353
FXUS64 KFWD 242320
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
620 PM CDT Fri May 24 2024

...New Aviation, Short Term...

.SHORT TERM... /NEW/
Update:
Scattered thunderstorms have developed as expected across North
Texas, many of which have quickly become severe. As this event
continues to unfold, we`ll monitor outflow boundary interactions
as there may be a localized tornado threat.

Very large hail and damaging winds will continue to be the main
threats through the next several hours. The previous discussion
captures the environment fairly well.

Hernandez

Previous Discussion:
/Today and Tomorrow/

Scattered thunderstorms are expected to develop this afternoon and
evening. Some storms will be severe. Large hail greater than 2
inches, damaging wind gusts of 60-70 mph, and a low tornado threat
will exist.

Mesoscale Setup...
We`re watching several boundaries as we move into the early
afternoon. The first, and most notable, is a cold front moving
south through Oklahoma. It is currently moving through OKC/Lawton
and will continue moving south through the day. Ahead of this, a
weak pre-frontal trough (likely originating from overnight
convection well to our north) extends from Wichita Falls to
Abilene. A dryline is observed over the Big Country near Abilene
and San Angelo that will advance east through the afternoon.
Additionally, a remnant outflow boundary is currently moving
across the Red River in Montague County and extends northeast
toward Arkansas. Overtop of all of this (pun intended), a
shortwave trough is evident on water vapor satellite imagery
that will provide broad mid-level ascent over our area through the
afternoon and evening.

Timing and general convective trends...
As of this writing, the atmosphere over the Metroplex is still
heavily capped. A combination of forced ascent from the boundaries
and surface heating should gradually erode the cap over the next
few hours. The first storms of the day should develop between
~3-4 PM where the cold front intersects the pre-frontal trough.
This is expected to take place northwest of the Metroplex
somewhere between Bowie and Sherman. A few isolated, and elevated,
storms are possible over western Central Texas between 1-4 PM
where the mid-level shortwave trough interacts with the dryline.
We`ve noted a couple convective attempts in this area already
today, but the lack of strong low-level ascent and plentiful dry
air aloft is precluding thunderstorm development for now. Today`s
initial storms should be isolated, but expect the coverage to
gradually increase as we approach sunset, with the most widespread
convective activity taking place between ~7-9 PM. The storms
should also move east/southeast, slowly moving into Central Texas
overnight. Most of the storms will end in the early morning hours,
between about 1-2 AM.

Severe threat and convective mode...
The initial storms that develop will likely become supercells in
rather short order. The modified morning sounding indicates MLCAPE
values near 3500 J/kg, with some model soundings indicating CAPE
values exceeding 4-5000 for some areas later this afternoon. The
large CAPE values are aided by a very warm and moist surface, with
70-75 degree dewpoints extending all the way across the Red River.
Additionally, observed mid-level lapse rates approaching 9 degC/km
are resulting in very "fat" CAPE profiles, particularly within
the hail growth zone. While deep-layer shear isn`t off the charts,
there should be sufficient shear to support both left and right
splitting storms throughout the afternoon and evening.

The very high buoyancy supports the potential for large, some
very large (2-3 inches), hail. While the damaging wind threat
isn`t the highest threat today...dry air in the mid-levels and
precip-loaded storms will allow for damaging wind gusts from any
of today`s storms, particularly this evening and overnight when
cold pools merge and the convective mode becomes more messy. The
low level winds do not indicate a widespread threat or high risk
of tornadoes, however, low LCLs and mesoscale interactions will
locally enhance low-level shear and the tornado potential with the
most intense supercells. Opposite of the wind threat, the threat
of tornadoes will be highest in the late afternoon and early
evening.

We have advertised the potential of severe weather again tomorrow,
however we are less confident of storms in our area tomorrow. It
now appears that they dryline will be well to our west, with most
of the convective activity remaining in western/central Oklahoma.
We won`t go into much detail regarding tomorrow, and will provide
more details in future forecast updates.

Heat and Humidity...
It will be very hot and humid today and tomorrow, regardless of
thunderstorm development. We are forecasting high temperatures in
the low to mid 90s with heat index values in the low 100s both
days. Parts of Central Texas will likely meet our Heat Advisory
criteria (heat index > 105 for 2 days), but we are not confident
enough of which counties will eclipse that mark today. Due to
this, we are not planning on issuing a Heat Advisory at this
time.

Bonnette

&&

.LONG TERM... /Issued 310 PM CDT Fri May 24 2024/
/Next Week/

A brief rain-free interlude will begin the week before a more
active pattern returns.

A shortwave transiting the Central Plains on Sunday will drag a
dryline deep into North and Central Texas, potentially reaching
the I-35 corridor. However, a strong cap and the lack of upper
support will keep the radar scope quiet. Areas to the west of the
boundary will see temperatures soar into the mid and upper 90s,
but with noticeably lower humidity. Areas to the east will have
lower afternoon temperatures, but the humidity will push heat
index values back above 100.

As the Central Plains disturbance departs, it will allow a late-
season front to push south of the Red River. Thunderstorm chances
may return as early as Monday evening as the front moves deeper
into the region. Cooler, albeit near-normal, daytime temperatures
will return by Tuesday with even milder temperatures following
during the cloudier latter half of the week. Although the boundary
will experience gradual frontolysis, daily storm chances will
prevail the remainder of the week as periodic disturbances glide
along the northern periphery of a subtropical ridge. This seasonal
anticyclone will remain anchored over Mexico as meteorological
summer begins next weekend. Its transition to a more poleward
latitude, which brings an end to our spring rainy season,
typically occurs closer to the solstice, which is still weeks
away.

25

&&

.AVIATION... /NEW/
/00Z TAFs/

Concerns...TS occurring within the D10 airspace and will continue
through 03Z. MVFR stratus returns early tomorrow morning.

Major impacts are ongoing due to the thunderstorms surrounding all
Dallas/Fort Worth terminals. Heavy rain, large hail and damaging
winds will be the main concerns with these storms. Improving
conditions are expected beyond 03Z as storms continue moving to
the east/southeast. Storms may be slower to clear across Central
Texas, likely closer to 04-05Z.

VFR conditions are expected much of tonight before a stratus deck
invades from the south closer to sunrise. A low MVFR deck is the
most probable through the morning hours before a gradual
scattering of clouds occurs in the afternoon. Winds tonight and
tomorrow will be out of the southeast.

Tomorrow`s storm chances should stay west/northwest of the D10
airspace with little to no impacts to the TAF sites. Airborne
west traffic, however, may see impacts in the afternoon as
additional dryline convection develops.

Hernandez

&&

.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    73  93  76  97  73 /  50   0   5   0   5
Waco                73  93  75  94  71 /  40   5   5   5   5
Paris               69  89  73  90  68 /  40   5  10   5  10
Denton              69  93  75  96  68 /  30   5  10   0   5
McKinney            70  91  75  94  71 /  40   0  10   0   5
Dallas              72  93  76  97  73 /  50   0   5   0   5
Terrell             70  92  75  92  72 /  50   0   5   0   5
Corsicana           74  93  77  94  74 /  40   0   0   5   5
Temple              73  93  75  95  73 /  40   5   5   5   5
Mineral Wells       69  95  75  98  68 /  20  10  10   0   0

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$