Severe Thunderstorm Warning 621, NWS Norman, OK

Area Forecast Discussion
National Weather Service Norman OK
1105 PM CDT Sun Jun 21 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 1059 PM CDT Sun Jun 21 2026

- Severe thunderstorms producing heavy local rainfall, damaging
  wind gusts and large hail possible tonight associated with a
  cold front passage

- An unsettled pattern with multiple rounds of rain/storms are
  expected through this upcoming week; severe storms and heavy
  rainfall are possible especially late Tuesday

- Below normal temperatures but muggy conditions are forecast
  this week becoming hotter this weekend.

&&

.NEAR TERM...
(Rest of tonight through Monday)
Issued at 1045 PM CDT Sun Jun 21 2026

Strong to severe storms expected overnight as a cold front coming
down from the Central Plains will be pushing through enhanced by a
shortwave disturbance in the mid-level.  With moderate to strong
instability and strong 40-45 kt deep-layer shear will be sufficient
for organized severe storms producing up to 2-in diameter hail
and/or damaging wind downbursts as well as locally heavy rainfall.
Expecting the frontal boundary and storms to reach the OKC Metro
around 2-3 AM and perhaps the Red River by 5 AM.  Behind the surface
boundary a second mid-level shortwave may be following producing a
second round of storms during the latter half of the morning
although weakened instability should keep them sub-severe. Will keep
storm POPs in the forecast for Monday afternoon due to another
potential mid-level shortwave coming down from the northwest ascent
from the cold front boundary which may stall out along the Red
River. Can't completely rule out a potential Heat Advisory for our
Texas counties for Monday afternoon should the cold front stall
along the Red River. Much will depend on where the surface boundary
stalls out by Monday afternoon so the call for a heat advisory will
need to be made closer in time.
 &&

.SHORT TERM...
(Monday night through Tuesday night)
Issued at 1045 PM CDT Sun Jun 21 2026

Surface-based moisture transport will increase in the short term
with the dryline staying far west of our forecast area and our cold
front boundary stalled out near the Red River early in the week.  As
a result instability will be increasing to moderate intensity late
in the day from diurnal heating.  Meanwhile an upper high will be
closing over the U.S. Southwest through adjacent Old Mexico which
will be building a ridge over the Southern Plains.  With the stalled
surface boundary across our south and embedded mid-level shortwave
rounding the ridging across our west and ample surface moisture in
place will maintain storm chances every day in the short term.  A
surface low lee of the Colorado Rockies will be pushing a cold front
across the Central High Plains late Tuesday where severe weather
could initiate and a few of these storms producing large hail &
damaging wind gusts could track into northwest Oklahoma where a
severe risk is in place.  By Wednesday the surface front stalled out
near the Red River may start lifting as a warm front with warm
advection coupled with mid-level disturbances may initiate storm
activity. Although temperatures may be near to slightly below
average, the persisting surface moisture (upper 60s to lower 70s dew
points) will still make our afternoon feel quite hot & muggy but
should stay below heat advisory criteria through week.

&&

.SHORT TERM...
(Monday night through Tuesday night)
Issued at 1045 PM CDT Sun Jun 21 2026

Surface-based moisture transport will increase in the short term
with the dryline staying far west of our forecast area and our cold
front boundary stalled out near the Red River early in the week.  As
a result instability will be increasing to moderate intensity late
in the day from diurnal heating.  Meanwhile an upper high will be
closing over the U.S. Southwest through adjacent Old Mexico which
will be building a ridge over the Southern Plains.  With the stalled
surface boundary across our south and embedded mid-level shortwave
rounding the ridging across our west and ample surface moisture in
place will maintain storm chances every day in the short term.  A
surface low lee of the Colorado Rockies will be pushing a cold front
across the Central High Plains late Tuesday where severe weather
could initiate and a few of these storms producing large hail &
damaging wind gusts could track into northwest Oklahoma where a
severe risk is in place.  By Wednesday the surface front stalled out
near the Red River may start lifting as a warm front with warm
advection coupled with mid-level disturbances may initiate storm
activity. Although temperatures may be near to slightly below
average, the persisting surface moisture (upper 60s to lower 70s dew
points) will still make our afternoon feel quite hot & muggy but
should stay below heat advisory criteria through week.

