Oklahoma Severe Weather Discussion - April 2012

[venture]

SPC has brought in the slight risk officially to far NW OK tomorrow. This is a hatched area pointing out the chance for some significant severe weather. Very large hail and tornadoes are the main threat.

[venture]

Outlook for this evening. Could see a small complex of storms develop over the Northern Panhandles and SW KS. The complex would then move ESE/SE into NW OK by 10PM and then start to die out around 1-2AM. Nothing dramatic right now.

[Bunty]

Was anyone aware that it is Friday the 13th?

Yes, it was back on that awful day earlier this April. Interestingly, enough, like Stillwater, Norman can now claim it has had the luck of having a destructive tornado occur on Friday the 13th. Stillwater's was on June 13th, 1975. Only one heavily destructive tornado has happened there since then.

[venture]

Slight Risk today mainly far North and NE OK. Chances start to go up tomorrow.

[ou48A]

for Saturday

http://www.spc.noaa.gov/products/outlook/day2otlk.html
...OK/N TX WWD THROUGH THE TX PANHANDLE...
TSTM POTENTIAL IS EXPECTED TO REMAIN LIMITED DURING THE DAY ALONG
STALLING FRONT FROM NRN TX INTO THE OZARKS/SRN MO DUE TO A CAPPING
INVERSION AND WEAK FRONTAL CONVERGENCE. THEREAFTER...A STRENGTHENING
SLY NOCTURNAL LLJ WILL CONTRIBUTE TO NWD DESTABILIZATION OVER THE
SRN PLAINS FROM N TX AND OK INTO THE PANHANDLES. ELEVATED STORMS
WILL LIKELY DEVELOP WITHIN THIS ZONE OF ISENTROPIC ASCENT/STRONG WAA
SATURDAY NIGHT. A BAND OF 40-50 KT SWLY MIDLEVEL WINDS EXTENDING
FROM NM ACROSS OK/SRN KS WILL RESULT IN EFFECTIVE BULK SHEAR
BECOMING MORE FAVORABLE /40-50 KT/ TO SUPPORT ORGANIZED STORMS.
ACTIVITY SHOULD DEVELOP FROM S-N WITH MODELS NOW INDICATING STRONGER
MUCAPE 1000-1500 J/KG SAT NIGHT/EARLY SUN MORNING. THIS COMBINED
WITH STEEP MIDLEVEL LAPSE RATES SHOULD PROMOTE STORMS PRODUCING
SEVERE HAIL. THE GREATEST POTENTIAL FOR SEVERE STORMS WILL BE FROM
CENTRAL/SWRN OK INTO ERN PARTS OF THE TX PANHANDLE...AND THUS...A
SLIGHT RISK AREA HAS BEEN INTRODUCED FOR THIS REGION SAT NIGHT.

THERE IS SOME INDICATION FOR SURFACE BASED STORMS SAT EVENING INTO
THE OVERNIGHT PERIOD...BUT CONFIDENCE IS LOWER WITH THIS THREAT. IF
STORMS CAN BECOME SURFACE BASED...THEN THERE WOULD BE A THREAT FOR
DAMAGING WINDS AND A TORNADO THREAT COULD NOT BE RULED OUT.

[ou48A]

Mike Morgan say Tornadoes are possible on Sunday

[ou48A]

CH 9 Gary England said that we may have severe weather and heavy rain late Saturday into Sunday and that Sunday looks turbulent.

[venture]

Slight Risk today is along I-44 and about 75 miles on either side of it from Tulsa to the TX border.

Latest SPC Outlook:

