Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 321, NWS Norman, OK

May 16, 2017Alfalfa County, Grant County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at May 16, 2017, 11:56 PM CDT for Alfalfa County, Grant County, Oklahoma. It was in force for 49 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: May 16, 2017, 11:56 PM CDT (04:56 UTC)
Expired: May 17, 2017, 12:45 AM CDT
In force: 49 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Hail: 0.88 in
Wind: 60.0 mph

Counties Alfalfa County, OK, Grant County, OK

The radar

The Vance AFB radar (KVNX), 15 km from the middle of the area, began a volume at 04:57 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

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

Issued	Product	Office	Lasted
May 16, 10:07 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 4.9 hours before the alert went out and 185 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 768 J/kg
Mixed-layer CIN: -307 J/kg
Mixed-layer LCL: 953 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 232 m²/s²
0-3 km storm-relative helicity: 308 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

As transmitted.

413 
WUUS54 KOUN 170456 RRA
SVROUN
OKC003-053-170545-
/O.NEW.KOUN.SV.W.0321.170517T0456Z-170517T0545Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Norman OK
1156 PM CDT TUE MAY 16 2017

The National Weather Service in Norman has issued a

* Severe Thunderstorm Warning for...
  East central Alfalfa County in northwestern Oklahoma...
  Northwestern Grant County in northern Oklahoma...

* Until 1245 AM CDT

* At 1156 PM CDT, a severe thunderstorm was located near Great Salt
  Plains Lake, moving northeast at 30 mph.

  HAZARD...60 mph wind gusts and nickel size hail. 

  SOURCE...Radar indicated. 

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

* Locations impacted include...
  Cherokee, Wakita, Jet, Nash and Great Salt Plains Lake. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3677 9778 3660 9824 3674 9837 3700 9796
      3700 9779
TIME...MOT...LOC 0456Z 238DEG 27KT 3672 9824 

HAIL...0.88IN
WIND...60MPH
 
$$

MAHALE

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Norman, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at May 16, 7:49 PM CDT, 4 hours 7 minutes earlier.

Area forecast discussion, May 16, 7:49 PM CDT, 4 hours 7 minutes before

Area Forecast Discussion
National Weather Service Norman OK
749 PM CDT Tue May 16 2017

...UPDATE...

&&

.DISCUSSION...
Three intense supercells continue moving east-northeast across
western Oklahoma. Low levels continue to gradually stabilize with
growing CIN. As MLCIN increases, low-level shear will continue to
strengthen so the tornado threat will continue for at least a
couple more hours. A local extension of the Tornado Watch to
include Blaine and Caddo will be transmitted shortly.

Large scale forcing for ascent with approaching shortwave trough
is evident in the three water vapor channels from GOES-R. In
response, convection should increase markedly from western north
Texas southward into the Permian Basin. These storms should grow
upscale and move through much of the area overnight with at least
marginally severe wind/hail potential.

Evolution of ongoing supercells to the north is a little unclear
at the moment. Although the tornado threat should lessen as the
boundary layer stabilizes, intense mesoscyclones may persist
resulting in a significant hail and secondary wind threat until
storm intensity decreases and/or consolidation occurs.

BRB

&&

.PREV DISCUSSION... /issued 616 PM CDT Tue May 16 2017/

AVIATION...
Isolated severe storms entering western Oklahoma may pass near
western TAF sites. Later tonight, after 3z, a line of storms is
expected to form and march eastward through the area, eventually
affecting most TAF sites. Ceilings will continue to bounce between
MVFR and VFR into the evening before clearing out with the
approaching convection. Winds will remain southerly and gusty.

Day

PREV DISCUSSION... /issued 216 PM CDT Tue May 16 2017/

DISCUSSION...
We are getting the package out early as things will start getting
busy before too long. As as been discussed for days, a severe
weather event is setting up for this evening, and storms have
already formed on the dryline in the Texas panhandle. Expected
isolated to widely scattered storms along the dryline this evening
moving into western sections of the area. Supercells will be
likely. The airmass will be conducive to tornado potential as
well, especially in the far west. High-resolution models weaken
these storms by mid-late evening as they move northeast, but am
somewhat skeptical how fast these initial storms will diminish.
Regardless, also expect a second wave of storms to form out west
in the mid-late evening. This wave of storms will likely be more
widespread and perhaps become a linear system as they spread east
and northeast. Severe weather will continue to be possible with
these storms overnight.

