NWS Area Forecast Discussion

FXUS64 KFWD 202037

Area Forecast Discussion
National Weather Service Fort Worth TX
337 PM CDT Thu Jun 20 2019

/Through Tonight/

The main highlight in the short term is the heat across most of
North and Central Texas this afternoon. A Heat Advisory remains in
effect for most of the region until 8 PM this evening. As of the
time of this writing, heat index values have ranged from 105 to
110 degrees. Continue to take the necessary heat precautions
through this evening as heat index values will remain in the upper
90s and low 100s through the late evening hours.

A low potential for thunderstorms remains across the far western
counties this afternoon and evening. The latest METARs reveal a
sharp decrease in dewpoints across the Big Country... from the
upper 40s near Sweetwater and points westward to the upper 60s and
70s near Abilene and points eastward. While CAMs are not
initiating any convection near or along the dryline, it is
possible given the hot afternoon temperatures may approach the
convective temperature. Model soundings reveal some CIN, but
should anything develop, a downburst wind threat will exist.
Maintained a mention of slight chance PoPs to account for this
potential through this evening.

Otherwise, a low level jet will ensue overnight and abundant low
level moisture will continue to filter in. This will result in
increasing cloud cover, mainly along and east of the I-35
corridor. Overnight low temperatures will be in the upper 70s,
well above seasonal normals for mid June.



/Through Next Week/

Muggy, unpleasant conditions persist into Friday as a building
ridge aloft keeps heat and humidity squarely over North and
Central Texas. Once low-level clouds mix/dissipate during the
morning hours, plentiful insolation and dew points well into the
70s should support heat indices approaching 105 or even higher, on
the back of temps climbing into the 90s. A heat advisory may be
needed again for Friday, but after collaboration with surrounding
offices, uncertainty in the location of the highest heat indices
precludes an extension at this time.

Although there is a very low possibility of a shower or
thunderstorm developing across western areas during peak heating,
dry air aloft and a lack of large-scale ascent should keep
convection at bay Friday afternoon and evening.

Into the weekend, high temperatures and heat indices will be
slightly more manageable, thanks to a longwave trough and
embedded disturbances encroaching on the southern Plains.
Regardless, ample boundary-layer moisture, characterized by 70s
dew points, will continue to flow northward across our region
uninhibited. With temperatures aloft cooling some, convection
should form more readily over west Texas and Oklahoma Saturday
afternoon into the overnight. 30-40 kt of southerly 850mb flow may
bring a complex towards the Red River overnight, although it will
be battling nocturnal inhibition. Still, at least some convection
should cross the river, and PoPs may need to be increased further
in later forecasts.

Thunderstorm chances increase Sunday into Monday as we sit
underneath west/southwesterly flow near the base of the
aforementioned trough. Prior convection should slowly shift an
outflow boundary south, resulting in renewed development during
the day Sunday and then especially Sunday night into early Monday.
Somewhat unidirectional flow could yield an upshear-developing
complex that sinks south across parts of North and perhaps Central
Texas. The severe threat does not look overly concerning at this
time, but adequate deep-layer shear and instability may be
sufficient for at least locally strong/severe storms during this
timeframe. Additionally, training convection could re-aggravate
flooding concerns.

After Monday, conditions should become considerably quieter as the
trough shifts east and a ridge builds to our west. We`ll stay
muggy with weak southerly flow at the surface, but high
temperatures should stay in check some (i.e., upper 80s to low/mid
90s) thanks to areas of weakness on the eastern side of the



.AVIATION... /Issued 1248 PM CDT Thu Jun 20 2019/
/18Z TAFs/

VFR and southerly winds will prevail through the afternoon and
evening hours. There remains a low potential for thunderstorms
late this afternoon, but should not impact the TAF sites. MVFR
stratus is expected to develop overnight with the aid of a 30 knot
low level jet and impact ACT close to 11Z. High res guidance has
hinted at the possibility of the stratus spreading northward
towards the Metroplex sites, but confidence is too low to warrant
a mention in the TAF at this time.

By late morning Friday, VFR will prevail once again at all sites.
An uptick in southerly winds is expected Friday, with gusts close
to 25-30 knots possible.



Dallas-Ft. Worth    79  95  77  93  76 /  10   0   5  10  20
Waco                78  96  78  94  76 /  10   0   5  10  10
Paris               76  92  76  91  74 /  10   5   5  10  20
Denton              77  95  77  92  75 /  10   0   5  10  20
McKinney            78  94  77  92  75 /  10   0   5  10  20
Dallas              79  96  78  93  76 /  10   0   5  10  20
Terrell             78  95  77  93  76 /  10   0   5  10  10
Corsicana           77  95  76  94  75 /  10   0   5  10   5
Temple              78  95  78  94  76 /  10   0   5  10  10
Mineral Wells       76  96  74  93  74 /  10   0   5  10  20


Heat Advisory until 8 PM CDT this evening for TXZ091>094-100>105-




NWS FWD Office Area Forecast Discussion