Scientific Forecaster Discussion
fxus64 kfwd 231718
Area forecast discussion
National Weather Service Fort Worth Texas
1118 am CST Tue Jan 23 2018
VFR conditions with only some scattered cirrus is expected
through 00z Thursday. A surface ridge that extended across West
Texas at taf issuance time will slowly move eastward tonight and
Wednesday. As it does, north winds around 10 knots at midday
Tuesday will decrease to around 5 knots after 02z and then become
light and variable by 12z Wednesday. As the surface ridge moves to
our east, winds will come around to the south-southeast around 5
knots by 17z Wednesday.
Short term... /issued 322 am CST Tue Jan 23 2018/
/today and tonight/
Rain-free conditions will continue through the short term forecast
period with tranquil conditions anticipated.
Northwesterly winds this morning will slowly become more northerly
through the day as surface high pressure settles in across the
region. Winds will be much lighter today compared to Monday as the
surface pressure gradient will remain loose. Moreover, wind speeds
in the 15 to 25 mph range atop the planetary boundary layer will mean that mechanical
mixing's contribution to the surface wind magnitude will remain on
the low-side. As a result, we don't anticipate a critical fire
weather threat, though fire starts will be possible due to the dry
conditions. The threat for rapidly spreading grassfires will be
low as most areas should see peak surface winds under 15 mph. The
dry air in place will allow temperatures to climb above normal
values with most areas topping out in the 50s to mid 60s. There
will be an increase in mid and upper level cloud cover ahead of
an upper level trough across the Gulf of California. If this
cirrus is thicker than anticipated, it's possible that conditions
may be a little cooler than advertised.
For tonight, low temperatures should near or even fall below
seasonal values. Surface high pressure will settle in across
western zones. With mostly clear skies, light winds and a dry
airmass in place, temperatures should fall quickly after sunset.
Temperatures out west and across low-lying areas will likely fall
into the low to mid 20s. Elsewhere, temperatures in the 30s should
Long term... /issued 322 am CST Tue Jan 23 2018/
/Wednesday through Monday/
North and central Texas will remain under the influence of an
upper ridge on Wednesday with a mostly sunny sky and high
temperatures generally in the lower 60s. Since the Gulf will
remain closed off, temperatures will fall quickly after sunset
and cool into the 30s Wednesday night.
Low level warm air advection will slowly increase on Thursday as a
shortwave moves onshore in the west and a surface Lee trough
develops across the Central High plains. This will keep
temperatures slightly above seasonal normals with highs in the
The Lee trough will deepen Thursday night which will continue to
draw low level moisture northward. Large scale lift will also
increase Thursday night as the shortwave translates across the
region. The combination of lift and moisture will bring a chance
of showers to the entire region, but since the moisture will
remain relatively shallow, the chances for appreciable rainfall
will be low.
The shortwave will exit the region before sunrise Friday which
will bring a temporary end to the rain chances. However, another
fast moving shortwave will follow on its heels Friday and bring
increasing rain chances along with some thunderstorms Friday
afternoon and Friday night. We will maintain the highest pops
generally east of I-35 where the deepest moisture will reside.
The shortwave trough axis will move east across the state
Saturday and allow a cold front to move through the region. The
front will supply additional lift for scattered showers and
thunderstorms. However, instability and shear will be limited so
we don't anticipate much of a severe weather threat at this time.
Precipitation chances will end from northwest to southeast
Saturday afternoon once dry and subsident air moves in behind the
departing shortwave and cold front.
Saturday night and Sunday will be dry and a bit cooler with lows
mainly in the 30s and highs from the middle 50s to the lower 60s.
A bit of a warmup will start on Monday once an upper ridge begins
to build in from the west, but low level moisture will not return
until later in the week.
Preliminary point temps/pops...
Dallas-ft. Worth 61 35 61 36 64 / 0 0 0 0 0
Waco 63 27 62 32 63 / 0 0 0 0 5
Paris 57 30 58 34 61 / 0 0 0 0 0
Denton 60 27 60 33 63 / 0 0 0 0 0
McKinney 58 32 60 33 63 / 0 0 0 0 0
Dallas 60 36 61 37 63 / 0 0 0 0 0
Terrell 59 32 60 33 62 / 0 0 0 0 0
Corsicana 61 35 61 35 62 / 0 0 0 0 5
Temple 64 31 62 33 62 / 0 0 0 0 5
Mineral Wells 61 26 62 31 65 / 0 0 0 0 0