078
FXUS64 KOUN 261738
AFDOUN

Area Forecast Discussion
National Weather Service Norman OK
1238 PM CDT Wed Jun 26 2024

...New AVIATION...

.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...
(18Z TAFS)
Issued at 1233 PM CDT Wed Jun 26 2024

Isolated thunderstorms are possible this afternoon and evening
across parts of southwest and southern Oklahoma near a surface
boundary. Strong to damaging wind gusts are possible with these
storms. Winds are forecast to become predominantly
east/southasterly overnight.

&&

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

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Heat Advisory until 9 PM CDT this evening for OKZ004>016-019-020-
     026-030>032.

     Excessive Heat Warning until 9 PM CDT this evening for OKZ017-
     018-021>025-027>029-033>048-050>052.

TX...Excessive Heat Warning until 9 PM CDT this evening for
     TXZ083>090.

&&

$$

SHORT TERM...10
LONG TERM....10
AVIATION...01