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Area forecast discussion 
National Weather Service Fort Worth Texas
337 am CDT Friday Jul 29 2016

Discussion...
convective activity ongoing across northern OK and southern Kansas
early this morning will be the main forecast concern for today.
This convective cluster continues to be pushed southeastward by
northwest steering flow aloft of around 40kts. It has been
sustained by a combination of diffluent flow aloft as well as low-
level warm advection and moisture transport which can be seen via
850mb objective analysis. Low level wind fields are stronger
across western OK and the Texas Panhandle and begin to veer and
weaken to the east. This should cause an overall downward trend in
coverage and intensity of this activity as it works southward
toward the Red River early this morning. The hrrr seems far too
bullish on ushering this complex into North Texas and have largely
disregarded its solution in this forecast. However, some remnant
activity from this complex in our northern counties along the Red
River cannot be ruled out thus have continued low pops throughout
the morning and afternoon.

Even if this morning's activity is not sustained into north TX,
outflow boundaries from this convection could set up across our
northern areas this afternoon resulting in new convection. In
addition, a southward-moving boundary from earlier convection
could be vaguely identified on radar and via surface obs draped
roughly from Norman OK to Fort Smith Arkansas as of 3am. This boundary
may also be an additional focusing mechanism for any additional
activity this afternoon. Our area remains under a weakness aloft
today with a deformation axis stretching roughly from del Rio Texas
to Jackson MS. While precipitable water values are less than the past few days,
they will still be above seasonal averages at 1.7-2". Cannot rule
out an isolated shower or storm this afternoon across most of
north and central and have introduced a mention of isolated storms
today given the large scale environment. I should stress that
coverage of thunderstorms today would be far less than what we've
experienced the past few days, should they manage to develop at
all.

Tonight and Saturday morning another complex of storms is expected
to develop across parts of Kansas and OK once again. However, the flow
aloft is expected to become more westerly as the upper ridge
begins to build across Texas. In addition, the most favorable low-
level flow and moisture transport is expected to be confined to
the Texas Panhandle and central OK. These factors would suggest that
convection will stay predominantly out of North Texas Saturday
morning and be confined to areas north of the Red River. Have left
low pops in the forecast for now but they may be able to be
removed if convection allowing models begin following the same
trends as the larger scale guidance.

By Sunday the upper ridge will begin redeveloping directly over
the Southern Plains. This will effectively bring an end to our
rain chances for several days along with a slight warming trend as
temperatures return to the upper 90s and near 100 degrees for
most of the upcoming week. Dewpoints should mix out into the low
to mid 60s for most areas which will keep heat index values under
105. By the end of the week, there is some indication in both the
European model (ecmwf) and GFS that an upper low will become cutoff from the
northern stream flow and will drift across south Texas Friday and
Saturday. This subtle weakness may be sufficient to allow low rain
chances to return to the forecast by late next week and next
weekend.

-Stalley

&&

Aviation...
/issued 1139 PM CDT Thursday Jul 28 2016/
earlier convection has ceased across north and central Texas. With
inhibition growing and nothing to force additional activity, a
quiet night looks to be on tap at the taf sites.

Based on the latest radar, satellite, and model trends, am
becoming increasingly concerned about the Prospect for convection
impacting the metroplex sites on Friday afternoon. A thunderstorm
complex is currently moving out of the Colorado Front Range and
towards the Oklahoma/Texas panhandles. While this activity should
weaken overnight, there are indications that outflow from this mesoscale convective system
may drive all the way to the Red River by Friday morning. In
addition, a subtle mid- level shortwave is also forecast to
impinge upon this region during the afternoon hours.

Given how moist the low-levels will remain, it seems plausible
inhibition will weaken sufficiently during the mid afternoon
hours to allow convection to fire in the vicinity of this outflow.
That said, the very low confidence in the final location of this
outflow and the large variation in high-resolution solutions
precludes the introduction of thunder at this time. Have added in
vcsh after 29/21z, however, and we will monitor for the potential
addition of thunderstorms in the vicinity in subsequent taf issuances.

Waco looks to remain far enough removed from the better moisture
to preclude any mention of precip in the 06z tafs.

Carlaw



&&

Preliminary point temps/pops...
Dallas-ft. Worth 97 79 98 79 99 / 10 10 10 5 10
Waco 98 77 98 77 99 / 10 5 5 5 5
Paris 95 75 96 76 96 / 20 20 20 10 10
Denton 95 76 97 76 98 / 10 10 10 5 5
McKinney 95 76 96 76 97 / 20 10 10 5 10
Dallas 97 79 98 79 98 / 10 10 10 5 10
Terrell 95 76 97 77 97 / 20 10 10 5 10
Corsicana 96 77 97 77 97 / 10 5 10 5 10
Temple 97 76 98 76 98 / 5 5 5 5 5
Mineral Wells 97 74 98 75 99 / 10 10 5 5 5

&&

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

$$

30/26

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