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Area forecast discussion...corrected 
National Weather Service Fort Worth Texas
403 am CST Friday Dec 26 2014


There are several different weather elements affecting the
forecast in the next 7-8 days but no significant impacts are
expected across north and/or central Texas. Of note...all mention
of winter precipitation next week has been removed and the
reasoning for this will be discussed below.

This morning...a strong upper level low was moving across northern
Arizona with the base of the associated upper trough digging into
northern Mexico. Southerly winds continued across the region this
morning but a cold front was making its way across Kansas and
through the Texas Panhandle. Low level clouds are spreading across
the region this morning and will slowly erode from west to east
throughout the day. Temperatures today will warm into the upper
50s and 60s with warmer afternoon highs across the west and
southwest where the cloud cover will thin this afternoon...and
cooler afternoon highs in the east where mostly cloudy skies will
persist. Isentropic lift will increase across the region today
ahead of the approaching cold front. Low level moisture will be
highest over the eastern counties where we keep a 20-30 percent
chance for rain/showers today. Rainfall amounts today will be
light and generally no more than 1/10th of an inch is expected.

The cold front arrives tonight while the upper level trough still
remains west of the region. It should be entering our northwestern
counties just before or around midnight and then pushing out of
our southeastern counties around middle morning Saturday. Areas of fog
will be possible ahead of the front but widespread dense fog is
not expected. There are continued chances for rain ahead of and
with the front overnight tonight. The best rain chances will be
primarily east of Interstate 35 where chances increase to 40-50
percent after midnight. Forecast soundings indicate some elevated
Cape May be present tonight so included a mention of isolated
thunderstorms across all but the northwestern counties. Some of
the hi-res guidance indicates a narrow band of showers/storms may
occur along the front as it moves through the region.

As the front exits the region Saturday morning...most of the rain
will end. the approaching upper level trough
continues to spread lift across the region...there could be some
elevated showers/light rain. Have left low probability of precipitation in the forecast
across much of the forecast area for the remainder of Saturday for
this reason. Temperatures trends on Saturday are complicated as
most of the area will experience nearly steady and/or falling
temperatures through the day...but our northwestern counties will see a
slight warming in the afternoon. As a surface high settles in
Saturday night...overnight lows will fall into the upper 20s in
the northwest to upper 30s in the southeast. The upper level
trough will swing through the Southern Plains on Sunday and while
most of the models keep the area dry on Sunday...the NAM develops
more light precipitation across our southern counties. Will keep
the forecast dry for now but continue to monitor Sunday.

On the heels of sundays upper level trough will be another
developing upper level trough along the West Coast. This second
trough actually originates south of Alaska where it is currently
located. As it dives will facilitate cold Arctic air
moving out of Canada and down the plains to Texas. The Arctic
front is still expected to arrive on Tuesday with drastically
colder temperatures Tuesday through Thursday.

Previous forecasts mentioned low chances for winter precipitation
sometime during the Tuesday through Thursday/Friday time frame.
This was due to the interaction of the Arctic air with the upper
level trough in developing precipitation across the region. The
models have continued to trend towards a slower timing and track
of the upper level low and they do not bring the upper level low
into the Southern Plains until Friday now. With a lack of large
scale lift across the region and weak ridging ahead of the upper
level low...have removed the mention of precipitation and winter
precipitation from the forecast Tuesday through Wednesday. Some of
the models are still developing light quantitative precipitation forecast across our western
counties on Tuesday along an elevated front...and will continue
to monitor this situation...but a lack of larger scale lift tends
to result in a drier forecast.

Precipitation chances increase on Thursday and Friday as the upper
level low moves into the Southern Plains...but by then the surface
high will have already moved east and south winds will act to
modify and warm the surface temperatures. Thus...all liquid
precipitation is expected to fall Thursday and Friday and removed
the mention of winter precipitation from these days as well.



/issued 1118 PM CST Thursday Dec 25 2014/
concerns...MVFR to IFR ceilings and MVFR visible.

Regional 88d VAD wind profiles are already showing a strong low level jet
extending from south Texas northward into North Texas. High end
stratus have formed around ksat and areas southward and northward
into the kact/kcrs area. The stratus will continue to advect
northward overnight and expect them to lower into the 1-2 kft
range after 06z. Once low-end MVFR ceilings have developed...we expect
them to be around for some time. Have decided to include a tempo
group for IFR ceilings /ovc006/ and 5sm br 13-16z for both kact and
across the metroplex. The ceilings may lift above 2000 feet late Friday
afternoon...but then returning to ovc015 for early Friday evening.
Ceilings should fall further late Friday evening with conditions at
4sm br bkn007 through late Friday night. Winds will remain
southerly 10-17kts tonight and 8-15 kts on Friday/Friday evening.

The kdfw extended now includes a cold front arriving 08-09z...late
Friday night. Winds of 32016kt and MVFR ceilings /ovc012/ should prevail
afterward through daybreak Saturday. 75


Preliminary point temps/pops...
Dallas-ft. Worth, Texas 64 45 46 32 50 / 20 30 20 10 10
Waco, Texas 66 49 49 33 53 / 10 30 20 10 10
Paris, Texas 60 50 50 32 49 / 20 50 20 10 10
Denton, Texas 63 41 45 29 50 / 10 30 20 10 10
McKinney, Texas 62 46 46 31 50 / 20 40 20 10 10
Dallas, Texas 64 47 47 33 51 / 20 40 20 10 10
Terrell, Texas 62 52 52 33 50 / 20 50 20 10 10
Corsicana, Texas 65 54 54 35 51 / 20 50 30 10 10
Temple, Texas 70 52 52 34 53 / 10 30 20 10 10
Mineral Wells, Texas 67 38 43 28 51 / 10 20 20 10 10


Forward watches/warnings/advisories...




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