Alert archive / Oklahoma / Special Weather Statements in 2021

Special Weather Statement, NWS Norman, OK

April 28, 2021Garvin County, Oklahoma

NWS Norman, OK issued this special weather statement at Apr 28, 2021, 3:28 AM CDT for Garvin County, Oklahoma. It was in force for 32 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: Apr 28, 2021, 3:28 AM CDT (08:28 UTC)
Expired: Apr 28, 2021, 4:00 AM CDT
In force: 32 min
Issued by: NWS Norman, OK

County Garvin County, OK

The radar

The Norman radar (KTLX), 98 km from the middle of the area, began a volume at 08:28 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 00:00Z, 8.5 hours before the alert went out and 85 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: 661 J/kg
Mixed-layer CIN: -196 J/kg
Mixed-layer LCL: 1104 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 228 m²/s²
0-3 km storm-relative helicity: 198 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.0

Open this sounding in Storm Lab

The text

As transmitted.

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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 Apr 28, 12:39 AM CDT, 2 hours 49 minutes earlier.

Area forecast discussion, Apr 28, 12:39 AM CDT, 2 hours 49 minutes before

Area Forecast Discussion
National Weather Service Norman OK
1239 AM CDT Wed Apr 28 2021

...New AVIATION...

.SHORT TERM...
(This evening through Wednesday)
Issued at 202 PM CDT Tue Apr 27 2021

Thunderstorm initiation has begun in west Texas and this activity
will spread and expand northeast this afternoon and this evening.
Clearing of the mid and high level clouds will allow
destabilization across the west this afternoon, so instability
will increase this afternoon in these area. It is still a little
more in question about how much destabilization we will get
farther northeast as to whether storms toward central Oklahoma
will be surface-based or more elevated. But with time overnight,
the threat will shift more from severe thunderstorm potential to
heavy rain potential as thunderstorm coverage increases. We issued
a Flood Watch already for this scenario as forecast precipitable
water amounts of 1.75" to 2" are quite extreme for late April.

&&

.LONG TERM...
(Wednesday night through next Monday)
Issued at 244 PM CDT Tue Apr 27 2021

The storm system over the southern Plains will be slow to move
away, so rain/thunderstorm chances will diminish only slowly
Wednesday night into Thursday. Rain will end gradually from
northwest to southeast, while drier air moves into the region from
the northwest.

The upper-level system responsible for the current rain/storms is
forecast to cut off over Texas. The various models have very
different ideas as to how the cutoff low will evolve, as is
commonly the case. This leads to rather low-confidence forecasts
from the weekend into early next week.

The most likely scenario is that the upper low will drift slowly
east, similar to, but a little faster than, the 12Z ECMWF outlook.
This would cause a bit of moisture return over our southeast this
weekend, leading to low chances for showers on Sunday. Beyond
that, there is no clear preference in outcomes, so the forecast is
basically a mix of the possibilities.

&&

.AVIATION...
(06Z TAFS)
Issued at 1234 AM CDT Wed Apr 28 2021

Several rounds of showers and thunderstorms are expected overnight
into early Wednesday morning, and then again Wednesday afternoon
and evening. An area of thunderstorms currently extends from just
SE of OUN and SWO to near SPS. Another round will move in from the
southwest after 09Z or so, tracking near the I-44 corridor. MVFR
to IFR cigs and visbys will be possible for most terminals
throughout the forecast period. Winds will also shift from the
north late in the forecast period.

&&

.UPPER AIR...
Issued at 629 PM CDT Tue Apr 27 2021

No upper air flights are currently planned for tonight.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  56  70  47  73 /  60  20  10  10
Hobart OK         53  71  46  75 /  40  20  10  10
Wichita Falls TX  57  71  50  75 /  50  30  10  10
Gage OK           48  71  42  78 /  40  10   0   0
Ponca City OK     55  72  46  74 /  60  20   0  10
Durant OK         61  72  54  74 /  90  60  20  10

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Flood Watch through Thursday morning for OKZ008-013-019-020-
     023>032-037>048-050>052.

TX...Flood Watch through Thursday morning for TXZ085-086-088>090.

&&

SHORT TERM...26
LONG TERM....23
AVIATION...03

Hazardous weather outlook, Apr 28, 12:03 AM CDT, 3 hours 25 minutes before

Hazardous Weather Outlook
National Weather Service Norman OK
1203 AM CDT Wed Apr 28 2021

OKZ004>048-050>052-TXZ083>090-290515-
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-
1203 AM CDT Wed Apr 28 2021

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

.DAY ONE...Tonight...

