Special Weather Statement, NWS Norman, OK

Area Forecast Discussion
National Weather Service Norman OK
1220 pM CDT SUN JUN 26 2016

.AVIATION...
Some lower cu, in the MVFR cat, is expected to gradually rise as
temps climb this aftn, so mainly VFR ceilings expected. Weak sfc
boundary across northern OK will act as focus for afternoon and
evening convection. Will keep a mention of tsra at WWR/GAG/PNC.
Scattered activity possible across remainder of the area this aftn
and evening, but chances remain too low to mention at this time.
Additional activity may develop late tonight in the PNC area.

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&&

.PREV DISCUSSION... /Issued 1054 AM CDT SUN JUN 26 2016/

.UPDATE...
Updated temperatures, minor updates to precipitation/weather, and
discussion about shower/thunder chances through the afternoon.

&&

.DISCUSSION...
Two areas of interest on water vapor imagery this morning. First,
a tightly wound short wave trough is evident wrapping north and
northeast over the Permian Basin. In response scattered showers
and isolated thunder continue to develop around the center.
Second, to the north, a convergence line is evident from near
Amarillo northeastward through the eastern Oklahoma Panhandle into
southwest/south central Kansas. 26/15Z surface analysis reveals a
weak surface boundary/trough within this same region of noticable
convergence. From visible imagery, it's more difficult to deduce,
as scattered to broken stratus remains spread across most of the
southern plains. These two features will provide the likely focus
for precipitation this afternoon and evening.

Latest mesoscale guidance from the TTU WRF and HRRR have come in
more aggressive than previous runs with convective development
through the mid to late afternoon across northern Oklahoma. Still
suggest taking their solutions with a grain of salt, as summer
time initiation is usually overdone by guidance. However, with the
presence of a decent forcing mechanism in the form of the surface
boundary confidence is good we'll have development, especially
given the evolving environment. MLCAPE values will be decent,
1500 to 2500 J/Kg. Deep layer shear values will be modest, 20 to
30 kts, enough to support some strong updrafts. Timing will remain
the greatest challenge. Through 1530Z, convective development
continues to slowly increase over west central Kansas. Expect this
activity to continue into the afternoon, with a storms slowly
pushing into northern Oklahoma through mid to late afternoon as
the surface boundary sinks southward.

Expect scattered showers and thunderstorms, with a few strong to
severe thunderstorms possible. Strong wind gusts and locally heavy
rainfall are the primary concerns. Convection last night in Kansas
resulted in areas of 2 to 3 inches of rain in some locations and
could similarly occur in northern Oklahoma this evening and
overnight.

Guidance hasn't been too keen on any appreciable convection in
southwestern Oklahoma and western north Texas in association with
the 500mb short wave. However, given the strength of the trough,
if it makes a decent northward push, scattered showers and
thunderstorms could develop over western north Texas and far
southwestern Oklahoma.

Kurtz

&&

.PREV DISCUSSION... /issued 636 AM CDT SUN JUN 26 2016/

DISCUSSION...
Please see the 12Z aviation discussion below.

AVIATION...
VFR will apply through the forecast period, although thunderstorms
are expected over GAG, WWR, and PNC later this afternoon. Winds
will remain below 15 kt today generally from the south.
Thunderstorms may dissipate after sunset this evening, but then
return later tonight. It is unclear, however, when they will
return. For now, will include PROB30s from around 03-08Z.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  93  74  92  73 /  20  20  40  50
Hobart OK         94  73  94  72 /  40  20  30  50
Wichita Falls TX  96  74  95  74 /  30  20  30  40
Gage OK           90  69  91  69 /  60  50  30  40
Ponca City OK     91  73  90  71 /  40  60  40  30
Durant OK         94  76  94  74 /  10  10  40  50

&&

.OUN Watches/Warnings/Advisories...
OK...None.
TX...None.
&&

04/30

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
1159 AM CDT SUN JUN 26 2016

OKZ004>048-050>052-TXZ083>090-270500-
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-
1159 AM CDT SUN JUN 26 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHERN...
WESTERN...CENTRAL...AND SOUTHERN OKLAHOMA...AND WESTERN NORTH
TEXAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT...

.THUNDERSTORMS...
THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS A PORTION
OF NORTHERN OKLAHOMA. THE MARGINAL RISK EXTENDS EAST AND NORTH OF
A LINE FROM NEAR FREEDOM TO TALOGA TO MULHALL TO MANNFORD.

ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL SLOWLY
DEVELOP IN SOUTHERN KANSAS AND NORTHERN OKLAHOMA MID TO LATE IN
THE AFTERNOON. A FEW STORMS COULD BECOME STRONG TO SEVERE IN THE
MID AFTERNOON INTO THE EVENING... WITH LOCALLY HEAVY RAINFALL
LEADING TO FLASH FLOODING AND DAMAGING WIND GUSTS ARE THE PRIMARY
HAZARDS. INCREASING COVERAGE OF RAIN AND THUNDERSTORMS OVERNIGHT
ACROSS NORTHERN OKLAHOMA MAY LEAD TO AN INCREASED CONCERN FOR
HEAVY RAINFALL AND FLOODING.

.SPOTTER AND EMERGENCY MANAGEMENT STATEMENT...

STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL ACROSS
NORTHERN OKLAHOMA SHOULD PREPARE FOR SEVERE WEATHER OPERATIONS
LATE THIS AFTERNOON AND TONIGHT.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY...

.THUNDERSTORMS...
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE EACH DAY THIS WEEK INTO
NEXT WEEKEND. HEAVY RAIN LEADING TO FLOODING WILL BE THE BIGGEST
CONCERN THROUGHOUT THE WEEK. NO ORGANIZED SEVERE WEATHER IS
EXPECTED BUT A FEW STRONG TO SEVERE STORMS MAY BE POSSIBLE AT
TIMES.

GET GRAPHICS AND MORE DETAILS AT WEATHER.GOV/NORMAN...AND FOLLOW
OUR WEATHER FORECAST OFFICE ON TWITTER AND FACEBOOK.

KURTZ

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
121 PM CDT SUN JUN 26 2016

OKZ014-015-261845-
ROGER MILLS OK-DEWEY OK-
121 PM CDT SUN JUN 26 2016

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN ROGER MILLS AND WEST
CENTRAL DEWEY COUNTIES UNTIL 145 PM CDT...

AT 119 PM CDT...STRONG THUNDERSTORMS WERE ALONG A LINE EXTENDING FROM
6 MILES NORTHWEST OF LEEDEY TO 6 MILES SOUTHWEST OF ANGORA...MOVING
NORTHEAST AT 10 MPH.

HAZARDS INCLUDE...
HAIL UP TO ONE-HALF INCH DIAMETER...
WIND GUSTS TO 40 MPH...
MINOR FLOODING IN AREAS OF POOR DRAINAGE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MONITOR THE WEATHER SITUATION CLOSELY AND BE ALERT FOR THREATENING
WEATHER CONDITIONS.

&&

LAT...LON 3579 9965 3586 9958 3587 9956 3589 9955
      3600 9944 3601 9926 3579 9941
TIME...MOT...LOC 1819Z 243DEG 8KT 3595 9940 3580 9956

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