263
FXUS64 KOUN 260843
AFDOUN

Area Forecast Discussion
National Weather Service Norman OK
343 AM CDT Wed Jun 26 2024

...New SHORT TERM, LONG TERM...

.SHORT TERM...
(Today and tonight)
Issued at 342 AM CDT Wed Jun 26 2024

Thunderstorms across Northeast Oklahoma may clip east central
into southeast Oklahoma as they move southward this morning.
Otherwise, dangerously hot conditions are expected once again
across Oklahoma and north Texas. A boundary will advance southward
and will be located near I-40 during the afternoon with weak
surface confluence. Unfortunately, no noticeably cooler air mass
is expected behind this boundary. Temperatures may actually be a
little higher along and ahead of the boundary as 850 mb
temperatures are progged to be higher than yesterday.

As a result, forecast highs range from the upper 90s to upper
100s deg F. Combined with dew points in the low to mid 70s deg F,
dangerous heat indices from 105 to 115 deg F are expected. In
addition, winds will be lighter than yesterday, so the wet bulb
globe temperature risk has a high probability to reach the extreme
risk category. In the extreme risk category, working or
exercising in direct sunlight will stress your body in about 15
minutes. Opted to expand to Excessive Heat Warning farther north
to include the Oklahoma metro and points to the east given higher
confidence that heat indices will reach 110 deg F or higher in
this area.

While synoptic-scale ascent appears nebulous, confluence along
the boundary and daytime heating may be sufficient for isolated
thunderstorms in an uncapped atmosphere (which is in agreement
with some convective-allowing and parameterized models). The area
to watch development for would be near or just south of the
boundary during the late afternoon and evening hours with a 20 to
30% chance. If thunderstorms develop, damaging wind gusts are
possible given the large downdraft CAPE (~1600 J/kg). Large hail
is also possible given the deep buoyancy, weak low-level shear,
and modest effective bulk layer shear. Additional thunderstorms
may also move in from the Texas panhandle later in the evening
hours.

Mahale

&&

.LONG TERM...
(Thursday through Tuesday)
Issued at 342 AM CDT Wed Jun 26 2024

Thursday-Friday: The mid-level ridge will become elongated west-
to-east across the southern half of the United States with
northern Oklahoma on the southern periphery of stronger mid-level
flow. The remnants of thunderstorm complexes may approach northern
Oklahoma Thursday night into Friday morning and Friday night in
Saturday morning. While the most intense part will likely stay to
the north, some thunderstorms with strong winds may make into
Oklahoma.

Saturday-Sunday: A mid-level trough will move across the Great
Lakes region with a trailing cold front advancing southward across
the Plains. The cold front will bring a chance for showers and
thunderstorms with the highest chance across northern Oklahoma
late Saturday into Sunday morning.

There remains uncertainty/ensemble spread on how far south the
cold front will advance and the magnitude of the cool down for
Sunday. Probabilistic guidance has a 10 to 15 deg F range for
high temperatures on Sunday (using the 10th and 90th percentiles).
The magnitude of the cool down may end up being highly dependent
on the amount of precipitation and cloud cover. Currently, the
most likely scenario is northern Oklahoma seeing highs in the
upper 80s to low 90s and western north Texas/southern Oklahoma
seeing highs in the upper 90s and low 100s deg F.

Monday-Tuesday: Any cool down will likely be brief as
temperatures are forecast to rise early next week with a
strengthening mid-level ridge and attendant low-level thermal
ridge.

Mahale

&&

.AVIATION...
(06Z TAFS)
Issued at 1211 AM CDT Wed Jun 26 2024

Ongoing thunderstorms with variable gusty winds in their wake should
gradually diminish over the next few hours, unlikely to impact any
more TAF sites. Outside of convection, south winds continue until
a front moves into northern Oklahoma this morning, bringing east
to northeasterly winds behind it. This front is expected to stall
around I-40 by early afternoon. Additional thunderstorms are
possible this afternoon and evening, but confidence is too low for
mention in the TAFs at this time.

Day

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 102  75  97  79 /  20  10  10   0
Hobart OK        106  75 103  81 /  30  30   0   0
Wichita Falls TX 105  78 103  81 /  10  20   0   0
Gage OK          102  73 101  79 /   0  20  10  20
Ponca City OK     99  71  94  78 /  10  10  10  10
Durant OK         99  75  97  78 /  20  20   0   0

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Heat Advisory from 11 AM this morning to 9 PM CDT this evening
     for OKZ004>017-021-022.

     Excessive Heat Warning from 11 AM this morning to 9 PM CDT this
     evening for OKZ018>020-023>048-050>052.

TX...Excessive Heat Warning from 11 AM this morning to 9 PM CDT this
     evening for TXZ083>090.

&&

$$

SHORT TERM...10
LONG TERM....10
AVIATION...14