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Area forecast discussion 
National Weather Service Norman OK
544 am CST Thursday Nov 26 2015

the 12z aviation discussion follows....


rain will spread NE across North Texas and OK this morning...bringing
lower ceilings and visibilities to the region. Conditions are
likely to be imc this afternoon at most taf sites. +Ra late this
afternoon and evening will bring visibilities down at times to
less than 1 sm. While there is a possibility of thunderstorms and rain...they should
be limited to isolated flashes of lightning in otherwise Ordinary
rain showers. A strong cold front will sweep southeast across the region today
and this evening...bringing abrupt wind shifts and swiftly falling
temperatures. The actual timing of the front may be an hour or two
different from the its speed is difficult to gauge at
this point. As the cold air continues to flow into the region
overnight...temperatures in northwest OK should fall below freezing.
Some freezing rain is likely after 06z...reaching as far as kelk-kcsm-
kjwg-kend by 12z. Low clouds...restricted visibilities...and areas
of freezing rain in the west...will continue tomorrow...with some improvement
beginning Saturday.


Previous discussion... /issued 452 am CST Thursday Nov 26 2015/

a strong cold front will pass through Oklahoma and North Texas
today and overnight...bringing major changes to our weather. At
the same time...exceptionally large quantities of moisture in the
atmosphere will result in heavy rain...mainly in the general
vicinity of the front...and in the colder air behind it.

At 430 am...the cold front was in far northwest Oklahoma...from
northwest of Alva to the Antelope Hills. This front will move
southeast through the day...reaching the Oklahoma City area early
this evening...Wichita Falls by midnight...and the southeast
corner of our forecast area near Durant tomorrow morning.
Temperatures will drop swiftly after frontal passage...generally
dropping almost immediately from the 60s to the 40s...and wind
chills will be mainly in the 20s and 30s in the colder airmass.

As the cold air continues to strengthen across the region...much
of western and northern Oklahoma...and parts of western North
Texas...will have temperature readings fall below freezing. The
rain will continue...resulting in freezing rain. Some sleet...and
maybe snow...will fall in far northwest Oklahoma at times...but we
currently expect freezing rain to be the main type of
precipitation northwest of the freezing line.

We have upgraded the Winter Storm Watch to an Ice Storm Warning as
confidence in significant ice accumulations...1/4 inch or
more...has risen. In addition...there is some potential for
significant ice accumulations a little bit east and south of our
former watch we have issued a Winter Storm Watch for a
thin area from Perry to Oklahoma City to Lawton to Vernon and Knox
City Texas. There was also a need to expand the Ice Storm Warning
into Hardeman and Foard counties in the current outlook
brings quite a bit of ice into those counties as well.

The eastern/southeastern edge of the watch/warning area will
probably only see accumulations on trees...power lines...and other
exposed/elevated surfaces. Travel problems are unlikely in those
areas...except where downed tree limbs might block a few streets.
Farther northwest...especially from around Hobart to Watonga...the
outlook is less desirable...and travel problems will be fairly bridges and overpasses will probably become
slippery...and greater accumulations of ice on trees/power lines
may become a serious problem. Warm ground temperatures should
preclude ice on the ground or non-elevated highways...except
possibly in northwest Oklahoma where colder temperatures will
hang around longer.

While the northwest half or so of our forecast area is dealing
with ice...the southeast half will likely see very heavy rainfall.
As mentioned earlier...there will be a lot of moisture for the
storm system to work with...and by the time it moves away on
Sunday and Monday...5 to 8 inches of rainfall is expected
along/southeast of I-44. The heaviest rain is expected in our far
southeast counties. A Flash Flood Watch was already in
effect...and for the far southeast counties...we are extending the
watch another 24 hours.

The weather finally settles down Sunday night...and a warming
trend begins on Monday. Temperatures will recover to near the
seasonal average around the middle of next week...with readings
ranging from the middle 40s to the middle 50s.


Preliminary point temps/pops...
Oklahoma City OK 64 33 33 30 / 90 100 90 80
Hobart OK 66 32 33 29 / 90 100 80 80
Wichita Falls Texas 68 36 37 32 / 80 100 90 90
gage OK 45 28 29 23 / 90 70 80 60
Ponca City OK 64 32 33 31 / 100 100 90 70
Durant OK 68 43 43 35 / 70 100 100 90


Oun watches/warnings/advisories...
OK...Winter Storm Watch from this evening through Saturday morning
for okz013-019-025-027>029-037-038.

Ice Storm Warning from 6 PM this evening to noon CST Saturday
for okz004>012-014>018-021>024-033>036.

Flash Flood Watch from this evening through Friday afternoon for

Flash Flood Watch from this evening through Saturday afternoon
for okz043-047-048-050>052.

Texas...Winter Storm Watch from this evening through Saturday morning
for txz085-087.

Ice Storm Warning from 6 PM this evening to noon CST Saturday
for txz083-084.

Flash Flood Watch from this evening through Friday afternoon for




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