Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 42, NWS Norman, OK

April 13, 2018Bryan County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Apr 13, 2018, 4:22 PM CDT for Bryan County, Oklahoma. It was in force for 53 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Apr 13, 2018, 4:22 PM CDT (21:22 UTC)
Expired: Apr 13, 2018, 5:15 PM CDT
In force: 53 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

County Bryan County, OK

The radar

The Norman radar (KTLX), 179 km from the middle of the area, began a volume at 21:22 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 watch it was issued in

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

Issued	Product	Office	Lasted
Apr 13, 1:20 PM CDT	Tornado Watch	SPC	9 hr

The nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 9.4 hours before the alert went out and 158 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: 731 J/kg
Mixed-layer CIN: -418 J/kg
Mixed-layer LCL: 788 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 189 m²/s²
0-3 km storm-relative helicity: 250 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

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 Apr 13, 4:16 PM CDT, 6 minutes earlier.

Area forecast discussion, Apr 13, 4:16 PM CDT, 6 minutes before

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Hazardous weather outlook, Apr 13, 11:38 AM CDT, 4 hours 44 minutes before

Hazardous Weather Outlook
National Weather Service Norman OK
1138 AM CDT Fri Apr 13 2018

OKZ004>048-050>052-TXZ083>090-141015-
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-
1138 AM CDT Fri Apr 13 2018

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

.DAY ONE...This Afternoon and Tonight...

.Fire Weather...
Extreme fire weather conditions will continue for western and
central Oklahoma and western north Texas through mid-evening.

.Thunderstorms...
Thunderstorms will be possible near and east of a dryline as it
moves east. Some of the storms could become severe this afternoon.
Severe storms will be possible along and east of a line from
Stillwater, to Pauls Valley, to Ardmore. Hail up to the size of
golf balls is likely with the stronger storms, especially east of
a line from Seminole and Ada, to Madill.

.Strong Wind...
Strong gusty winds are expected this afternoon and again overnight
through Saturday. Wind gusts of 40 to 55 mph will be possible at
times, especially over the western half of Oklahoma and adjacent
parts of northern Texas. The strong winds could cause blowing
dust leading to reduced visibility.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday...

.Fire Weather...
Critical fire weather conditions will be possible across western
Oklahoma and adjacent portions of Texas on Saturday due to strong
northerly winds. Critical fire weather conditions are expected
again next Tuesday as temperatures warm back up and winds become
gusty.

.Strong Wind...
Strong gusty winds are expected Saturday. Wind gusts of 40 to 50
mph will be possible, especially across the western half of
Oklahoma and adjacent north Texas.

.Frost/Freeze...
Subfreezing temperatures are likely across much of Oklahoma
Sunday morning. Some frost and subfreezing temperatures will also
be possible across portions of Oklahoma Monday morning, especially
across the northeastern half of the state.

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, Apr 13, 2:51 PM CDT, 1 hour 31 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
251 PM CDT FRI APR 13 2018

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

0246 PM     HAIL             MILL CREEK              34.41N 96.83W
04/13/2018  E1.00 INCH       JOHNSTON           OK   COUNTY OFFICIAL

&&

JP

Local storm report, Apr 13, 3:42 PM CDT, 40 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
342 PM CDT FRI APR 13 2018

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

0337 PM     HAIL             1 ENE KINGSTON          34.01N 96.70W
04/13/2018  E0.75 INCH       MARSHALL           OK   TRAINED SPOTTER

&&

JP

Local storm report, Apr 13, 3:48 PM CDT, 34 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
348 PM CDT FRI APR 13 2018

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

0336 PM     HAIL             6 SE GERTY              34.76N 96.22W
04/13/2018  E1.00 INCH       COAL               OK   PUBLIC

&&

JP

Special weather statement, Apr 13, 4:09 PM CDT, 13 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
409 PM CDT FRI APR 13 2018

OKZ043-048-132145-
Coal OK-Atoka OK-
409 PM CDT FRI APR 13 2018

...SIGNIFICANT WEATHER ADVISORY FOR eastern Coal and north central
Atoka Counties Until 445 PM CDT...

AT 408 PM CDT, a strong thunderstorm was located over Coalgate,
moving northeast at 35 MPH.

