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Area forecast discussion...corrected 
National Weather Service Norman OK
341 PM CDT Tuesday Apr 21 2015

the primary focus over the coming several days remains severe
weather potential each day through Friday.

With southwesterly winds and full sun...temperatures have warmed
nicely today. Scattered showers and storms will likely develop
across West Texas and eastern New Mexico and drift eastward this
evening and overnight...merging into one or more storm clusters.
Some uncertainty remains as to how strong these storms may be once
they reach the western Oklahoma border...but at least some
potential will exist for sporadic large hail and damaging wind
gusts this evening and early tonight...mainly across western
Oklahoma. Rain and a few thunderstorms should move into central
Oklahoma around sunrise and linger into the morning hours.

An enhanced risk of severe storms remains for
Wednesday...primarily across the southern third of Oklahoma into
North Texas. In response to early day showers/storms...a
front/outflow boundary will likely move southward to near or just
south of the Red River by middle afternoon tomorrow. With daytime
heating and convergence along this boundary...scattered
thunderstorms are likely to develop by late afternoon...from the
eastern Texas Panhandle down into far southwestern Oklahoma and
western North Texas. With a fair amount of instability and wind
shear in place...the environment will support severe storms
capable of large hail and damaging winds. A narrow window of
opportunity may exist for a couple of tornadoes if storms can
remain surface based and move along the boundary during the late
afternoon/evening hours. One limiting factor for tornadoes will be
the tendency for storms to develop along or just north of the
boundary...becoming elevated quickly. Thunderstorm outflows are
likely to lead to storm mergers and a southeastward moving storm
complex tomorrow evening into tomorrow night...with a continuing
threat of large hail and damaging winds.

At least some severe potential will exist once again on
Thursday...primarily along and south of the Red River...where
greater instability and wind shear will exist...though the better
severe potential will reside across northern and eastern Texas.

Friday still looks to be a potentially significant severe weather
day for parts of the central and Southern Plains and lower
Mississippi Valley region. Todays European and GFS models have
come into slightly better agreement...though the GFS remains the
faster of the two solutions. The NAM is a good compromise of these
two...and have opted to lean toward its depiction. A dryline looks
to mix east to near or just east of the I-35 corridor by middle
afternoon Friday. Much uncertainty remains on the level
destabilization that may the larger scale GFS/ec models
depict widespread precipitation and cloud cover in the warm sector
east of the dryline. However...assuming even modest
instability...wind shear will be favorable for supercells...and
all associated severe weather threats...including tornadoes. At
this time...much uncertainty remains with respect to precisely
where the dryline will end up...and where storms will ultimately
develop. Even though most models would suggest the greater threat
will reside east of I-35...even a slight shift in dryline position
may have a great outcome on what unfolds. Anyone living from
Kansas to Texas...east to Missouri...Arkansas...and Louisiana
should closely monitor this potential setup.

As we head into next weekend...cooler conditions look to prevail
as a weak front moves through the area Saturday. Showers and
storms may come back into the picture sometime Sunday night or
early Monday...but confidence is low as models remain inconsistent
with one another.



Preliminary point temps/pops...
Oklahoma City OK 54 69 55 71 / 20 60 40 30
Hobart OK 53 72 55 72 / 40 60 40 20
Wichita Falls Texas 56 77 59 78 / 20 40 50 30
gage OK 49 63 46 67 / 40 40 30 20
Ponca City OK 48 64 46 67 / 30 30 20 20
Durant OK 55 76 61 75 / 20 60 60 30


Oun watches/warnings/advisories...



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