Oklahoma Severe Weather Discussion - June 2011

[Bostonfan]

Little further east than what they were saying earlier. Looks like we could get lucky. Storms may fire east of OKC.

[venture]

Little further east than what they were saying earlier. Looks like we could get lucky. Storms may fire east of OKC.

That's why I said don't get hung up on the exact position. Most cases it has the storm alignment/configuration pretty close...but is off by 50-75 miles. Which could be that it is too far east, south, north, etc. RUC and NAM are further west. 06Z GFS is right on I-35.

[venture]

Central and NE OK getting upgraded to Moderate Risk.



MESOSCALE DISCUSSION 1316
NWS STORM PREDICTION CENTER NORMAN OK
1042 AM CDT MON JUN 20 2011

AREAS AFFECTED...EASTERN KS AND CENTRAL/EASTERN OK

CONCERNING...OUTLOOK UPGRADE

VALID 201542Z - 201645Z

CATEGORICAL MODERATE RISK...DRIVEN BY POTENTIALLY SIGNIFICANT
HAIL/WIND AND PERHAPS TORNADOES...WILL BE EXPANDED TO INCORPORATE
MUCH OF EASTERN KS AND CENTRAL/EASTERN PORTIONS OF OK /ROUGHLY OKC
METRO AND I-40 NORTH/. FOR ADDITIONAL DETAILS...SEE THE FORTHCOMING
DAY 1 OUTLOOK UPDATE WHICH WILL BE ISSUED BY 1630Z.

..GUYER.. 06/20/2011

[OKCMallen]

Interesting. I thought it felt a little volatile when it was so warm and windy so early this AM.

[venture]

New Outlook...

...CENTRAL/SRN PLAINS...
UNSEASONABLY STRONG UPPER LOW MOVING FROM CURRENT POSITION SE CO NEWD ACROSS WRN KS INTO SRN NEB BY 12Z TUE. 60-70KT 500MB JET MAX WITH ASSOCIATED STRONG ASCENT/DIVERGENCE SPREADING NEWD FROM CENTRAL HIGH PLAINS ACROSS KS INTO NEB THIS AFTERNOON. SURFACE LOW OVER W-CENTRAL KS WILL MOVE SLOWLY NNEWD INTO SRN NEB. THE DRY LINE EXTENDING FROM THE LOW SWD THRU FAR WRN OK/SWRN TX WILL SHIFT EWD BY MID AFTERNOON TO EXTEND ON A N/S AXIS VICINITY THE I-35 CORRIDOR.

VERY STRONG SLY WINDS AHEAD OF DRY LINE WILL WRAP NWWD THE MOIST AND UNSTABLE AIR MASS TO N OF SURFACE LOW INTO CENTRAL NEB.

THE STRONG LARGE SCALE ASCENT COUPLED WITH THE POST FRONTAL MOIST NLY FLOW WRN KS THIS AM HAS GENERATED ELEVATED SEVERE THUNDERSTORMS.


BY MID AFTERNOON CONDITIONS WILL RAPIDLY DEVELOP TO SUPPORT AN OUTBREAK OF SEVERE THUNDERSTORMS BOTH ALONG THE DRY LINE AND IN THE VERY FAVORABLE SHEAR AND LARGE SCALE ASCENT REGION TO THE N/NE OF THE SURFACE LOW ACROSS NEB.

THE STRONGLY SHEARED PROFILES AHEAD OF THE SURFACE LOW OVER ERN NEB COUPLED WITH MLCAPES CLIMBING TO AOA 2000 J/KG EXPECTED TO SUPPORT TORNADIC SUPERCELL DEVELOPMENT BY MID/LATE AFTERNOON. THERE IS THE POTENTIAL OF STRONG TORNADOES GIVEN THE ENVIRONMENT THAT WILL BE IN PLACE.

