Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 798, NWS Norman, OK

August 15, 2017Hughes County, Seminole County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Aug 15, 2017, 5:35 PM CDT for Hughes County, Seminole County, Oklahoma. It was in force for 40 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
Aug 15, 2017, 5:35 PM CDT (22:35 UTC)
Expired
Aug 15, 2017, 6:15 PM CDT
In force
40 min
Issued by
NWS Norman, OK
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Hughes County, OK, Seminole County, OK

The radar

The Norman radar (KTLX), 81 km from the middle of the area, began a volume at 22:38 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

Norman, OK (KOUN), launched 12:00Z, 10.6 hours before the alert went out and 89 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 2017-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1305 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 12:00Z on 2017-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 144 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
1305 J/kg
Mixed-layer CIN
-77 J/kg
Mixed-layer LCL
1087 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
144 m²/s²
0-3 km storm-relative helicity
151 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.7

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.

NWS Norman, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 15, 3:25 PM CDT, 2 hours 10 minutes earlier.

Area forecast discussion, Aug 15, 3:25 PM CDT, 2 hours 10 minutes before
Area Forecast Discussion
National Weather Service Norman OK
325 PM CDT Tue Aug 15 2017

.DISCUSSION...
Warm and very humid conditions over Oklahoma and western north
Texas will help fuel strong storms this afternoon and evening.
Very heavy rain is expected with the stronger storms, which may
lead to areas of flooding if storms train or slow down
sufficiently. There is not enough confidence in flooding to
warrant a Flood Watch in this case. Persistent cloud cover has
maintained a relatively stable area over southwest Oklahoma and
much of north Texas, so this area will see mainly showers, with
only a few weak thunderstorms. The stronger storms should be
limited to central and north-central Oklahoma this
afternoon/evening.

Over the next several days, a series of mid/upper-level waves will
pass over the region, causing periodic increases/decreases in rain
chances. One of the stronger waves passes overhead tomorrow and
tomorrow night, bringing the highest rain chances to the area,
along with a risk of additional severe storms. This will be
followed by a brief break (lower rain chances) before additional
waves arrive. The more subtle waves are very difficult for models
(and us) to forecast beyond a day or two, so the rain forecast is
fairly "broadbrushed" until the final significant wave moves
through Friday night.

Both of the stronger waves will be associated with surface
fronts, but no major changes in temperatures are expected.

CmS
&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  74  91  71  90 /  60  40  70  10
Hobart OK         73  94  71  92 /  40  20  60  20
Wichita Falls TX  77  95  73  93 /  50  30  50  30
Gage OK           71  89  65  89 /  30  20  10  10
Ponca City OK     74  90  69  89 /  60  60  60  10
Durant OK         77  92  75  90 /  20  30  50  30

&&

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

03/23
Hazardous weather outlook, Aug 15, 11:02 AM CDT, 6 hours 33 minutes before
Hazardous Weather Outlook...UPDATED
National Weather Service Norman OK
1102 AM CDT Tue Aug 15 2017

OKZ004>048-050>052-TXZ083>090-161615-
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-
1102 AM CDT Tue Aug 15 2017

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

.DAY ONE...Today and Tonight...

.Thunderstorms...
Scattered thunderstorms will be possible over central and northern
OK this afternoon and evening. A few of these storms may become
strong to severe with a threat of damaging wind gusts and hail.
Very heavy rainfall may also result in localized flooding.

Thunderstorm chances will increase across southern Oklahoma and
western north Texas through tonight. Localized heavy rainfall will
be the main threat with these storms.

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

.Thunderstorms...
Thunderstorms will be possible each day through Sunday. A few
strong to severe storms will be possible across northern into
central sections of Oklahoma Wednesday evening.

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, Aug 15, 4:27 PM CDT, 1 hour 8 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
427 PM CDT TUE AUG 15 2017

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

0335 PM     TSTM WND GST     1 SE STILLWATER         36.10N 97.04W
08/15/2017  E60 MPH          PAYNE              OK   PUBLIC

            50-60 MPH. TIME ESTIMATED BY RADAR. NO
            DAMAGE REPORTED.

