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Area forecast discussion 
National Weather Service Fort Worth Texas
1040 am CDT Sat Apr 25 2015

back edge of cirrus cloud shield is receding from southeast
counties...and have updated to remove probability of precipitation and decrease
cloudiness in those areas. Elsewhere...current temperature/wind
forecast still looks good. Per the 12z forward sounding...shallow
morning inversion over North Texas should rapidly erode through
the late morning. With gusty westerly downslope winds
increasing...afternoon temperatures should have no problem climbing into
the middle/upper 80s by 3-4 PM.



/issued 531 am CDT Sat Apr 25 2015/
VFR will prevail through the period with just some high clouds.
Light south/southwest winds early this morning will become
west/southwest after sunrise. Speeds will increase during the
day...rising to around 15kt this afternoon. Speeds should remain
low enough to where Crosswinds will not impact rates on north-S
runways. Winds will diminish after sunset to 5 to 10 knots. Tr.92


the upper low responsible for Friday/S severe weather continues to slowly
inch towards the east across the central and Southern Plains. After
a very brief respite from the recent active weather on
Saturday...attention will then turn to the latter half of the
weekend and early portion of next week...where a couple of severe
weather episodes will be possible. Thereafter...conditions are
expected to become more tranquil after the passage of a cold
front around mid-week.


Short term...
drier air should continue to work it/S way into the region as the
dryline/Pacific front slowly push eastward as the upper low lifts
out into the Ohio/Tennessee River valleys. For this morning...will maintain
slight chance probability of precipitation across our far southeastern zones where the drier
air has yet to reach. In addition...radar trends across The Hill
Country suggests that a few showers and storms may drift into our
far southeastern zones. West to west-southwest winds should support
some of the warmest temperatures we have seen so far this year due
to the compressional warming associated with the downslope regime.
While Waco/S record high temperature of 94 degrees set back in
1996 will likely remain out of reach. The record high temperature
of 91 set back in 1925 at dfw will be threatened. For now...have
kept temperatures in the upper 80s across much of north/central
Texas with a few 90s out across western zones where the relatively
drier air will allow for slightly greater warming. Skies should
be clear as drier air aloft overspreads the area...and today should
be a nice day for outdoor festivities.

Heading into Sunday morning...low level warm/moist advection
should be confined to far southeastern zones as the upper low that
is now across the Pacific northwest moves closer to the region.
Temperatures will vary region wide tonight as areas along and
northwest of a Comanche to dfw to Paris line should remain
slightly cooler with the drier air...compared to areas across the
southeast where low level warm/moist advection /courtesy of a
south to southeast wind/ will begin and should result in a slight
increase in cloud cover to limit nocturnal cooling and perhaps a
few areas of patchy shallow ground fog across our southeastern

On Sunday...a very impressive upper trough /characterized
by nearly 80 meter height falls/ is forecast to amplify across the
Great Basin. The resultant southwest flow across the Lee of the
New Mexico rockies should induce low level cyclogenesis. As the
upper low closes off somewhere over New Mexico...the surface
cyclone should deepen quickly. In response...moisture transport
across area should increase. With around 50 knots of middle level
flow...the very diffluent regime aloft and with the boundary layer
moistening...the stage will be set for another round of severe
weather. Taking a closer look at the areal extent of the best low
level appears that most of the coarser models are
fairly consistent with bringing 65+ degree dewpoints into our
southern zones. This appears plausible as there have not been any
recent intrusions of Continental air down into the western Gulf of
Mexico recently. While a Stout cap will be in place...30 to 40
meter height falls /indicative of large scale ascent/ will
overspread western zones on Sunday evening. A dryline is expected
to sharpen somewhere across the Big Country during the afternoon
hours on Sunday. Low level convergence coupled with the favorable
dynamics should prove sufficient to overcome the cap. Steep middle
level lapse rates should yield a very healthy instability profile
/3000+ j/kg of cape/ and 0-6 km bulk shear values of around 50
knots should Foster supercellular storm structures. With the steep
middle level lapse rates and a very "fat" cape profile...large hail
appears probable. In addition...the strengthening of the low level
jet /winds of around 30-35 kts/ around the 00-03 UTC time frame on
Monday will support a rather substantial tornado
threat...primarily across our western and southwestern zones. For appears that the best chances for precipitation will
remain confined to areas west of the Interstate 35 corridor on
Sunday afternoon and Sunday evening...with precipitation likely
overspreading the rest of north/central Texas Sunday night into
Monday morning.


Long term...
on Monday...more numerous shower and thunderstorm activity can be
expected as the Pacific front/dryline nudges eastward as the closed
low slowly treks eastward. A cold front will also sag southward
through Oklahoma before stalling out somewhere along the Red River.
Parameters for severe thunderstorms on Monday appear favorable...but
with the lack of any convective appears likely that
a very messy convective scene will unfold. That being said...deep
layer shear will still support organized thunderstorm structures
capable of large hail and damaging winds. Similar to Sunday...the
kinematic structure may also support a tornado risk. In
addition...heavy rain will be possible along the slowly sagging cold
front....especially along the Red River...and east of the Interstate
35 corridor. The cold front should sweep through all of
north/central Texas by Tuesday...ushering in cooler temperatures
and drier conditions. After a fairly active weather
appears that more tranquil conditions will be in place across
north/central Texas as a shift to more of an Omega pattern
/ridging across the central US with troughs along the coast/ sets
up for the remainder of the forecast period.



Preliminary point temps/pops...
Dallas-ft. Worth, Texas 88 62 87 64 72 / 5 5 20 40 60
Waco, Texas 89 61 86 65 78 / 10 5 20 40 50
Paris, Texas 85 53 85 58 68 / 10 5 10 40 60
Denton, Texas 86 59 86 61 70 / 5 5 20 50 60
McKinney, Texas 86 58 86 61 70 / 5 5 10 40 60
Dallas, Texas 89 64 88 64 73 / 10 5 10 40 60
Terrell, Texas 89 62 86 63 73 / 10 5 10 40 60
Corsicana, Texas 87 65 86 64 75 / 10 5 10 40 60
Temple, Texas 89 66 86 65 80 / 10 5 30 40 40
Mineral Wells, Texas 87 58 86 62 73 / 5 5 30 50 60


Forward watches/warnings/advisories...




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