.Thunderstorms...
Severe thunderstorms are possible overnight mainly south of
Interstate 40. Hail up to the size of golfballs and wind gusts up
to 60 mph will be the main threats, although brief tornadoes
cannot be ruled out mainly before 3 AM.

.Heavy Rainfall and Flooding...
Heavy rainfall could result in flash flooding across portions of
southern Oklahoma and western north Texas thru early Wednesday
morning.

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

.Thunderstorms...
There is a Slight Risk of severe thunderstorms south of line from
near Woodward, to Enid, and to Stillwater. Thunderstorms are
forecast to exit to the east Wednesday morning with additional
thunderstorms expected to redevelop by the afternoon. While large
hail will be the primary hazard over the larger area, all severe
weather hazards are possible, especially across western north
Texas and southwest Oklahoma. Thunderstorms should exit the area
early Thursday morning.

.Heavy Rainfall and Flooding...
Heavy rainfall and flooding will continue to be a hazard on
Wednesday into early Thursday. During this period, the greatest
risk for flooding will be across southeast and south central
Oklahoma.

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 28, 12:44 AM CDT, 2 hours 44 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1244 AM CDT WED APR 28 2021

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

1235 AM     FLASH FLOOD      PAULS VALLEY            34.74N 97.22W
04/28/2021                   GARVIN             OK   TRAINED SPOTTER

            CARS STRANDED AND ROAD CLOSED IN PAULS VALLEY

&&

11

Local storm report, Apr 28, 1:20 AM CDT, 2 hours 8 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
120 AM CDT WED APR 28 2021

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

0108 AM     FLASH FLOOD      PAULS VALLEY            34.74N 97.22W
04/28/2021                   GARVIN             OK   TRAINED SPOTTER

            DOWNTOWN PAULS VALLEY, VEHICLES STRANDED, BUILDINGS
            TAKING ON WATER

&&

11

Special weather statement, Apr 28, 1:31 AM CDT, 1 hour 57 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
131 AM CDT Wed Apr 28 2021

OKZ026-030-031-280700-
Pottawatomie OK-Seminole OK-Lincoln OK-
131 AM CDT Wed Apr 28 2021

...SIGNIFICANT WEATHER ADVISORY FOR northeastern Pottawatomie...
northwestern Seminole and southeastern Lincoln Counties Until 200 AM
CDT...

AT 129 AM CDT, a strong thunderstorm was located near Tecumseh,
moving northeast at 35 MPH.

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

LAT...LON 3518 9689 3523 9701 3554 9682 3547 9662
      3541 9662
TIME...MOT...LOC 0629Z 212DEG 32KT 3525 9687

Zwink

Special weather statement, Apr 28, 1:43 AM CDT, 1 hour 45 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
143 AM CDT Wed Apr 28 2021

OKZ030-031-280715-
Pottawatomie OK-Seminole OK-
143 AM CDT Wed Apr 28 2021

...SIGNIFICANT WEATHER ADVISORY FOR south central Pottawatomie and
northern Seminole Counties Until 215 AM CDT...

AT 142 AM CDT, a strong thunderstorm was located near Asher, moving
northeast at 35 MPH.

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

LAT...LON 3497 9683 3504 9695 3536 9674 3520 9647
TIME...MOT...LOC 0642Z 216DEG 33KT 3499 9688

Zwink

Local storm report, Apr 28, 2:10 AM CDT, 1 hour 18 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
210 AM CDT WED APR 28 2021

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

1200 AM     TORNADO          4 E PAULS VALLEY        34.74N 97.14W
04/28/2021                   GARVIN             OK   EMERGENCY MNGR

            POWERLINES DOWN, SEVERAL TREES 30 INCHES IN
            DIAMETER DOWN, METAL FRAMED BARN DAMAGED.
            PATH AT LEAST ONE MILE LONG NORTH OF E CRD
            1570. TIME ESTIMATED FROM RADAR.

&&

RB

Special weather statement, Apr 28, 3:28 AM CDT, 0 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
328 AM CDT Wed Apr 28 2021

OKZ040-041-046-280900-
Carter OK-Garvin OK-Murray OK-
328 AM CDT Wed Apr 28 2021

...SIGNIFICANT WEATHER ADVISORY FOR northwestern Carter...south
central Garvin and northwestern Murray Counties Until 400 AM CDT...

AT 327 AM CDT, a strong thunderstorm was located near Graham, moving
northeast at 40 MPH.

