973
FXUS64 KFWD 222355
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
655 PM CDT Wed May 22 2024

...New Short Term, Aviation...

.SHORT TERM... /NEW/
/Through Thursday/

The most widespread convection in progress this evening exists
across Central Texas, and is in the process of impacting the
Waco/Temple/Killeen area. This activity poses a high-end risk for
all severe hazards, and will continue to advance ESE through
Central and eventually East Texas in the proceeding hours.
Meanwhile, additional isolated convection continues to redevelop
in North Texas near and north of a consolidated outflow boundary
which is presently draped from west to east just south of the I-20
corridor. Ample MUCAPE still exists above this boundary while
ascent continues, and this will allow a marginally severe hail
threat to exist with elevated supercellular activity for a few
more hours across portions of North Texas.

Following an eventual departure of Central Texas convection to the
southeast and some dissipation of North Texas activity as the
environment becomes increasingly overworked, a relative lull in
convection is expected from roughly midnight through early
Thursday morning. The one exception to this may be our
northeastern zones where scattered shower and thunderstorm
activity could persist as warm advection strengthens overnight.
However, mesoscale influences of previous convection and the
aforementioned outflow boundary location could heavily influence
the existence and/or location of this convection. After daybreak,
increased warm advection and dynamic ascent associated with a
subtle mid-level disturbance will result in deeper convection near
and south of I-20. This activity should spread northeast during
the daytime, likely impacting portions of North Texas later in the
afternoon. Due to extreme instability values and shear marginally
supportive of supercells, all hazards will be possible with a
primary threat for large hail and a secondary wind/tornado threat.

-Stalley

&&

.LONG TERM... /Issued 217 PM CDT Wed May 22 2024/
Update:
The long term portion of the forecast, as described below, has not
changed much with additional storms expected Thursday associated
with a lifting front and passing shortwave. It does appear the
atmosphere will need to recover from overnight convection before
additional storms get going, and that the front will have moved
well to the north before large scale lift associated with the
shortwave arrives. The best storm chances will be across North
Texas during the afternoon with storms exiting to the northeast
late Thursday evening. Plenty of moisture and instability will
remain in place and there should be adequate deep layer shear to
sustain updrafts. The difficult part will be determining just
where convection will initiate Thursday since there will be no
well-defined sources of low level convergence. Therefore, we will
keep chance PoPs in the forecast for now. Some storms will be
strong to severe with large hail being the primary threat. The
threat for localized flooding will also remain through the
afternoon.

The remainder of the week through the weekend will be hot and
humid with only some low afternoon/evening storm chances. It still
appears that another cold front will enter the region Sunday
night/Monday, resulting in drier and slightly cooler weather for
Memorial Day.

79

Previous Discussion:
/Thursday Onward/

A meandering surface front and a dryline will provide focus for
thunderstorm development again on Thursday as a modest shortwave
trough passes overhead. Recent CAM guidance has indicated that
showers and storms may begin developing Thursday morning across
Central Texas as forcing for ascent strengthens in advance of the
disturbance, likely on the nose of a strong theta-e ridge. Morning
showers and storms would likely be elevated in nature, making hail
the main concern in any strong or severe storm. Convection would
then develop farther north in the vicinity of the aforementioned
surface boundaries as the atmosphere destabilizes Thursday
afternoon.

Models have been less aggressive with the Thursday convection
compared to previous suites, perhaps a result of the atmosphere
being worked over from Wednesday night storms or cloud cover
associated with the Thursday morning activity. In addition, a
persistent capping inversion around 850mb may also be a mitigating
factor. Will keep POPs in the chance to slight chance category
for now, with the best chances across Central Texas in the morning
and North Texas in the afternoon. Any storm which forms
(particularly in the afternoon and evening) could become severe
with large hail and damaging winds; and locally heavy rain may
also occur.

Precipitation will come to an end Thursday night, followed by hot
and humid weather on Friday as the front lifts well north of the
region. A strong shortwave in the Plains will drag the dryline
east to near the I-35 corridor, which may serve as a focus for
isolated thunderstorms Friday afternoon and evening. Storm
coverage would likely remain low, but a highly unstable airmass
and strong flow aloft would allow any storm which forms to once
again become severe. The dryline will remain the main focus for
development on Saturday afternoon and evening as a stronger
shortwave crosses the Southern Plains. A strong cap will be in
place, but a few cells will likely break through it and quickly
become severe. The best chances for storms on Saturday appears at
this time to be along and north of I-20, and in the afternoon and
evening hours.

A lull in storm chances is then expected on Sunday as subsidence
briefly dominates in the wake of the Saturday system. It will
remain quite warm with highs ranging from the low 90s in the
northeast to the upper 90s across the west. Sunday may end up
being the warmest day temperature-wise, but lower dewpoints will
be in place compared to Friday and Saturday (when heat indices
will reach 100+ across most of the CWA).

The next upper level system will drop southeast from
Nebraska into Arkansas/Missouri Sunday night and Monday, dragging
a cold front south through the entire region. Weak forcing will
keep storm chances fairly low and limited to the eastern half of
the region. Otherwise, cooler air will arrive on Memorial Day with
the cold front, bringing near-normal temperatures to North and
Central Texas Monday night through the midweek period of next
week.

30

&&

.AVIATION... /NEW/
/00z TAFs/

Isolated thunderstorms continue to impact portions of D10 early
this evening with strong elevated instability present above an
outflow boundary from previous convection. TS activity at the D10
terminals remains possible through late evening, but mostly quiet
weather is expected overnight before additional thunderstorm
chances resume by mid morning Thursday. An intrusion of MVFR
stratus is also expected overnight, with cigs at or below 2 kft
expected to overspread all airports for severals hour through
daybreak. Additional convective development is likely across D10
through peak heating, and a few hours of strong thunderstorms are
expected in the vicinity the TAF sites during the mid/late
afternoon period.

For Waco, much more widespread strong/severe convection is in
progress at the TAF site as of this writing, and will continue
for the next few hours before vacating the terminal to the
southeast around midnight. MVFR cigs will fill in afterwards, with
additional TS development likely to affect the TAF site tomorrow
morning into the early afternoon hours.

-Stalley

&&


.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    71  86  73  93  73 /  40  40  20   5  20
Waco                72  87  73  91  72 /  90  40  10  10  20
Paris               68  83  68  89  68 /  60  40  50   5  30
Denton              68  85  71  91  69 /  40  40  10   5  10
McKinney            70  84  71  91  70 /  40  40  20   5  20
Dallas              70  87  73  93  72 /  40  40  20   5  20
Terrell             70  85  72  91  71 /  60  40  20   5  20
Corsicana           73  88  75  92  73 /  70  30  20   5  20
Temple              72  89  73  92  72 /  70  30   5  10  10
Mineral Wells       70  85  71  93  69 /  40  40   5   5  10

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
Flood Watch through late Thursday night for TXZ092>095-102>107-
117>123-130>135-141>148-156>161.

&&

$$