...SRN PLAINS...
SURFACE FRONT CURRENTLY DRAPED ACROSS PARTS OF W TX EXTENDING NEWD
NEAR THE I-44 CORRIDOR IN OK IS FORECAST TO MOVE LITTLE DURING THE
DAY. NEAR AND S OF THIS BOUNDARY...STRONG BOUNDARY LAYER HEATING
--TEMPS RISING INTO THE 80S-- WITHIN A SLY LOW LEVEL FETCH OF
LOWER-MID 60S DEWPOINTS WILL YIELD 2000-3000 J/KG MLCAPE. MODEL
FORECAST SOUNDINGS SHOW THE CAP WEAKENING CONSIDERABLY TOWARDS 00Z.
SUITE OF CONVECTION-ALLOWING MODELS HOWEVER TEND TO LIMIT TSTM
COVERAGE TO ISOLD CHANCES UNTIL THE MID-EVENING HOURS AS A CNTRL TX
LLJ INTENSIFIES /40 KTS/ AND ISENTROPIC LIFT INCREASES. DESPITE
COVERAGE/CAPPING CONCERNS...A BELT OF 35-50 KT H5 FLOW OVERTOP THE
REGION WILL BE FAVORABLE FOR ISOLD SUPERCELL DEVELOPMENT...ESP. NEAR
THE DRYLINE/FRONT INTERSECTION OVER WRN N-CNTRL TX/SWRN OK. A LARGE
TO VERY LARGE HAIL THREAT WILL BE POSSIBLE FOR ANY SURFACE-BASED
DAYTIME SUPERCELLS THAT DEVELOP. BACKED LOW LEVEL FLOW INVOF THE
FRONT WITH SOME INCREASE IN LOW LEVEL SHEAR TOWARDS DUSK MAY LEND AN
ISOLD TORNADO RISK WHERE SURFACE T/TD SPREADS LOWER BEFORE MLCINH
INCREASES...ACTING TO TEMPER THE TORNADO POTENTIAL. DURING THE
OVERNIGHT...TSTM COVERAGE IS FORECAST TO INCREASE /GENERALLY N OF
THE RED RIVER/ WITH MAINLY A LARGE HAIL/ISOLD DMGG WIND RISK
LINGERING INTO THE OVERNIGHT HOURS.

[venture]

Svr watch is now active for most of central and sw ok until 2 am. Storms starting fire in nw texas. Chat is open.

[venture]

Watch area is being monitored for upgrade to tornado watch after dark as conditons improve for tornadic development.

[Easy180]

Might be interesting in Bricktown tonight

[venture]

Latest HRRR guidance is pretty much on tap right now. Large supercell in NW TX right moving east should stay south of the Red River. HRRR is saying in the next hour we should see additional development from SW OK into NW TX. It is predicting what appears to be several supercells popping up and moving ENE/NE. That first wave will go through then a break as the storms in NW TX wll eventually take a turn and head north as storms develop north of the front. This will likely setup the heavy rain and some embedded severe hail/wind.

We'll see if it verifies.

[venture]

Storm developing in W a s h i t a county is get a decent hail core on it. Severe weather could be occuring soon in NW W a s h i t a, SE Custer and NW Caddo counties.

Reminder the new chat room address: http://www.weatherspotlight.com/chat.html

[venture]

First warning is up. Storm has a very interesting configuration...will need to watch it.

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORMAN OK
918 PM CDT SAT APR 28 2012

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
SOUTH CENTRAL BLAINE COUNTY IN OKLAHOMA...
NORTHWESTERN CADDO COUNTY IN OKLAHOMA...
NORTHWESTERN CANADIAN COUNTY IN OKLAHOMA...
EXTREME SOUTHEASTERN CUSTER COUNTY IN OKLAHOMA...
UNTIL 1000 PM CDT
* AT 917 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL AND
DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR
HYDRO...MOVING EAST AT 20 MPH.

[venture]

Rotation is increasing in the Caddo Co storm and it will be heading into the Metro Area / Canadian County here in the next half hour-ish. Large hail should be expected.

[venture]

Keeping an eye on things. Rotation is pretty high up in the storm as it stands now.

[venture]

2nd cell getting its act together near Cordell in W a s h i t a County. Storms are moving east at 20-25. Tornado threat could increase as it nears I-34 as winds start to turn more east there.

[venture]

Ww 201 tornado ok 290335z - 290700z
axis..40 statute miles east and west of line..
25sse fsi/fort sill ok/ - 35nw cqb/chandler ok/ ..aviation coords.. 35nm e/w /26ne sps - 36ese end/ hail surface and aloft..3 inches. Wind gusts..60 knots.
Max tops to 500. Mean storm motion vector 25025.


