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226
FXUS64 KFWD 242010
AFDFWD

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

...New Long Term...

.SHORT TERM... 
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/Issued 114 PM CDT Fri May 24 2024/
/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
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&&

.LONG TERM... 
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/NEW/
/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
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&&

.AVIATION... 
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/Issued 114 PM CDT Fri May 24 2024/
/18Z TAFs/

MVFR ceilings have stuck around longer than expected, but still
expect the stratus to lift/scatter over the next 1-2 hours.

The main impact to aviation today will be thunderstorms that
develop over the next several hours. A few isolated storms will be
possible SW of D10 that may create deviation in the Glen Rose
cornerpost through about 20Z.

More storms are expected to develop after 20-21Z, northwest of
D10 that become more widespread as we continue into the evening.
It is now more likely than not that direct D10 impacts take place,
mainly between 22-02Z this evening. There is potential for large
hail and erratic wind gusts of 50 kts with this activity. Storms
should then move south and east after 02-03Z, with all storms
ending around 06Z tonight. In general...the northern cornerposts
will likely be impacted first, then D10 itself, then the southern
cornerposts overnight.

Another round of MVFR stratus is expected tonight while gusty
south flow prevails for much of the TAF period.

Bonnette
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&&

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

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

$$