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

Locations impacted include...
Coalgate, Stringtown, Lehigh, Wardville, Phillips, Atoka Reservoir
and Chockie.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3442 9614 3442 9639 3477 9610 3477 9609
      3468 9609 3468 9588 3460 9588
TIME...MOT...LOC 2108Z 229DEG 32KT 3454 9623

03

Special weather statement, Apr 13, 4:18 PM CDT, 4 minutes before

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Local storm report, Apr 13, 4:20 PM CDT, 2 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 12, 7:50 PM CDT	Special Weather Statement	OUN	Dewey	55 min
Apr 12, 7:55 PM CDT	Special Weather Statement	OUN	Woodward	65 min
Apr 13, 3:31 AM CDT	Wind Advisory	OUN	Alfalfa, Beckham, Blaine, Caddo, Canadian, Carter and 31 more	40 hr
Apr 13, 4:56 AM CDT	Special Weather Statement	OUN	McClain	34 min
Apr 13, 8:30 AM CDT	Special Weather Statement	OUN	Dewey	30 min
Apr 13, 9:04 AM CDT	Special Weather Statement	OUN	Woodward	26 min
Apr 13, 12:57 PM CDT	Special Weather Statement	OUN	Kay	33 min
Apr 13, 12:59 PM CDT	Special Weather Statement	OUN	Oklahoma	31 min
Apr 13, 1:05 PM CDT	Special Weather Statement	OUN	Carter	25 min
Apr 13, 1:08 PM CDT	Special Weather Statement	OUN	Oklahoma	37 min
Apr 13, 1:22 PM CDT	Special Weather Statement	OUN	Cleveland, Garvin	23 min
Apr 13, 1:34 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Love, Murray	41 min
Apr 13, 1:37 PM CDT	Severe Thunderstorm Warning	OUN	Cleveland, McClain, Pottawatomie, Seminole	53 min
Apr 13, 1:39 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln, Payne	51 min
Apr 13, 2:02 PM CDT	Special Weather Statement	OUN	Lincoln	28 min
Apr 13, 2:05 PM CDT	Special Weather Statement	OUN	Garvin	25 min
Apr 13, 2:10 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, McClain, Murray, Pontotoc	28 min
Apr 13, 2:13 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Johnston, Murray, Pontotoc	47 min
Apr 13, 2:19 PM CDT	Severe Thunderstorm Warning	OUN	Hughes, Pottawatomie, Seminole	56 min
Apr 13, 2:26 PM CDT	Tornado Warning	OUN	Seminole	27 min
Apr 13, 2:38 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Johnston, Love, Marshall	52 min
Apr 13, 2:45 PM CDT	Fire Weather Watch	OUN	Beckham, Custer, Dewey, Ellis, Greer, Harmon and 7 more	13 hr
Apr 13, 2:48 PM CDT	Severe Thunderstorm Warning	OUN	Coal, Johnston, Pontotoc	42 min
Apr 13, 3:19 PM CDT	Freeze Watch	OUN	Alfalfa, Atoka, Beckham, Blaine, Bryan, Caddo and 42 more	30 hr
Apr 13, 3:19 PM CDT	Freeze Warning	OUN	Ellis, Harper, Woods, Woodward	18 hr
Apr 13, 3:21 PM CDT	Severe Thunderstorm Warning	OUN	Atoka, Coal, Hughes	39 min
Apr 13, 3:27 PM CDT	Severe Thunderstorm Warning	OUN	Atoka, Bryan, Johnston, Marshall	48 min
Apr 13, 4:09 PM CDT	Special Weather Statement	OUN	Coal	36 min
Apr 13, 4:11 PM CDT	Severe Thunderstorm Warning	OUN	Atoka	49 min
Apr 13, 4:18 PM CDT	Special Weather Statement	OUN	Bryan	27 min
Apr 13, 4:52 PM CDT	Special Weather Statement	OUN	Bryan	23 min
Apr 13, 4:58 PM CDT	Severe Thunderstorm Warning	OUN	Atoka	17 min
Apr 13, 5:13 PM CDT	Special Weather Statement	OUN	Bryan	62 min
Apr 13, 5:30 PM CDT	Severe Thunderstorm Warning	OUN	Atoka	15 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2018 Every severe thunderstorm warning in 2018

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.