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Area forecast discussion
National Weather Service Fort Worth Texas
720 PM CDT Sat Jun 24 2017

00 UTC taf cycle

Concerns---timing of MVFR cigs and onset of rain showers at Waco
taf site. Low MVFR cig/vis potential at metroplex taf sites.

Metroplex taf sites---current tafs indicate VFR through the
entire period, but there is a low potential for MVFR cigs/visby.
2330 UTC visible imagery at this hour indicates clearing skies
atop north to northeasterly surface winds. These winds are
resulting in weak dry air advection which should result help in
the demise of the diurnal cumulus. After sunset lingering mid-level
clouds around fl150-fl180 will prevail. There may be a few bouts
of very light rain that precipitate from these mid-level clouds,
but this potential is far too low to include in the taf and should
pose little to no significant impact to the aerodromes. With a
northeasterly wind, drier air should spill southward, mitigating
the appreciable threat for MVFR cigs and as a result, i've
cautiously removed the mention of the MVFR stratus. We will keep
an eye on this, however, as any backing of the winds could draw
just enough moisture to warrant re- introduction of MVFR back into
the metroplex tafs. The clearing skies, however, may support the
development of br--- perhaps resulting in MVFR visby restrictions.
The northeasterly winds of 5 to 10 knots, however, should limit
this potential and for now, i'll simply advertise VFR br. Any
noteworthy restrictions to visby or cigs should be limited to the
early morning hours. Diurnal VFR cumulus should re- develop on Sunday
with some convection to the west. At this time, it appears
unlikely that widespread showers will impact the terminals
directly, but there could be some minor disruptions to western
arrival/departure gates.

Waco taf site---the potential for MVFR cigs appears slightly
higher across central Texas on Sunday morning as east moist transport
continues. As a result, I have retained the mention of this
phenomenon. Any reduced MVFR cigs should lift through the
afternoon hours. Have also continued with a mention of vcsh across
central Texas as the moist airmass should promote the development of
this activity. The potential for thunder looks low given the small
amount of instability, so I will omit this from the taf at this



Short term... /issued 251 PM CDT Sat Jun 24 2017/
/thru Monday night/

Just about the entire County Warning Area continues to remain cloudy, cool, and
stabilized from overnight/morning showers and storms the past 24
hours. Just about everybody saw some sort of measurable rainfall
the past 24 hours. Cloud tops have warmed significantly since
midday with even breaks in the cloud cover across the north. A few
spits of sprinkles or light rain continued across central Texas,
but nothing of significance. That said, some areas from near
Dallas southwest toward Stephenville, Comanche, south toward
Hamilton received 2-4 inches with isolated amounts to 5 inches, so
definitely some very beneficial rainfall from this early Summer
mesoscale convective system. The very moist and cool boundary layer should saturate once
again overnight with quite a bit of stratus around for Sunday
morning. Can't rule out a little spotty light fog this evening
through through the pre-dawn hours where partly cloudy skies
exist, but we do not expect any widespread, significant fog
tonight. Otherwise, a few showers may persist across central Texas
tonight where some residual weak, isentropic ascent will
continue. We do not expect any convective activity tonight to be
anything like last night.

The upper ridge will remain to the west and we should see east-
northeast winds and pleasant temperatures Sunday in the lower-mid
80s, once stratus slowly mixes out early in the afternoon. A
subtle shortwave disturbance will arrive in diffluent and weak
northwest flow aloft during prime heating and could spark off a
few showers and isolated thunderstorms mainly south of I-20 and
across central Texas. Some shower activity will maintain through
nightfall across our southwest counties Sunday night, but most of
the area should remain dry.

The upper ridge will remain relatively weak and mainly off to our
southwest moving into Monday, with ripples of mid level energy
sparking off isolated to scattered showers and thunderstorms
South-West of dfw. Lapse rates are not impressive and we do not
expect any severe weather, though an isolated strong late day
storm cannot be ruled out. A few showers will linger across the
Colorado River valley through nightfall Monday evening, with
relatively dry conditions the remainder of Monday night. Multi-
layer partly-mostly cloud cover should limit widespread fog
development both Sunday and Monday nights, though some patchy
thicker fog can't be ruled out wherever breaks in the cloud cover
can occur each night.


Long term... /issued 251 PM CDT Sat Jun 24 2017/
/Tuesday thru next weekend/

Low, mainly diurnal convective chances will hold on across central
Texas Tuesday-Wednesday, however we expect coverage to be more
limited, as the southwest Continental U.S. Upper high, though not overly
strong, continues to expand east across the western Gulf of
Mexico. In addition, Lee cyclogenesis across eastern Colorado
should bring a return of breezy south-southeast winds and humidity
from the Gulf of Mexico, as Summer makes a fervent return. Highs
will rebound into the lower-mid 90s, especially along and west of
I-35. Combined with the increasing Gulf humidity, heat indices may
become an issue once again. A weakness in the upper high will
continue to be evident across far east and southeast Texas through
the end of the week, thus low diurnal convective chances will
occur each afternoon Thursday and Friday across the southeast
third of the County Warning Area. It will continue to remain breezy, as a more
active storm track within the polar westerlies remains well north
of the area.

A slightly more amplified northern branch trough will move out
over the plains Friday night and Saturday, with a surface cold
front stalling northwest of our area across the Oklahoma/Texas
panhandles into Arkansas and Missouri. Signs still point to a
weakening mesoscale convective system late Friday night into Saturday morning entering
areas north of the I-20 corridor. However, at this point, we'll
continue to only advertise low convective chances until higher
certainty comes with future forecasts. It will remain seasonably
hot and steamy next weekend with mostly dry conditions, as the
main jet streams remains well north of the area.



Preliminary point temps/pops...
Dallas-ft. Worth 71 84 70 87 71 / 5 10 10 10 5
Waco 72 86 70 87 70 / 30 40 20 20 10
Paris 66 85 65 86 65 / 5 0 10 10 5
Denton 69 84 67 86 68 / 5 10 10 10 5
McKinney 69 85 67 86 68 / 5 5 10 10 5
Dallas 71 85 70 87 71 / 5 10 10 10 5
Terrell 69 85 68 87 69 / 10 10 10 10 5
Corsicana 71 85 69 86 70 / 30 30 10 20 10
Temple 71 85 69 86 69 / 40 40 30 30 20
Mineral Wells 67 83 67 85 68 / 10 20 10 20 10


Forward watches/warnings/advisories...

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