CHASE CASE 14

[Kurt Hulst]

Watching the CU develope along the OFB i am currently in Woodward, was thinking about headed NW to Rosston, OK. But as of now I will hold up in Woodward at the Days INN on the NW side of town.

 

[Jim Tang]

Am I the only one who sees the likelihood of significant capping issues in TX/OK/srn KS? According to DDC and AMA 18Z soundings, convective temps are soaring to over 30C, 850's near the critical threshold of 24C, 700's near the critical threshold of 12C... either I can't read a sounding or that's not going to support rigorous thunderstorm development (and even if a storm were to somehow breach the cap, there would be high base issues).

I'm blasting north, conservatively to Ness City, KS. The triple point (quadruple point if one includes the OFB) to the north calls me. Hopefully I won't make the dumbest decision of the year lol, the CU field at 19Z in SW KS forced me to think hard about my decision.

 

[Josh Richardson]

Slowly drifting west out of Woodward on 270 towards the Beaver OK area, well I guess there is nothing to do there so I might get kind of bored. Hey Dustin, lets meet up and play some catch!!

 

[Paul Austin]

19z

19z:

Am I the only one who sees the likelihood of significant capping issues in TX/OK/srn KS? According to DDC and AMA 18Z soundings, convective temps are soaring to over 30C, 850's near the critical threshold of 24C, 700's near the critical threshold of 12C... either I can't read a sounding or that's not going to support rigorous thunderstorm development (and even if a storm were to somehow breach the cap, there would be high base issues)....

No, you're not the only one. I have serious concerns about the mega-cap. I am banking (probably in vain) on sfc convergence and boundary lift to weaken the cap. Wishfully, a sounding out of Woodward or Liberal would look a little better wrt the capping issue. I'm encouraged to see some cu building just nw of my location.

That said, nw/nc KS looks better and better. Congestus along the NE border indicates there is certainly no capping issue up there, and the lifting boundary/OFB intersection seems to be kick-starting some action. But I'm gonna hang here and hope for something a little more discrete. I'll stay here in Elmwood, OK for now. If I left now, I could make Hill City by 23z, but I'll stick to plan despite the bust potential.

 

[John Erwin]

Sitting here in Liberal, KS with a crapload of sunblock on and getting twitchy. I'm still thinking this is a great area to be in; buckets of moisture and a prominent DL bulge, although I can't help but think the wind may not provide enough shear, however there are other factors.

I have a feeling I'll either be heading NE or SE from here after I see the 21Z data or something before then, however this location provides a great launch for either direction.

 

[Dick McGowan]

Looks like some agitated cu just to my south (Garden City, KS). However, after much thought, I'm flying north to Quinter, KS and should be there in 2 hours or less (by 20z). There's an outflow boundary that is drifting SW and initiation looks underway near this triple point...and I want to be there when a storm interacts with it. I can always drop back south and storm-hop any storm that fires in SW Kansas later. Hope I don't drop the ball on this one.

 

[Brian Stertz]

It's a late May or early June type event so I'll bank on the cap not being as big of a factor as typical. Texas Panhandle is very notorious in these very situations ...and if nothing goes I can jump on any stuff that happens to get going in SW Kansas on the boundary/DL intersection. Hanging tough in Perryton TX.

 

[John Farley]

Based on the 15Z data, I moved north to Arnett, OK. When I saw the 18Z data, I poked a little farther north to Gage, OK where I will sit and wait to see what develops. I like the more backed surface wind in that area, and the clearing over the TX panhandle just to the SW of this area. I am resisting the temptation to go after the stuff firing farther east along the OFB; I think that, assuming we get storms in the Gage/Arnett/Woodward area, the potential for tornadoes will be greater due to better directional shear.

 

[Marc Austin]

19z:


No, you're not the only one. I have serious concerns about the mega-cap. I am banking (probably in vain) on sfc convergence and boundary lift to weaken the cap. Wishfully, a sounding out of Woodward or Liberal would look a little better wrt the capping issue. I'm encouraged to see some cu building just nw of my location.

That said, nw/nc KS looks better and better. Congestus along the NE border indicates there is certainly no capping issue up there, and the lifting boundary/OFB intersection seems to be kick-starting some action. But I'm gonna hang here and hope for something a little more discrete. I'll stay here in Elmwood, OK for now. If I left now, I could make Hill City by 23z, but I'll stick to plan despite the bust potential.

Ok Paul, I'll tag along with you down in Elmwood, OK. If it were up to me, I might head back up toward Liberal, KS just in case we want to catch anything that pops up in W KS. I think that outflow boundary may interact with the dryline here in a couple of hours and give us a nice line of sups. The only question, how strong will the cap be and how far south will the storms extend? Hopefully to the OK border. We'll wait here and see.

 

[Leah Robertson]

Whoa, I'm really far behind in the updates...

*Looks at the 15Z data*
The outflow boundary across SW Kansas still looks as sharp as ever and the surface obs are showing a nice moisture axis trying to creep up into this region. I'm also curious to see exactly how the dryline is going to behave and will compare the 15Z obs with the 18Z obs. For now, I'm going to have a nice cup of tea with an ol' college friend and stay in Cimarron, Ks.