BULLETIN - IMMEDIATE BROADCAST REQUESTED TORNADO WATCH OUTLINE UPDATE FOR WT 201 NWS STORM PREDICTION CENTER NORMAN OK 1035 PM CDT SAT APR 28 2012 TORNADO WATCH 201 IS IN EFFECT UNTIL 200 AM CDT FOR THE FOLLOWING LOCATIONS OKC015-017-027-031-033-049-051-067-073-081-083-087-109-119-125- 137-141-290700- /O.NEW.KWNS.TO.A.0201.120429T0335Z-120429T0700Z/ OK . OKLAHOMA COUNTIES INCLUDED ARE CADDO CANADIAN CLEVELAND COMANCHE COTTON GARVIN GRADY JEFFERSON KINGFISHER LINCOLN LOGAN MCCLAIN OKLAHOMA PAYNE POTTAWATOMIE STEPHENS TILLMAN ATTN...WFO...OUN...

[venture]

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 201
NWS STORM PREDICTION CENTER NORMAN OK
1035 PM CDT SAT APR 28 2012

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

SOUTHWEST THROUGH CENTRAL OKLAHOMA

EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 1035 PM
UNTIL 200 AM CDT.

SEVERAL TORNADOES
ISOLATED INTENSE TORNADOES POSSIBLE
SCATTERED DAMAGING WINDS TO 70 MPH
SCATTERED LARGE HAIL
ISOLATED HAIL TO 3.0 INCHES IN DIAMETER POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 40 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES SOUTH SOUTHEAST OF
FORT SILL OKLAHOMA TO 35 MILES NORTHWEST OF CHANDLER OKLAHOMA.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU1).

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.

OTHER WATCH INFORMATION...CONTINUE...WW 200...

DISCUSSION...SUPERCELLS THAT FORMED JUST W OF SW-NE FRONT THROUGH
SW/CNTRL OK EXPECTED TO CONTINUE MOVING ENE THROUGH EARLY SUN. AS
THE STORMS ENCOUNTER WARMER/MORE MOIST AIR E OF BOUNDARY...INCREASE
IN THETA-E MAY SUFFICIENTLY ENHANCE LOW LVL MESO STRENGTH TO POSE A
RISK FOR TORNADOES...IN ADDITION TO ON-GOING RISK FOR LARGE
HAIL/HIGH WIND.

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 25025.

TORNADO WATCH PROBABILITIES FOR WT 0201
NWS STORM PREDICTION CENTER NORMAN OK
1038 PM CDT SAT APR 28 2012


WT 0201
PROBABILITY TABLE:
PROB OF 2 OR MORE TORNADOES : 40%
PROB OF 1 OR MORE STRONG /F2-F5/ TORNADOES : 30%
PROB OF 10 OR MORE SEVERE WIND EVENTS : 40%
PROB OF 1 OR MORE WIND EVENTS >= 65 KNOTS : 20%
PROB OF 10 OR MORE SEVERE HAIL EVENTS : 60%
PROB OF 1 OR MORE HAIL EVENTS >= 2 INCHES : 30%
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/ : 25025
PARTICULARLY DANGEROUS SITUATION : NO

[venture]

MESOSCALE DISCUSSION 0617
NWS STORM PREDICTION CENTER NORMAN OK
1047 PM CDT SAT APR 28 2012

AREAS AFFECTED...CNTRL AND WRN OKS INTO NWRN TX

CONCERNING...SEVERE THUNDERSTORM WATCH 200...

VALID 290347Z - 290545Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 200
CONTINUES.

SCATTERED SUPERCELLS EXIST FROM NWRN TX INTO CNTRL OK. TWO CELLS
WERE N OF THE SURFACE BOUNDARY OVER CNTRL OK...BUT WERE MOVING
MOSTLY IN AN EWD DIRECTION. ALTHOUGH CELLS ARE FIGHTING SOME CAPPING
AND CIN...FAVORABLE WIND PROFILES ARE LIKELY TO KEEP THESE CELLS
GOING FOR A WHILE. AS THEY APPROACH THE SURFACE FRONT...THEY WILL
ENCOUNTER SLIGHTER WARMER AND MOISTER LOW LEVEL AIR MASS...WHICH
COULD HELP IN VERTICAL ACCELERATIONS DOWN LOW. THIS...ALONG WITH
MORE THAN ADEQUATE LOW LEVEL SHEAR...COULD RESULT IN A BRIEF
TORNADO.

