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Area forecast discussion 
National Weather Service Fort Worth Texas
625 am CDT Friday Jul 3 2015

Aviation...
MVFR ceilings possible early this morning but these should lift to VFR
by or after mid-morning. Otherwise the main concern in the
forecast is the potential for convection. Thunderstorms are
theoretically possible at any point during the next 18 hours...but
will try to restrict the mention of thunder to the most likely
timeframe which is during the afternoon and early evening hours.
There is enough moisture and elevated instability this morning for
at least some scattered showers...but expect the thunderstorms to
remain just north and northeast of the metroplex. Will show vcsh
in tafs for now...but this will require close monitoring.
Additional scattered showers/storms will develop this afternoon
generally in a band along and north of the I-20 corridor. These
storms will produce variable and gusty winds in their vicinity
which may interrupt the prevailing S/SW flow even if storms do not
occur on station. Will show variable winds tempo group.

For Waco...probability of convection looks too low to mention in
taf at this time. MVFR ceilings will prevail through middle morning with
VFR conditions expected for the afternoon and evening. Another
round of MVFR stratus is possible late tonight.

Tr.92

&&



Previous discussion... /issued 309 am CDT Friday Jul 3 2015/
North Texas is currently wedged between a broad upper trough
across the eastern half of the Continental U.S. And an upper ridge across
the west. This pattern is providing northwest flow aloft...which
means that any weather system which affects North Texas will
likely approach from the north or northwest. A shortwave now
extending from the Midwest to the Southern Plains is dropping
southeast while generating scattered showers and thunderstorms
across Oklahoma and the Texas Panhandle. Activity has weakened
overnight with the loss of surface heating...but isolated storms
should still continue due to good moisture and modest instability
remaining in place. Some of this activity should begin to affect
counties adjacent to the Red River early this morning.

Better opportunities for thunderstorms will occur late this morning
and this afternoon as low level instability increases with
boundary layer heating. The most recent hi-res guidance suggests
convective development generally along and north of the Interstate
20 corridor. Outflow from overnight convection will provide
additional focus for development...and the location of the highest
coverage of showers and storms will depend on where mesoscale
boundaries lie. At this time...the highest probability of precipitation will continue
across the northern-most counties where some likely probability of precipitation will be
in place. Slow southward storm motion will bring storms farther
south later in the day...with probability of precipitation tapering to 20s along a
Comanche-Palestine line.

Weak shear will limit severe potential...but cape around 1500
j/kg should be sufficient for a few strong storms with gusty
winds. Slow storm motion combined with precipitable waters around 2 inches will
allow storms to produce brief heavy rain...and localized flooding
cannot be ruled out. Activity will diminish this evening as
surface heating wanes...but a few isolated storms could continue
into the late evening hours.

The focus for convection will shift southeast along with the
shortwave trough on Saturday...with the best chances of
thunderstorms occurring east of the Interstate 35 corridor. Storms
will be scattered in nature with the best opportunity to see a
storm in the late afternoon and early evening hours. The majority
of the activity will be on the decrease by the time most July 4th
fireworks commence.

By Sunday...the main shortwave will have shifted southeast to the
middle Texas coast and lower MS valley...keeping chances for
precipitation mainly to our east. However...we will maintain weak
north flow aloft through middle week...which will allow for some low-
end probability of precipitation mainly across the northern most counties. For the second
half of next week...upper ridging strengthens overhead...which
should lead to generally hot and dry conditions in the extended
portion of the forecast.

30

&&




Preliminary point temps/pops...
Dallas-ft. Worth, Texas 92 76 92 76 92 / 40 30 30 20 10
Waco, Texas 93 74 92 74 92 / 20 5 10 10 10
Paris, Texas 86 72 87 73 88 / 60 60 50 30 40
Denton, Texas 91 73 91 74 91 / 50 40 30 20 10
McKinney, Texas 91 74 91 75 90 / 50 40 30 20 20
Dallas, Texas 93 76 92 77 93 / 40 30 30 20 10
Terrell, Texas 91 74 90 74 90 / 40 30 30 20 20
Corsicana, Texas 92 74 91 74 91 / 20 10 20 20 10
Temple, Texas 92 72 92 73 91 / 10 5 10 10 10
Mineral Wells, Texas 91 72 92 73 92 / 40 20 20 10 10

&&

Forward watches/warnings/advisories...
none.

&&

$$

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