Oklahoma Severe Weather Discussion - March 2012

[Roadhawg]

What's this about a potential gulley washer expected over the state next week?

I saw something about that... figures I just took the top down on my jeep, but I would rather have the much needed rain.

[adaniel]

Well I was planning on washing, waxing, and detailing my car on Saturday to get all of the winter gunk off. Knowing my luck, if I skip it it won't rain at all, and if I do we will get 5 inches of rain.

[OKCisOK4me]

Wax it! :-)

[MDot]

Wax it 2x's better than normal, then maybe we'll get 10 inches of rain. =)

[OKCisOK4me]

Our good friend Mike Morgan called a potential OKC drought buster and Nick Winkler on NEWS9 indicated potential heavy rains. Seems to be some agreement there.

[SoonerDave]

Surely Venture, our fearless leader, will give us the benefit of his updated wisdom at any time....

Got kids leaving on a church trip on Monday, trying to figure out weather...

[venture]

I'll try to get an update posted tomorrow for most of next week and including the severe weather risk for tomorrow. Working early mornings right now has my schedule a bit wonky. :-)

[sacolton]

I need enough time to build an ark and get two of each kind inside.

[Roadhawg]

I need enough time to build an ark and get two of each kind inside.

Me too... two blondes, two redheads, two brunettes......

[catch22]

Me too... two blondes, two redheads, two brunettes......

Post of the day award!

[Dulahey]

[Dulahey]

This goes right along with La nina fading away right now into normalcy.

[adaniel]

That weather forecast looks like something you would see in Houston this time of year, not OKC.

[venture]

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1256 AM CDT FRI MAR 16 2012

VALID 161200Z - 171200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER THE SRN HIGH PLAINS...

...SYNOPSIS...

A PROGRESSIVE QUASI-ZONAL SYNOPTIC PATTERN WILL PERSIST INTO FRIDAY
WITH A SERIES OF WEAK IMPULSES MOVING THROUGH THIS REGIME. ONE SUCH
VORT MAX MOVING INTO SRN AZ AS OF EARLY FRIDAY MORNING WILL REACH
THE SRN HIGH PLAINS LATER THIS AFTERNOON. SEVERAL MCVS NOW OVER THE
OH VALLEY WILL ADVANCE EAST INTO THE MID ATLANTIC REGION. AT THE
SURFACE A QUASI-STATIONARY FRONT DRAPED ACROSS THE GREAT LAKES WILL
BEGIN TO LIFT BACK NWD AS A WARM FRONT. DRYLINE WILL PERSIST FROM
THE SRN HIGH PLAINS NEWD INTO THE CNTRL PLAINS AREA. OTHERWISE
SEVERAL CONVECTIVE OUTFLOW BOUNDARIES WILL PERSIST OVER THE OH AND
TN VALLEY AREAS.

...SRN AND CNTRL PLAINS...

STEEP 7.5-8.5 C/KM LAPSE RATES HAVE OVERSPREAD LOW 60S F DEWPOINTS
OVER THE SRN-CNTRL PLAINS AND MS VALLEY WARMS SECTOR. THIS HAS
RESULTED IN MODERATE INSTABILITY...AND WITH DAYTIME HEATING MLCAPE
WILL LIKELY INCREASE TO 2000-3000 J/KG. MUCH OF THIS REGION SHOULD
REMAIN CAPPED TO SURFACE BASED STORMS DURING THE DAY OWING TO THE
WARM EML BASED BETWEEN 850-750 MB. HOWEVER...DIABATIC WARMING WILL
AUGMENT MIXING IN VICINITY OF THE DRYLINE OVER WRN TX DURING THE
AFTERNOON. THIS IN CONJUNCTION WITH FORCING FOR ASCENT ATTENDING THE
PROGRESSIVE VORT MAX SHOULD PROMOTE ISOLATED TO WIDELY SCATTERED
THUNDERSTORM DEVELOPMENT BY LATE AFTERNOON FROM WRN TX INTO SWRN OK.
A 40-50 KT MID LEVEL JET ATTENDING THE SHORTWAVE TROUGH WILL RESULT
IN 40-50 KT EFFECTIVE SHEAR ACROSS WRN TX WITH WEAKER SHEAR NWD INTO
OK AND KS. VERY LARGE HAIL WILL BE THE PRIMARY THREAT...BUT A SMALL
WINDOW WILL EXIST FOR ISOLATED TORNADOES AS THE LLJ STRENGTHENS
DURING THE EARLY EVENING AND BEFORE THE BOUNDARY LAYER DECOUPLES.
ACTIVITY MAY BEGIN TO STRUGGLE LATER IN THE EVENING AS CONVECTIVE
INHIBITION INCREASES.

