Chase 2010 - Day 23 Discussion

[Nick F]

Please discuss what looks to be an action packed chase later today, with tour 3 hitting the ground running full on. 15% probs of tornadoes (Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point), 60% probs large hail. Will give a forecast of where I would target soon.

DAY 1 CONVECTIVE OUTLOOK CORR 1

NWS STORM PREDICTION CENTER NORMAN OK

0106 AM CDT WED MAY 19 2010

VALID 191200Z - 201200Z

...THERE IS A MDT RISK OF SVR TSTMS ACROSS MUCH OF OKLAHOMA AND

ADJACENT PARTS OF NORTH TEXAS AND WESTERN ARKANSAS...

...THERE IS A SLGT RISK OF SVR TSTMS FROM SOUTHWEST KANSAS TO

NORTHERN TEXAS...PARTS OF SOUTHWEST ARKANSAS AND NORTHERN

LOUISIANA...

ADDED APPROXIMATE INITIATION TIME IN 4TH PARAGRAPH.

...SYNOPSIS...

A POTENTIALLY SIGNIFICANT SEVERE WEATHER OUTBREAK APPEARS

INCREASINGLY LIKELY ACROSS PARTS OF OKLAHOMA...SOUTHERN KANSAS...AND

NORTHERN TEXAS LATER TODAY. STRONG TO SEVERE STORMS WILL ALSO BE

POSSIBLE SOUTH AND EAST FROM THESE AREAS...FROM ARKANSAS TO

LOUISIANA.

...SRN PLAINS INTO ARKLATEX...

A LARGE DEEP-LAYER CYCLONE WILL EVOLVE ACROSS CO/WY EARLY TODAY AND

THEN DRIFT EAST ACROSS THE CENTRAL PLAINS STATES THROUGH TONIGHT.

WIDESPREAD THUNDERSTORMS WERE ALREADY OCCURRING AHEAD OF THIS

DEVELOPING LOW AS WARM ADVECTION AND LARGE SCALE ASCENT ACT ON A

MOIST AND MODERATELY UNSTABLE AIR MASS FROM TX TO KS. PRECIPITATION

AND RESIDUAL CLOUDINESS FROM THE STORMS NOW DEVELOPING ACROSS NRN OK

AND KS WILL ACT TO ESTABLISH A NW-SE ORIENTED WARM FRONT ACROSS OK

LATER THIS MORNING.

AS THE UPPER LOW EMERGES OVER WRN KS LATER THIS AFTERNOON... TRIPLE

POINT SURFACE LOW IS FORECAST TO STRENGTHEN INVOF OK PANHANDLE AS

DRYLINE SHARPENS AND SPREADS EAST FROM ERN TX PANHANDLE. BELT OF

40-50KT WLY CYCLONIC MID LEVEL FLOW ATOP SLY/SELY LOW LEVEL FLOW

ACROSS THE WARM SECTOR WILL CONTRIBUTE TO STRONG EFFECTIVE SHEAR AOA

40KT. DIURNAL HEATING AND GRADUAL MOISTENING OF THE BOUNDARY LAYER

SHOULD RESULT IN AN INCREASINGLY UNSTABLE WARM SECTOR WITH WEAKLY

CAPPED MLCAPE OF 1500-2000 J PER KG BY AFTERNOON.

GIVEN WEAK INHIBITION AND PERSISTENT MODEST FORCING FOR ASCENT

EXPECT WARM SECTOR STORM INITIATION BY 21Z. DISCRETE SUPERCELLS

SHOULD EVOLVE QUICKLY AHEAD OF THE DRY LINE IN WRN OK...WITH

ADDITIONAL STORMS POSSIBLE NEAR/ALONG RESIDUAL OUTFLOWS AND NEAR

SURFACE WARM FRONT...FROM NRN/CNTRL OK TO NRN TX/AR/LA. EFFECTIVE

HELICITY IN THE RANGE OF 200-300 M2/S2...AND RELATIVELY HIGH

BOUNDARY LAYER RH/LOW LFC ACROSS CNTRL OK...SHOULD RESULT IN AN

ENHANCED STRONG TORNADO POTENTIAL ACROSS THIS AREA FROM LATE

AFTERNOON INTO EARLY EVENING.

