Severe Thunderstorm Warning 421, NWS Norman, OK

Area Forecast Discussion
National Weather Service Norman OK
1049 PM CDT Sat Jun 20 2020

...New AVIATION...

.SHORT TERM...
(This evening through Sunday morning)
Issued at 127 PM CDT Sat Jun 20 2020

POPS were diminished for today, especially in southeastern
Oklahoma in the subsidence region of the MCV moving into SE OK
this afternoon. Other than isolated showers, thunder and rain
isn't expected until late this evening and early Sunday when
moderate warm advection is expected to form from western TX into
southwestern into a region of mass convergence. Scattered showers
and thunderstorms are expected from there toward central Oklahoma
before sunrise.

&&

.LONG TERM...
(Sunday night through next Friday)
Issued at 341 PM CDT Sat Jun 20 2020

As a dryline moves eastward Sunday evening through western Kansas
and Oklahoma/Texas panhandles, storms are expected to develop ahead
of the dryline and move into western and northern Oklahoma.
Development of these storms is coincident with the movement of a
upper-level shortwave trough northern Oklahoma, which with the ample
shear and instability will result in a higher chance of severe
weather. The main concern with these storms will be strong winds and
large hail, and while the lower level shear isn't anything
spectacular, tornado chances can't be ruled out.

While the severe potential diminishes overnight Sunday into
Monday, precipitation chances will continue through northern and
central Oklahoma Monday afternoon and evening. A cold front will
begin to move through northwestern Oklahoma Monday night, and
widespread precipitation will move through the region Monday
night into Tuesday. Severe potential for this round of
precipitation should remain low, with higher chances in area with
higher instability in southern Oklahoma and western north Texas.

Storm chances will continue throughout the remainder of the week,
however storms should remain fairly isolated/scattered. Ample
moisture advection at the surface will continue through the week,
while numerous short wave troughs through the region will provide
some focus for storm development.

Zwink

&&

.AVIATION...
(06Z TAFS)
Issued at 1046 PM CDT Sat Jun 20 2020

Widely scattered showers and thunderstorms will continue to
develop overnight mainly south of I-40. Another area where storms
may move into will be NW OK near WWR around 07Z but confidence is
lower there, as storms moving out of KS may weaken before making
it that far south. Since it appears coverage should remain below
50% for most of the night, have only included VCTS at many of the
terminals. LAW and SPS may be amended later to include a tempo for
TSRA.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  68  89  72  90 /  40  30  30  10
Hobart OK         68  94  72  96 /  40  10  20  10
Wichita Falls TX  71  95  74  98 /  40  20  10   0
Gage OK           65  92  67  93 /  10  20  30  10
Ponca City OK     68  89  69  90 /  20  20  70  30
Durant OK         71  89  72  92 /  50  60  10  10

&&

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

SHORT TERM...09
LONG TERM....50
AVIATION...03

Hazardous Weather Outlook
National Weather Service Norman OK
811 PM CDT Sat Jun 20 2020

OKZ004>048-050>052-TXZ083>090-211130-
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-
811 PM CDT Sat Jun 20 2020

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

.DAY ONE...Through tonight...

.Thunderstorms...
Scattered strong to severe thunderstorms may develop
across parts of southern Oklahoma and western north Texas mainly
after 10 pm. If storms develop they will move northward into
parts of central Oklahoma during the overnight hours. Hail up to
the size of half dollars and wind gusts to 60 mph are possible
with the stronger storms. Heavy rainfall rates with thunderstorms
may result in minor flooding as well.

Elsewhere, a few strong thunderstorms over Kansas may move into
northern Oklahoma late this evening and overnight.

.SPOTTER AND EMERGENCY MANAGEMENT STATEMENT...

Storm spotter groups and emergency management personnel across
southwestern Oklahoma and western north Texas should be ready
for severe weather operations after 10pm and into the overnight
hours.

.DAYS TWO THROUGH SEVEN...Sunday through Friday...

.Thunderstorms...
Severe storm potential increases on Sunday, with the highest
chances of storms in northern Oklahoma late Sunday into Monday.
Storms developing in Kansas will move southeastward into the area,
and are expected to develop into multiple lines. Damaging winds
and large hail are the primary concerns, however a tornado could
also be possible.

