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Area forecast discussion...updated 
National Weather Service Fort Worth Texas
610 PM CST Friday Feb 27 2015

/00z tafs/

Concerns will continue to be transitioning winter precipitation type
overnight from -sn to -fzdz...possible brief -pl as moisture
column encounters top-down drying by midnight/after. In
addition...cig/vsby cats will also be challenging and will be
related to both actual precipitation and moisture on the ground and wind

We will likely see prevailing IFR Cat through much of the
night at all tafs...though brief MVFR ceilings could occur through
02z...with some less than 1sm fog/br from predawn Saturday through
middle morning may occur at dfw metropolitan locales. Transition from -sn
to more -fzdz is expected to occur between 05z-08z per model
soundings and MOS guidance for the dfw metropolitan...however am
concerned with areas to the west of dfw/kmwl for instance/ already
indicated some -fzdz/-fzra. Will continue to monitor with NE flow
5-10 kts prevailing.

At Waco...we expect temperatures to continue to fall below freezing with
patchy -fzdz or possible spotty -fzra by daybreak Saturday as
weak isentropic processes occur over the top of the shallower
Arctic airmass down that way. They too could see brief LIFR
conditions from daybreak to middle morning with some fog.

Afterward...mostly beyond 18z is very uncertain on how the
overrunning pattern sets up and how surface temperatures react. For
now...have continued previous trends of IFR with precipitation
transition to -ra.



a band of moderate to heavy snow continues to develop between
Decatur...Denton and the Red River late this afternoon in an area
of enhanced instability. This area has already received up to 5
inches of snow and has the potential to receive appreciable snow
amounts over the next several hours with snow totals up to 8
inches possible. With this in mind...we will issue a small Winter
Storm Warning to account for the higher snow totals. The warning
will be for wise...Denton...Cooke and Grayson and will be valid
until 6 PM Saturday. No other changes are necessary at this time.



Previous discussion... /issued 404 PM CST Friday Feb 27 2015/

..Winter Weather Advisory will remain for light snow...
Transitioning to freezing drizzle/light freezing rain overnight
into Saturday...

..southern zones...Added to a Winter Weather Advisory from 6 PM
tonight until noon Saturday for a mix of light snow and light
freezing drizzle....

The area of light to occasionally moderate snow currently east of
a line from about Bowie to Granbury will continue moving
east/northeast through late afternoon with the departing short
wave. This should produce an additional one half to one inch of
snow...especially between Decatur...Fort Worth and the Red River with
a few isolated higher amounts. Behind this main line...some light
snow or flurries will linger through the evening but should add
little to the current snow accumulations. When all is said and
done...snow totals should average between 2 and 5 inches from the
Interstate 20 corridor northward with between one half inch and 2
inches in all but the southeast third of the region.

Central Texas radars currently show an increasing feed of low
level moisture in the form of mainly light rain and drizzle across
the Texas Hill country. This moisture will continue to advance
northward into North Texas overnight while surface temperatures either
remain or fall below freezing. This will result in mainly light
freezing drizzle across the entire region. The only exception will
be the southeast zones which are currently above freezing and
should not fall below freezing until later this evening or
overnight. We have decided to add these southern zones to a Winter
Weather Advisory tonight into Saturday morning...mainly for
freezing drizzle...possibly mixed with light snow during the
evening. Since large scale lift will be very weak...we do not
anticipate freezing rain and significant ice accumulations.
However...even an additional light glaze from freezing drizzle
will result in or add to ongoing travel problems.

The warm layer will continue to increase on Saturday and
precipitation should transition to light rain from south to north
as surface temperatures warm above freezing. We are a bit
concerned that freezing temperatures will linger through middle
afternoon in many locations due to the current snow coverage in
the north and the expected cloud cover. Therefore...we will carry
the Winter Weather Advisory until 6 PM Saturday for all but the
southeast zones. In the southeast zones we will run the advisory
until noon Saturday.

Surface temperatures should slowly warm Saturday night through
Sunday morning as southeast surface winds return. Other than some
weak perturbations in west to southwest flow aloft...we do not
anticipate any major source of large scale lift so will only keep
some chance probability of precipitation for light rain. Some patchy fog is also possible
Saturday night through Sunday.

A cold front will approach the Red River on Sunday and may sneak
into the northern zones as per the NAM and European model (ecmwf) solutions. The
front may provide additional lift for some light rain as well as
bring cooler temperatures. Have decided to go with a blend of the
solutions regarding highs on Sunday so will lower the northern
zones highs to the middle and upper 40s with mainly 50s and 60s

North Texas will stay in a very unsettled weather pattern through
the middle of the week as an upper low moves east from the Pacific
and merges with a northern branch upper trough to form a deep long
wave trough. The response across North Texas ahead of this
developing system will be and increase in low level moisture
Monday through Tuesday with increasing instability. It look likes
the best chance for thunderstorms will be Tuesday afternoon/Tuesday

Storms should end from north to south Tuesday night with the
passage of another strong cold front. It appears that another
chance for winter precipitation will be possible behind the front on
Wednesday. Right now sleet appears to be the primary precipitation type.
Any Post frontal precipitation should end Wednesday night with dry
northwest flow expected Thursday through Friday.



Preliminary point temps/pops...
Dallas-ft. Worth, Texas 27 35 35 49 42 / 60 60 40 40 50
Waco, Texas 28 38 38 60 47 / 40 60 40 40 40
Paris, Texas 25 33 33 46 37 / 60 60 40 40 50
Denton, Texas 24 34 34 49 37 / 60 60 40 40 50
McKinney, Texas 25 35 35 50 40 / 60 60 40 40 50
Dallas, Texas 28 38 38 54 44 / 50 60 40 40 50
Terrell, Texas 30 37 37 53 41 / 40 60 40 40 50
Corsicana, Texas 28 39 39 59 49 / 40 60 40 40 50
Temple, Texas 29 41 41 63 51 / 50 60 40 40 40
Mineral Wells, Texas 25 33 33 52 39 / 60 60 40 30 50


Forward watches/warnings/advisories...
Winter Weather Advisory until 6 PM CST Saturday for txz091-094-

Winter Weather Advisory until noon CST Saturday for txz135-

Winter Storm Warning until 6 PM CST Saturday for txz092-093-102-




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