UNLIKE MAY 10...WEAKER FLOW REGIME RESULTS IN SLOWER STORM/BUNKERS

CELL MOTION OF ENE AROUND 25 KT...AS OPPOSED TO ENE AT 50KT.

FURTHERMORE...INSTABILITY APPEARS A BIT WEAKER. NONETHELESS...A

POTENTIALLY VOLATILE STRONG TORNADO SITUATION MAY EVOLVE ACROSS

PORTIONS OF CNTRL OK DURING THE AFTERNOON...POSSIBLY MOVING TOWARD

ERN OK INTO THE EVENING. THIS IS A RELATIVELY LIMITED GEOGRAPHIC

AREA OF GREATER TORNADO POTENTIAL. COMBINED WITH THE POSSIBILITY

THAT FORECAST CERTAINTY CAN INCREASE WITH THE LIGHT OF DAY...GREATER

TORNADO PROBABILITIES...AND AN UPGRADE TO HIGH RISK...MAY OCCUR IN

SUBSEQUENT OUTLOOKS.

IN ADDITION TO THE TORNADO POTENTIAL...VERY LARGE HAIL AND LOCALLY

DAMAGING DOWNBURST/OUTFLOW WINDS WILL ACCOMPANY STORM DEVELOPMENT

ACROSS A LARGER AREA FROM SRN KS EXTENDING INTO TX...AR AND LA FROM

AFTERNOON THROUGH THE EVENING.

AS CONVECTION CONGEALS OVER ERN OK THROUGH THE EVENING...LIFT AND

SUSTAINED INSTABILITY ACROSS THE WARM FRONT...AND UPSCALE EVOLUTION

IN STRONGLY SHEARED FLOW...WILL CONTRIBUTE TO FORWARD PROPAGATING

MCS/SQUALL LINE WITH DAMAGING WINDS SPREADING SEWD TOWARD AR AND THE

ARKLATEX THROUGH THURSDAY MORNING.

[nsrobins]

Posted on UKWW in the last hour:

Interestingly the DL is a bit more diffuse than recent days but the CIN is low to non-existant across SW OK. A very stout 45-50kn H500 wind from the WSW overides an increasing (30kn range) LLJ from the SSE, so any cell initiating in the 3500 or so max cape available will move at 25mph into this highly sheared environment. If I was to target anywhere it would be in the western side of the MOD risk area somewhere SW of OKC and expect quite early initiation.

Target - Lawton, OK

I also add that should the SW directed outflow boundary line-up with a weak warm frontal zone across the south of OK, and should a cell latch on to this boudary, it may go ballistic.

[Nick F]

I think I would target Altus-Lawton, OK area too. Unfortunately my normal point of access for charts, from Nexlab/College of Du Page has out of date charts - because their site has been down this morning, so relying on Oscar Van der Velde's lightning wizard charts (based on 06z GFS run) for N America, but they show strong tornado potential over central/central Sern Oklahoma - looking at CAPE, DLS/LLS and SR Helicity - highlighted by his significant tornado parameters:

Triple point looks likely to move across S-central OK this evening, which will enhance wind shear and lift over the area and thus strong storms with potential to drop tornadoes:

[dallas]

Local news from Wichita says to look out for discrete supercells during the early part of the outbreak (1400 - 1700) local time, should be some large to v.large hail with the chance of strong tornados.

Good chasing fun ahead!

[Harry]

Best of luck chaps!! I wish I could open a wormhole and zip across....miss that place so much!!!

[Stuart]

Good luck team 3

[Nick F]

Gone HIGH RISK on the 1630z update over Oklahoma, what a May this is turning out to be! OK City in the firing line for perhaps a strong tornado again unfortunately. Going to be bedlam out there with 30% prob of a tornado withing 25 miles of a point over central Oklahoma.

DAY 1 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

1130 AM CDT WED MAY 19 2010

VALID 191630Z - 201200Z

...THERE IS A HIGH RISK OF SVR TSTMS OVER PARTS OF CNTRL OK...

