Alert archive / Oklahoma / Special Weather Statements in 2021

Special Weather Statement, NWS Norman, OK

May 27, 2021Stephens County, Oklahoma

NWS Norman, OK issued this special weather statement at May 27, 2021, 8:09 PM CDT for Stephens County, Oklahoma. It was in force for 36 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 27, 2021, 8:09 PM CDT (01:09 UTC)
Expired: May 27, 2021, 8:45 PM CDT
In force: 36 min
Issued by: NWS Norman, OK

County Stephens County, OK

The radar

The Norman radar (KTLX), 91 km from the middle of the area, began a volume at 01:10 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

Fort Worth, TX (KFWD), launched 00:00Z, 1.2 hours before the alert went out and 217 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: 1480 J/kg
Mixed-layer CIN: -150 J/kg
Mixed-layer LCL: 1331 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 124 m²/s²
0-3 km storm-relative helicity: 203 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 3.7

Open this sounding in Storm Lab

The text

As transmitted.

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

What forecasters said that day

The local office's own words before this special weather statement 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 special weather statement went out at May 27, 6:14 PM CDT, 1 hour 55 minutes earlier.

Area forecast discussion, May 27, 6:14 PM CDT, 1 hour 55 minutes before

Area Forecast Discussion
National Weather Service Norman OK
614 PM CDT Thu May 27 2021

...New AVIATION...

.SHORT TERM...
(This evening through Friday)
Issued at 224 PM CDT Thu May 27 2021

Strong to severe thunderstorms will continue into the evening
across most of the area as a cold front moves into minimally-
capped environment (per 18Z special upper air sounding). The
ongoing storms could push out an outflow boundary or two, which
could lead to slight enhancement of a tornado threat if any storms
can form along it, as winds ahead of the boundary could be backed
slightly. Currently, as storms form along the aforementioned cold
front later this afternoon, there may be a brief window for some
discrete storms. The deep-layer shear vector being mostly
parallel to the boundary will foster storm conglomeration shortly
after initiation, and eventually forming into a line that will
move through west-central and central OK. The main threats still
appear to be damaging winds in excess of 80mph and hail up to the
size of baseballs, as SPC mesoanalysis suggests there is at least
MLCAPE values upwards of at least 3000 J/kg across the area. With
numerous storms producing heavy rain rates across areas with
already moist soils, flooding and flash flooding could be possible
across central OK into northern and northeast OK.

Bunker

&&

.LONG TERM...
(Friday night through next Wednesday)
Issued at 224 PM CDT Thu May 27 2021

Over the weekend mid-level heights will gradually increase as an
approaching mid-level ridge moves into the area. Showers and
thunderstorms are possible on Sunday as a shortwave trough
traverses the area and attendant upslope flow along the Rockies.
Another shortwave should move through on Monday morning, bringing
with it additional chances for showers and storms. A longwave
trough will move in by Tuesday morning and an associated cold
front will bring in showers and storms across the area. Northerly
surface flow should persist through much of the long term, with
slight chances for showers and storms. High temperatures should
stay in the mid to upper 70s across most of the area throughout
the period.

Bunker

&&

.AVIATION...
(00Z TAFS)
Issued at 609 PM CDT Thu May 27 2021

Showers and thunderstorms will continue to move south across the
area this evening. Some MVFR ceilings and visibilities are
possible with these storms as they move through. Otherwise,
northerly winds will persist through the period behind the cold
front. Ceilings should generally lift after the storms pass.

&&

.UPPER AIR...
Issued at 224 PM CDT Thu May 27 2021

An Upper Air flight is planned later at 00Z..

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  59  72  54  72 /  90   0  10  10
Hobart OK         60  75  56  74 /  70  10  10  10
Wichita Falls TX  65  77  60  76 /  80  30  30  20
Gage OK           53  72  53  73 /  10  10  10  10
Ponca City OK     53  72  50  72 /  50   0   0   0
Durant OK         66  80  59  75 /  90  30  20  10

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Flood Watch until 1 AM CDT Friday for OKZ008-012-013-018>020-
     024>031.