SEVERE THREAT WITH NWD EXTENT INTO KS IS MORE UNCERTAIN GIVEN
STRENGTH OF CAP AND LIMITED DEEP FORCING FOR ASCENT. VERTICAL SHEAR
WILL BE WEAK IN THIS REGION...BUT SHOULD STORMS DEVELOP THE
THERMODYNAMIC ENVIRONMENT WILL PROMOTE A THREAT FOR ISOLATED LARGE
HAIL AND DAMAGING WIND. AT THIS TIME...COVERAGE IS EXPECTED TO
REMAIN LESS THAN 15%.

[venture]

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT FRI MAR 16 2012

VALID 181200Z - 191200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS A LARGE PORTION OF THE
PLAINS STATES...

...SYNOPSIS...
WITH LARGE-SCALE RIDGING TO FURTHER INCREASE ACROSS THE ERN HALF OF
THE U.S. THIS PERIOD...PRIMARY FOCUS IN TERMS OF SEVERE WEATHER
POTENTIAL WILL SHIFT WWD TO THE PLAINS REGION.

THIS SEVERE POTENTIAL WILL BE ASSOCIATED WITH THE ADVANCE OF A
LARGE/SHARP TROUGH COVERING MUCH OF WRN NOAM. AS THIS TROUGH
ADVANCES SLOWLY BUT STEADILY EWD...A SURFACE COLD FRONT WILL EXIT
THE ROCKIES AND EMERGE INTO THE HIGH PLAINS DURING THE SECOND HALF
OF THE PERIOD...PRECEDED BY A DRYLINE. THE DRYLINE -- AND LATER THE
COLD FRONT -- SHOULD FOCUS A SLOWLY-MOVING AXIS OF STRONG/SEVERE
CONVECTION FROM EVENING INTO THE OVERNIGHT HOURS.

...THE PLAINS...
AS THE UPPER TROUGH ADVANCES AND A COLD FRONT BEGINS SHIFTING INTO
THE HIGH PLAINS...LOW-LEVEL MOISTURE WILL CONTINUE TO ADVECT NWD
WITHIN THE PRE-FRONTAL/PRE-DRYLINE BOUNDARY LAYER. THIS COMBINED
WITH STEEP LAPSE RATES AND DIURNAL HEATING WILL RESULT IN MODERATE
DESTABILIZATION...THOUGH CAPPING SHOULD HINDER CONVECTIVE
DEVELOPMENT INTO THE AFTERNOON.

EVENTUALLY HOWEVER...EXPECT STORM DEVELOPMENT TO OCCUR -- AIDED BY
THE WEAKENING CAP AS HEIGHT FALLS ALOFT OVERSPREAD THE REGION
ENHANCING LOW-LEVEL CONVERGENCE.

AS STORMS DEVELOP...STRENGTHENING FLOW FIELD ALOFT WILL RESULT IN
FAVORABLE SHEAR FOR SUPERCELLS...AND THUS STORMS SHOULD QUICKLY
ORGANIZE/BECOME SEVERE. ATTM...MODEST MOISTURE /DEWPOINTS ONLY IN
THE UPPER 50S TO NEAR 60 IN MOST AREAS/ AND ASSOCIATED/FAIRLY DEEP
BOUNDARY LAYER SUGGESTS PRIMARY SEVERE POTENTIAL WILL BE VERY LARGE
HAIL AND LOCALLY DAMAGING WINDS. WHILE OVERALL STORM COVERAGE MAY
REMAIN FAIRLY ISOLATED THROUGH THE AFTERNOON...AN INCREASE IN
CONVECTION INTO THE EVENING COMBINED WITH SLOW EWD MOVEMENT OF THE
FRONT/DRYLINE SUGGEST EVENTUAL COVERAGE OF SEVERE EVENTS SHOULD
WARRANT 30% SEVERE PROBABILITY LINES.

