Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 784, NWS Norman, OK

August 11, 2017Alfalfa County, Grant County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Aug 11, 2017, 1:43 AM CDT for Alfalfa County, Grant County, Oklahoma. It was in force for 47 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 11, 2017, 1:43 AM CDT (06:43 UTC)
Expired
Aug 11, 2017, 2:30 AM CDT
In force
47 min
Issued by
NWS Norman, OK
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Alfalfa County, OK, Grant County, OK

The radar

The Vance AFB radar (KVNX), 8 km from the middle of the area, began a volume at 06:47 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.

The nearest sounding before it

Dodge City, (KDDC), launched 00:00Z, 6.7 hours before the alert went out and 187 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, Dodge City, at 00:00Z on 2017-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 585 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, Dodge City, at 00:00Z on 2017-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 200 square meters per square second.19395878Sfc1 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
585 J/kg
Mixed-layer CIN
-84 J/kg
Mixed-layer LCL
1169 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
200 m²/s²
0-3 km storm-relative helicity
401 m²/s²
Significant tornado parameter
0.5
Supercell composite
8.7

Open this sounding in Storm Lab

The text

As transmitted.

626 
WUUS54 KOUN 110643
SVROUN
OKC003-053-110730-
/O.NEW.KOUN.SV.W.0784.170811T0643Z-170811T0730Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Norman OK
143 AM CDT FRI AUG 11 2017

The National Weather Service in Norman has issued a

* Severe Thunderstorm Warning for...
  Northeastern Alfalfa County in northwestern Oklahoma...
  Western Grant County in northern Oklahoma...

* Until 230 AM CDT

* At 143 AM CDT, a severe thunderstorm was located near Great Salt
  Plains Lake, moving east at 30 mph.

  HAZARD...60 to 65 mph wind gusts and penny size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to roofs, siding, and trees. 

* Locations impacted include...
  Cherokee, Wakita, Nash, Amorita, Byron, Ingersoll, Great Salt
  Plains Lake and Driftwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3676 9845 3696 9837 3691 9779 3660 9783
TIME...MOT...LOC 0643Z 289DEG 28KT 3679 9821 

HAIL...0.75IN
WIND...60MPH
 
$$

SIX
1 follow-up statement
551 
WWUS54 KOUN 110714
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
214 AM CDT FRI AUG 11 2017

OKC003-053-110730-
/O.CON.KOUN.SV.W.0784.000000T0000Z-170811T0730Z/
Alfalfa OK-Grant OK-
214 AM CDT FRI AUG 11 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 230 AM CDT
FOR NORTHEASTERN ALFALFA AND WESTERN GRANT COUNTIES...

At 214 AM CDT, a severe thunderstorm was located 7 miles west of Pond
Creek, moving southeast at 35 mph.

HAZARD...60 mph wind gusts. 

SOURCE...Radar indicated. 

IMPACT...Expect damage to roofs, siding, and trees. 

Locations impacted include...
Cherokee, Wakita, Nash, Amorita, Byron, Ingersoll, Great Salt Plains
Lake and Driftwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3676 9845 3696 9837 3691 9779 3660 9783
TIME...MOT...LOC 0714Z 298DEG 28KT 3670 9793 

HAIL...<.75IN
WIND...60MPH
 
$$

SIX

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 10, 7:03 PM CDTSpecial Weather StatementOUNKay27 min
Aug 10, 7:10 PM CDTSevere Thunderstorm WarningOUNKay50 min
Aug 10, 7:23 PM CDTSevere Thunderstorm WarningOUNMcClain32 min
Aug 10, 7:31 PM CDTSpecial Weather StatementOUNKay29 min
Aug 10, 9:13 PM CDTSpecial Weather StatementOUNGreer32 min
Aug 10, 9:19 PM CDTSpecial Weather StatementOUNRoger Mills26 min
Aug 10, 10:00 PM CDTSpecial Weather StatementOUNBeckham45 min
Aug 10, 10:14 PM CDTSpecial Weather StatementOUNBeckham46 min
Aug 10, 10:44 PM CDTSpecial Weather StatementOUNCuster46 min
Aug 10, 10:45 PM CDTSpecial Weather StatementOUNBeckham45 min
Aug 10, 10:51 PM CDTSpecial Weather StatementOUNHarper39 min
Aug 10, 11:31 PM CDTSpecial Weather StatementOUNCuster29 min
Aug 10, 11:39 PM CDTSpecial Weather StatementOUNEllis36 min
Aug 10, 11:52 PM CDTAreal Flood AdvisoryOUNEllis, Harper, Woodward3 hr
Aug 10, 11:53 PM CDTAreal Flood AdvisoryOUNEllis, Harper, Woodward3 hr
Aug 10, 11:53 PM CDTSevere Thunderstorm WarningOUNBeckham, Custer, Roger Mills, Washita52 min
Aug 11, 12:08 AM CDTAreal Flood AdvisoryOUNBeckham, Roger Mills3 hr
Aug 11, 12:25 AM CDTSpecial Weather StatementOUNRoger Mills35 min
Aug 11, 12:30 AM CDTSpecial Weather StatementOUNWoodward30 min
Aug 11, 12:57 AM CDTAreal Flood AdvisoryOUNWoods3 hr
Aug 11, 1:03 AM CDTSpecial Weather StatementOUNAlfalfa27 min
Aug 11, 1:13 AM CDTFlash Flood WarningOUNBeckham, Custer, Roger Mills, Washita3 hr
Aug 11, 1:18 AM CDTSpecial Weather StatementOUNBeckham27 min
Aug 11, 1:22 AM CDTFlood WatchOUNAlfalfa, Atoka, Beckham, Blaine, Bryan, Caddo and 42 more54 hr
Aug 11, 1:26 AM CDTAreal Flood AdvisoryOUNBlaine3 hr
Aug 11, 1:31 AM CDTSpecial Weather StatementOUNAlfalfa29 min
Aug 11, 1:48 AM CDTFlash Flood WarningOUNAlfalfa, Grant, Woods, Woodward3 hr
Aug 11, 2:29 AM CDTAreal Flood AdvisoryOUNBlaine, Caddo, Canadian, Custer, Washita3 hr
Aug 11, 2:44 AM CDTFlash Flood WarningOUNCaddo, Canadian, Grady4 hr
Aug 11, 2:46 AM CDTFlash Flood WarningOUNGrant, Kay3 hr
Aug 11, 3:25 AM CDTSpecial Weather StatementOUNGrady35 min
Aug 11, 3:49 AM CDTSpecial Weather StatementOUNGarvin26 min
Aug 11, 4:06 AM CDTAreal Flood AdvisoryOUNCanadian, Cleveland, Grady, McClain3 hr
Aug 11, 4:32 AM CDTSpecial Weather StatementOUNCarter, Murray, Pontotoc, Seminole28 min
Aug 11, 6:00 AM CDTAreal Flood AdvisoryOUNComanche, Cotton, Garvin, Grady, Stephens3 hr

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2017Every severe thunderstorm warning 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.