TX...None.
&&

SHORT TERM...13
LONG TERM....13
AVIATION...13

Hazardous weather outlook, May 27, 6:51 PM CDT, 1 hour 18 minutes before

Hazardous Weather Outlook
National Weather Service Norman OK
651 PM CDT Thu May 27 2021

OKZ004>048-050>052-TXZ083>090-290000-
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-
651 PM CDT Thu May 27 2021

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

.DAY ONE...Tonight...

.Thunderstorms...
There is an enhanced risk for severe thunderstorms Thursday
evening across most of central and southern Oklahoma into parts
of western north Texas. Storms will continue to develop along a
cold front in central OK and move south across the area. Large
hail up to the size of baseballs and damaging winds up to 80 mph
will be the main threats. During the early evening there will
also be a low tornado risk.

.Heavy Rainfall...
Localized heavy rainfall and flooding will be possible late on
Thursday, mainly across central and southern Oklahoma and north
Texas.

.SPOTTER AND EMERGENCY MANAGEMENT STATEMENT...

Storm spotter groups and emergency management personnel across
Oklahoma and western north Texas should prepare for severe
weather operations this evening.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday...

.Thunderstorms...
Friday and Saturday will see thunderstorm chances across mainly
southern Oklahoma and north Texas. More widespread chances for
showers and storms will return Sunday through Wednesday of next
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 27, 7:27 PM CDT, 42 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
727 PM CDT THU MAY 27 2021

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

0719 PM     FLASH FLOOD      2 NW NORMAN             35.24N 97.46W
05/27/2021                   CLEVELAND          OK   EMERGENCY MNGR

            GODDARD STREET FLOODED AT FIRE STATION 7.

&&

Local storm report, May 27, 7:29 PM CDT, 40 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
729 PM CDT THU MAY 27 2021

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

0726 PM     FLASH FLOOD      1 SSW NORMAN            35.20N 97.45W
05/27/2021                   CLEVELAND          OK   TRAINED SPOTTER

            AT LEAST 3 CARS STALLED AT LINDSEY/ELM
            STREET INTERSECTION. WATER UP TO 2 FEET.

&&

Special weather statement, May 27, 7:35 PM CDT, 34 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
735 PM CDT Thu May 27 2021

OKZ027-280100-
Grady OK-
735 PM CDT Thu May 27 2021

...SIGNIFICANT WEATHER ADVISORY FOR central Grady County Until 800 PM
CDT...

AT 732 PM CDT, a strong thunderstorm was located near Norge, moving
southeast at 25 MPH.

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

LAT...LON 3495 9809 3502 9809 3514 9802 3503 9767
      3493 9767 3477 9777
TIME...MOT...LOC 0032Z 298DEG 21KT 3503 9800

..speg.

Local storm report, May 27, 7:46 PM CDT, 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
746 PM CDT THU MAY 27 2021

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

0741 PM     FLASH FLOOD      NORMAN                  35.22N 97.44W
05/27/2021                   CLEVELAND          OK   LAW ENFORCEMENT

            MAIN AND PETERS FLOODED WITH MANHOLE COVERS
            DISLODGED.

&&

Local storm report, May 27, 7:55 PM CDT, 14 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
755 PM CDT THU MAY 27 2021

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

0752 PM     FLOOD            1 W SHAWNEE             35.33N 96.94W
05/27/2021                   POTTAWATOMIE       OK   EMERGENCY MNGR

            BENEDICT ST IS FLOODED, 1 VEHICLE STALLED,
            TO BE CLOSED.

&&

Special weather statement, May 27, 8:09 PM CDT, 0 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
809 PM CDT Thu May 27 2021

OKZ027-038-039-280145-
Grady OK-Stephens OK-Comanche OK-
809 PM CDT Thu May 27 2021

...SIGNIFICANT WEATHER ADVISORY FOR southern Grady...north central
Stephens and east central Comanche Counties Until 845 PM CDT...

AT 808 PM CDT, a strong thunderstorm was located 4 miles west of Rush
Springs, moving southeast at 25 MPH.