...THERE IS A MDT RISK OF SVR TSTMS SURROUNDING THE HIGH RISK AREA

OVER A LARGE PART OF OK AND N TX...

...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK

AREA...FROM SW KS INTO THE LWR MS VLY...

...SIGNIFICANT SVR TSTM OUTBREAK EXPECTED THIS AFTN THROUGH TONIGHT

FOR A LARGE PART OF OK AND ADJACENT N TX...

...SYNOPSIS...

NE CO UPR LOW WILL MOVE SLOWLY E INTO CNTRL KS BY 12Z THU AS

ASSOCIATED SHORTWAVE TROUGH NOW EXTENDING SSW INTO NM SWEEPS E INTO

CNTRL OK/N CNTRL TX. BAND OF SEASONABLY STRONG CYCLONIC WSW FLOW ON

S SIDE OF LOW WILL PERSIST OVER THE SRN PLNS...ATOP MODERATE SSWLY

LLJ. MAIN SYNOPTIC FRONTAL ZONE EXTENDING SE FROM TX PANHANDLE SFC

LOW SHOULD EDGE SLOWLY NE THROUGH THE PERIOD... WITH MOVEMENT OFFSET

BY CONVECTIVE OUTFLOW. S OF THE FRONT AND E OF LEE TROUGH/DRY LINE

OVER THE ERN PANHANDLE...LOW LVL MOISTURE WILL CONTINUE TO SPREAD

NWD WITH LLJ.

...SRN PLNS/ARKLATEX THROUGH EARLY WED...

OVERNIGHT OK MCS SHOULD FURTHER WEAKEN AS CONTINUES GENERALLY ESE

INTO NW AR EARLY THIS AFTN. ELEVATED STORMS...A FEW OF WHICH MAY BE

ACCOMPANIED BY HAIL...LIKELY WILL PERSIST THROUGH THE DAY ATOP W/E

OUTFLOW BOUNDARY LEFT BY THE MCS.

BY MID TO LATE AFTN...COMBINATION OF SFC HEATING...CONTINUED LOW LVL

MOISTURE INFLOW...AND LEADING EDGE OF ASCENT WITH NM UPR TROUGH

EXPECTED TO SUPPORT NEW SFC-BASED STORMS NEAR INTERSECTION OF

OUTFLOW BOUNDARY WITH EWD-MOVING LEE TROUGH/DRY LINE OVER WRN OK. A

BIT LATER...SCTD DEVELOPMENT SHOULD EXTEND SWD ON THE TROUGH/DRY

LINE INTO NW TX...AND EWD ALONG OUTFLOW BOUNDARY INTO CNTRL OK.

THE STORMS WILL QUICKLY BECOME SUPERCELLS GIVEN 40-50 KT DEEP WSWLY

SHEAR AND SBCAPE OF 2500-3000 J/KG. THE SETUP APPEARS MOST

FAVORABLE FOR LARGE...RELATIVELY SLOW MOVING INTENSE STORMS WITH

LARGE HAIL. GIVEN SIZABLE LOW LVL DIRECTIONAL COMPONENT TO

SHEAR...ESPECIALLY NEAR REMNANT OUTFLOW BOUNDARY AND/OR FRONT...A

COUPLE STRONG TORNADOES ALSO MAY OCCUR.

WITH THE LLJ LIKELY TO STRENGTHEN AND VEER DUE TO DIURNAL INFLUENCES

AND THE CONTINUED EWD MOVEMENT OF NM TROUGH...EXPECT THE OK/N TX

STORMS TO EVOLVE INTO A LARGE MCS EARLY TONIGHT. COUPLED WITH

INCREASINGLY DIFLUENT HI LVL FLOW...THIS SYSTEM SHOULD CONTINUE ESE

INTO AR BY EARLY WED...WITH AN ATTENDANT THREAT FOR DMGG WIND/HAIL

AND VERY HEAVY RAIN.

...ARKLATEX TO CNTRL GULF CST THIS AFTN...

