538
FXUS64 KFWD 201039
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
539 AM CDT Sat Jul 20 2024

...New Aviation, Short Term...

.SHORT TERM... /NEW/
Update:
TX Panhandle and southwestern Oklahoma convection continues to
dissipate this morning, although a few isolated cells do remain
intact as far south as Wichita Falls as of 530 AM. We`ll maintain
low PoPs across the northwest this morning, with greater
convective chances still forecast this afternoon across
west/northwest portions of the forecast area. As alluded to in the
previous discussion, the greater rain chances will hold off until
Sunday when both an approaching frontal zone and mid-level
shortwave will offer greater ascent to support scattered
thunderstorm development.

-Stalley

Previous Discussion:
/Through Sunday/

Anomalously strong troughing and northerly flow aloft will be
maintained all weekend, with periodic thunderstorm chances and
near-normal temperatures. Upstream convective activity in the TX
Panhandle will encroach on North Texas after daybreak this
morning, but most or perhaps all of this convection will
dissipate prior to venturing into our CWA. It may, however, send
an outflow boundary into the Big Country and parts of western
North Texas which could serve as a focus for additional
thunderstorm development later this afternoon near and west of the
Highway 281 corridor. Have retained 20-30% PoPs in this area
through peak heating although coverage and placement of any
residual boundaries and resultant convection will remain quite
uncertain at a time range of more than a few hours. Otherwise, the
return to southeasterly surface flow will send both temperatures
and dewpoints a few degrees higher than yesterday.

An upstream frontal zone will make progress towards the forecast
area heading into Sunday, and this boundary will produce more
meaningful lift in conjunction with an approaching mid-level
vorticity maximum. This should result in scattered to numerous
thunderstorms across much of the CWA tomorrow afternoon. The
moderate instability and low shear environment typical of late
July will support an isolated microburst threat, but organized
severe thunderstorms are unlikely. Due to the presence of more
cloud cover and likely some convective outflow boundaries
tomorrow afternoon, highs may only reach the upper 80s to lower
90s for many locations.

-Stalley

&&

.LONG TERM... /Issued 403 AM CDT Sat Jul 20 2024/
/Monday Through Friday/

Texas will spend the upcoming week sandwiched between a strongly
amplified ridge in the West and a remarkably persistent Bermuda
high to the east. Early in the week, our northwest flow regime
will give way to troughing that will nose into the Lone Star
State from the northeast. Both of the aforementioned subtropical
ridges will strengthen through midweek, and while our mid-level
heights won`t significantly change, this will induce/enhance the
troughing overhead. A comparatively deepening saddle will maintain
minimal inhibition and daily rain chances. The persistent
convective activity should serve to reinforce the relative
depression aloft with some guidance suggesting a closed upper low
may develop by midweek. Unseasonably cloudy conditions will
prevail with below normal temperatures during what is
climatologically the hottest part of the year. The National Blend
of Models (NBM) has likely PoPs (at least 55 percent) within our
area each day from Monday through Thursday. This is far above
climatology, which is generally 15 to 25 percent across the region
in late July.

Aided by both a pronounced shortwave embedded in northerly flow
aloft and convective outflow at the surface, a cold front will
invade the region on Monday. While the bulk of the morning
convection may be coincident with the boundary, the activity will
steadily expand in areal coverage during the daylight hours as a
destabilizing uncapped boundary layer couples with increasing
forcing for ascent. Widespread showers and storms ahead of the
boundary will feed off of precipitable water values soaring above
2 inches. The precipitation efficiency, combined with the slow
motion of individual cells, will enhance rainfall amounts. Some
locations will experience multiple storms Monday afternoon, the
cumulative effect of which may result in flooding. The areas of
greatest concern will be across Central and East Texas, which will
have the longest duration south of the boundary. The rain and
extensive cloud cover will cap temperatures in the 80s, with the
NBM keeping parts of the Big Country in the 70s.

A similar but somewhat less rainy day will follow on Tuesday when
the frontal boundary will begin to lose its resolution. Sunshine
and fewer showers and storms will allow portions of North Texas to
reach or exceed 90F, a scenario that will repeat itself through
Friday. By midweek, the main heavy rain threat will shift into
South and Southeast Texas where the richest moisture influx will
be. However, further rounds of rainfall are expected Wednesday and
Thursday, particularly across Central and East Texas. Any
additional rainfall could initiate or reaggravate flooding
concerns. With persistent cloud cover and rainfall, some locations
across Central and East Texas may remain below 90F throughout the
upcoming workweek.

25

&&

.AVIATION... /NEW/
/12z TAFs/

VFR will prevail through the period with southeast winds of 10
kts or less. Upstream convection presently in the TX Panhandle and
western Oklahoma will steadily drift towards North Texas later
today, but will dissipate prior to reaching D10. Additional shower
and thunderstorm activity should materialize this evening and
overnight, possibly overspreading the North Texas airports around
or prior to 12z Sunday morning. VCSH will be introduced to the
extended DFW TAF with low confidence in timing. Precipitation
will also be accompanied by an increase in cigs between 5-10 kft.

-Stalley

&&


.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    94  76  91  74  85 /   5  20  50  40  60
Waco                95  74  94  73  87 /   0  10  40  30  70
Paris               90  71  89  70  84 /   0  10  20  40  60
Denton              95  72  92  71  84 /  10  30  40  40  50
McKinney            94  73  91  72  86 /   0  20  40  40  60
Dallas              95  76  92  75  86 /   0  20  50  40  60
Terrell             92  72  92  72  85 /   0  10  30  40  70
Corsicana           94  74  94  74  87 /   0  10  30  30  70
Temple              96  73  94  72  88 /   0   5  30  20  70
Mineral Wells       97  71  91  70  84 /  20  30  40  40  60

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$