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

LAT...LON 3474 9817 3488 9804 3473 9767 3470 9767
      3449 9784
TIME...MOT...LOC 0108Z 304DEG 23KT 3477 9804

..speg.

The office that day

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

Issued	Product	Office	Counties	Lasted
May 27, 7:06 PM CDT	Areal Flood Advisory	OUN	Lincoln	114 min
May 27, 7:11 PM CDT	Areal Flood Advisory	OUN	Lincoln, Pottawatomie, Seminole	2 hr
May 27, 7:35 PM CDT	Special Weather Statement	OUN	Grady	25 min
May 27, 7:51 PM CDT	Severe Thunderstorm Warning	OUN	Jackson	39 min
May 27, 8:26 PM CDT	Areal Flood Advisory	OUN	Canadian, Cleveland, Kingfisher, Lincoln, Logan, Oklahoma	3 hr
May 27, 8:35 PM CDT	River Flood Watch	OUN	Bryan	14 hr
May 27, 8:41 PM CDT	River Flood Advisory	OUN	Payne	24 hr
May 27, 8:42 PM CDT	River Flood Advisory	OUN	Kingfisher, Logan	24 hr
May 27, 8:57 PM CDT	Special Weather Statement	OUN	Stephens	33 min
May 27, 9:25 PM CDT	Special Weather Statement	OUN	Stephens	35 min
May 27, 9:46 PM CDT	Special Weather Statement	OUN	Tillman	29 min
May 27, 10:04 PM CDT	Severe Thunderstorm Warning	OUN	Cotton, Tillman	41 min
May 27, 10:34 PM CDT	Severe Thunderstorm Warning	OUN	Cotton, Jefferson	41 min
May 27, 11:11 PM CDT	Severe Thunderstorm Warning	OUN	Jefferson, Love	49 min
May 28, 4:42 AM CDT	River Flood Advisory	OUN	Pottawatomie, Seminole	11 hr
May 28, 4:42 AM CDT	River Flood Advisory	OUN	Lincoln, Oklahoma, Pottawatomie	11 hr
May 27, 8:26 PM CDT	Severe Thunderstorm Warning	OUN	Hardeman, Wilbarger	49 min
May 27, 8:34 PM CDT	Special Weather Statement	OUN	Foard	26 min
May 27, 9:06 PM CDT	Severe Thunderstorm Warning	OUN	Wilbarger	39 min
May 27, 9:15 PM CDT	Special Weather Statement	OUN	Wilbarger	30 min
May 27, 10:12 PM CDT	Special Weather Statement	OUN	Wichita	33 min
May 27, 10:36 PM CDT	Severe Thunderstorm Warning	OUN	Foard	39 min
May 27, 11:00 PM CDT	Severe Thunderstorm Warning	OUN	Foard, Knox	45 min
May 27, 11:03 PM CDT	Special Weather Statement	OUN	Foard	27 min
May 27, 11:27 PM CDT	Severe Thunderstorm Warning	OUN	Baylor, Foard, Knox	48 min
May 28, 12:09 AM CDT	Severe Thunderstorm Warning	OUN	Archer, Baylor	51 min
May 28, 12:13 AM CDT	Special Weather Statement	OUN	Knox	32 min
May 28, 12:46 AM CDT	Severe Thunderstorm Warning	OUN	Archer, Clay	44 min
May 28, 1:29 AM CDT	Special Weather Statement	OUN	Clay	31 min
May 28, 2:13 AM CDT	Special Weather Statement	OUN	Foard	32 min
May 28, 4:55 AM CDT	Special Weather Statement	OUN	Foard, Hardeman	35 min
May 28, 5:24 AM CDT	Special Weather Statement	OUN	Foard, Hardeman	36 min
May 28, 8:14 AM CDT	Special Weather Statement	OUN	Hardeman	31 min
May 28, 8:14 AM CDT	Special Weather Statement	OUN	Wilbarger	31 min

Nearby

Special Weather Statements in Oklahoma, 2021 Every special weather statement in 2021

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.