Drought in Oklahoma, June 20 to 26, 2023

Area Forecast Discussion
National Weather Service Norman OK
1043 PM CDT Mon Jun 19 2023

...New AVIATION...

.SHORT TERM...
(This evening through Tuesday)
Issued at 252 PM CDT Mon Jun 19 2023

From the atmosphere that brought us "May in June", we now present:
"heat". The unseasonably low heights aloft and persistent flow
have finally been replaced by our old friend the subtropical
ridge, which extends in a positive tilt from northern Mexico to
the Great Lakes region. A shortwave trough embedded in what
remains of the subtropical jet will round the northward side of
the ride core this evening and drop southeastward across the east
side of our area. It will encounter an environment characterized
by extremely high boundary-layer moisture as south central
Oklahoma remains in the influence of the record-setting Gulf
airmass. Thus, MUCAPE in excess of 4,000 J/Kg can be expected even
by daybreak as the shortwave approaches. 12Z HREF members suggest
that this may be enough to kick off the development of scattered
storms east of I-35, which will drop southeastward through
southeast Oklahoma and dissipate around daybreak. Marginally
severe hail certainly seems possible given the strong instability
and more than sufficient shear for elevated convection. Otherwise,
lows tonight will drop into the low 70s area- wide.

Tomorrow looks like the peak of our mini-June-heatwave, so to speak.
Similar to today, a weak surface low will develop in the lee of the
Caprock Escarpment across western north Texas, bringing downslope
southwesterly surface winds into an environment that will be
characterized by extreme boundary layer mixing ratios. The result
will be similar to today, except a little bit hotter with slightly
higher 500 mb heights as the ridge strengthens. Heat indices will
range from around 110 in western north Texas and southwest Oklahoma,
to the upper 100s in southeast Oklahoma where the greatest moisture
is, to "only" the low 100s across most of the rest of Oklahoma. A
slight southeast breeze will help keep WBGT risks from reaching
extreme levels across most of the area, but it will still be one to
watch among vulnerable populations, especially in Payne County where
power outages continue after recent storms.

Meister

&&

.LONG TERM...
(Tuesday night through next Sunday)
Issued at 252 PM CDT Mon Jun 19 2023

A similar surface pattern will exist on Wednesday as a small lee
trough/low sets up in western north Texas, allowing moisture
advection followed by strong downslope heating. Temperatures should
come down a degree or two as a deep trough over the Southeast
retrogrades slightly westward, eroding the east side of the
subtropical ridge. Will defer heat headline decisions to the
overnight shift for the day on Wednesday, but it looks like they
might only be necessary in western north Texas and far southwest
Oklahoma.

Storms are possible Wednesday night, as some of the more reliable
longer-range guidance like the RRFS shows convection blowing up
along the Texas panhandle dryline as easterly winds slosh moisture
onto the higher terrain. This will likely make it into our western
counties after about 8:00 pm. MLCAPE values in excess of 3,500 J/kg
and about 50 knots of bulk shear will exist ahead of this complex,
in addition to 1,400 J/kg of DCAPE. All of this suggests the risk
for an organized MCS to impact western Oklahoma and western north
Texas Wednesday evening with some risk for damaging wind gusts.

The mini-heatwave will conclude on Thursday as northwest flow
continues to edge into the area. Given the continued very high
atmospheric moisture content and northwest flow aloft, this would
seem to be an ideal setup for an MCS to dive south into our area out
of Kansas. Indeed, the GFS and NAM both suggest that, although
differences exist in timing. However, ensembling all available
guidance within the NBM suggests a minimal chance for precipitation
across most of our area Thursday. Will let the NBM ride for now, but
monitoring this period as a potential target of opportunity. Given
deep moisture, this would unlikely be as impactful an MCS as what we
experienced this past Thursday or Saturday nights. However, trends
for severe and/or flooding will be monitored.

Northerly flow aloft on Friday will keep temperatures near-average
and humid. The ridge will build back in for the weekend, and heat
headlines may be possible again.

Meister

&&

.AVIATION...
(06Z TAFS)
Issued at 1040 PM CDT Mon Jun 19 2023

Mainly VFR conditions are expected this period, with scattered to
at times broken MVFR ceilings possible, especially across western
Oklahoma and north-central Oklahoma overnight through mid-morning
Tuesday. Otherwise, southeasterly winds will remain nearly steady
around 10-12 knots.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  93  73  94  74 /   0  10   0  10
Hobart OK         99  71  98  74 /   0  10   0  10
Wichita Falls TX 103  75 102  76 /   0  10   0   0
Gage OK           96  68  97  70 /   0   0   0  10
Ponca City OK     92  71  93  70 /   0   0   0  10
Durant OK         94  74  96  74 /   0  30  20  10

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Heat Advisory from 1 PM to 9 PM CDT Tuesday for OKZ027-036>041-
     043>048-050>052.

TX...Heat Advisory from 1 PM to 9 PM CDT Tuesday for TXZ085-086-
     088>090.

&&

SHORT TERM...04
LONG TERM....04
AVIATION...08

Hazardous Weather Outlook...UPDATED
National Weather Service Norman OK
1109 PM CDT Mon Jun 19 2023

OKZ004>048-050>052-TXZ083>090-210415-
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-
1109 PM CDT Mon Jun 19 2023

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

.DAY ONE...Tonight...

.Thunderstorms...
A few thunderstorms are possible late tonight across southeastern
and central Oklahoma. One or two strong to severe thunderstorms
will be possible, with large hail up to the size of quarters the
main hazard.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday...

.Heat...
Heat index values from 100 to 114 degrees are forecast Tuesday
and Wednesday and again Saturday and Sunday.

.Thunderstorms...
A few strong to severe thunderstorms will remain possible across
southeastern OK early Tuesday morning. Thunderstorm chances
then return to western Oklahoma and north TX Wednesday and
Thursday night. A few strong to severe storms will be possible,
with damaging wind gusts and hail up to the size of quarters the
main hazards.

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