We will see a break in the thunderstorm activity on Wednesday as
the initial wave moves northeast of the area. But alas, this
respite will be short-lived as the next longwave trough approaches
the area. Severe storms will again be possible Thursday and
Friday. The cold front associated with this system moves through
the area overnight Friday night and Saturday morning with cooler
weather moving in. But the we will continue to have broad
troughing in the Plains, so precipitation chances will persist
into next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  80  63  83  63 /  10  70  10  10
Hobart OK         81  59  86  58 /  30  70   0   0
Wichita Falls TX  84  63  89  64 /  20  70   0   0
Gage OK           82  57  82  55 /  50  50   0   0
Ponca City OK     81  64  83  61 /  20  60  20   0
Durant OK         83  68  86  70 /  10  50  20  10

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...None.
TX...None.
&&

30/10

Hazardous weather outlook, May 16, 9:45 PM CDT, 2 hours 11 minutes before

Hazardous Weather Outlook
National Weather Service Norman OK
945 PM CDT Tue May 16 2017

OKZ004>048-050>052-TXZ083>090-171715-
Harper-Woods-Alfalfa-Grant-Kay-
Ellis-Woodward-Major-Garfield-Noble-Roger Mills-Dewey-Custer-Blaine-
Kingfisher-Logan-Payne-Beckham-Washita-Caddo-Canadian-Oklahoma-
Lincoln-Grady-McClain-Cleveland-Pottawatomie-Seminole-Hughes-Harmon-
Greer-Kiowa-Jackson-Tillman-Comanche-Stephens-Garvin-Murray-
Pontotoc-
Coal-Cotton-Jefferson-Carter-Johnston-Atoka-Love-Marshall-Bryan-
Hardeman-Foard-Wilbarger-Wichita-Knox-Baylor-Archer-Clay-
945 PM CDT Tue May 16 2017

This hazardous weather outlook is for portions of northern...
western...central...and southern Oklahoma...and western north
Texas.

.DAY ONE...Tonight...

.Thunderstorms...
There is a enhanced risk for severe thunderstorms for portions of
western Oklahoma and western sections of north Texas overnight.
There is also a slight risk over central sections of Oklahoma and
parts of western north Texas.

Location... The enhance risk is west of a line from Cherokee to
Watonga to Fort Cobb to Cache and Granfield Oklahoma to Archer City
Texas.

East of the enhanced risk area, there are slight risk of severe
weather west of a line from Chandler to Pauls Valley to Marietta.

There is a marginal risk of severe storms across southeast
Oklahoma.

Timing...
The most likely time for severe weather is through sunrise
Wednesday morning.

Impacts...
Hail up the size of tennis balls and thunderstorm wind gusts over
70 mph will be the primary threats. Tornadoes will also be
possible, especially across the enhanced risk area of western
Oklahoma and western north Texas.

Discussion...
A broken line of severe thunderstorms will move across much of
Oklahoma and western north Texas overnight. This line of storms will
be capable of producing damaging winds and large hail. A few brief,
weak tornadoes will be possible with this activity.

Spotter and Emergency Management Statement...
Storm spotter groups and emergency management personnel across
western and central Oklahoma and adjacent parts of north Texas
should prepare for severe weather operations overnight.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday...

.Thunderstorms...
Thunderstorms may linger across parts of southeast Oklahoma into the
morning hours Wednesday before moving out of the area.

Storm chances return on Thursday and will persist at times through
the weekend and into Monday. Severe weather will be possible
Thursday and Friday.

.Heavy Rainfall...
There is a potential for high rain totals late Thursday through
Friday night, mainly over south-central and southeast Oklahoma. If
you live in an area that is prone to flash flooding, pay close
attention to the forecasts and warnings later this week.

Get graphics and more details at weather.gov/norman...and follow
our weather forecast office on Twitter and Facebook.

In the hours before

Local storm report, May 16, 10:05 PM CDT, 1 hour 51 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1005 PM CDT TUE MAY 16 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1002 PM     TSTM WND GST     3 N ROOSEVELT           34.90N 99.02W
05/16/2017  E60 MPH          KIOWA              OK   STORM CHASER

&&

JP

Special weather statement, May 16, 10:07 PM CDT, 1 hour 49 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
1007 PM CDT TUE MAY 16 2017

OKZ022-035-170345-
Kiowa OK-Washita OK-
1007 PM CDT TUE MAY 16 2017

...SIGNIFICANT WEATHER ADVISORY FOR northeastern Kiowa and eastern
Washita Counties Until 1045 PM CDT...