TO THE S...LARGE HAIL WAS THE MAIN THREAT OVER NWRN TX WHERE LOW
LEVEL T/TD SPREADS WERE LARGER. SOME OF THESE CELLS WERE LEFT
MOVING...AND WILL EXIT THE WATCH INTO PORTIONS OF THE ERN TX
PANHANDLE...BUT AN ADDITIONAL WATCH IS NOT EXPECTED AT THIS TIME.

..JEWELL.. 04/29/2012

[venture]

Catching up a bit here...



URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 205
NWS STORM PREDICTION CENTER NORMAN OK
805 PM CDT SUN APR 29 2012

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

SOUTH CENTRAL AND SOUTHEASTERN KANSAS
WESTERN AND CENTRAL MISSOURI
NORTHERN OKLAHOMA

EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 805 PM UNTIL
300 AM CDT.

SCATTERED DAMAGING WINDS TO 70 MPH
SCATTERED LARGE HAIL TO 2.0 INCHES IN DIAMETER
ISOLATED TORNADOES

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 160
STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH
NORTHEAST OF CHANUTE KANSAS TO 40 MILES SOUTH SOUTHWEST OF ENID
OKLAHOMA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).

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 203...WW 204...

DISCUSSION...TSTMS...INCLUDING A FEW SUPERCELLS...EXPECTED TO
INCREASE IN COVERAGE AND STRENGTH ALONG DIFFUSE CORRIDOR OF
WAA/CONFLUENCE FROM N CNTRL OK NEWD INTO SE KS AND SW MO. AT THE
SAME TIME...SW KS FORWARD-PROPAGATING MCS EXPECTED TO CONTINUE
MOVING E OR PERHAPS ESE INTO S CNTRL KS AND NW OK...POSSIBLY WITH
SOME INCREASE IN STRENGTH AS IT ENCOUNTERS RICHER MOISTURE SUPPLY
WITH EWD EXTENT. BOTH AREAS OF STORMS COULD YIELD SVR HAIL/LOCALLY
DMGG WIND. LOW LVL WINDS ARE NOT EXPECTED TO APPRECIABLY INCREASE
AFTER NIGHTFALL. HOWEVER...TORNADO THREAT WILL BE NON-ZERO...MAINLY
WITH WAA ACTIVITY...GIVEN MOIST LOW LVL ENVIRONMENT/MODEST LOW LVL
DIRECTIONAL SHEAR. A MORE WIDESPREAD TORNADO THREAT WOULD APPEAR TO
REQUIRE FAVORABLE STORM-SCALE/BOUNDARY INTERACTIONS THAT ARE NOT
APPARENT ATTM.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM
MOTION VECTOR 25030.



MESOSCALE DISCUSSION 0624
NWS STORM PREDICTION CENTER NORMAN OK
0733 PM CDT SUN APR 29 2012

AREAS AFFECTED...SWRN/S-CNTRL KS...ERN OK PANHANDLE...NRN TX
PANHANDLE...NWRN OK

CONCERNING...SEVERE THUNDERSTORM WATCH 203...

VALID 300033Z - 300200Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 203
CONTINUES.

BOWING MCS WAS LOCATED FROM SWRN KS INTO FAR NERN NM AT 0015Z.
AIRMASS IN THE IMMEDIATE VICINITY OF THIS ACTIVITY IS CHARACTERIZED
BY TEMPERATURES IN THE MID 70S AND DEWPOINTS IN THE MID TO UPR 40S.
SURFACE OBSERVATIONS ALSO DEPICT A STRENGTHENING COLD POOL
ASSOCIATED WITH THE MCS...WITH A 20+ F TEMPERATURE CHANGE LOCATED
ACROSS THE GUST FRONT. DURING THE NEXT FEW HRS...SHORT-TERM MODEL
GUIDANCE INDICATES A 20-30 KT SLY LLJ WILL DEVELOP OVER THE SRN
PLAINS...WHICH WILL AID IN THE N-NWWD ADVECTION OF HIGHER THETA-E
AIR LOCATED OVER OK AND NWRN TX...WHERE SURFACE DEWPOINTS ARE IN THE
60S. THIS MAY FAVOR MCS PROPAGATION TOWARD THE SE INTO THE MORE
UNSTABLE AIRMASS. IF THIS TAKES PLACE...SVR WEATHER THREAT WILL
SPREAD INTO S-CNTRL KS...NWRN OK AND THE NRN TX PANHANDLE...AND MAY
REQUIRE EITHER SPATIAL EXTENSION OF WW 203...OR A NEW DOWNSTREAM WW.

