Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 603, NWS Norman, OK

November 30, 20184 counties in Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Nov 30, 2018, 7:45 PM CST for 4 counties in Oklahoma. It was in force for 45 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: Nov 30, 2018, 7:45 PM CST (01:45 UTC)
Expired: Nov 30, 2018, 8:30 PM CST
In force: 45 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Comanche County, OK, Cotton County, OK, Grady County, OK, Stephens County, OK

The radar

The Altus AFB radar (KFDR), 81 km from the middle of the area, began a volume at 01:48 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
Nov 30, 5:23 PM CST	Tornado Watch	SPC	8 hr

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 1.8 hours before the alert went out and 96 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: 946 J/kg
Mixed-layer CIN: -21 J/kg
Mixed-layer LCL: 798 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 230 m²/s²
0-3 km storm-relative helicity: 244 m²/s²
Significant tornado parameter: 1.1
Supercell composite: 5.7

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.

Hazardous weather outlook, Nov 30, 6:13 PM CST, 1 hour 32 minutes before

Hazardous Weather Outlook...UPDATED
National Weather Service Norman OK
613 PM CST Fri Nov 30 2018

OKZ004>048-050>052-TXZ083>090-020015-
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-
613 PM CST Fri Nov 30 2018

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

.DAY ONE...Through Tonight...

.Thunderstorms...
There is a Slight Risk of severe thunderstorms this evening
across portions of Oklahoma and north Texas.

Location...
The Slight Risk area extends east of a line from Freedom to
Clinton to Cache and Randlett Oklahoma to Henrietta Texas. A
Marginal Risk covers the area between the Slight Risk area and a
line from Laverne to Erick Oklahoma to Electra, Texas.

Timing...
The main risk will be through midnight.

Impacts...
Hail up to the size of baseballs, wind gusts 60 to 80 mph, and
tornadoes will be possible.

Discussion...
Scattered thunderstorms will continue to move across much of the
eastern two-thirds of Oklahoma and portions of western north Texas
this evening. Instability will be marginal for severe storms, but
wind fields will be very supportive. This will result in low-
topped supercell storms during the evening hours. The storms will
move quickly to the east or northeast.

.SPOTTER AND EMERGENCY MANAGEMENT STATEMENT...

Storm spotter groups and emergency management personnel across
these risk areas should prepare for severe weather operations
through the evening hours.

.Fog...
Areas of dense fog will continue this evening across northwestern
Oklahoma.

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

.Fire weather...
Warm, dry, breezy conditions will result in an elevated risk of
wildfires Saturday afternoon across western Oklahoma and adjacent
parts of Texas.

.Winter weather...
Light snow will be possible late Sunday night into early Monday
morning...and again Thursday night, mainly across central and
northern Oklahoma.

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

In the hours before

Special weather statement, Nov 30, 7:19 PM CST, 26 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
719 PM CST FRI NOV 30 2018

OKZ045-010145-
Jefferson OK-
719 PM CST FRI NOV 30 2018

...SIGNIFICANT WEATHER ADVISORY FOR southeastern Jefferson County
Until 745 PM CST....

AT 717 PM CST, a strong thunderstorm was located near Terral, moving
northeast at 55 MPH.

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

LAT...LON 3388 9797 3390 9798 3393 9795 3394 9797
      3399 9795 3401 9797 3399 9802 3429 9758
      3429 9756 3400 9755 3397 9762 3399 9768
      3394 9773 3394 9776 3392 9778 3389 9778
      3390 9780 3388 9780 3385 9788
TIME...MOT...LOC 0117Z 236DEG 46KT 3395 9793

..speg.

Special weather statement, Nov 30, 7:20 PM CST, 25 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
720 PM CST FRI NOV 30 2018

OKZ028>030-010145-
Pottawatomie OK-Cleveland OK-McClain OK-
720 PM CST FRI NOV 30 2018

...SIGNIFICANT WEATHER ADVISORY FOR southwestern Pottawatomie...
Cleveland and southwestern McClain Counties Until 745 PM CST....

AT 717 PM CST, strong thunderstorms were along a line extending from
near Goldsby to near Purcell, moving east at 35 MPH.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3491 9747 3519 9759 3538 9729 3538 9714
      3503 9693
TIME...MOT...LOC 0117Z 250DEG 29KT 3516 9748 3506 9738

BRB

Special weather statement, Nov 30, 7:22 PM CST, 23 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
722 PM CST FRI NOV 30 2018

OKZ028-039>041-046-010145-
Stephens OK-Carter OK-Garvin OK-McClain OK-Murray OK-
722 PM CST FRI NOV 30 2018

...SIGNIFICANT WEATHER ADVISORY FOR eastern Stephens...northwestern
Carter...Garvin...southeastern McClain and western Murray Counties
Until 745 PM CST....