..GOSS.. 03/16/2012

[venture]

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 79
NWS STORM PREDICTION CENTER NORMAN OK
350 PM CDT FRI MAR 16 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

WESTERN OKLAHOMA
THE TEXAS SOUTH PLAINS AND EASTERN TEXAS PANHANDLE

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 350 PM UNTIL 900
PM CDT.

SCATTERED LARGE HAIL
ISOLATED HAIL TO 2.5 INCHES IN DIAMETER POSSIBLE
WIDELY SCATTERED DAMAGING WINDS TO 70 MPH
ISOLATED TORNADOES

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 65
STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES EAST
NORTHEAST OF GAGE OKLAHOMA TO 55 MILES SOUTH SOUTHEAST OF LUBBOCK
TEXAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION...CONTINUE...WW 78...

DISCUSSION...DEEPENING CUMULUS DEVELOPMENT HAS BEEN NOTED IN RECENT
VISIBLE SATELLITE IMAGERY ALONG THE DRYLINE FROM JUST SW OF LBB TO
JUST NE OF PAMPA. CONTINUED DAYTIME HEATING WILL FURTHER WEAKEN
CONVECTIVE INHIBITION...AND A WEAK LARGE SCALE ASCENT WILL HELP
CONDITION THE ENVIRONMENT FOR MORE STORM DEVELOPMENT AS A WEAK
MIDLEVEL TROUGH MOVES NEWD FROM ERN NM. VERTICAL SHEAR IS ONLY
MARGINALLY FAVORABLE FOR SPLITTING SUPERCELLS...BUT STRONG
INSTABILITY WILL SUPPORT A RISK FOR LARGE HAIL WITH ANY SUSTAINED
STORMS. LATER THIS EVENING...STORMS COULD COALESCE INTO A CLUSTER
OR TWO ACROSS NW TX AND SW OK...WITH AN ATTENDANT RISK FOR LARGE
HAIL AND DAMAGING WINDS.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 27020.

[Snowman]

Welcome change in drought outlook for our region, it is the first time in probably a year to 18 months that they are saying showing improvement verses drought being persistent/likely to intensify and having a couple spots in central and western Oklahoma not indicating drought present.

[venture]

Severe weather possible, if not likely, in the state Sunday and Monday. Outlook for the OKC metro is for things to be very close on timing with either day.

Sunday Main Risks: Very Large Hail (2"+), Damaging Winds, and a Couple Tornadoes.
Monday Main Risks: Very Large Hail (2"+), Localized Damaging Winds, and Tornadoes.

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1156 PM CDT SAT MAR 17 2012

VALID 181200Z - 191200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE CNTRL AND
SRN PLAINS...

...SYNOPSIS...
A FULL LATITUDE UPPER TROUGH WILL GRADUALLY SHIFT EWD FROM THE GREAT
BASIN ACROSS THE ROCKIES DURING THE DAY...EMERGING INTO THE HIGH
PLAINS BY MON MORNING. WHILE THE PRIMARY VORTICITY CENTER WILL BE
MOVING ACROSS THE FOUR CORNERS AREA DURING THE DAY...A LEAD
SHORTWAVE TROUGH IS EXPECTED TO MOVE OUT OF NRN MEXICO NEWD ACROSS
TX EARLY SUN AND INTO OK AND KS FROM MID TO LATE AFTERNOON. BEHIND
THIS LEAD WAVE...GRADUAL HEIGHT FALLS WILL PERSIST WITH THE MAIN
BODY OF THE TROUGH.

AT THE SURFACE...A BROAD AREA OF LOW PRESSURE WILL CONSOLIDATE OVER
THE NRN HIGH PLAINS...WITH A DISTINCT LOW PRESSURE TROUGH EXTENDING
SWD INTO W TX AND A COLD FRONT DEVELOPING OVER WY...CO AND NM. AHEAD
OF THIS TROUGH...BROAD SLY FLOW WILL BRING LOWER 60S F DEWPOINTS AS
FAR N AS IA AND IL. AN EML WILL EXIST OVER THE WARM
SECTOR...PREVENTING SURFACE BASED DEVELOPMENT FOR MUCH OF THE DAY.