SFC HEATING ALONG/S AFOREMENTIONED SYNOPTIC FRONT EXTENDING SE FROM

SRN PLNS LOW MAY SUPPORT SCTD DIURNAL STORMS FROM THE ARKLATEX SE TO

THE CNTRL GULF CST TODAY. THIS ACTIVITY WILL BE CONDITIONAL ON

HEATING AND LOW LVL CONVERGENCE BECOMING LOCALLY SUFFICIENT TO

OVERCOME WEAK CIN OVER REGION. AMPLE INSTABILITY/ PW WILL BE

PRESENT FOR STRONG UPDRAFTS AND PERHAPS ISOLD SVR WIND GUSTS/HAIL.

BUT WEAK SHEAR SHOULD LIMIT STORM ORGANIZATION/ PERSISTENCE.

..CORFIDI/HURLBUT.. 05/19/2010

[NL]

First MD out from NWS/SPC.

MESOSCALE DISCUSSION 0623

NWS STORM PREDICTION CENTER NORMAN OK

0122 PM CDT WED MAY 19 2010

AREAS AFFECTED...OK AND EXTREME NRN TX

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 191822Z - 192015Z

MID-LVL SHORTWAVE RIDGING IN WAKE OF THE MORNING MCS WAS BEGINNING

TO MIGRATE INTO ERN OK AND ACCELERATED COOLING ALOFT IS EXPECTED TO

SPREAD EWD THROUGH THE NEXT FEW HOURS. 18Z VSBL SATL ALREADY SHOWS

EVIDENCE OF TCU INVOF THE TRIPLE POINT OVER ERN HEMPHILL/WHEELER

COUNTIES IN THE TX PNHDL AND MAY MARK THE BEGINNING OF AN ACTIVE

MID-LATE AFTN/EVENING DOWNSTREAM.

18Z MESOANALYSIS DEPICTS AN OUTFLOW BOUNDARY VERY NEAR I-40 WITH A

WRMFNT EXTENDING ESE FROM THE TRIPLE POINT ACROSS NORMAN TO SERN OK.

A PRE-FRONTAL TROUGH SEEMINGLY HAS EVOLVED AND WAS LOCATED A COUPLE

ROWS OF COUNTIES W OF I-44...WELL-AHEAD OF THE DRYLINE. TO THE W OF

THIS FEATURE...CU FIELD WAS INCREASING AND STRATUS WAS ERODING TO

THE N OF THE OUTFLOW BOUNDARY FROM ABOUT EL RENO WWD TO THE STATE

LINE.

AS THE SFC LOW BEGINS TO DEEPEN THIS AFTN...EXPECT THAT THE SFC-H85

FLOW WILL BACK SOMEWHAT AND MAINTAIN SUFFICIENT CONVERGENCE ALONG

THE DRYLINE TO SUPPORT TSTM INITIATION IN THE 19-21Z TIME

FRAME...PERHAPS EVOLVING FROM CURRENT BUILD-UPS ENTERING WCNTRL OK.

OTHER STORMS MAY ALSO INITIATE EWD ALONG THE OUTFLOW OR EVEN PERHAPS

THE PRE-FRONTAL TROUGH FROM OKC METRO WWD ALONG/JUST N OF I-40 AFTER

21Z. MATURE STORMS WILL TRACK ROUGHLY 250/30 KTS.

INGREDIENTS ARE BEGINNING TO CONGEAL FOR THE POSSIBILITY OF STRONG

TORNADOES FROM N OF KCSM ESE THROUGH KOKC METRO IN THE 21Z-02Z AND

POSSIBLY FARTHER ESE INTO ECNTRL OK BY MID-EVENING. HERE...0-1KM

SRH WILL GENERALLY BE 250-300 M2/S2 AMIDST LOW LCL/S AND A HIGH

PROBABILITY FOR DISCRETE STORMS. OTHERWISE...VERY LARGE HAIL AND

DMGG WIND GUSTS CAN ALSO BE EXPECTED.

..RACY.. 05/19/2010

[kold weather]

Yep a High Risk once again (this has gotta be one of the most active monthly periods for a few years now!) which isn't that surprising, conditions are very impressive, though maybe not quite as extreme as other high risk events recently.

