Area Forecast Discussion
Issued by NWS Dallas/Fort Worth, TX
FXUS64 KFWD 251755
Area Forecast Discussion
National Weather Service Fort Worth TX
1255 PM CDT THU AUG 25 2016
18 UTC TAF Cycle.
Concerns---Low MVFR ceiling potential Friday morning. Convective
potential Friday afternoon.
For the Metroplex TAF sites---Generally VFR conditions are
expected through the entire TAF cycle, including the 30-hr DFW
TAF. Moisture will continue to slide westward around the periphery
of the SE U.S. high over the next 24 to 30 hours. While low level
moisture will increase, it appears that the weak wind field will
keep the better threat for MVFR ceilings to the south and east of
the DFW terminals. The potential for short-lived MVFR stratus will
be monitored, however, in subsequent TAFs. The increase in
moisture, combined with less subsident air across North TX should
yield a chance for convection. The TTU WRF remains the most
aggressive model with regards to widespread showers and likely TS.
Most other hi-resolution model guidance, however, remains
slightly more conservative, so for now will go with a VCSH for the
afternoon time period.
For the Waco TAF site---There will be a slightly better threat for
MVFR ceilings, but the weak wind field as portrayed by most
guidance suggests that MVFR stratus will remain south of the TAF
site. Similar to the Metroplex TAF sites, overall coverage of
convection remains too uncertain to prevail VCTS/TS, so for now
will include a mention of VCSH for Friday afternoon.
.PREV DISCUSSION... /ISSUED 306 AM CDT THU AUG 25 2016/
One more relatively quiet day across North and Central Texas, as
the Southeast CONUS upper ridge continues to retract back east-
northeast toward the U.S. East Coast. As this transition occurs,
a subtle shortwave aloft will rotate around the western periphery
of the upper ridge this afternoon across far East Texas. We have
maintained 20-30 percent chances for our far E/SE counties through
sunset this evening. With richer PWAT values between 1.5-2 inches
creeping westward, the atmosphere will become more moist adiabatic
with brief heavy downpours, localized gusty winds, and lightning
strikes as the main hazards with any stronger cores. Temperatures
will remain very warm today with highs in the lower 90s south to
the middle 90s north. Overnight conditions will remain muggy with
lows in the 70s areawide.
As the upper high center continues shifting northeast over the
Mid-Atlantic region Friday into the weekend, a deep tropical flux
of moisture will shift west over the area. Meanwhile, periodic
waves of shortwave energy will rotate northwest and north across
the eastern half of Texas. This continuation of weak forcing
interacting with strong late August heating will result in
periodic, mainly diurnal chances for convection containing brief
heavy downpours. Have not introduced higher chances through the
weekend due to the absence of any surface fronts or boundaries
that would help focus higher concentrations of showers and storms.
Higher rain chances will likely remain confined across South and
Southeast Texas during this period, as a slow-moving easterly wave
transits westward across that part of the state.
The higher moisture content, clouds, and scattered convection
should help keep high temperatures in check and generally around
or below seasonal normals in the low 90s. A few areas across
especially the southeast half of the CWA may only see highs in the
middle to upper 80s, depending on where convection becomes more
concentrated during the daytime hours.
The center of the eastern CONUS upper high will shift slightly
southwestward and extend from from the Carolinas to the Deep
South early next week. This modest southwestward shift of the
high will result in better, low diurnal convective chances
occurring over Central Texas and across some of our western areas
Monday through Wednesday. Similar to the weekend, with mesoscale
surface boundaries lacking and forcing aloft being fairly subtle,
will only introduce 20-40 percent probabilities through the
period, with the bulk of activity occurring during the afternoon
and early evening hours.
Regarding the Tropics, models keep shifting the forecast for the
disturbance over Hispaniola back to the east as compared from 24
hours ago. This disturbance will eventually be named Hermine once
it reaches tropical storm status. The general consensus of the
Euro/GFS are close to TPC progs of bringing this tropical
disturbance into the Bahamas this weekend, then across southern
Florida on Monday, before it heads northward along the west coast
of Florida into the Florida Panhandle by Wednesday due to the
effects of a trough moving into the Ohio/Tennessee Valleys. That
being said, we expect no effects from any tropical disturbances
across the western Gulf of Mexico the next 10 days.
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 95 77 91 76 92 / 5 5 50 20 20
Waco 92 74 91 73 91 / 5 5 50 20 20
Paris 93 75 89 73 91 / 20 10 60 30 30
Denton 94 74 90 73 92 / 0 5 40 20 20
McKinney 93 75 90 73 91 / 10 5 50 20 20
Dallas 95 78 91 76 92 / 5 5 50 20 20
Terrell 93 75 90 74 91 / 20 10 50 20 30
Corsicana 92 76 90 74 91 / 20 10 50 20 30
Temple 91 73 91 72 90 / 10 5 40 20 20
Mineral Wells 94 73 91 71 93 / 0 5 30 10 20