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Area forecast discussion...updated 
National Weather Service Fort Worth Texas
559 PM CDT sun Jul 24 2016

concerns...potential for scattered thunderstorms Monday

Mostly VFR conditions are expected at the taf sites through the
taf period. The isolated showers and thunderstorms east of a kdua-
kcrs line as of 23z are expected to dissipate toward sunset and
will not affect the taf sites. An upper level ridge to the
northwest has kept most of the region under strong subsidence
during the last several days. As this ridge shifts slowly west and
an upper low moves westward into the region, we will have
scattered thunderstorms mainly in the afternoon and evening hours
starting Monday. Thus have placed thunderstorms in the vicinity in the metroplex and Waco
taf sites between 18z and 23z and vcsh 23z-02z. Expect south to
southeast winds 5 to 10 knots this evening to become easterly by
18z Monday.



Previous discussion... /issued 315 PM CDT sun Jul 24 2016/
an upper level ridge centered over New Mexico will continue to
shift slowly west while a mid/upper level trough works its way in
from the east. Convection associated with the trough has been
persistent over Louisiana and East Texas the past several days
and has been developing a little farther west each day. A distinct
shortwave rotating around the northern edge of the trough is
likely responsible for the latest round of convection now
lighting up the radar from the arklatex region to central and
southern Louisiana. Most of these showers and storms are diurnally
driven and should linger through sunset before dissipating later
in the evening.

Later tonight, a deep and at least partially tropical airmass
will spread in from the east. Pwats are expected to climb to over
2 inches across the eastern counties overnight. Recent model
guidance has begun to indicate the possibility of nocturnal
thunderstorms developing within this moist airmass as the lead
shortwave moves overhead, and we have introduced pops along and
east of a Sherman-Palestine line during the overnight hours.

This moist airmass will continue to spread in from the east during
the day Monday, with 2 inch precipitable water values reaching west of the I-35
corridor, and some of the eastern counties exceeding 2.25 inches
by afternoon. Ongoing activity across the east in the morning
should increase in coverage while spreading west, as the
atmosphere further destabilizes with surface heating. Locally
heavy rainfall may be something to consider, particularly across
the southeast where the highest moisture resides. Fortunately, it
appears that the scattered nature of the activity combined with at
least some modest southwest storm motion should limit any flood
threat to isolated heavier cells.

Strong downburst winds could become an issue during the late
afternoon and early evening hours, but the threat may be
minimized by the high moisture environment. Severe weather
appears unlikely at this time, though some minor wind damage from
outflow cannot be entirely ruled out.

Rain chances will continue Tuesday and Wednesday as the upper
trough continues to move slowly west across Texas. The best rain
chances should occur across the southern-most counties where 2+
precipitable water air will remain.

Another shortwave trough is progged to drop southeast across the
plains Wednesday night and Thursday in the northwest flow around
the eastern edge of the high pressure ridge. This feature will
briefly sync up with the now weakening easterly wave over Texas
and bring another chance of showers and storms across the
forecast area. These two systems will part ways on Friday, but
the end result will be a lingering weak trough overhead Friday
into next weekend. This will ensure at least some slight chance
pops as we move through the end of the month.



Preliminary point temps/pops...
Dallas-ft. Worth 81 96 78 96 78 / 10 50 20 30 10
Waco 78 96 75 95 75 / 10 50 30 40 20
Paris 76 93 75 95 75 / 30 50 20 20 10
Denton 78 95 76 94 76 / 10 40 20 30 10
McKinney 78 94 76 94 76 / 20 50 20 20 10
Dallas 80 95 79 95 79 / 10 50 20 30 10
Terrell 77 93 76 94 76 / 20 50 20 30 10
Corsicana 78 94 76 94 75 / 20 60 20 30 20
Temple 77 96 75 94 75 / 10 40 30 50 20
Mineral Wells 75 96 74 95 75 / 5 30 20 30 10


Forward watches/warnings/advisories...



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