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

LAT...LON 3434 9756 3438 9756 3477 9736 3460 9702
      3431 9745
TIME...MOT...LOC 0827Z 212DEG 33KT 3439 9747

Zwink

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 27, 7:15 PM CDT	Severe Thunderstorm Warning	OUN	Tillman	45 min
Apr 27, 7:19 PM CDT	Tornado Warning	OUN	Tillman	41 min
Apr 27, 7:53 PM CDT	Severe Thunderstorm Warning	OUN	Comanche, Cotton, Tillman	52 min
Apr 27, 8:10 PM CDT	Severe Thunderstorm Warning	OUN	Cotton, Tillman	50 min
Apr 27, 8:46 PM CDT	Special Weather Statement	OUN	Comanche	29 min
Apr 27, 9:01 PM CDT	Special Weather Statement	OUN	Cotton	29 min
Apr 27, 9:55 PM CDT	Special Weather Statement	OUN	Stephens	50 min
Apr 27, 10:35 PM CDT	Special Weather Statement	OUN	Pottawatomie	25 min
Apr 27, 10:43 PM CDT	Special Weather Statement	OUN	Tillman	32 min
Apr 27, 10:46 PM CDT	Special Weather Statement	OUN	McClain	44 min
Apr 27, 11:05 PM CDT	Special Weather Statement	OUN	Pottawatomie, Seminole	25 min
Apr 27, 11:24 PM CDT	Special Weather Statement	OUN	Cleveland, Garvin, McClain	36 min
Apr 27, 11:41 PM CDT	Special Weather Statement	OUN	Seminole	34 min
Apr 27, 11:42 PM CDT	Special Weather Statement	OUN	Cotton	33 min
Apr 27, 11:49 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, McClain, Murray	26 min
Apr 27, 11:58 PM CDT	Tornado Warning	OUN	Garvin, McClain	17 min
Apr 28, 12:13 AM CDT	Tornado Warning Tornado observed	OUN	Cleveland, Garvin, McClain, Pottawatomie	32 min
Apr 28, 12:27 AM CDT	Areal Flood Advisory	OUN	Carter, Garvin, McClain, Murray, Stephens	3 hr
Apr 28, 12:47 AM CDT	Flash Flood Warning	OUN	Garvin	8 hr
Apr 28, 12:59 AM CDT	Areal Flood Advisory	OUN	Cleveland, Pottawatomie, Seminole	4 hr
Apr 28, 1:31 AM CDT	Special Weather Statement	OUN	Pottawatomie	29 min
Apr 28, 1:40 AM CDT	Areal Flood Advisory	OUN	Pontotoc, Pottawatomie, Seminole	3 hr
Apr 28, 1:43 AM CDT	Special Weather Statement	OUN	Seminole	32 min
Apr 28, 3:11 AM CDT	Flash Flood Warning	OUN	Carter, Cotton, Jefferson, Murray, Stephens	6 hr
Apr 28, 3:56 AM CDT	Special Weather Statement	OUN	Murray	34 min
Apr 28, 4:09 AM CDT	Special Weather Statement	OUN	Garvin	36 min
Apr 28, 4:25 AM CDT	Severe Thunderstorm Warning	OUN	Carter, Garvin, McClain, Stephens	35 min
Apr 28, 4:27 AM CDT	Special Weather Statement	OUN	Pontotoc	33 min
Apr 28, 5:05 AM CDT	Special Weather Statement	OUN	Hughes	25 min
Apr 28, 5:09 AM CDT	Areal Flood Advisory	OUN	Hughes, Pontotoc, Pottawatomie, Seminole	4 hr
Apr 28, 5:24 AM CDT	River Flood Warning	OUN	Pottawatomie, Seminole	18 hr
Apr 28, 6:19 AM CDT	River Flood Advisory	OUN	Carter, Garvin, Murray	4 hr
Apr 28, 6:33 AM CDT	Flash Flood Warning	OUN	Garvin, Hughes, McClain, Murray, Pontotoc, Pottawatomie and 1 more	4 hr
Apr 28, 8:02 AM CDT	Special Weather Statement	OUN	Murray	28 min
Apr 28, 8:15 AM CDT	Special Weather Statement	OUN	Pontotoc	30 min
Apr 28, 8:33 AM CDT	Severe Thunderstorm Warning	OUN	Hughes, Pontotoc	27 min
Apr 28, 8:47 AM CDT	Special Weather Statement	OUN	Pontotoc	28 min
Apr 28, 8:48 AM CDT	Areal Flood Advisory	OUN	Coal, Hughes, Johnston, Pontotoc	3 hr
Apr 28, 8:56 AM CDT	Special Weather Statement	OUN	Hughes	34 min
