Forecast Discussion for Dallas/Ft. Worth, Texas

409
FXUS64 KFWD 231934
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
234 PM CDT Wed Oct 23 2019


.SHORT TERM...
/Tonight through Friday afternoon/

Low level warm air advection will increase tonight ahead of a low
pressure system and associated cold front, resulting in a warmer
and breezy night with lows from the middle 50s to the lower 60s.
The cold front will move into the northwest zones late tonight,
bringing a broken line of showers and thunderstorms. These storms
will become more organized after sunrise Thursday as the upper
trough deepens over Southern Colorado/Northern New Mexico and the
cold front moves south into more abundant moisture. The primary
hazard associated with these storms will be from locally heavy
rainfall and lighting. However, there may be enough instability
and shear across the region to support a few robust updrafts that
may produce some marginally severe hail, primarily across Central
Texas Thursday afternoon and evening. Although some locally heavy
rainfall will be possible, widespread flooding is not anticipated
since the front will be progressive and deep moisture will be
absent. Average rainfall amounts through Thursday evening will be
between 1 and 2 inches, but some amounts in excess of 2 inches
will be possible, especially across the northeast zones.

Models are coming more in line regarding the movement of the
upper low with a general track across the Texas Panhandle and
Southern Oklahoma Thursday night through Friday. This will push
most of the rain/storms to East and Northeast Texas, but it will
remain cool and breezy with highs Friday struggling to get out of
the 50s. There may be some lingering light rain across the Central
and Western counties Friday morning, but rain and clouds should
gradually clear from west to east through the day with increasing
subsidence behind the departing system.

79

&&
.LONG TERM...
/Friday Night Through Mid Next Week/

A deep and narrow upper level trough with an associated upper
level low is expected to be centered over North Texas Friday
evening. A vigorous shortwave trough and associated tropopause
fold should be wrapping around the south side of the upper low,
allowing the system to rapidly fill and eject northeast overnight
Friday into Saturday morning. Some lingering light rain and low
level cloudiness associated with wrap around moisture in the
vicinity of the surface low (centered over the lower Mississippi
Valley) should be ongoing through the night across the areas east
of I-35 and north of I-20, with all precip coming to and end by
daybreak Saturday. A robust dry conveyor belt and surface high
should be moving into the area Saturday allowing dry air entrainment
and surface heating to erode any lingering low level cloudiness
by the early afternoon. This will set the scene for great weather
Saturday and Sunday with crisp mornings both days with lows in the
40s and highs in the 60s and 70s, respectively.

Continuing into next week both the deterministic and ensemble
guidance members are struggling to get a handle on the large-scale
pattern, which will greatly affect the local sensible weather.
What we are confident of ATTM is a deep low developing near the
Aleutian Islands which in-turn should develop a blocking ridge
across the North Pacific. This ridge will induce the deepening of
a trough across the Intermountain West late this weekend/early
next week. What we are uncertain of ATTM is how the trough will
evolve over the CONUS. It will either deepen into SoCal and move
through North/Central Texas mid to late next week or progressively
move through the North/Central Texas in the early parts of next
week. The current forecast package is using a blended approach,
leaning heavily on the national blended guidance to avoid falling
into the trap of biting on a favored solution too soon.

With that being said, confidence is high of the trough moving
through at some point next week, and once the trough does move
into the Central CONUS, it will be accompanied by a strong bout of
high pressure and CP air moving into our area. An earlier trough
passage would likely mean a dry front since return flow ahead of
the system will be limited. A later in the week passage would
favor a wetter system with stronger jet dynamics and baroclinicity,
thus a higher potential for severe weather associated with the
attendant cold front. Bottom line...A strong cold front is expected
to move through the area at some point next week, but we will
need to keep an eye on what happens out west over the next few
days to gain confidence on the timing and evolution of the system.

Bonnette

&&

$$


.AVIATION... /Issued 1218 PM CDT Wed Oct 23 2019/
/18Z TAFs/
No major aviation weather concerns through this evening
with a mostly clear sky and a breezy south wind between 12 and 17
knots along with some gusts near 27 knots.

The cold front will move across the Red River in the pre-dawn
hours Thursday with storms likely moving into the the Bowie
cornerpost between 11Z and 13Z. The storms should become more
organized along the cold front as they approach the Metroplex
airports late Thursday morning. For now we will include VCTS in
the extended portion of the DFW TAF beginning at 19Z, but a
prevailing group for thunder will most likely be introduced in the
00Z TAF issuance. MVFR ceilings will arrive ahead of the front
just after sunrise at all TAF sites and remain in place through
the afternoon. Some brief IFR ceilings and visibility restrictions
will be likely in any thunderstorms.

The northerly wind shift associated with the frontal passage will
likely occur between 18Z and 19Z Thursday at the Metroplex TAF
sites and a few hours later in Waco.

79

&&

.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    60  69  49  59  45 /   5  80  80  50  30
Waco                60  75  49  61  44 /   0  60  80  40  20
Paris               53  66  49  56  45 /   5  50  70  50  40
Denton              61  64  46  59  42 /  10  90  80  40  30
McKinney            59  67  48  59  44 /   5  80  80  50  30
Dallas              61  70  50  60  46 /   5  80  80  50  30
Terrell             58  72  50  61  45 /   0  60  70  50  30
Corsicana           57  76  50  60  45 /   0  60  70  40  30
Temple              62  78  49  61  43 /   0  60  80  40  20
Mineral Wells       60  63  42  56  39 /  10  90  70  40  30

&&

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

$$

79/06

NWS FWD Office Area Forecast Discussion