Forecast Discussion for Dallas/Ft. Worth, Texas

FXUS64 KFWD 111033

Area Forecast Discussion
National Weather Service Fort Worth TX
533 AM CDT Tue Aug 11 2020

The outflow boundary from last night has stalled and washed out,
and south winds can be expected area-wide for the rest of the day.
Recent high resolution CAMs have become slightly more aggressive
with afternoon thunderstorm development across the northeast, and
POPs have been raised slightly in that area. A grass fire danger
statement was issued early this morning for areas west of I-35;
otherwise nothing else of significance to add to the previous
short-term discussion.


Previous Discussion:
/Through Wednesday/

A shortwave trough ignited an area of showers and thunderstorms
across the Southern Plains Monday afternoon, and this activity
continues to push east-southeast across Oklahoma and Northwest
Texas tonight. Activity has been mostly undercut by an outflow
boundary, which extended from Oklahoma City to Vernon to near
Lubbock around midnight. This boundary will produce a brief shift
to northwest winds across the northwest zones during the
overnight hours. It should eventually be overcome by the strong
southerly low level flow and will likely stall prior to daybreak

Isolated thunderstorm development in the vicinity of the boundary
is not out of the question, and have added slight chance POPs for
areas roughly along and north of a Graham to Paris line for the
rest of the night. Subsidence associated with a strong ridge
should suppress additional development farther south. One issue
that will need to be monitored is an ongoing wildfire along the
Jack/Palo Pinto County line, which would be affected by the wind
shift if the outflow reaches far enough south, so will be keeping
a close eye on that for the rest of the night.

Precipitation along/north of the Red River will abate Tuesday
morning as the low level jet mixes out. However, additional
showers and storms will be possible later in the day through
Tuesday evening across the northeast counties as the shortwave
drops southeast through the Arklatex region. Chance to slight
chance POPs will hence be in place during the afternoon and
evening hours for areas northeast of the DFW Metroplex. Severe
weather is unlikely, though 3000 J/KG of MUCAPE will open the door
for a few strong storms with gusty winds.

Hot and breezy weather will persist for the rest of the forecast
area through Wednesday. Elevated fire weather conditions will be
in place each afternoon west of I-35 where minimum RH values dip
below 30 percent. Heat index readings will start to climb to or
above 105, especially starting Wednesday. Will likely hold off on
a Heat Advisory today, but may need to look at issuing one
starting Wednesday.



.LONG TERM... /Issued 234 AM CDT Tue Aug 11 2020/
/Wednesday Night through Monday/

Our summertime subtropical ridge will begin to expand back
eastward late Wednesday through the end of the week resulting in a
hot and dry end of the week. Temperatures will run about 3-5
degrees above normal for this time of year with highs near 100
areawide each afternoon. A modest southerly breeze will continue
and will provide some relief to those outdoors. Afternoon mixing
of boundary layer moisture is resulting in dewpoints in the
low/mid 60s and while we`ll likely see a slight uptick through the
end of the week, the combination of a persistent breeze and
sufficient mixing will preclude the necessity of a heat advisory
at this time. Our eastern counties will be closest to advisory
criteria through the middle and latter part of the week with heat
indices in the 103-106 degree range each afternoon.

By the weekend, deeper troughing will become more pronounced over
the eastern half of the CONUS. This will allow for ridge
amplification across the western U.S. with the center of the ridge
shifting back to the west and placing most of the Southern Plains
back in a northerly flow aloft. While it`ll still be warm,
it`s likely that we`ll shave a few degrees off of afternoon highs
Sunday into Monday. The extended guidance actually shows a front
sliding southward into the region on Monday and this looks like
our best chance for any precipitation in the next week. We`ve kept
PoPs at 20% for now and will continue to monitor.

Otherwise, it`ll remain hot and dry through the extended. We`ve
seen a recent uptick in grass fires across the region, especially
west of I-35 and this trend will likely continue with afternoon
humidity dropping to around 30%, temperatures near 100, and a
persistent southerly wind.



Scattered low clouds can be seen on morning fog satellite imagery
across Central Texas, an will likely affect KACT for a few hours.
Farther north, thunderstorms are still looking to affect northeast
portions of DFW TRACON this afternoon/evening, but will likely
remain northeast of Metroplex airports. Otherwise, VFR and south
winds will continue.


Previous Discussion:
/06Z TAFs/

VFR and continued breezy conditions with southerly winds can be
expected area-wide for the next 36 hours. Will keep an eye on
ceilings across Central Texas, where an MVFR deck may get close
to the Waco area around daybreak Tuesday. For now, will keep a
SCT layer at KACT for Tuesday morning, with higher sky coverage
likely staying southeast of the airport.

TS will be possible for northeast portions of DFW TRACON Tuesday
afternoon. At this time, it appears storms will remain northeast
of the DFW Metroplex airports.



Dallas-Ft. Worth   101  79 100  81  99 /   5   5   0   0   0
Waco               101  78 102  78 101 /   0   0   0   0   0
Paris               96  73  97  76  98 /  40  20   5   0   5
Denton              99  77  99  80 100 /  10  10   0   0   0
McKinney           100  76 100  80  99 /  10  10   0   0   0
Dallas             100  80 100  81 100 /   5  10   0   0   0
Terrell            100  77  99  77  99 /   5  10   0   0   0
Corsicana          100  77  97  78  99 /   5   5   0   0   0
Temple             100  77 102  76 101 /   0   0   0   0   0
Mineral Wells      100  77 101  77 102 /   5   0   0   0   0





NWS FWD Office Area Forecast Discussion