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Area forecast discussion 
National Weather Service Fort Worth Texas
1142 PM CDT Wednesday Sep 17 2014

Aviation...
persistent shower and thunderstorm activity has finally worked its
way east of the I-35 corridor just east of the kact area...and
should continue to move slowly off to the southeast through the
rest of the overnight hours. High moisture content from the
addition of moisture generated by the remnants of Odile off to our
west created localized flooding...fortunately not on any of the
area terminals. The potential for heavy rain will arise again
Friday afternoon as another slug of moisture spins off what
remains of Odile...and localized flooding may become an issue
during the late afternoon and evening hours Friday. At this
time...we will simply maintain a thunderstorms in the vicinity group at area taf sites with
the belief that thunderstorms with heavy rain will be too isolated
to be Worth mentioning at area taf sites. However... we will
include a thunderstorms in the vicinity group at all locations during the afternoon and
evening hours based solely on the amount of moisture and
instability present.




&&

Update...
convective activity continues across the southern counties of the
County Warning Area this evening and slow moving storms are producing heavy
rainfall. Localized areas of nuisance flooding or potentially
localized flash flooding may occur over the next few hours. The
activity is expected to weaken overnight in the absence of decent
lift and a weak low level jet. Adjusted probability of precipitation and temperatures overnight to
account for the latest trends.

More precipitation is expected to develop on Thursday and chances
for a heavy rain/flash flood potential appear to be increasing for
our southern and possibly southwestern areas. Today/S earlier
model runs indicated a rich moisture axis providing a focus for
convective development some where across our southern counties.
The boundary could be noted in the forecasted Theta-E fields and the
850-700 mb wind fields. Although the models varied on the location
of the this axis...they all had an axis of higher quantitative precipitation forecast amounts
developing some where in the central Texas area...generally around
and/or south of the Waco area. With high precipitable waters still in place
across the region...this raises some concern for a flash flood
threat across our southern counties on Thursday. Our neighbors to
the south already have flash/flood watches in place. We would
like to see the full 00z model suite before making any final
determinations of the need for and location of a watch. The 00z
NAM has now shifted the axis of precipitation across our southwest
and the 12z European model (ecmwf) appears to also support this. The most likely
time frame for heavy precipitation to occur is late Thursday morning
through the evening hours and we feel we have some time to see how
the overnight convection trends and also analyze the full 00z
model suite before making any final decisions on a Flash/Flood
Watch for tomorrow.

82/jld

&&

Previous discussion... /issued 355 PM CDT Wednesday Sep 17 2014/
scattered showers and thunderstorms have developed across the
region this afternoon ahead of a weak upper level shortwave. This
activity will tend to move east and southeast...and the most of
the activity is expected to shift to the south of I-20 later this
evening. Locally heavy rain and cloud to ground lightning will
accompany some of these storms. A few gusty winds may occur with
the storms before sunset.

We will remain in a moist atmosphere into the weekend as
southerly low level winds prevail while upper level moisture
continues to spread east across Texas. With weak disturbances
moving across the region...we will continue to see scattered
showers and thunderstorms. Some locally heavy rain will accompany
some of the storms late tonight through Thursday. At this
time...expect the more widespread heavy rain to be to the south of
the forecast area...thus will not be issuing a Flash Flood Watch
for our part of central Texas at this time. Rain chances should
shift more to the western part of the forecast area late Friday
into Friday night...but as the upper level remnants of Odile move
into the Central Plains...rain chances will return across all of
North Texas Saturday. As the Odile remnants move east...expect a
cold front to move down into late Sunday into early Monday. Rain
chances should come to an end across all but the southern zones
after Sunday night...with lingering chances into Monday south of a
Lampasas to Athens line. Rain chances will return by Wednesday as
another shortwave moves out into the plains.

58




&&



Preliminary point temps/pops...
Dallas-ft. Worth, Texas 74 89 73 90 73 / 20 40 20 20 10
Waco, Texas 72 86 71 89 70 / 60 70 20 30 10
Paris, Texas 71 88 68 89 69 / 20 30 10 10 10
Denton, Texas 72 89 70 90 70 / 20 30 20 20 10
McKinney, Texas 72 89 69 90 69 / 20 30 20 10 10
Dallas, Texas 76 89 73 90 73 / 20 40 20 20 10
Terrell, Texas 74 87 70 89 70 / 20 40 20 10 10
Corsicana, Texas 73 86 70 89 70 / 30 50 20 20 10
Temple, Texas 69 86 71 89 70 / 60 80 20 40 20
Mineral Wells, Texas 72 87 69 88 69 / 30 50 20 30 20

&&

Forward watches/warnings/advisories...
none.

&&

$$

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