TO THE E...A WEAK VORTICITY CENTER...ENHANCED BY ONGOING CONVECTION
THIS EVENING OVER IL AND IND...WILL PERSIST AS IT TRAVELS EWD ALONG
AND N OF THE OH RIVER. THIS FEATURE IS LIKELY TO FOCUS ADDITIONAL
THUNDERSTORM DEVELOPMENT DURING THE DAY.

...OK INTO ERN KS MIDDAY INTO AFTERNOON...
LIFT WITH THE LEAD SHORTWAVE IS LIKELY TO RESULT IN SCATTERED RAIN
AND STORMS DEVELOPING OVER NWRN TX INTO OK NEWD INTO SRN/ERN KS BY
LATE AFTERNOON. FORECAST SOUNDINGS INDICATE THAT THIS ACTIVITY COULD
BE ELEVATED ABOVE THE CAPPING INVERSION...WHERE STEEP LAPSE RATES
WILL EXIST. EVEN SO...WITH FAVORABLE EFFECTIVE SHEAR...SOME OF THIS
ACTIVITY COULD PRODUCE SOME HAIL.

...NWRN TX INTO WRN OK AND KS...
CONVERGENCE ALONG THE DRYLINE IS EXPECTED TO INCREASE AFTER ABOUT
21Z AS MASS FIELDS READJUST TOWARD THE WRN TROUGH AND AWAY FROM THE
LEAD SHORTWAVE. WITH STRONG HEATING AND NEARLY DRY ADIABATIC LAPSE
RATES THROUGH A DEEP LAYER W OF THE DRYLINE...A NARROW ZONE OF
STRONG INSTABILITY IS EXPECTED FROM WRN KS INTO THE ERN OK/TX
PANHANDLE SWD INTO NWRN TX. HERE...SHEAR PROFILES WILL STRONGLY
FAVOR SUPERCELLS...CAPABLE OF LARGE...PERHAPS VERY LARGE
HAIL...DAMAGING WIND GUSTS AND A COUPLE TORNADOES. WHILE LOW LEVEL
HODOGRAPHS DO ENLARGE AFTER 00Z...SO WILL CONVECTIVE INHIBITION WITH
BACKING SURFACE WINDS BRINGING RELATIVELY COOLER...YET STILL MOIST
AIR NWWD MEETING WITH THE COLD FRONT AROUND 03Z. ADDITIONAL ACTIVITY
IS LIKELY DUE TO STRONG FORCING...BUT MORE OF A LINEAR STORM MODE IS
EXPECTED...WITH PERHAPS HYBRID SUPERCELLS AND BOWING SEGMENTS
CAPABLE OF WIND AND HAIL.

THE SEVERE THREAT APPEARS MORE CONDITIONAL FARTHER N INTO NEBRASKA
WHERE STORMS MAY BE MORE ISOLATED.

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0100 AM CDT SUN MAR 18 2012

VALID 191200Z - 201200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MO VALLEY AREA
SWD/SSWWD TO THE LOWER RIO GRANDE VALLEY...

...SYNOPSIS...
HIGHLY AMPLIFIED UPPER FLOW FIELD TO CONTINUE ACROSS THE U.S. THIS
PERIOD...AS A VERY LARGE TROUGH MOVES SLOWLY OUT OF THE ROCKIES
TOWARD THE GREAT PLAINS. MEANWHILE...A CORRESPONDING DOWNSTREAM
RIDGE WILL AFFECT BASICALLY THE ENTIRE ERN U.S. E OF THE MS VALLEY.

AT THE SURFACE...HIGH PRESSURE WILL PREVAIL OVER THE ERN AND WRN
PORTIONS OF COUNTRY...WHILE A N-S COLD FRONT ASSOCIATED WITH THE
ADVANCING TROUGH CROSSES THE PLAINS STATES THROUGH THE PERIOD. THIS
FRONT WILL BE THE FOCUS FOR A N-S ZONE OF STORMS EXTENDING FROM THE
CANADIAN TO THE MEXICAN BORDER.