DOWN THE DRY LINE SCATTERED SUPERCELLS WILL DEVELOP AS THE CAP BREAKS BY MID/LATE AFTERNOON. BY THAT TIME MLCAPES WILL HAVE CLIMBED TO AOA 2500 J/KG SWD TO THE OK/TX BORDER WHICH WHEN COUPLED WITH THE PRESENCE OF THE MID LEVEL JET MAX AND VERY STEEP LAPSE RATES WILL RESULT IN A VERY LARGE HAIL POTENTIAL ALONG WITH DAMAGING DOWNBURST WINDS. IT NOW APPEARS COVERAGE OF BOTH THE HAIL AND WIND WILL BE SUFFICIENT TO UPGRADE THE RISK TO MDT AS FAR S AS THE OKC AREA .
THERE WILL ALSO BE THE POTENTIAL FOR TORNADOES GIVEN THE 50-60 KT OF SHEAR. FURTHER S INTO NCENTRAL TX THE EXPECTED COVERAGE WILL BE LESS BUT THERE IS STILL POTENTIAL OF VERY LARGE HAIL AND DAMAGING DOWNBURSTS.

UPSCALE ORGANIZATION OF ONE OR MORE CLUSTERS IS ONCE AGAIN POSSIBLE TONIGHT WITH THE RISK OF WIDESPREAD DAMAGING WINDS AS STORMS SPREAD INTO IA/MO.

[Thunder]

I hope this will be a fun day. I've been waiting every day lately and nothing.

[Kaye]

We certainly don't the damage this can cause though!

[venture]

Norman has a decent time line up now on when to expect the storms...

[Zac Green]

Yeah it looks like a decent day is going to shape up. Not many, if any tornadoes, but do not let your guard down with EF-0-1 equivalent straight line winds possible as well as HUGE hail.

Venture when do you think you will open up your chat? Later this afternoon?

[Boo1083]

After reading that it sounds like hail and wind is main threat, with isolated tornadoes possible ? Would tornadoes that form big large or long lived ?

[venture]

MESOSCALE DISCUSSION 1320
NWS STORM PREDICTION CENTER NORMAN OK
0134 PM CDT MON JUN 20 2011

AREAS AFFECTED...CENTRAL/EASTERN KS AND OK

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 201834Z - 202030Z

INCIPIENT DEEP CONVECTIVE DEVELOPMENT IS EXPECTED TO OCCUR BY AROUND
MID AFTERNOON ACROSS EAST-CENTRAL KS INTO PORTIONS OF CENTRAL
OK...AND A WATCH WILL BE NEEDED BY AROUND MID AFTERNOON.

AN INCREASE IN MID LEVEL CONVECTION...LIKELY JUST ABOVE AN ERODING
CAP VIA IMPLIED LARGE SCALE FORCING FOR ASCENT...HAS OCCURRED EARLY
THIS AFTERNOON IN NORTH-SOUTH BANDS ACROSS CENTRAL KS/NORTH-CENTRAL
OK COINCIDENT WITH A DRY LINE/SURFACE TROUGH DEMARCATED MOIST AXIS.
FURTHERMORE...A GRADUALLY INCREASING CU FIELD HAS ALSO BEEN RECENTLY
NOTED WITHIN THE HOTTER/DEEPLY MIXED AIR NEAR/WEST OF THE DRYLINE.
SPECIAL 18Z OBSERVED RAOBS FROM TOPEKA KS/NORMAN OK STILL REFLECT A
SUBSTANTIAL CAP AROUND 700-750 MB...BUT CONSIDERABLE
MOISTENING/COOLING HAS OCCURRED BELOW THE CAP IN EACH CASE SINCE
12Z.

