Area Forecast Discussion
Issued by NWS Oklahoma City, OK

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FXUS64 KOUN 281233
AFDOUN

Area Forecast Discussion
National Weather Service Norman OK
633 AM CST Tue Feb 28 2017

.AVIATION...28/12z TAF Issuance...
Scattered to broken ceilings will remain spread across the region
through much of the period. For airfields along and east of I-35,
including KOKC/KOUN/KPNC, MVFR fog and ceilings will linger
through sunrise, with most sites seeing improvement in the mid-
morning hours. Winds will be a concern for aviators for a good
portion of the day, especially across northwestern Oklahoma
through the afternoon, where sustained southwest winds of 20 to
30 kts with gusts up to 45 kts are possible. KGAG and KWWR may see
the greatest impact from winds. There will also be a substantial
wind shift from northwest to southeast, beginning in the evening
and overnight. Southwest winds will shift out of the northwest and
remain gusty through the end of the period for most sites.

Kurtz

&&

.PREV DISCUSSION... /issued 353 AM CST Tue Feb 28 2017/

DISCUSSION...
Forecast focus is on Critical to Extremely Critical fire weather
conditions in western Oklahoma into far western north Texas today.

This morning, if you live along and east of I-35, the ground is
probably sweating... which is just fantastic. Dew points continue to
hover in the upper 50s to 60 across most of central and eastern
Oklahoma. Overnight, temperatures have held steady, increasing a few
degrees in some locations, and dew points will continue steadily
increase ahead of the dry line, which continues to shore up across
western Oklahoma, to the southwest, along the Caprock.

From 08z surface analysis, the surface trough stretches from
southeastern Nebraska to southeastern Colorado. With the eastward
push of the western trough across the Four Corners, the surface
trough will strengthen, developing a rather tight pressure gradient,
while slowly building east/southeastward. In response, strong,
rather impressive, southwest winds will develop today in western
Oklahoma and western north Texas. In combination with the developing
surface pressure gradient, low level (850 and 700mb) winds will be
stout, with an 850mb Jet approaching 50 kts by midday. This is
important to note, as skies will begin to break through the
afternoon in far western Oklahoma, with surface temperatures pushing
into the upper 70s near 80. RAP and NAM Bufr soundings suggest deep
mixing is possible, tapping into those upper winds, with momentum
transfer of a layer average 30 to 40 kts. A lot of this will depend
on cloud coverage and warm up, but this signal has shown itself for
a few days, and although we may not mix as aggressively as the models
suggest, confidence is good we`ll see sustained winds near 40 mph
for a few hours in far northwestern Oklahoma with gusts approaching
50 mph, enough for a high wind warning and a wind advisory for gusts
over 40 mph in the same vicinity and southward along the
Oklahoma/Texas Panhandle border.

Critical to Extremely Critical fire weather conditions will develop
across western Oklahoma and western north Texas. This is, of course,
in part, because of the strong winds, but also due to the strong dry
air advection that has been on going since yesterday. As the dry
line strengthens in western Oklahoma, Relative humidity values will
drop into the low teens for several hours through the afternoon.
These low RH values will combine with afternoon high temperatures in
the mid 80s in western north Texas to upper 70s in northwestern
Oklahoma and ERC-G values climbing above the 50th percentile. The
most critical conditions will develop across portions of western
north Texas and along far western Oklahoma, where the Red Flag
Warning remains in effect. At this time, did not convert any of the
going Fire Weather Watch to a Red Flag, but did expand the watch to
far north central Oklahoma, where winds and RH values may reach
Elevated to Near Critical.

Not to be out done by fire weather, still expect thunderstorms to
develop along the dry line later in the afternoon, into the evening,
across southeastern Oklahoma. Bufr soundings show a rather steep
inversion. This paired with persistent cloud cover over the region
through most of the day, initiation will likely be delayed until
well in the afternoon and early evening. Not a great setup, quite
messy to be honest. Expect some breaks in cloud cover by the late
afternoon, with MLCAPEs around 1000-1500 J/Kg. Accompanied by stout
deep layer shear values, damaging hail will be the primary concern
along with damaging winds. The chances for storms will be well east
and southeast of I-35 and will continue into the overnight hours,
before the arrival of the cold front from the north pushes any
remaining activity east and southeast by daybreak.

Into Wednesday, with the arrival of the cold front late Tuesday into
the morning hours, winds will shift out of the north and northwest,
and be quite breezy. This could have an impact on any remaining hot
spots and containment issues with fires that start on Tuesday. On
the bright side, temperatures will be much cooler, highs in the 50s
and low 60s.

For the rest of the week, dry and calm conditions are expected, with
a warm up beginning into Saturday ahead of an approaching surface
low through the weekend.

Kurtz

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  79  39  59  32 /  10  10   0   0
Hobart OK         78  37  60  30 /   0   0   0   0
Wichita Falls TX  83  41  62  32 /  10   0   0   0
Gage OK           78  31  57  25 /  10  10   0   0
Ponca City OK     78  37  57  29 /  10  10   0   0
Durant OK         76  47  63  36 /  30  30  10   0

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Fire Weather Watch from noon CST today through this evening for
     OKZ005>008-011>013-017>019-023>025-027>029-038-039-044-045.

     Red Flag Warning from noon today to 9 PM CST this evening for
     OKZ004-009-010-014>016-021-022-033>037.

     Wind Advisory from 11 AM this morning to 7 PM CST this evening
     for OKZ005-010-015-016-021-022-033-034-036.

     High Wind Warning from 11 AM this morning to 7 PM CST this
     evening for OKZ004-009-014.

TX...Fire Weather Watch from noon CST today through this evening for
     TXZ086-089-090.

     Red Flag Warning from noon today to 9 PM CST this evening for
     TXZ083>085-087-088.

     Wind Advisory from 11 AM this morning to 7 PM CST this evening
     for TXZ083-084-087.

&&

$$

03/04



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