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Area forecast discussion 
National Weather Service Fort Worth Texas
539 am CST Monday Nov 30 2015


For the 12z tafs...timing the improvement of flight categories is
the primary short term forecast concern. The potential for fog
Tuesday morning is the other aviation weather concern.

To start off the forecast...kfws radar was picking up on some very
light radar returns moving east over Tarrant County as of 510 am/
1110z. These returns were consistent with a reduction in
visibility at upstream ASOS sites...and likely represent a fine
mist or drizzle falling from the low IFR cloud deck. Went ahead
and started off the tafs with IFR visibility due to this area of
very light precipitation moving over the area. Expect that this
light drizzle will move east of area taf sites after 14z...but
will amend based on short term radar and surface observation

After the early morning drizzle passes...expect VFR visibilities
for the remainder of the day today. Cloud heights are expected to
slowly climb throughout the day as subsidence from aloft reduces
the thickness of the clouds from the top down today. This process
will allow less filtering of sunlight as we move through the
day...causing clouds to climb to MVFR levels just before noon. A
middle-level front is expected to move east over the area this
afternoon scouring out most remaining cloud cover as it passes by.

Early Tuesday morning...a ridge of high pressure will build over
North Texas. Winds are expected to become light and variable just
before 12z. With only some cirrus expected...the combination of
light winds and mostly clear skies may be sufficient for
radiational fog to develop. Only went with MVFR visibilities for
now as the late onset of the surface high combined with some
cirrus present to radiate heat back to the surface limit an
otherwise ideal fog environment.



Previous discussion... /issued 319 am CST Monday Nov 30 2015/
radar imagery across the region this morning is very
quiet...especially in comparison to the past 96 hours during which
several rounds of rain resulted in rainfall totals over 10 inches
in some areas of North Texas. The Holiday weekend rain event is
over but there are still low rain chances for parts of the region
today and tomorrow.

It is damp and chilly this morning with fog and drizzle occurring
across much of the region. Temperatures are in the upper 30s to
middle 40s with light winds. The fog and drizzle will likely remain
through middle morning as weak isentropic lift continues in the
295-300k layer. During the late afternoon elevated
front in the 850-700 mb layer will move east across the region
bringing dry subsident air to north and central Texas.

The large upper level low that had been stalled to our northwest
is finally moving east across The Rockies this morning. The
eastward progression of this system will help push the elevated
front through our area. Ahead of this area of lift is
noted on infrared and water vapor satellite imagery. On infrared
imagery this area of lift is being depicted by a swath of cooling
cloud tops moving across central Oklahoma and northwest Texas. Per
the latest upper air analysis...this area of lift appears to be
coincident with the elevated front. As this region of lift and the
elevated front move across north and central Texas today...enough
lift may occur for some scattered light showers or light rain to
develop. Will keep 20 probability of precipitation region-wide this morning and then
shift 20-30 probability of precipitation this afternoon and tonight across central Texas
and our eastern counties. Rainfall rates and accumulations will be
less than 1/10th of an inch. Will continue with low probability of precipitation along and
south of a Palestine to Lampasas line on Tuesday as there may be a
weak area of lift remaining near our southern border with a weak
shortwave moving over central Texas. The remainder of the week
will be dry with some rain possibly returning early next week.

Temperatures the next several days will reach the 50s each day
with overnight lows mainly in the 30s and lower 40s. Near
freezing temperatures can be expected in our northwestern counties
tonight and Tuesday night. A reinforcing shot of cool air will
arrive on Wednesday as another upper level trough moves across the
Southern Plains. Daytime temperatures will not change much with
this front but overnight lows will be cooler Wednesday night
under the influence of drier air...clear skies and light winds.
Much of north and central Texas is expected to be near freezing in
the lower 30s Wednesday night/Thursday morning.



Preliminary point temps/pops...
Dallas-ft. Worth, Texas 53 38 55 38 55 / 20 5 5 5 5
Waco, Texas 55 40 56 40 55 / 20 10 10 10 10
Paris, Texas 51 37 53 36 52 / 30 10 10 10 5
Denton, Texas 51 35 54 35 53 / 20 5 5 5 5
McKinney, Texas 51 37 53 36 53 / 20 5 5 5 5
Dallas, Texas 53 39 55 39 55 / 20 5 10 10 5
Terrell, Texas 53 39 56 38 54 / 20 10 10 10 5
Corsicana, Texas 53 41 56 42 55 / 30 20 10 10 10
Temple, Texas 55 42 56 41 56 / 20 30 20 20 10
Mineral Wells, Texas 53 34 55 35 54 / 20 5 5 5 5


Forward watches/warnings/advisories...


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