AS THE CLOSED UPPER LOW CURRENTLY OVER THE SOUTH-CENTRAL HIGH PLAINS
SHIFTS ENE AND GRADUALLY TAKES ON A MORE NEGATIVE TILT AND
CONSIDERABLE HEIGHT FALLS OVERSPREAD THE REGION...AT LEAST SCATTERED
SURFACE BASED CONVECTION SHOULD DRAMATICALLY INCREASE THROUGH
MID/LATE AFTERNOON ESPECIALLY ACROSS EAST-CENTRAL KS/NORTH-CENTRAL
OK. VERY STRONG/BUT GRADUALLY BACKING FLOW ALOFT WILL SUPPORT
SUPERCELLS WITHIN A VERY STEEP LAPSE RATE AND MODERATE TO STRONGLY
UNSTABLE ENVIRONMENT. INITIAL MODE SUPERCELLS CAPABLE OF LARGE HAIL
WILL BE POSSIBLE. WHILE A HOT BOUNDARY LAYER/RELATIVELY HIGH
TEMPERATURE-DEWPOINT SPREADS WILL TEND TO CURB THE RISK...A TORNADO
THREAT CANNOT BE RULED OUT. OTHERWISE...DEEP LAYER SHEAR ORIENTED
PARALLEL TO THE INITIATING BOUNDARY...WITH A VEER-BACK-VEER PATTERN
NOTED IN FORECAST SOUNDINGS/OBSERVATIONAL DERIVED WINDS...IMPLIES A
CONGEALING/MORE LINEAR MODE THROUGH EARLY EVENING WITH A MARKEDLY
INCREASING DAMAGING WIND POTENTIAL ESPECIALLY GIVEN THE STEEP LAPSE
RATES/WATER LOADING.

..GUYER.. 06/20/2011


ATTN...WFO...TSA...TOP...ICT...OUN...DDC...

[venture]

Watch will be issued shortly. You can join us in the Live Chat at http://www.storm-scope.com



MESOSCALE DISCUSSION 1324
NWS STORM PREDICTION CENTER NORMAN OK
0321 PM CDT MON JUN 20 2011

AREAS AFFECTED...CENTRAL/EASTERN OK AND NORTH-CENTRAL TX

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 202021Z - 202145Z

AS A SUPPLEMENT TO EARLIER MESOSCALE DISCUSSION 1320...VISIBLE
SATELLITE IMAGERY OVER THE PAST HOUR REFLECTS INCREASING HIGH BASED
CU ALONG THE DRYLINE FROM WEST-CENTRAL OK SOUTHWESTWARD INTO TX NEAR
THE ABILENE AREA. AS LARGE SCALE FORCING FOR ASCENT CONTINUES TO
OVERSPREAD THE REGION AND REMAINING CINH WANES...IT SEEMS LIKELY
THAT AT LEAST SCATTERED DEEP CONVECTION WILL INITIATE/INCREASE
THROUGH THE 21Z-23Z TIMEFRAME. A WATCH WILL LIKELY BE ISSUED SHORTLY
FOR AT LEAST PORTIONS OF CENTRAL/EASTERN OK...WITH A WATCH ALSO
POSSIBLE ACROSS PORTIONS OF NORTH-CENTRAL TX WHERE SOMEWHAT MORE
ISOLATED SEVERE DEVELOPMENT IS ANTICIPATED. AN INITIAL SUPERCELLULAR
LARGE HAIL/SOME TORNADO THREAT WILL EXIST ESPECIALLY ACROSS
OK...BEFORE A DAMAGING WIND THREAT LIKELY EVOLVES THROUGH EARLY
EVENING.

..GUYER.. 06/20/2011

[venture]

Ww 525 severe tstm ok tx 202045z - 210400z
axis..55 statute miles east and west of line..
25ne pnc/ponca city ok/ - 45w sep/stephenville tx/ ..aviation coords.. 50nm e/w /60se ict - 49ese abi/ hail surface and aloft..3.5 inches. Wind gusts..70 knots.
Max tops to 550. Mean storm motion vector 24030.

[venture]

This is a PDS Severe Thunderstorm Watch. These are exceptionally rare (last one in OK was 2006ish...and only 3rd one this year).



URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 525
NWS STORM PREDICTION CENTER NORMAN OK
345 PM CDT MON JUN 20 2011

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

MUCH OF CENTRAL OKLAHOMA
MUCH OF NORTHWEST TEXAS

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 345 PM UNTIL
1100 PM CDT.

...THIS IS A PARTICULARLY DANGEROUS SITUATION...

WIDESPREAD DAMAGING WINDS
WIND GUSTS TO 80 MPH LIKELY
WIDESPREAD LARGE HAIL
HAIL TO 3.5 INCHES IN DIAMETER LIKELY
ISOLATED TORNADOES

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55
STATUTE MILES EAST AND WEST OF A LINE FROM 25 MILES NORTHEAST OF
PONCA CITY OKLAHOMA TO 45 MILES WEST OF STEPHENVILLE TEXAS. 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 523...WW 524...

