NWS Area Forecast Discussion


000
FXUS64 KFWD 230234
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
934 PM CDT Wed Mar 22 2017

.UPDATE...
The only significant change to the previous forecast is to
increase wind speeds on Thursday. As the lee side trough deepens,
the pressure gradient will tighten across North and Central
Texas. This pressure gradient should support southerly winds of 15
to 25 mph by late morning across most of the forecast area. Some
gusts of 30 to 35 mph will be possible along and west of the I-35
corridor. A Wind Advisory may be necessary for parts of North and
Central Texas Thursday. Wind speeds will probably not immediately
decrease as sunset approaches, so have also increased wind speeds
for Thursday night.

58

&&

.AVIATION...
/ISSUED 704 PM CDT Wed Mar 22 2017/
Afternoon VFR cloud cover will continue to decrease, eventually
giving way to SKC conditions later this evening as surface winds
additionally slacken a bit. Nocturnal stratus will make a
resurgence tonight on a strengthening 35-45 kt low-level jet.
While some guidance suggests the potential for cigs dropping to
IFR overnight, forecast and observed temperature-dewpoint spreads
upstream across the Upper Texas Coast, combined with a well mixed
atmosphere in the lowest 2 kft suggest that MVFR should be more
prevalent. MVFR cigs should quickly scatter Thursday morning as
drier air moves in and strong daytime mixing occurs. At the same
time, mixing will result in the development of strong and gusty
south-southeast winds. Some occasional gusts in excess of 30 kts
appear possible, especially Thursday afternoon. These gusty winds
will continue well into the evening.

Another surge of low stratus is anticipated Thursday night, but
just outside the DFW extended TAF. A stout capping inversion is
expected to inhibit any precipitation chances through the valid
TAF period.

Carlaw


&&



.PREV DISCUSSION... /ISSUED 316 PM CDT Wed Mar 22 2017/
An upper ridge currently parked over the Southern Plains will
shift east tonight through Friday as a West Coast upper trough
heads east. Return flow will be on the increase tonight and
tomorrow as lee-side troughing intensifies and the pressure
gradient narrows. A 40 KT low level jet will develop in advance of
the system this evening after winds decouple. These strong 925 MB
winds will mix to the surface mid to late morning Thursday,
creating warm and breezy conditions. At this time, it appears that
relative humidity values will remain too high to create
significant wildfire concerns.

Thursday night: forcing for ascent should become strong enough to
generate scattered showers and storms over West TX and the Texas
Panhandle. Convection will likely initiate along a dry line, which
will be followed closely by a Pacific front. Storms will spread
east into western counties of North Texas as the Pacific front
overtakes the dry line overnight, likely developing into a QLCS as
the system moves into the I-35 corridor Friday morning. Early on,
there could be a few strong to possibly severe storms with a low-
end damaging wind threat. A better chance for severe storms (with
both a damaging wind and large hail threat) will occur east of
I-35 where the atmosphere will have time to destabilize late
Friday morning and Friday afternoon. Rain chances will end from
west to east Friday afternoon, with just about all precipitation
exiting the easternmost locales by sunset.

Cooler and drier conditions are expected Saturday following the
passage of the cold front. This will be short-lived, however, as
a second upper trough will quickly induce return flow late
Saturday into Sunday. There is quite a bit of energy with this
system, but the lack of appreciable moisture may limit convective
development for much of the area. The most likely scenario is that
there will be scattered storms Sunday afternoon and evening
initially developing near the Red River where the coldest air
aloft and steepest lapse rates will be. This activity would
develop farther south with time while spreading east, so the
highest POPs will be across the northeastern counties, with
generally lower POPs the farther south you go. Shear and
instability will be sufficient for a few strong to possibly
severe storms, with large hail and damaging winds equal threats.

The upper level pattern looks to remain active and fairly
progressive as we move through next week. All models are
advertising a deep upper low right over the middle of the
country a week from now, with subtle differences in timing and
intensity. The time of year alone is enough justification to keep
in mind that there will at least be some possibility of severe
weather, with better details becoming realized with time.

30



&&


.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    63  85  65  82  57 /   0   5  40  70   5
Waco                64  83  65  81  55 /   5   5  30  70   5
Paris               57  82  60  72  55 /   5  10  10  70  20
Denton              62  84  63  81  54 /   0   5  40  60   5
McKinney            61  83  62  75  55 /   0   5  30  70   5
Dallas              63  85  65  79  57 /   0   5  40  70   5
Terrell             61  84  63  74  57 /   5   5  20  70  10
Corsicana           62  85  63  75  58 /   5   5  20  70  20
Temple              63  84  63  81  56 /   5   5  30  70   5
Mineral Wells       61  85  60  83  53 /   0   5  50  40   5

&&

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

$$

90/58

NWS FWD Office Area Forecast Discussion