AT 1007 PM CDT, strong thunderstorms were along a line extending from
3 miles east of Cloud Chief to near Tom Steed Reservoir, moving north
at 45 MPH.

HAZARDS INCLUDE...
Hail up to one-half inch diameter...
Wind gusts over 50 MPH...

LAT...LON 3512 9900 3512 9897 3513 9899 3547 9886
      3546 9862 3538 9862 3475 9887 3477 9913
TIME...MOT...LOC 0307Z 195DEG 39KT 3524 9878 3481 9899

..speg.

Special weather statement, May 16, 11:04 PM CDT, 52 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
1104 PM CDT TUE MAY 16 2017

OKZ037-038-170430-
Tillman OK-Comanche OK-
1104 PM CDT TUE MAY 16 2017

...SIGNIFICANT WEATHER ADVISORY FOR northeastern Tillman and western
Comanche Counties Until 1130 PM CDT...

AT 1102 PM CDT, a strong thunderstorm was located 5 miles northeast
of Hollister, moving northeast at 55 MPH.

HAZARDS INCLUDE...
Hail up to one-half inch diameter...
Wind gusts to 50 MPH...

LAT...LON 3428 9881 3441 9896 3485 9852 3466 9828
      3441 9864 3441 9866 3439 9866
TIME...MOT...LOC 0402Z 224DEG 48KT 3441 9882

..speg.

Special weather statement, May 16, 11:22 PM CDT, 34 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
1122 PM CDT TUE MAY 16 2017

TXZ085-088-170445-
Wilbarger TX-Baylor TX-
1122 PM CDT TUE MAY 16 2017

...SIGNIFICANT WEATHER ADVISORY FOR southwestern Wilbarger and
northwestern Baylor Counties Until 1145 PM CDT...

AT 1121 PM CDT, a strong thunderstorm was located 11 miles southeast
of Thalia, moving northeast at 30 MPH.

HAZARDS INCLUDE...
Hail up to the size of nickels...
Wind gusts to 50 MPH...

LAT...LON 3370 9947 3400 9947 3417 9924 3390 9903
TIME...MOT...LOC 0421Z 234DEG 26KT 3383 9946

..speg.

Special weather statement, May 16, 11:34 PM CDT, 22 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
1134 PM CDT TUE MAY 16 2017

OKZ005-006-010-011-170500-
Major OK-Woodward OK-Alfalfa OK-Woods OK-
1134 PM CDT TUE MAY 16 2017

...SIGNIFICANT WEATHER ADVISORY FOR northwestern Major...east central
Woodward...west central Alfalfa and southeastern Woods Counties Until
midnight CDT...

AT 1133 PM CDT, a strong thunderstorm was located 6 miles south of
Waynoka, moving northeast at 35 MPH.

HAZARDS INCLUDE...
Wind gusts over 50 MPH...

Locations impacted include...
Waynoka, Dacoma, Avard, Bouse Junction and Hopeton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the weather situation closely and be alert for threatening
weather conditions.

&&

LAT...LON 3639 9888 3650 9901 3676 9872 3672 9853
      3663 9843
TIME...MOT...LOC 0433Z 235DEG 32KT 3649 9888

MAHALE

Local storm report, May 16, 11:35 PM CDT, 21 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1135 PM CDT TUE MAY 16 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1100 PM     FLASH FLOOD      6 N CHEYENNE            35.70N 99.68W
05/16/2017                   ROGER MILLS        OK   TRAINED SPOTTER

            DEBRIS FILLED FLOOD WATERS RUNNING OVER HIGHWAY 283.

