher35 min
Oct 21, 6:57 PM CDTSevere Thunderstorm WarningOUNKay, Noble48 min

Nearby

Tornado Warnings in Oklahoma, 2017Every tornado warning in 2017Tornadoes in 2017

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.