AT 720 PM CST, strong thunderstorms were along a line extending from
near Paoli to near Velma, moving northeast at 25 MPH.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3429 9781 3484 9751 3493 9714 3491 9702
      3494 9693 3487 9695 3429 9730
TIME...MOT...LOC 0120Z 234DEG 21KT 3484 9724 3446 9765

BRB

Special weather statement, Nov 30, 7:23 PM CST, 22 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
723 PM CST FRI NOV 30 2018

OKZ019-025-010200-
Oklahoma OK-Logan OK-
723 PM CST FRI NOV 30 2018

...SIGNIFICANT WEATHER ADVISORY FOR central Oklahoma and south
central Logan Counties Until 800 PM CST....

AT 722 PM CST, a strong thunderstorm was located over northwestern
Oklahoma City, moving northeast at 45 MPH.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3565 9714 3554 9714 3540 9753 3555 9766
      3582 9729
TIME...MOT...LOC 0122Z 234DEG 41KT 3553 9752

BRB

Local storm report, Nov 30, 7:34 PM CST, 11 minutes before

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Special weather statement, Nov 30, 7:45 PM CST, 0 minutes before

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</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
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      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Nov 30, 6:00 PM CST	Special Weather Statement	OUN	Stephens	30 min
Nov 30, 6:22 PM CST	Special Weather Statement	OUN	Jefferson	23 min
Nov 30, 6:26 PM CST	Special Weather Statement	OUN	Grady	34 min
Nov 30, 6:34 PM CST	Special Weather Statement	OUN	Tillman	26 min
Nov 30, 6:45 PM CST	Special Weather Statement	OUN	McClain	30 min
Nov 30, 6:48 PM CST	Severe Thunderstorm Warning	OUN	Canadian, Cleveland, Grady, McClain, Oklahoma	42 min
Nov 30, 7:04 PM CST	Severe Thunderstorm Warning	OUN	Comanche, Cotton, Tillman	41 min
Nov 30, 7:19 PM CST	Special Weather Statement	OUN	Jefferson	26 min
Nov 30, 7:20 PM CST	Special Weather Statement	OUN	Cleveland, McClain	25 min
Nov 30, 7:22 PM CST	Special Weather Statement	OUN	Garvin	23 min
Nov 30, 7:23 PM CST	Special Weather Statement	OUN	Oklahoma	37 min
Nov 30, 7:38 PM CST	Severe Thunderstorm Warning	OUN	Caddo, Comanche	32 min
Nov 30, 7:45 PM CST	Special Weather Statement	OUN	Garvin	30 min
Nov 30, 7:49 PM CST	Special Weather Statement	OUN	Pottawatomie	26 min
Nov 30, 8:08 PM CST	Special Weather Statement	OUN	Payne	37 min
Nov 30, 8:13 PM CST	Special Weather Statement	OUN	Lincoln, Pottawatomie	32 min
Nov 30, 8:16 PM CST	Special Weather Statement	OUN	Carter, Murray	29 min
Nov 30, 8:26 PM CST	Special Weather Statement	OUN	Marshall	34 min
Nov 30, 8:33 PM CST	Severe Thunderstorm Warning	OUN	Lincoln	13 min
Nov 30, 8:35 PM CST	Severe Thunderstorm Warning	OUN	Carter, Johnston, Murray, Pontotoc	25 min
Nov 30, 8:41 PM CST	Special Weather Statement	OUN	Cleveland, McClain, Oklahoma	34 min
Nov 30, 9:03 PM CST	Special Weather Statement	OUN	Coal	27 min
Nov 30, 9:14 PM CST	Severe Thunderstorm Warning	OUN	Atoka, Bryan, Coal, Johnston	46 min
Nov 30, 9:15 PM CST	Special Weather Statement	OUN	Lincoln, Logan, Payne	30 min
Nov 30, 9:17 PM CST	Special Weather Statement	OUN	Seminole	28 min
Nov 30, 6:36 PM CST	Special Weather Statement	OUN	Clay	24 min
Nov 30, 6:55 PM CST	Special Weather Statement	OUN	Wichita	35 min
Nov 30, 7:01 PM CST	Special Weather Statement	OUN	Clay	29 min
Nov 30, 7:08 PM CST	Severe Thunderstorm Warning	OUN	Clay	22 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.