Special Weather Statement, NWS Norman, OK

Area Forecast Discussion
National Weather Service Norman OK
636 PM CDT Tue Jun 6 2017

.DISCUSSION...
The 00Z aviation discussion follows....

&&

.AVIATION...
Scattered TSRA over western Kansas will extend into northwest
Oklahoma this evening and perhaps overnight, possibly affecting
TAF sites KGAG and KWWR this evening. There is a lot of
uncertainty as to how far south the storms will reach later
tonight, but they are likely to affect parts of the northwest
quadrant of Olahoma, and may extend as far south as KHBR, KLAW,
KOKC, and KOUN late tonight. Prior to sunset, storms, and even
showers, may occasionally produce rather strong downdrafts...and
outflow near ground level. This effect should diminish fairly
quickly after sunset.

CmS
&&

.PREV DISCUSSION... /issued 337 PM CDT Tue Jun 6 2017/

DISCUSSION...
The primary forecast issue is the chance of showers/storms this
week.

Through Wednesday, subtle shortwave troughs embedded within the
northwest flow will provide ascent for isolated to scattered
showers/storms.

The first shortwave trough is approaching from the northwest this
evening. Isolated to scattered thunderstorms have developed across
Kansas with approach of the wave. Convective-allowing models are
consistent that these storms will shift southward into northern
Oklahoma this evening. Steep low-level lapse rates, large DCAPE
(>=1000 J/kg), and large temperature-dewpoint spreads indicate
gusty winds will be the primary threat with any of the stronger
storms.

There is uncertainty on how far south and east the storms will
survive as some guidance suggests remnant storms as far south as
I-40 and as far east as I-35--so opted to add low probabilities as
far southeast as central Oklahoma for later tonight.

For Wednesday, drier and slightly cooler air is expected as a
surface ridge retrogrades to the southwest. A second shortwave
trough is expected to pass by the Texas/Oklahoma panhandles late
Wednesday. Showers/storms may affect western Oklahoma and adjacent
north Texas late afternoon/evening in association with this wave.

By Thursday night into Friday, increasing isentropic ascent
(augmented by a strengthening low-level jet) will result in
showers/storms with the highest probabilities from I-35 westward.
Isentropic ascent may result in another (lower) chance of
showers/storms Friday night into Saturday morning.

By the upcoming weekend, northwest flow aloft will transition
toward southwest flow. Expect gusty, southerly winds Saturday
through Monday with temperatures in the upper 80Fs to 90Fs. On
Tuesday, an approaching cold front and/or dryline will result in a
chance of thunderstorms--especially across northern and western
Oklahoma.

Mahale

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  63  80  59  82 /  20  10   0   0
Hobart OK         65  82  61  84 /  20  10  10  10
Wichita Falls TX  65  85  63  85 /   0  10  10  10
Gage OK           63  79  60  82 /  30  20  10  10
Ponca City OK     60  79  56  81 /  10  10   0   0
Durant OK         67  84  61  84 /   0  10   0   0

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...None.
TX...None.
&&

17/23/23

Hazardous Weather Outlook...CORRECTED
National Weather Service Norman OK
1235 PM CDT Tue Jun 6 2017

OKZ004>048-050>052-TXZ083>090-071715-
Harper-Woods-Alfalfa-Grant-Kay-Ellis-Woodward-Major-Garfield-
Noble-Roger Mills-Dewey-Custer-Blaine-Kingfisher-Logan-Payne-
Beckham-Washita-Caddo-Canadian-Oklahoma-Lincoln-Grady-McClain-
Cleveland-Pottawatomie-Seminole-Hughes-Harmon-Greer-Kiowa-Jackson-
Tillman-Comanche-Stephens-Garvin-Murray-Pontotoc-Coal-Cotton-
Jefferson-Carter-Johnston-Atoka-Love-Marshall-Bryan-Hardeman-
Foard-Wilbarger-Wichita-Knox-Baylor-Archer-Clay-
1235 PM CDT Tue Jun 6 2017

This hazardous weather outlook is for portions of northern...
western...central...and southern Oklahoma...and western
north Texas.

.DAY ONE...Today and Tonight...

.Thunderstorms...
A few thunderstorms will be possible late this afternoon and
tonight across portions of northern Oklahoma, and perhaps central
Oklahoma. The strongest storms will be capable of hail up to the
size of half dollars, gusty winds, and brief heavy rain.
Widespread severe weather is not anticipated, although a couple of
severe storms will be possible.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday...

.Thunderstorms...
Shower and thunderstorm chances will continue Wednesday into
Thursday across extreme western Oklahoma. Higher thunderstorm
chances will then arrive by Friday along and west of interstate
35. Severe storms are not expected at this time.

Get graphics and more details at weather.gov/norman...and follow
our weather forecast office on Twitter and Facebook.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
721 PM CDT TUE JUN 6 2017

OKZ005-006-070100-
Alfalfa OK-Woods OK-
721 PM CDT TUE JUN 6 2017

...SIGNIFICANT WEATHER ADVISORY FOR Alfalfa and northeastern Woods
Counties Until 800 PM CDT...

AT 720 PM CDT, a strong thunderstorm was located 4 miles southeast
of Driftwood, moving south at 15 MPH. Another strong thunderstorm
was located 4 miles north of Alva, moving south at 15 MPH.

HAZARDS INCLUDE...
Hail up to one-half inch diameter...
Wind gusts to 50 MPH...

Locations impacted include...
Alva, Cherokee, Jet, Burlington, Dacoma, Amorita, Byron, Lambert,
Ingersoll, Great Salt Plains Lake, Driftwood, Capron and Hopeton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the weather situation closely and be alert for threatening
weather conditions.

&&

LAT...LON 3700 9822 3699 9818 3662 9815 3663 9877
      3700 9870
TIME...MOT...LOC 0015Z 9DEG 12KT 3683 9831

MBS