..GARNER.. 04/30/2012


ATTN...WFO...ICT...OUN...DDC...AMA...ABQ...

[venture]

Very large hail keeps developing in the line in Northern OK. HRRR continues to show storms forming into a large complex and diving Southeast overnight. Damaging wind will be main threat with it and then heavy rain.

[venture]

Fyi


bulletin - eas activation requested
tornado warning
national weather service norman ok
959 pm cdt sun apr 29 2012


the national weather service in norman has issued a


* tornado warning for...
Southwestern kay county in oklahoma...
* until 1030 pm cdt


* at 954 pm cdt...national weather service meteorologists detected
a severe thunderstorm capable of producing a tornado. This
dangerous storm was located near billings...moving northeast at 25
mph.


* locations impacted include...
Tonkawa.

[venture]

Slight Risk today for much of the state. Tornado risk is mainly Western OK along with very large hail. Hail/Damaging Winds possible in Central areas later. As it looks now...always subject to change.

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0725 AM CDT MON APR 30 2012

VALID 301300Z - 011200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CENTRAL AND
SOUTHERN PLAINS...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE MID MS
AND OH VALLEYS...

MORNING WATER VAPOR IMAGERY SHOWS BROAD CYCLONIC FLOW OVER MOST OF
THE WESTERN...PLAINS...AND MIDWEST STATES. A SERIES OF SHORTWAVE
TROUGHS EMBEDDED IN THIS FLOW REGIME WILL TRACK ACROSS THE CENTRAL
PLAINS INTO THE OH VALLEY...PROVIDING A AXIS OF SHOWERS AND
THUNDERSTORMS FROM WEST TX INTO WV/PA.

...CENTRAL/SOUTHERN PLAINS...
WIDESPREAD THUNDERSTORMS HAVE BEEN ONGOING OVERNIGHT ACROSS PARTS OF
KS/OK/MO. THESE STORMS HAVE RESULTED IN A WELL-DEFINED OUTFLOW
BOUNDARY THAT EXTENDS ROUGHLY FROM AMA-SPS-ADM-FSM. EASTERLY LOW
LEVEL WINDS ON THE NORTH SIDE OF THE BOUNDARY WILL HELP TO TRANSPORT
AMPLE MOISTURE WESTWARD INTO THE TX PANHANDLE. MOST MODEL SOLUTIONS
AGREE ON STORMS FORMING ALONG THE DRYLINE/REMNANT OUTFLOW BOUNDARY
BETWEEN 19-22Z...AS A WEAK SHORTWAVE TROUGH NOW NEAR THE 4-CORNERS
AREA APPROACHES THE REGION. THE 12Z AMA RAOB ALSO SUPPORTS RATHER
EARLY INITIATION WITH STEEP LAPSE RATES AND ONLY A MINIMAL CAP.
STRONG DEEP LAYER EFFECTIVE SHEAR AND MEAN FLOW ORTHOGONAL TO
DRYLINE WILL PROMOTE DISCRETE SUPERCELL DEVELOPMENT WITH VERY LARGE
HAIL POSSIBLE. THE TORNADO POTENTIAL WILL BE DEPENDENT ON THE
EVOLUTION OF THE REMNANT OUTFLOW BOUNDARY...BUT THERE DOES APPEAR TO
BE SOME RISK OF A FEW TORNADOES DURING THE EVENING FROM SOUTHWEST KS
INTO THE TX PANHANDLE AND SOUTHWEST OK. DURING THE EVENING...STORMS
MAY GROW UPSCALE AND SPREAD EASTWARD ACROSS PORTIONS OF
WESTERN/CENTRAL OK WITH AN CONTINUED RISK OF HAIL AND DAMAGING
WINDS.

[Roadhawg]

I noticed that KOCO spent from 10 to 10:30 doing nothing but covering the storm activity.