472
FXUS64 KFWD 221812
AFDFWD

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

...New Aviation...

.SHORT TERM... /Issued 1109 AM CDT Wed May 22 2024/
/This afternoon through Tonight/

Active weather is expected over the next 48 hours, but we will
highlight the fist 18 to 24 hours in this portion of the
discussion. Very humid air is currently in place across the
entire region this morning with middle and upper 70s dew points.
The 12Z sounding showed a very unstable and largely uncapped
environment which will support thunderstorms. The other two
ingredients necessary for strong to severe storms are lift and
shear and we already have enough deep layer shear to support
long-lived updrafts. Large scale lift will be provided by subtle
shortwave energy moving through southwest flow aloft. However, the
more important and much stronger forcing for ascent will accompany
a southward moving cold front. The front is currently sliding
through the northwest zones and will continue its southward
progression through the afternoon. Storms will develop along the
front with most CAMs showing initiation across North Texas around
noon and based on the current radar, that may be a bit slow. Once
the first storms develop, the interaction of outflow boundaries
with the favorable storm environment will result in a combination
of storm modes with a potential for discrete supercells as well as
storm clusters. All modes of severe weather will be possible this
afternoon with large hail being the primary hazard. However, any
mesoscale induced, backed, low level flow could result in a brief
tornado or two. Storms may become more organized into a complex
late this afternoon and evening with mergers from storm moving off
of the dryline west of the forecast area. Our Central Texas
counties will be the most likely place for this to occur and
should it happen, the damaging wind threat will increase. Storm
chances will decrease overnight with the exiting shortwave, but
the front and multiple outflows will linger across the region,
becoming a focus for additional storms on Thursday (as highlighted
in the long term discussion).

Since moisture will not be confined to just the boundary layer,
many storms will be heavy rain producers. The good news is that
steering flow should keep storms moving, but there will be
potential for brief but heavy downpours and storm training.
Therefore, flooding will be possible and with more storms expected
Thursday, we will keep a Flood Watch in effect for much of the
forecast area.

Clouds and rain-cooled air will keep afternoon highs generally in
the 80s, except for some lower 90s across Central Texas. High
humidity will keep overnight lows mainly in the 70s, except for
near the Red River where the post-frontal air will be slightly
drier and cooler.

79

&&

.LONG TERM... /Issued 307 AM CDT Wed May 22 2024/
/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/
/18Z TAFs/

Thunderstorms will temporarily impact all TAF sites this afternoon
with the best window of time for storms at the Metroplex
terminals between 18Z and 23Z. Thunderstorms could linger in the
vicinity beyond 23Z, especially in Waco. All storms should exit to
the east or northeast with a passing shortwave overnight, but
additional storms will be possible Thursday afternoon.

MVFR to low end VFR ceilings are expected through the afternoon
with improvements to VFR during the evening. MVFR/IFR ceilings
will return overnight and prevail through much of the morning
Thursday along with reduced visibility in mist.

A south wind to start the TAF cycle will temporarily turn to the
northeast/east behind a cold front at the Metroplex TAF sites.
The wind will turn back to the south/southeast this evening.
Sustained wind speeds will stay in the 7 to 13 knot range overall.
However, much stronger, gusty, and erratic winds are likely in and
near any thunderstorm.

79

&&


.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    86  71  86  74  93 /  60  50  40  20   5
Waco                87  72  87  74  91 /  40  50  30  10  10
Paris               80  67  83  68  88 /  80  60  50  50   5
Denton              84  68  85  71  92 /  70  50  50  10   5
McKinney            83  68  85  72  91 /  60  50  50  20   5
Dallas              85  70  87  73  93 /  60  50  40  20   5
Terrell             85  69  86  72  90 /  60  50  40  20   5
Corsicana           88  73  89  75  92 /  40  50  30  20   5
Temple              90  73  90  74  92 /  30  40  30   5  10
Mineral Wells       87  69  87  72  93 /  60  40  30   5   5

&&

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

&&

$$