Area Forecast Discussion
Issued by NWS Dallas/Fort Worth, TX
FXUS64 KFWD 170532
Area Forecast Discussion
National Weather Service Fort Worth TX
1132 PM CST Thu Feb 16 2017
VFR is expected through 04z Saturday. As an upper level low
currently over northern Mexico moves northeast, we will have an
increase in mid-level moisture across North and Central Texas.
There will be a slight chance of showers and maybe some elevated
isolated thunderstorms Friday east of a K0F2-KLZZ line. The
chances at the TAF sites are way too low to mention in the TAFs at
this time. South winds 8 to 10 knots at TAF issuance time will
increase to around 15 knots by 15z and winds will back around to
the southeast at around 10 knots after 00z Saturday. The southerly
low level flow will tap some gulf moisture and MVFR stratus will
spread into the TAF sites between 04z and 06z Saturday.
The previous forecast is in good shape. Two main changes made.
First: We broke down the weather forecast for Friday keeping the
20 percent chance of showers/isolated thunderstorms only across
the southeast in the morning and leaving it across most areas east
of a Bowie to Lampasas line during the afternoon. This is mainly
based on the HRRR and TTU WRF. Second: Have increased the wind
speeds a little on Saturday based on forecast pressure gradient
shown by the NAM.
.PREV DISCUSSION... /ISSUED 404 PM CST Thu Feb 16 2017/
Mostly sunny skies prevail across North Texas this afternoon with
temperatures running about 5 degrees above normal and generally
light southerly winds. The nice weather will continue for the next
couple of days before the approach of a strong storm system late
this weekend that will bring another round of showers and
thunderstorms to the area.
For the remainder of today and tonight...light southerly winds
will prevail under partly cloudy skies. Water vapor imagery shows
a fairly large upper low spinning over north-central Mexico that
will head in our direction overnight and this will spread some mid
level moisture into the region after dark. This should result in
an increase in cloud cover by morning. Temperatures tonight will
be about 10 degrees warmer than last night.
For Friday...as the core of the upper trough gets closer to North
Texas...lapse rates will steepen. The bulk of the mid level
moisture that gets transported north tonight will begin to spread
off to the northeast by mid morning. However...forecast soundings
indicate that even shallow moisture above 700 mb in the presence
of these steep lapse rates could result in some high based
convection. Despite mostly sunny skies...by late afternoon as
stronger forcing for ascent spreads across the area...we could see
some isolated high based showers or possibly a thunderstorm. Will
have a 20 PoP to account for this. The main threat with any
convection tomorrow would be strong winds and small hail.
Saturday should be mostly quiet across the region with mid level
ridging passing overhead. Some low precip chances may linger
across the far northeast counties where weak ascent persists in
the presence of low level moisture. Otherwise it will be partly
cloudy with temperatures warming into the upper 70s and lower 80s.
As we head into Sunday...a much strong upper trough will dig well
into Mexico. Increasing deep layer southerly flow will become
established across the Southern Plains by late in the day. This
will help rapidly transport Gulf moisture northward and will allow
a fairly narrow axis of modest surface based instability to
develop from the Coastal Bend northward into North Texas (mainly
west of I-35). As stronger forcing for ascent spreads in from the
west during the late afternoon...scattered showers and
thunderstorms are expected to develop. Lapse rates are initially
fairly steep with strong deep layer shear profiles...although
unidirectional. This initial activity Sunday afternoon could pose
a low end severe hail risk.
Of more concern Sunday night will be an increasing threat for
training precipitation echoes...especially across the southern
half of the CWA. Widespread showers and thunderstorms are expected
to overspread North Texas and deep southerly flow will generally
suggest that these will move quickly from south to north. The
whole area of precipitation will gradually move east overnight
Sunday night into Monday morning. Precipitable water values
forecast to be around 1.6" in our area will be near record highs.
As of now...it looks like the strongest forcing will pass to the
south of us...which would likely mean the heaviest rain would stay
to the southeast of our area...closer to the coast.
Nonetheless...with recent rainfall over the last few days...any
additional training heavy rains could produce some localized flash
flooding. All of this activity should move to the east during the
day on Monday.
Weak shortwave ridging in the wake of this system should result in
mostly dry conditions through mid week with temperatures in the
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 46 71 55 78 55 / 0 20 5 5 0
Waco 45 71 53 81 57 / 0 20 5 0 5
Paris 42 68 52 69 52 / 0 20 10 20 0
Denton 45 71 52 76 52 / 0 20 5 5 0
McKinney 44 69 53 73 52 / 0 20 5 10 0
Dallas 48 71 56 76 57 / 0 20 5 5 0
Terrell 45 69 54 76 55 / 0 20 5 10 0
Corsicana 46 71 55 76 58 / 0 20 5 5 5
Temple 46 71 54 81 57 / 5 20 5 0 10
Mineral Wells 43 72 47 78 51 / 0 10 0 0 5