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Area forecast discussion...updated
National Weather Service Fort Worth Texas
1103 PM CST Mon Nov 18 2019

/06 UTC taf cycle/

Concerns---none major. Very low non-convective low level wind shear potential
during pre-dawn hours Tuesday.

VFR will continue through the entire taf cycle. With surface
winds diminishing and winds aloft at around 20 knots, there could
be some minor non-convective low level wind shear. At this time, however, it
appears that the greatest shear magnitude will be just outside of
the 2000 foot layer necessary for inclusion and i'll abstain from
the mention of low level wind shear in the tafs.

Otherwise, southerly winds will return during the day on Tuesday
with speeds gradually increasing in the mid to late the afternoon.
Speeds should remain at or below 12 knots. High cirrus will invade from
the west and southwest. This cirrus will thicken later in the taf
period (hours 18-24), but VFR will prevail.



Long term... /issued 347 PM CST Mon Nov 18 2019/
/Tuesday night through this weekend/

Strong southerly flow will start to take hold of the region Tuesday
night as the dominating surface high pressure center shifts east
and leeside cyclogenesis over SW Colorado increases. The enhanced
return flow will allow a blanket of stratus to develop across
central Texas Tuesday night and make its way through North Texas
before daybreak Wednesday. The increased cloud cover combined
with strong warm/moist advection will keep Wednesday morning's
lows in the mid 50s across the area.

A shortwave trough will be ejecting out of the desert SW Continental U.S.
And moving over the Central Plains Wednesday. This will eject the
leeside surface low out of SW Colorado with the low moving into
the upper Mississippi Valley by Wednesday night. In the upper
levels, a pool of abnormally high precipitable water air will be streaming
over the Sierra Madre Mountains and moving into north and central
Texas. The current naefs and European model (ecmwf) eps mean guidance is indicating
precipitable water and integrated moisture flux values approaching and exceeding,
respectively, the 99.5th percentile by Wednesday evening. Normally,
this could indicate the potential for an areal flooding or flash
flooding threat, however, the lack of well defined surface forcing
and little to no instability across the region should mitigate any
potential flood threats. Attm, we expect scattered rain showers
to develop Wednesday afternoon west of I-35 in the open warm sector
along a weak confluent area in the low levels. The showers should
become more widespread overnight north of I-20 as the low level jet increases
in magnitude, however only brief rumbles of thunder are possible
as a capping inversion helps keep the instability at-Bay. Precip
amounts should be on the light side (less than 0.25") due to the
lack of convection.

The attendant cold front of the aforementioned surface low will
be making its way south Wednesday night and eventually stall out
along or just north of the Red River. This will keep thursday's
low temperatures relatively warm in the low to mid 60s, about 20
degrees above climatology. The front should remain stalled out
across the Red River Thursday with off/on rain continuing in the
vicinity of the front. Across the remainder of north and central
Texas, isolated to widely scattered light rain showers will
continue through the day with daytime highs tapping out in the mid
70s. There is very small potential for a weak dryline to develop
across Big Country Thursday. If the instability increases ahead of
the boundary, a few isolated strong thunderstorms are possible
Thursday afternoon/evening. The likelihood of this is low attm,
but something to watch for.

Another shortwave trough will be quick on the heels of the
previous and begin ejecting into the Southern Plains Thursday
night into Friday. This will help drive the stalled out frontal
boundary south Thursday night into Friday. The forced ascent
along the leading edge of the boundary will be the focus for
additional precip development across all of north and central
Texas, with the heaviest precip expected to remain north of I-20
and east of I-35. Instability should once again be lacking ahead
of the front, limiting the convective threat. Scattered Post-frontal
rain should continue through the early part of the day Friday as
weak shortwave pertubations continue streaming ahead of the 500 mb/700 mb
baroclinic zones. These zones should move through Friday night,
bringing an end to the precip by Saturday morning. All in all,
areas north of I-20 and east of I-35 can expect between 0.5-0.75"
of rain with this system. Areas west of I-35 and south of I-20 can
expect less than 0.25" of rain.

The passage of the cold front will mean yet another storybook
weekend is expected across north and central Texas with partly
cloudy skies and temperatures slightly below climatology Saturday
and Sunday.



Short term... /issued 1141 am CST Mon Nov 18 2019/
/through tomorrow/

Pleasant and tranquil weather will continue through tomorrow with
above normal temperatures. Winds have veered to the west/southwest
ahead of an ill-defined surface trough axis which will become
draped through southern Oklahoma tonight. This feature will have
little/no effect on sensible weather other than to continue
shifting the already light winds in place. Dewpoints will begin
increasing a bit overnight, which will hold Tuesday morning's lows
a few degrees higher, mainly in the 40s to near 50 degrees. The
warming trend will continue tomorrow, with highs in the 70s
beneath sunny skies.



Preliminary point temps/pops...
Dallas-ft. Worth 45 75 53 75 60 / 0 0 0 30 40
Waco 40 77 52 77 60 / 0 0 0 20 30
Paris 45 72 51 72 61 / 0 0 0 20 60
Denton 42 74 55 73 62 / 0 0 0 40 40
McKinney 45 75 54 74 63 / 0 0 0 30 50
Dallas 50 77 56 75 64 / 0 0 0 30 40
Terrell 44 77 54 76 63 / 0 0 0 20 40
Corsicana 44 77 55 76 63 / 0 0 0 20 30
Temple 43 78 56 77 63 / 0 0 0 20 30
Mineral Wells 45 77 53 72 59 / 0 0 0 50 30


Forward watches/warnings/advisories...

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