Still have fun chasing tonight guys, I'd be fully expecting some decent tornadoes tonight, Helicity looks very good for today guys so good luck!

[NL]

Thought it wouldn't be long... Tornado watch PDS

937

WWUS20 KWNS 191913

SEL0

SPC WW 191913

OKZ000-200300-

URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 190

NWS STORM PREDICTION CENTER NORMAN OK

205 PM CDT WED MAY 19 2010

THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF

MUCH OF OKLAHOMA

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 205 PM UNTIL

1000 PM CDT.

..THIS IS A PARTICULARLY DANGEROUS SITUATION

DESTRUCTIVE TORNADOES...LARGE HAIL TO 3.5 INCHES IN DIAMETER...

THUNDERSTORM WIND GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE

POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 40 MILES SOUTH OF GAGE

OKLAHOMA TO 40 MILES EAST SOUTHEAST OF MCALESTER OKLAHOMA. 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...TSTMS EXPECTED TO FORM IN THE NEXT HOUR OR SO INVOF

SLOWLY RETREATING W/E OUTFLOW BOUNDARY IN W CNTRL OK. OTHER STORMS

ALSO MAY FORM A BIT LATER NEAR INTERSECTION OF OUTFLOW BOUNDARY WITH

CONFLUENCE LINE IN CNTRL OK...AND IN MORE STRONGLY HEATED

ENVIRONMENT NEAR WARM FRONT IN SE OK /REF MCD 623/.

GIVEN STRENGTH OF WIND FIELD...EXPECTATION OF CONTINUED LOW LVL

DESTABILIZATION...AND EVENTUAL ONSET OF MID LVL COOLING/ASCENT WITH

UPR IMPULSE NOW IN THE WRN TX PANHANDLE...SETUP APPEARS FAVORABLE

FOR THE DEVELOPMENT OF STRONG SUPERCELLS. ONE OR TWO OF THESE MAY

BECOME LONG-LIVED...AND YIELD A COUPLE STRONG TORNADOES...AS THEY

INTERACT WITH BACKED LOW LVL FLOW NEAR OUTFLOW BOUNDARY AND/OR WARM

FRONT.

Just to add... These are the probabilities that NWS/SPC have given for todays/tonights severe event.

WWUS40 KWNS 191913

WWP0

TORNADO WATCH PROBABILITIES FOR WT 0190

NWS STORM PREDICTION CENTER NORMAN OK

0213 PM CDT WED MAY 19 2010

WT 0190 PDS

PROBABILITY TABLE:

PROB OF 2 OR MORE TORNADOES : >95%

PROB OF 1 OR MORE STRONG /F2-F5/ TORNADOES : 60%

PROB OF 10 OR MORE SEVERE WIND EVENTS : 80%

PROB OF 1 OR MORE WIND EVENTS >= 65 KNOTS : 30%

PROB OF 10 OR MORE SEVERE HAIL EVENTS : >95%

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/ : 60

MAX TOPS /X 100 FEET/ : 550

MEAN STORM MOTION VECTOR /DEGREES AND KNOTS/ : 26030

PARTICULARLY DANGEROUS SITUATION : YES

Edited May 19, 2010 by NL

[Nick F]

Looking at the hourly meso analysis draws me to just SW of OK City area - somewhere like Chickasha for best dynamics for strong tornadoes should a supercell develop/move into the area:

Very juicy air now advecting from SE into southern and central OK, Td of 67F at OKC and Td of 70F at Ardmore:

Largest SBCAPE values towards S and SW OK:

Best 0-1km and 0-3km SR Helicity values towards central, N and NE Oklahoma:

Overlap CAPE and SR Helicity and you'll probably be looking at a swath of south to west central OK seeing best potential for tornadoes right now as shown by significant tornado parameter - this shifting north as surface instability/SBCAPE increases further north as warm front lifts north over OK:

A few isolated cells popping up over far western Oklahoma along the cold front atm.

[A.J]

Storms now firing up over Western Oklahoma on Intellicast doppler.. Link

[Nick F]

Yep, storms over far western OK appear to be firing along cold front:

further east, but mainly west of the I-44 from Lawton up to OK City - appears to be a healthy cu field developing in sunshine, further E and SE more in the way of high cloud, and over northern OK into KS plenty of stratus which may hamper convection.

