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000 
FXUS64 KFWD 180812
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
212 AM CST Mon Nov 18 2019


.SHORT TERM...
/Today and Tonight/

The northerly winds that were in place yesterday afternoon were
short lived as winds have started to swing around from the 
northwest, and eventually from the southwest this afternoon. It is
these southwesterly downsloping winds that will allow for 
temperature to climb into the 70s today. Given guidance tends to 
underdo the warming effects of the downsloping terrain, have sided
with the warmer guidance. 

A weak shortwave moving along the northwesterly flow aloft will
allow for some high clouds through much the morning, especially 
north of I-20. These high clouds should continue moving to the
southeast and exit the region by the afternoon. 

Lows tonight will be in the mid 40s to around 50 degrees as winds
become light out of the southwest. 

Hernandez

&&

.LONG TERM...
/Tuesday onward/

The theme of the forecast for the upcoming week remains largely
unchanged with this forecast package. Monday and Tuesday look to
be fairly quiet in terms of weather, with things becoming more
active for the back half of the week. A few strong to severe
thunderstorms as well as locally heavy rainfall may be possible on
Thursday.

The main driver of the active weather later in the week will be a
strong upper-level trough that is forecast to dig into the western
United States by mid-week. The timing differences that we have
been seeing between the GFS and ECMWF appear to be closing a bit,
though the ECMWF does remain a bit slower than the GFS (with the
GFS known to have a fast bias, and the ECMWF known to have a 
slow, albeit smaller bias). Ahead of the main longwave trough, a
shortwave trough will propagate across the Southern Plains,
resulting in surface cyclogenesis across the Central Plains. This
will in turn bring gusty southerly winds to our forecast area.
While this would normally lead to some concerns for an elevated 
fire danger, humidity will be on the increase, tempering this 
threat.

As lift associated with the shortwave trough increases, isolated
to widely scattered showers and thunderstorms are forecast to
develop across West Texas, and track northeast across western
North Texas and into Oklahoma. Our highest PoPs on Wednesday
afternoon and Wednesday night will be along the Red River, north
and northwest of the Dallas/Fort Worth Metropolitan Area.

On Thursday, the surface low will lift north into the Midwest,
pushing a cold front into North Texas. More widespread shower and
thunderstorm development can be expected Thursday, with Likely
PoPs now indicated across much of our county warning area during
this timeframe. The deterministic GFS also shows CAPE values of
around 500 J/kg combined with strong (60+ knot) deep-layer wind
shear. Instability is probably a little on the low side for
significant severe weather, but with this strong of shear and
low-level forcing, a few strong thunderstorms capable of gusty
winds and small hail may not be out of the question. Additionally,
the fact that these showers and thunderstorms will be widespread
and last much of the day, widespread rainfall accumulations of
0.50 to 1.50 inches look likely. The highest rainfall totals will
be in our northeastern counties, with rainfall accumulations
decreasing the farther southwest one goes. Locally higher amounts
in excess of three inches will be possible in some locations,
which could lead to localized flooding of flood-prone areas.

Showers and thunderstorms will continue behind the front on
Thursday night and into Friday, but coverage and intensity should
decrease through the day Friday. The majority of the showers and
thunderstorms should end by Friday evening, but some lighter rain
may still linger, especially east of Interstate 35. By and large
though, Friday evening should be characterized by cool and cloudy
conditions, with just isolated to scattered light rain showers.

The weekend and Monday look cool but dry, with rain and
thunderstorm chances looking to return by next Tuesday as another
upper-level trough swings into the western United States.

37

&&


.AVIATION... /Issued 1109 PM CST Sun Nov 17 2019/
/06 UTC TAF Cycle/

Concerns---None. VFR with light west/southwest winds. 

VFR will prevail at all TAFs over the next 30 hours. SKC will 
slowly give way to cirrus that should invade from the west through
the TAF period. Northwesterly breezes during the pre-dawn hours 
will become more westerly through the day with speeds AOB 10 
knots. The light nature of the wind will mean no crosswind issues 
and a good chance that area terminals can return to a south flow 
takeoff/landing config. Winds toward the end of the day may become
more southwesterly, but I'll defer to future shifts to handle 
these largely inconsequential changes. 

Bain

&&

.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    71  45  76  57  74 /   0   0   0   0  50 
Waco                71  44  77  56  76 /   0   0   0   0  30 
Paris               65  43  73  52  71 /   0   0   0   0  30 
Denton              70  44  75  56  72 /   0   0   0   0  50 
McKinney            69  44  75  56  73 /   0   0   0   0  40 
Dallas              71  46  77  57  74 /   0   0   0   0  40 
Terrell             70  44  76  55  74 /   0   0   0   0  30 
Corsicana           68  44  75  56  75 /   0   0   0   0  30 
Temple              71  44  76  57  76 /   0   0   0   0  20 
Mineral Wells       71  42  76  56  73 /   0   0   0   5  50 

&&

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

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