&&

MAD
Special weather statement, Aug 15, 4:30 PM CDT, 1 hour 5 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
430 PM CDT TUE AUG 15 2017

OKZ030-031-152200-
Pottawatomie OK-Seminole OK-
430 PM CDT TUE AUG 15 2017

...SIGNIFICANT WEATHER ADVISORY FOR northeastern Pottawatomie and
northeastern Seminole Counties Until 500 PM CDT...

AT 429 PM CDT, a strong thunderstorm was located near Little, moving
northeast at 20 MPH.

HAZARDS INCLUDE...
Hail up to one-half inch diameter...
Wind gusts to 50 MPH...
Minor flooding in areas of poor drainage...

Locations impacted include...
Seminole, Cromwell, Little and Centerview.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3523 9664 3538 9672 3546 9664 3546 9663
      3540 9662 3539 9661 3541 9659 3539 9655
      3539 9653 3544 9657 3545 9655 3546 9654
      3543 9651 3543 9649 3546 9648 3546 9645
      3531 9644
TIME...MOT...LOC 2129Z 226DEG 18KT 3533 9664

BRB
Special weather statement, Aug 15, 4:54 PM CDT, 41 minutes before
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Special weather statement, Aug 15, 5:01 PM CDT, 34 minutes before
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Special weather statement, Aug 15, 5:24 PM CDT, 11 minutes before
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Special weather statement, Aug 15, 5:28 PM CDT, 7 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Aug 15, 4:18 AM CDTAreal Flood AdvisoryOUNJackson117 min
Aug 15, 7:19 AM CDTRiver Flood WarningOUNCotton24 hr
Aug 15, 10:25 AM CDTSpecial Weather StatementOUNOklahoma50 min
Aug 15, 2:13 PM CDTSpecial Weather StatementOUNGrady47 min
Aug 15, 2:38 PM CDTSpecial Weather StatementOUNLogan37 min
Aug 15, 3:11 PM CDTSpecial Weather StatementOUNPayne34 min
Aug 15, 3:13 PM CDTSpecial Weather StatementOUNOklahoma32 min
Aug 15, 3:21 PM CDTSpecial Weather StatementOUNLincoln24 min
Aug 15, 3:35 PM CDTSpecial Weather StatementOUNOklahoma25 min
Aug 15, 3:43 PM CDTSpecial Weather StatementOUNLincoln, Payne32 min
Aug 15, 4:05 PM CDTSpecial Weather StatementOUNCanadian25 min
Aug 15, 4:10 PM CDTAreal Flood AdvisoryOUNCanadian, Oklahoma2 hr
Aug 15, 4:13 PM CDTSpecial Weather StatementOUNPayne32 min
Aug 15, 4:17 PM CDTSpecial Weather StatementOUNLincoln28 min
Aug 15, 4:24 PM CDTSpecial Weather StatementOUNOklahoma36 min
Aug 15, 4:30 PM CDTSpecial Weather StatementOUNSeminole30 min
Aug 15, 4:42 PM CDTFlash Flood WarningOUNOklahoma2 hr
Aug 15, 4:54 PM CDTSpecial Weather StatementOUNOklahoma36 min
Aug 15, 5:01 PM CDTSpecial Weather StatementOUNLincoln29 min
Aug 15, 5:12 PM CDTAreal Flood AdvisoryOUNLincoln2 hr
Aug 15, 5:24 PM CDTSpecial Weather StatementOUNSeminole36 min
Aug 15, 5:28 PM CDTSpecial Weather StatementOUNOklahoma32 min
Aug 15, 5:59 PM CDTSpecial Weather StatementOUNOklahoma31 min
Aug 15, 6:14 PM CDTSpecial Weather StatementOUNSeminole46 min
Aug 15, 6:27 PM CDTSpecial Weather StatementOUNPontotoc33 min

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.