Severe chances continue Monday night into Tuesday, with severe
potential greatest in northern Oklahoma as another line of storms
enter the area. Large hail and damaging winds are the main
concern.

Storm potential continues through the remainder of the week.

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

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
200 AM CDT Sun Jun 21 2020

OKZ005>007-210730-
Alfalfa OK-Woods OK-Grant OK-
200 AM CDT Sun Jun 21 2020

...SIGNIFICANT WEATHER ADVISORY FOR northern Alfalfa...northeastern
Woods and northern Grant Counties Until 230 AM CDT...

AT 157 AM CDT, the leading edge of strong and gusty thunderstorm
winds extended along a line extending from 9 miles east of
Manchester to 3 miles south of Hardtner Kansas, moving southeast at
30 MPH. Strong and gusty winds will be possible in these areas.

HAZARDS INCLUDE...
Wind gusts to 50 MPH...

LAT...LON 3682 9746 3677 9746 3668 9853 3699 9879
      3700 9772
TIME...MOT...LOC 0657Z 317DEG 25KT 3702 9787 3696 9866

..speg.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
203 AM CDT Sun Jun 21 2020

OKZ045-210730-
Jefferson OK-
203 AM CDT Sun Jun 21 2020

...SIGNIFICANT WEATHER ADVISORY FOR south central Jefferson County
Until 230 AM CDT...

AT 202 AM CDT, a strong thunderstorm was located near Terral, moving
east at 15 MPH.

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

LAT...LON 3388 9797 3391 9798 3391 9797 3393 9795
      3394 9797 3399 9795 3408 9777 3394 9773
      3394 9776 3391 9776 3392 9778 3389 9779
      3390 9779 3386 9783 3385 9787
TIME...MOT...LOC 0702Z 257DEG 11KT 3391 9797

..speg.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
214 AM CDT Sun Jun 21 2020

OKZ004-210745-
Harper OK-
214 AM CDT Sun Jun 21 2020

...SIGNIFICANT WEATHER ADVISORY FOR northwestern Harper County Until
245 AM CDT...

AT 214 AM CDT, a strong thunderstorm was located on the Kansas-
Oklahoma border northwest of Buffalo, moving south at 20 MPH.

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

LAT...LON 3700 9967 3677 9958 3673 9991 3700 9992
TIME...MOT...LOC 0711Z 350DEG 18KT 3700 9980

..speg.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
225 AM CDT Sun Jun 21 2020

OKZ044-045-210800-
Cotton OK-Jefferson OK-
225 AM CDT Sun Jun 21 2020

...SIGNIFICANT WEATHER ADVISORY FOR east central Cotton and
northwestern Jefferson Counties Until 300 AM CDT...

AT 221 AM CDT, a strong thunderstorm was located near Hastings,
moving east at 10 MPH.

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

LAT...LON 3413 9809 3413 9810 3415 9810 3415 9813
      3413 9815 3414 9818 3424 9819 3427 9793
      3410 9793
TIME...MOT...LOC 0721Z 282DEG 7KT 3419 9813

..speg.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
226 AM CDT Sun Jun 21 2020

OKZ038-044-210800-
Cotton OK-Comanche OK-
226 AM CDT Sun Jun 21 2020

...SIGNIFICANT WEATHER ADVISORY FOR northwestern Cotton and south
central Comanche Counties Until 300 AM CDT...

AT 225 AM CDT, a strong thunderstorm was located near Chattanooga,
moving east at 25 MPH.

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

LAT...LON 3433 9861 3434 9866 3446 9866 3452 9838
      3430 9838 3428 9861
TIME...MOT...LOC 0725Z 259DEG 22KT 3437 9864

..speg.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
239 AM CDT Sun Jun 21 2020

OKZ045-210815-
Jefferson OK-
239 AM CDT Sun Jun 21 2020

...SIGNIFICANT WEATHER ADVISORY FOR south central Jefferson County
Until 315 AM CDT...

AT 235 AM CDT, a strong thunderstorm was located 4 miles northeast of
Terral, moving east at 10 MPH.

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

LAT...LON 3387 9792 3395 9796 3399 9795 3400 9796
      3406 9778 3394 9774 3393 9776 3391 9776
      3392 9778 3389 9778 3389 9779 3390 9780
      3388 9780
TIME...MOT...LOC 0735Z 250DEG 7KT 3394 9789

..speg.