DISCUSSION...THUNDERSTORMS SHOULD DEVELOP ALONG THE DRY LINE ON WRN
EDGE OF WATCH BY 22Z. STORMS WILL RAPIDLY BECOME SEVERE GIVEN THE
AVAILABLE VERY UNSTABLE AIR MASS IN ADVANCE OF THE UNSEASONABLY
STRONG UPPER TROUGH . SUPERCELLS WILL BE INITIAL MODE BUT QUICKLY
EVOLVE INTO LINE SEGMENTS AND BOWS. VERY LARGE HAIL ALONG WITH A
POTENTIAL OF SIGNIFICANT DAMAGING WINDS WILL ACCOMPANY BOTH THE
SUPERCELLS AND THE MORE LINEAR MODE THAT EVOLVES BY THIS EVENING. IN
ADDITION BRIEF TORNADOS ARE POSSIBLE WITH BOTH MODES

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 3.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM
MOTION VECTOR 24030.


PROBABILITY TABLE:
PROB OF 2 OR MORE TORNADOES : 20%
PROB OF 1 OR MORE STRONG /F2-F5/ TORNADOES : 05%
PROB OF 10 OR MORE SEVERE WIND EVENTS : 90%
PROB OF 1 OR MORE WIND EVENTS >= 65 KNOTS : 80%
PROB OF 10 OR MORE SEVERE HAIL EVENTS : 90%
PROB OF 1 OR MORE HAIL EVENTS >= 2 INCHES : 70%
PROB OF 6 OR MORE COMBINED SEVERE HAIL/WIND EVENTS : >95%

&&
ATTRIBUTE TABLE:
MAX HAIL /INCHES/ : 3.5
MAX WIND GUSTS SURFACE /KNOTS/ : 70
MAX TOPS /X 100 FEET/ : 550
MEAN STORM MOTION VECTOR /DEGREES AND KNOTS/ : 24030
PARTICULARLY DANGEROUS SITUATION : YES

[Thunder]

Please tell us we will have another round tomorrow. Maybe a better one?

[kevinpate]

Please tell us we will have another round tomorrow. Maybe a better one?

You're an odd lil' duck at times. But here's some ugliness from north of us last night to tide you over. Call it Rains, Trains and Running Pains.

http://news.yahoo.com/video/us-15749...dwest-25695965

[Thunder]

Omg omg omg awesome tornadoes!!! Wowowowowowowowowow!!!!!!!

[USG'60]

Change your shorts now, Thunder.

[Achilleslastand]

Wheres the{mild]cold front we were supposed to get?
I guess a 4 degree difference constitutes a cold front lol.

[BG918]

Back to our typical summer pattern...looks like Oklahoma will be hot and dry for at least the next week into the holiday weekend.

[ou48A]

Is there any sign of any tropical activity that might move into the northern or northwestern part of the Gulf of Mexico?

It looks like it’s going to take several tropical systems to break the back of the drought in much of the south and southern plains.
This drought is a historical weather event that is not getting enough attention IMHO.

[Bunty]

Wheres the{mild]cold front we were supposed to get?
I guess a 4 degree difference constitutes a cold front lol.

That was a back door cold front. It didn't make it to your back door. The high 70's and 80's it produced in northeastern Oklahoma for highs were nice while it lasted for a day.

[BG918]

Is there any sign of any tropical activity that might move into the northern or northwestern part of the Gulf of Mexico?

Nothing right now. It has been unusually quiet so far in the tropics. Usually there has at least been one or two tropical storms in the Gulf or Caribbean by the end of June.

We've been complaining about our drought in Oklahoma but Texas is in a much more dire situation, especially as we head into our hot and dry season in the Southern Plains.

[ou48A]

Arlene?

http://www.stormpulse.com/atlantic

[Thunder]

Arlene?

http://www.stormpulse.com/atlantic

Its going in the wrong direction!!!!! >_<

How much rain did we get this morning?