...MID MO VALLEY SSWWD TO THE LOWER RIO GRANDE VALLEY...
SHOWERS AND STORMS -- AND POSSIBLY ONGOING SEVERE POTENTIAL --
SHOULD EXTEND ACROSS PARTS OF KS/OK/TX AT THE START OF THE
PERIOD...WITH WEAKER CONVECTION EXTENDING NNEWD INTO THE MID MO
VALLEY REGION. THE ONGOING PRECIPITATION AND CLOUD COVER -- BEING
CARRIED CONTINUALLY NNEWD BY THE STRONG SLY/MERIDIONAL FLOW ALOFT --
SHOULD HINDER DESTABILIZATION POTENTIAL...AND THUS LIKEWISE LIMIT
ASSOCIATED SEVERE WEATHER POTENTIAL N OF THE SRN PLAINS WHERE LOWER
PROBABILITY THREAT FOR HAIL/WIND IS EXPECTED.

THE FOCUS FOR GREATER SEVERE POTENTIAL REMAINS FROM ROUGHLY ERN
KS/MO SWD -- PARTICULARLY INTO SERN OK/WRN MO AND SWD ACROSS E TX ON
THE SERN FRINGE OF ONGOING STORMS. AS AFTERNOON DESTABILIZATION
PUSHES MIXED-LAYER CAPE INTO THE 1000 TO 2000 J/KG RANGE ACROSS THIS
REGION...STORMS WILL INTENSIFY/REDEVELOP ACROSS THIS AREA THROUGH
PEAK HEATING.

AS STRONG /60 TO 70 KT/ SWLY FLOW AT MID LEVELS OVERSPREADS THE
MOIST/UNSTABLE BOUNDARY LAYER FEATURING SSELY PRE-FRONTAL
WINDS...DEVELOPING STORMS WITHIN THE FAVORABLY SHEARED ENVIRONMENT
WILL QUICKLY BECOME SEVERE/SUPERCELLULAR...WITH VERY LARGE HAIL AND
LOCALLY DAMAGING WINDS POSSIBLE. A COUPLE OF TORNADOES MAY ALSO
OCCUR -- GIVEN AMPLE LOW-LEVEL SHEAR AND THE MOIST BOUNDARY LAYER
FORECAST IN THIS REGION. OVERNIGHT...INCREASINGLY LINEAR
ORGANIZATION OF THE CONVECTION IS EXPECTED ALONG THE SLOWLY
ADVANCING FRONT. WHILE SEVERE THREAT CONTINUES INTO THE OVERNIGHT
HOURS...THREAT FOR HEAVY RAIN SHOULD ALSO INCREASE GIVEN OVERALL
SLOW MOVEMENT OF THE CONVECTIVE BAND AND POTENTIAL FOR TRAINING
CONVECTION.

[venture]

Extended Outlook...

Sun 3/18 - Severe Storms West 1/2, Temps 60s/70s.
Mon 3/19 - Severe Storms East 1/2, Temps 60s/70s.
Tue 3/20 - Rain/Storms East 1/2, Temps 50s/60s.
Wed 3/21 - Chance of Rain/Storms Central/South, Temps 40s-60s. Could be an interesting day with upper low overhead. Shear doesn't look insane right now, but could be a candidate for some low topped storms spinning up a few weak funnels.
Thu 3/22 - Rain/Storms most areas except fair East/West...Heaviest in Central, Temps 50s/60s. Much the same as Weds. Heavy rain possible.
Fri 3/23 - Mostly Dry, Temps 60s.
Sat 3/24 - Dry. Temps 70s.
Sun 3/25 - Dry with an outside chance of an isolated storm NW. Temps 70s.
Mon 3/26 - Mostly Dry, very slight chance of storms West - some severe if they form. Temps 70s.
Tue 3/27 - Chance of storms late Central, some severe. Temps 70s/80s.
Wed 3/28 - Chance of storms, mainly Central/South, some severe. Temps 70s/80s.
Thu 3/29 - Chance of storms, Central/East - some severe (it is Spring afterall). Temps 70s/80s.
Fri 3/30 - Chance of Rain west. Temps 60s/70s.
Sat 3/31 - Chance of rain/storms - mainly SW. Temps 60s/70s.
Sun 4/1 - Chance of rain/snow/sleet mix Central under upper load - rain elsewhere. Temps 40s/50s.
Mon 4/2 - Chance of rain/storms East and South. Temps 60s/70s.