&&

TLINDLEY

The office that day

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

Issued	Product	Office	Counties	Lasted
May 16, 7:08 PM CDT	Tornado Warning Tornado observedConsiderable damage threat	OUN	Beckham, Washita	37 min
May 16, 7:23 PM CDT	Severe Thunderstorm Warning	OUN	Custer, Washita	37 min
May 16, 7:25 PM CDT	Tornado Warning	OUN	Custer, Washita	35 min
May 16, 7:26 PM CDT	Severe Thunderstorm Warning	OUN	Greer, Jackson, Kiowa	49 min
May 16, 7:42 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Dewey, Major, Woods, Woodward	48 min
May 16, 7:55 PM CDT	Tornado Warning	OUN	Custer	35 min
May 16, 7:57 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Custer, Dewey	48 min
May 16, 8:03 PM CDT	Severe Thunderstorm Warning	OUN	Kiowa	42 min
May 16, 8:13 PM CDT	Severe Thunderstorm Warning	OUN	Dewey, Ellis, Roger Mills, Woodward	47 min
May 16, 8:18 PM CDT	Severe Thunderstorm Warning	OUN	Jackson	42 min
May 16, 8:33 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Dewey, Major	42 min
May 16, 8:33 PM CDT	Severe Thunderstorm Warning	OUN	Kiowa, Washita	42 min
May 16, 8:44 PM CDT	Special Weather Statement	OUN	Blaine	31 min
May 16, 8:53 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Dewey, Major, Woodward	52 min
May 16, 9:03 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Kiowa, Washita	42 min
May 16, 9:36 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Canadian	39 min
May 16, 9:39 PM CDT	Severe Thunderstorm Warning	OUN	Major	51 min
May 16, 9:46 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa, Garfield, Grant	44 min
May 16, 9:51 PM CDT	Severe Thunderstorm Warning	OUN	Beckham, Custer, Dewey, Ellis, Roger Mills	39 min
May 16, 9:53 PM CDT	Areal Flood Advisory	OUN	Dewey, Major, Roger Mills	3 hr
May 16, 9:57 PM CDT	Areal Flood Advisory	OUN	Roger Mills	3 hr
May 16, 10:02 PM CDT	Severe Thunderstorm Warning	OUN	Beckham, Roger Mills	28 min
May 16, 10:07 PM CDT	Special Weather Statement	OUN	Kiowa	38 min
May 16, 10:17 PM CDT	Flash Flood Warning	OUN	Roger Mills	3 hr
May 16, 10:22 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa, Garfield, Grant, Major	53 min
May 16, 10:27 PM CDT	Severe Thunderstorm Warning	OUN	Beckham, Custer, Dewey, Ellis, Roger Mills, Woodward	48 min
May 16, 11:04 PM CDT	Special Weather Statement	OUN	Comanche	26 min
May 16, 11:14 PM CDT	Flash Flood Warning	OUN	Dewey, Woodward	2 hr
May 16, 11:16 PM CDT	Severe Thunderstorm Warning	OUN	Comanche, Cotton, Tillman	44 min
May 16, 11:19 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa, Major, Woods	41 min
May 16, 11:26 PM CDT	Areal Flood Advisory	OUN	Custer, Roger Mills	3 hr
May 16, 11:34 PM CDT	Special Weather Statement	OUN	Woods	26 min
May 16, 11:56 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Comanche, Grady, Stephens	49 min
May 17, 12:03 AM CDT	Special Weather Statement	OUN	Cotton, Tillman	27 min
May 17, 12:17 AM CDT	Wind Advisory	OUN	Blaine, Caddo, Canadian, Cleveland, Comanche, Custer and 11 more	103 min
May 17, 12:32 AM CDT	Severe Thunderstorm Warning	OUN	Cleveland, Grady, McClain	43 min
May 17, 12:46 AM CDT	Severe Thunderstorm Warning	OUN	Caddo, Comanche, Cotton, Grady, Jefferson, Stephens	29 min
May 17, 1:02 AM CDT	Severe Thunderstorm Warning	OUN	Oklahoma	28 min
May 17, 1:12 AM CDT	Severe Thunderstorm Warning	OUN	Logan, Oklahoma	33 min
May 17, 1:14 AM CDT	Severe Thunderstorm Warning	OUN	Cleveland, Lincoln, Pottawatomie	46 min
May 17, 1:14 AM CDT	Severe Thunderstorm Warning	OUN	Carter, Comanche, Garvin, Grady, Jefferson, McClain and 2 more	31 min
May 17, 1:31 AM CDT	Special Weather Statement	OUN	Payne	29 min
May 17, 1:43 AM CDT	Severe Thunderstorm Warning	OUN	Carter, Cleveland, Garvin, McClain, Murray, Pontotoc and 2 more	47 min
May 17, 2:54 AM CDT	Special Weather Statement	OUN	Love	36 min
May 17, 6:28 AM CDT	River Flood Warning	OUN	Dewey, Major, Woodward	25 hr
May 17, 10:04 AM CDT	Wind Advisory	OUN	Alfalfa, Blaine, Canadian, Custer, Dewey, Ellis and 14 more	6 hr

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2017 Every 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.