[NL]

Latest MD update.

MESOSCALE DISCUSSION 0624

NWS STORM PREDICTION CENTER NORMAN OK

0320 PM CDT WED MAY 19 2010

AREAS AFFECTED...OK

CONCERNING...TORNADO WATCH 190...

VALID 192020Z - 192145Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 190 CONTINUES.

20Z MESOANALYSIS PLACES A LOW JUST S OF KGAG WITH A WRMFNT ESE

ACROSS DEWEY...BLAINE...KINGFISHER...OKLAHOMA COUNTIES...THEN SEWD

TO CHOCTAW COUNTY. A DRYLINE EXTENDED S FROM THE LOW INTO THE ALTUS

AREA.

TSTMS WERE INCREASING OVER WCNTRL OK NEAR THE TRIPLE POINT AND WILL

LIKELY BUILD SWD ALONG THE DRYLINE THROUGH LATE AFTN. OTHER STORMS

WILL CONTINUE TO GROW ALONG THE WRMFNT FROM JUST W OF KOKC WNW INTO

BLAINE/MAJOR COUNTIES. YET A THIRD REGION OF INITIATION...PER

LATEST RAPID REFRESH AND RECENT TCU DEVELOPMENT...WILL BE ACROSS

SERN OK TO THE SW THROUGH NW OF KMLC ALONG A POSSIBLE GRAVITY WAVE.

AS STORMS MATURE INTO SUPERCELLS THEY WILL MOVE 250/30 KTS WITH THE

TORNADO THREAT MAXIMIZED INVOF THE WRMFNT...PARTICULARLY FROM

KINGFISHER ESE THROUGH OKC METRO AND INTO SE OK NEAR KMLC. THIS

ZONE WILL MAINTAIN ESELY LLVL FLOW VEERING QUICKLY TO SW ABOVE 2-3

KM AMIDST LOW LCLS. VERY LARGE HAIL CAN ALSO BE EXPECTED.

[NL]

Storms can be followed live here on KOCO..

http://www.koco.com/video/23509261/index.html

[Nick F]

Nice tail cloud on that storm near Hennessey, all waiting for it drop from its large wall cloud.

Hopefully storms will pop up further south for the team now heading west of the I-35 towards Duncan and maybe Lawton. Plenty of Tcu on the livestream.

[Nick F]

Storm W of Hennessey produced a brief funnel from the wall cloud:

Storm further west looks interesting from reflectivity too.

[Nick F]

Looks like a storm popping up over the Ouachita Mountains NW of Lawton, west of the team's current location.

Huge wall cloud on the Hennessey storm, still waiting for the nado!

Wrapping rain curtains now, nado on the way!?

[Paul Sherman]

Its Arron here posting for Paul and the rest of the team. Just heading west towards the cell thats fired NW of Lawton. Tops look ace! :blush:

[NL]

Large, large tornado on the ground now. Chopper feed is outstanding..!!

[Nick F]

Holy crap, lovely stove pipe tornado on the ground near Hennessey:

Lifted up and cycling now.

Back on the ground ...

... and back up again.

[nsrobins]

Awesome couplet on the Marshall storm - +65/-65 shear in there.

Also watch those DL cells near Lawton - they could explode.

[Nick F]

Sounds very ominous the circulation near Orlando now, watch out i-35, hard chasing it though as it's HP and any tornado likely to be rain-wrapped. That wall cloud hugging the ground in the supercell further west heading for Dover and Kingfisher looking ominous now too!

Storms seem to be struggling atm N and NE of Lawton along dryline, still not severe-warned yet, though may turn supercellular anytime with potential to form strong tornadoes. The team may find these easier to chase compared to the HP beasts with rain-wrapped nados along the warm front further north

[nsrobins]

Really worried for Stillwater - huge tightening circulation 10 mins away.

[Nick F]

Good news for the team, storm near Chickasha getting its act together in last half hour with possible circulation developing on it, though still high-based by the sounds of it.