[venture]

Tornado Watch will be issued soon.



MESOSCALE DISCUSSION 0273
NWS STORM PREDICTION CENTER NORMAN OK
0231 PM CDT SUN MAR 18 2012

AREAS AFFECTED...ERN OK/TX PANHANDLES...FAR WRN OK...WRN N TX

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 181931Z - 182130Z

THE SEVERE THREAT WILL INCREASE OVER THE NEXT 1-3 HOURS AND
THUNDERSTORMS ARE EXPECTED TO INITIATE AROUND 21Z. LARGE HAIL WILL
BE THE MAIN THREAT BUT A FEW TORNADOES WILL ALSO BE POSSIBLE. A WW
WILL LIKELY BE NEEDED WITHIN THE NEXT HOUR OR SO.

19Z VIS SAT IMAGERY SHOWED CUMULUS BEGINNING TO DEVELOP ACROSS THE
TX S PLAINS E OF LBB AHEAD OF A DRYLINE EXTENDING SWD FROM WRN KS
THROUGH SWRN TX. AS TEMPERATURES HAVE WARMED INTO THE MID AND UPPER
70S THIS AFTERNOON...ONLY WEAK MLCIN REMAINS WITH MLCAPE VALUES NOW
APPROACHING 2000 J/KG. WITH ADDITIONAL HEATING REMAINING CAP WILL
QUICKLY ERODE AND CONVECTIVE INITIATION IS EXPECTED WITHIN THE NEXT
COUPLE OF HOURS. WHILE THE MAIN UPPER LEVEL FORCING REMAINS WELL TO
THE WEST ACROSS AZ/NM WITH THE UPPER LEVEL TROUGH...HEIGHT FALLS
HAVE BEEN OCCURRING ACROSS THE REGION THIS AFTERNOON AND RECENT
PROFILER DATA HAVE INDICATED AN INCREASE IN MIDLEVEL FLOW STREAMING
INTO THE MCD AREA. GIVEN BULK SHEAR VALUES OF 35-45 KTS AND MIDLEVEL
LAPSE RATES AROUND 7.5 DEG C/KM...ORGANIZED SUPERCELL STORMS CAPABLE
OF LARGE HAIL ARE EXPECTED. WHILE LARGE HAIL WILL INITIALLY BE THE
MAIN THE THREAT...AS THE UPPER TROUGH MOVES EWD AND STRONGER DEEP
LAYER FORCING ENCROACHES UPON THE REGION TOWARD 00Z...LOW LEVEL
HODOGRAPHS WILL BECOME MORE FAVORABLE FOR TORNADO DEVELOPMENT.
THEREFORE...A TORNADO WATCH WILL LIKELY BE ISSUED.

..LEITMAN.. 03/18/2012

[venture]

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 80
NWS STORM PREDICTION CENTER NORMAN OK
315 PM CDT SUN MAR 18 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

FAR WESTERN OKLAHOMA AND THE EASTERN OKLAHOMA PANHANDLE
PARTS OF WEST CENTRAL/NORTHWEST INTO THE EASTERN TEXAS
PANHANDLE
PANHANDLE

EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 315 PM UNTIL
1000 PM CDT.

SEVERAL TORNADOES
WIDESPREAD LARGE HAIL
HAIL TO 3.0 INCHES IN DIAMETER LIKELY
WIDELY SCATTERED DAMAGING WINDS TO 70 MPH

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
MILES EAST AND WEST OF A LINE FROM 55 MILES NORTH NORTHWEST OF
GAGE OKLAHOMA TO 45 MILES WEST SOUTHWEST OF ABILENE TEXAS. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU0).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

