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Area forecast discussion
National Weather Service Fort Worth Texas
630 PM CDT Fri Jul 19 2019



Aviation...
the only aviation weather concern with this taf package will be
some brief MVFR stratus at Waco around sunrise Saturday (similar
to the past several mornings). These ceilings will scatter and
lift quickly with vigorous boundary layer mixing. Otherwise,
expect VFR at all sites through Saturday afternoon with only a few
daytime cu and occasional high clouds.

A breezy south wind will continue through Saturday afternoon in
the 12 to 18 knot range along with some higher gusts.

79

&&



Discussion... /issued 253 PM CDT Fri Jul 19 2019/
we have a couple more hot days to get through over the weekend
before a pattern shift delivers a cold front, thunderstorm
chances, and relatively pleasant temperatures early next week.

An elongated Bermuda high extends across much of the southeastern
US, keeping much of the Southern Plains subsident and seasonably
hot. This trend will continue over the weekend, with hot
conditions and little/no chance for rainfall within the forecast
area. An easterly wave feature does exist on the southern fringes
of the ridge axis that will drift towards the area late Saturday.
However, any convective potential is expected to remain in East
Texas or farther southeast along the Gulf Coast. While high
temperatures will be in the mid and upper 90s, heat index values
will largely be below 105 due to dewpoints mixing into the 60s
each afternoon. Therefore, no formal heat headlines are planned
at this time. In addition, a persistent southerly breeze of 10-20
mph should prevent the heat from feeling terribly oppressive.

Some large-scale changes will begin to take shape late Sunday as
the upper ridge translates westward while becoming strongly
amplified. Meridional flow will essentially extend from northern
Canada all the way southward into the Central Plains along the
eastern periphery of the ridge. This fetch of northerly flow will
send a summertime cold front southward, which should encroach on
our forecast area sometime on Monday. Timing of this feature
remains a bit uncertain as its speed will likely be dependent on
the amount of convection associated with it, as consolidating
outflows could force the effective frontal zone to accelerate
southward.

Convective chances will increase along the front as it enters
North Texas on Monday while encountering moderate instability
amidst modest deep-layer shear. Some multicellular clusters or
line segments may exist along the front while additional elevated
convection remains possible following its initial passage. At
least some low-end potential for a strong/severe storm will exist
(mostly for wind), simply given the instability present coupled
with deep inverted-v profiles within the boundary layer. This risk
is expected to be rather isolated at this time with storms
likely struggling to become organized. Storms will continue
southward with the front headed into Tuesday, where some upglide
above the frontal surface may continued support showers or storms
behind the initial boundary.

Behind the cold front, noticeably cooler and drier air will slowly
filter in through the midweek time period. With the previously
mentioned northerly fetch, the source region of this airmass will
essentially have been Canada. However, it will have undergone
substantial modification prior to reaching this far south. Still,
we should see temperatures as much as 5-10 degrees below normal
(aided by some lingering cloud cover), along with much lower
(possibly upper 50s) dewpoints. With the drier air in place,
lows should be capable of falling into the 60s for a couple of
mornings. By late July standards, next week is shaping up to
rather pleasant as we continue to keep the triple-digit heat at
Bay.

-Stalley

&&

Preliminary point temps/pops...
Dallas-ft. Worth 79 98 78 98 78 / 0 0 0 0 5
Waco 77 97 76 98 75 / 0 0 0 0 0
Paris 76 92 75 93 75 / 0 0 0 5 10
Denton 77 97 77 98 77 / 0 0 0 0 5
McKinney 77 96 77 97 77 / 0 0 0 0 5
Dallas 80 98 79 98 79 / 0 0 0 0 5
Terrell 77 94 77 98 77 / 0 0 0 5 5
Corsicana 77 94 75 94 75 / 0 0 0 5 5
Temple 75 96 74 96 75 / 0 0 0 0 0
Mineral Wells 75 97 74 97 74 / 0 0 0 0 5

&&

Forward watches/warnings/advisories...
none.
&&

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