&&

.LONG TERM...
(Wednesday through next Sunday)
Issued at 1045 PM CDT Sun Jun 21 2026

Our upper pattern will not be changing much in the long term with
embedded shortwaves coming through the ridging.  At the surface our
warm front may be stalling out somewhere near to north of I-40
eventually lifting into the Central Plains by the end of the week
with strong southerly winds coming up into the weekend.  Storm POPs
will be shifting higher across northern Oklahoma late in the week
near the surface boundary with the start of a dry pattern this
weekend along with hotter temperatures returning with triple digit
highs perhaps west of the I-35 corridor.  Overall this weekend is
trending hotter & muggy and dry.

&&

.AVIATION...
(06Z TAFS)
Issued at 1059 PM CDT Sun Jun 21 2026

Two rounds of storms may impact our terminals through the forecast
period degrading our terminals for periods to an MVFR to IFR
category with lowering CB ceilings and reduced visibilities in
heavy rain at times. The first round of strong to severe convection
will be along a cold front & mid-level shortwave coming down the
Central Plains are already moving into northwest Oklahoma reaching
terminals near the I-40 corridor around 07Z and eventually
crossing the Red River into terminal KSPS by 09Z. A second round
of storms will be in association with a second mid- level
shortwave coming off the Southern High Plains which may impact our
terminals again from 12-18Z. Due to some uncertainties with
timing did extend lower probabilities of 30% for storms beyond
18Z. Surface winds will shift northeast behind the cold front but
in actuality expecting surface winds to be gusty and variable in
direction due to the convection and outflow from the storm
activity. Another shortwave MCS may be coming through Monday
evening off Southern High Plains so have 30% probability of storms
returning after 01Z.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  72  83  69  88 /  80  50  60  40
Hobart OK         72  89  69  93 /  50  40  50  20
Wichita Falls TX  76  94  73  96 /  30  40  50  20
Gage OK           67  84  66  91 /  50  30  30  30
Ponca City OK     68  80  66  84 /  70  10  30  50
Durant OK         78  91  75  91 / 100  60  70  40

&&

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

NEAR TERM...68
SHORT TERM...68
LONG TERM....68
AVIATION...68

Preliminary Local Storm Report
National Weather Service Norman OK
143 AM CDT Mon Jun 22 2026

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

0135 AM     Tstm Wnd Gst     5 SW Concho             35.56N 98.04W
06/22/2026  M70 MPH          Canadian           OK   Mesonet

&&

EM

Preliminary Local Storm Report
National Weather Service Norman OK
146 AM CDT Mon Jun 22 2026

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

0111 AM     Hail             8 S Omega               35.75N 98.18W
06/22/2026  E1.00 Inch       Kingfisher         OK   Public

            Report from mPING: Quarter (1.00 in.).

&&

EM

Preliminary Local Storm Report
National Weather Service Norman OK
148 AM CDT Mon Jun 22 2026

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

0140 AM     Tstm Wnd Gst     4 SSW Concho            35.56N 98.04W
06/22/2026  M65 MPH          Canadian           OK   Mesonet

&&

EM

Preliminary Local Storm Report
National Weather Service Norman OK
150 AM CDT Mon Jun 22 2026

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

1251 AM     Tstm Wnd Dmg     Okeene                  36.12N 98.32W
06/22/2026                   Blaine             OK   Fire Dept/Rescue

            Lots of tree damage. Powerline down on
            Highway 51. Radar estimated time.

&&

EM

Preliminary Local Storm Report
National Weather Service Norman OK
157 AM CDT Mon Jun 22 2026

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

0133 AM     Tstm Wnd Gst     3 SE Hobart             35.00N 99.06W
06/22/2026  M62 MPH          Kiowa              OK   ASOS

&&

EM

Preliminary Local Storm Report
National Weather Service Norman OK
203 AM CDT Mon Jun 22 2026

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

0155 AM     Tstm Wnd Gst     2 SSW Minco             35.29N 97.96W
06/22/2026  M67 MPH          Grady              OK   Mesonet

&&

EM