Apr 28, 9:03 AM CDT	Flash Flood Warning	OUN	Carter, Garvin, Jefferson, McClain, Murray, Stephens	117 min
Apr 28, 9:14 AM CDT	Flash Flood Warning Considerable damage threat	OUN	Coal, Hughes, Pontotoc, Seminole	3 hr
Apr 28, 9:16 AM CDT	Flash Flood Warning Considerable damage threat	OUN	Coal, Hughes, Pontotoc, Seminole	3 hr
Apr 28, 9:53 AM CDT	River Flood Warning	OUN	Hughes, Seminole	35 hr
Apr 28, 9:56 AM CDT	River Flood Warning	OUN	Carter, Garvin, Murray	13 hr
Apr 28, 9:59 AM CDT	Areal Flood Advisory	OUN	Carter, Jefferson, Johnston, Love, Marshall, Murray	3 hr
Apr 28, 10:46 AM CDT	Flash Flood Warning	OUN	Carter, Johnston, Love, Marshall	4 hr
Apr 28, 11:01 AM CDT	Areal Flood Warning	OUN	Carter, Garvin, Hughes, McClain, Murray, Pontotoc and 2 more	3 hr
Apr 28, 11:39 AM CDT	River Flood Advisory	OUN	Hughes	2 hr
Apr 28, 11:43 AM CDT	Special Weather Statement	OUN	Kay	47 min
Apr 28, 11:59 AM CDT	Special Weather Statement	OUN	Garfield, Kingfisher	31 min
Apr 28, 12:16 PM CDT	Areal Flood Warning	OUN	Coal, Hughes, Pontotoc, Seminole	4 hr
Apr 28, 1:20 PM CDT	Areal Flood Advisory	OUN	Bryan, Marshall	3 hr
Apr 28, 1:31 PM CDT	Areal Flood Advisory	OUN	Cleveland, Grady, McClain, Oklahoma	4 hr
Apr 28, 1:31 PM CDT	Special Weather Statement	OUN	Garfield	29 min
Apr 28, 1:45 PM CDT	Special Weather Statement	OUN	Garfield	30 min
Apr 28, 2:07 PM CDT	River Flood Warning	OUN	Hughes	9 hr
Apr 28, 2:22 PM CDT	Special Weather Statement	OUN	Love	23 min
Apr 28, 2:38 PM CDT	Special Weather Statement	OUN	Canadian	22 min
Apr 28, 2:46 PM CDT	Areal Flood Advisory	OUN	Carter, Johnston, Love, Marshall	3 hr
Apr 28, 3:17 PM CDT	Areal Flood Advisory	OUN	Caddo, Canadian, Grady, Kingfisher, Logan, Oklahoma	3 hr
Apr 28, 3:22 PM CDT	Special Weather Statement	OUN	Logan	23 min
Apr 28, 3:52 PM CDT	Special Weather Statement	OUN	Caddo	23 min
Apr 28, 3:54 PM CDT	River Flood Warning	OUN	Carter, Johnston, Murray	31 hr
Apr 28, 3:56 PM CDT	Areal Flood Advisory	OUN	Caddo, Comanche	3 hr
Apr 28, 4:19 PM CDT	Special Weather Statement	OUN	Lincoln	26 min
Apr 28, 4:21 PM CDT	Special Weather Statement	OUN	Caddo	24 min
Apr 28, 4:23 PM CDT	Special Weather Statement	OUN	Logan, Noble	37 min
Apr 28, 4:48 PM CDT	Special Weather Statement	OUN	Grady	42 min
Apr 28, 4:56 PM CDT	Areal Flood Advisory	OUN	Noble	3 hr
Apr 28, 5:01 PM CDT	Special Weather Statement	OUN	Noble	44 min
Apr 28, 5:23 PM CDT	Special Weather Statement	OUN	Johnston	37 min
Apr 28, 5:36 PM CDT	Severe Thunderstorm Warning	OUN	Atoka, Johnston	24 min
Apr 28, 5:40 PM CDT	Special Weather Statement	OUN	Oklahoma	35 min
Apr 28, 6:02 PM CDT	Special Weather Statement	OUN	Atoka	28 min
Apr 28, 6:26 PM CDT	Special Weather Statement	OUN	Washita	49 min
Apr 28, 6:59 PM CDT	Special Weather Statement	OUN	Caddo	46 min
Apr 27, 7:09 PM CDT	Severe Thunderstorm Warning	OUN	Baylor, Foard, Knox	51 min
Apr 27, 7:44 PM CDT	Severe Thunderstorm Warning	OUN	Baylor, Wilbarger	46 min
Apr 27, 7:53 PM CDT	Tornado Warning	OUN	Wichita	24 min
Apr 27, 7:58 PM CDT	Severe Thunderstorm Warning	OUN	Baylor, Knox, Wilbarger	47 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.