DISCUSSION...VISIBLE SATELLITE IMAGERY SHOWS DEEPENING CUMULUS ALONG
AND E OF THE DRYLINE FROM BIG SPRING TX NWD THROUGH THE CENTRAL/ERN
TX PANHANDLE...WITH THE MOST LIKELY AREA FOR STORM DEVELOPMENT
BETWEEN CHILDRESS AND BIG SPRING BY 21Z. THE STORM ENVIRONMENT IS
BECOMING MORE FAVORABLE FOR SUPERCELLS AS BOTH DEEP-LAYER AND
LOW-LEVEL SHEAR INCREASE IN CONJUNCTION WITH DAYTIME HEATING/
DESTABILIZATION. VERY LARGE HAIL WILL BE POSSIBLE WITH ANY OF THE
SUSTAINED SUPERCELLS THROUGH THE EVENING...AND A FEW TORNADOES WILL
ALSO BE POSSIBLE GIVEN TEMPERATURE-DEWPOINT SPREADS GENERALLY AOB 20
F AND INCREASING EFFECTIVE SRH THROUGH THE EVENING.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 24030.



TORNADO WATCH PROBABILITIES FOR WT 0080
NWS STORM PREDICTION CENTER NORMAN OK
0317 PM CDT SUN MAR 18 2012

WT 0080
PROBABILITY TABLE:
PROB OF 2 OR MORE TORNADOES : 60%
PROB OF 1 OR MORE STRONG /F2-F5/ TORNADOES : 20%
PROB OF 10 OR MORE SEVERE WIND EVENTS : 20%
PROB OF 1 OR MORE WIND EVENTS >= 65 KNOTS : 20%
PROB OF 10 OR MORE SEVERE HAIL EVENTS : 80%
PROB OF 1 OR MORE HAIL EVENTS >= 2 INCHES : 70%
PROB OF 6 OR MORE COMBINED SEVERE HAIL/WIND EVENTS : 90%

&&
ATTRIBUTE TABLE:
MAX HAIL /INCHES/ : 3.0
MAX WIND GUSTS SURFACE /KNOTS/ : 60
MAX TOPS /X 100 FEET/ : 500
MEAN STORM MOTION VECTOR /DEGREES AND KNOTS/ : 24030
PARTICULARLY DANGEROUS SITUATION : NO

[venture]

First severe storm is just to the SW of Childress moving NE. Could be SW OK with in the next 2-3 hours.

---

Update:

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORMAN OK
455 PM CDT SUN MAR 18 2012

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
GREER COUNTY IN SOUTHWESTERN OKLAHOMA...
HARDEMAN COUNTY IN NORTH CENTRAL TEXAS...
HARMON COUNTY IN SOUTHWESTERN OKLAHOMA...
EXTREME WEST CENTRAL JACKSON COUNTY IN SOUTHWESTERN OKLAHOMA...

* UNTIL 600 PM CDT

* AT 453 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
A SEVERE THUNDERSTORM CAPABLE OF PRODUCING LARGE DAMAGING HAIL UP
TO TWO INCHES IN DIAMETER AND DAMAGING WINDS IN EXCESS OF 65 MPH.
THIS STORM WAS LOCATED NEAR HOLLIS...MOVING NORTHEAST AT 40 MPH.

* LOCATIONS IMPACTED INCLUDE...
MANGUM...HOLLIS...GRANITE...DUKE...GOULD...WILLOW. ..VINSON...
GOODLETT...BRINKMAN...HESTER...MADGE...MCKNIGHT...
MCQUEEN AND LAZARE.

[venture]

Things are starting to spin a bit out there. First tornado warning for a rapidly rotating wall cloud producing a funnel just southeast of Guthrie, TX...about 75 miles SSE of Altus.

Two main areas of concern for the body of Oklahoma....
1) Cell in Crowell Co, TX. Rotating is picking up a bit, developing hook. Moving NE at 30 mph. It will cross the boarder into Jackson County in little over an hour.

2) Another is in Childress County, TX...moving NNE at around 30. Will cross into Oklahoma with in the hour near or just north of Hollis in Harmon County.

[venture]

Storm #1 is now tornado warnings. Rotation is increasing in Storm #2 just north of Hollis.

[venture]

Might see a tornado warning soon for Harmon and Greer counties. The rotation is pretty strong with the storm now.