*Looks at the 18Z data*
Immediately noticed the bulge in the dryline across the TX panhandle which certainly could be a contender for initiation later on today. The dryline appears to be sharpening up noted by the temp/DP depression, particularly across the NW Texas panhandle. As the low continues to move across the region, this should help the moisture axis to progress further northward. The DDC sounding continues to show a decent lapse rate with the winds semi-veering with height. Going to go ahead and sneak on down into an area where there is a little bit more moisture but not too far from the triple point so I'm moving from Cimarron, KS and head SE to Minneola, KS

*Looks at 19Z data*
Noticed the TCU to the west and will hold my position in Minneola, KS until the next update....

 

[Dennis Dennison]

I have had cells overhead here in Fayettville all day, I like the stuff forming in OK..I think I am going to move westward towards I35/421 intersection and monitor for more details

 

[Andrea Griffa]

I'm taking a look at DDC-Liberal,Ks zones and I like'em so much, overall that pretty nice bulge in the dryline. Let's see what will it be.
For now, I will stay put in DDC till the next run.

 

[Patrick Martin]

18z update

I suspect I've missed an update or 2 since I last saw, so playing some catch up a bit. To keep me honest, will start with the 18z, and then edit to add content as I move forward through the case.

18z - In Garden City KS and am going to hold position for now. Have backed winds and decent moisture at my location and with a dryline bulge punching ne'wrd through the TX panhandle, think it will help to initiate things later on. Will closely monitor things though as I may need to adjust eastward a bit. Have gassed up the car and ready to move at a moments notice.

19z- Been sitting in the sun in Garen City, got antsy, and drifted eastward on hwy 156 to Jetmore, KS. Still eyeing the dryline bulge to my SW, but with a surging boundry backing into NW KS and associated cu field, have opted to take my chances and move up hwy 283 to Ness City, KS, although further north may be necessary.

 

[Matt Gingery]

20Z SUPPLEMENTAL UPDATE​

SATELLITE​

CENTRAL PLAINS: http://i41.tinypic.com/2q8r6ab.jpg

SOUTHERN PLAINS: http://i40.tinypic.com/euiluo.jpg

UPPER MIDWEST: http://i40.tinypic.com/73ig09.jpg

MID MISSISSIPPI: http://i40.tinypic.com/f25tp1.jpg

RADAR COMPOSITE​

CENTRAL PLAINS: http://i39.tinypic.com/29y3yqh.gif

SOUTHERN PLAINS: http://i42.tinypic.com/24e137d.gif

UPPER MISSISSIPPI: http://i44.tinypic.com/t0m3rm.gif

MESOSCALE DISCUSSION​

MD #4 http://i42.tinypic.com/20062vo.gif

MESOSCALE DISCUSSION
NWS STORM PREDICTION CENTER NORMAN OK
0235 PM CDT

AREAS AFFECTED...NRN/CENTRAL LOWER MI WWD INTO ERN WI

CONCERNING...SEVERE THUNDERSTORM POTENTIAL



TSTMS DEVELOPING OVER NRN LOWER MI ALONG LAKE BREEZE CONVERGENCE
ZONE MAY BEGIN TO PRODUCE LARGE HAIL/DAMAGING WINDS IN THE NEXT 1-2
HOURS. THERE IS ALSO SOME CHANCE THAT ISOLATED SVR STORMS MAY
DEVELOP OVER ERN WI/PORTIONS OF WCENTRAL/NWRN LOWER MI IN THE SAME
TIME FRAME.

WELL DEFINED MCV OVER ERN IA WILL CONTINUE TO MOVE NEWD INTO WI
THROUGH THE REMAINDER OF THE AFTERNOON. BLR PROFILER SHOWS MID LEVEL
SWLY FLOW HAVE INCREASED TO AROUND 40 KTS. APX VWP DATA SHOWS 5 KM
WINDS HAVE INCREASED TO 30 KTS. MODEST MID LEVEL FLOW/DEEP LAYER
SHEAR AROUND 30-35 KTS OVER THE AREA...COMBINED WITH ALREADY
MODERATELY UNSTABLE AIRMASS WITH MLCAPES AROUND 2500 J/KG WILL
SUPPORT AT LEAST AN ISOLATED SVR THREAT THROUGH THE AFTERNOON OVER
NRN/CENTRAL LOWER MI.

FARTHER WEST OVER ERN WI IF THE CIRRUS SHIELD DOES NOT ADVANCE TOO
RAPIDLY EAST THROUGH 21Z...SUFFICIENT DEEP LAYER SHEAR WOULD BE
PRESENT FOR AN ADDITIONAL ISOLATED LARGE HAIL/DAMAGING WIND THREAT.
HOWEVER...THIS WILL BE THE CASE ONLY IF REMAINING CINH IS REMOVED
AND STORMS DEVELOP IN THE NEXT 1-2 HOURS BEFORE THICKER CIRRUS
CLOUDS OVERSPREAD THIS AREA.

MD #5 http://i44.tinypic.com/24yy3jc.gif


MESOSCALE DISCUSSION
NWS STORM PREDICTION CENTER NORMAN OK
0243 PM CDT

AREAS AFFECTED...EXTREME SERN NM THROUGH W TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID

SERN NM THROUGH PARTS OF WRN TX ARE BEING MONITORED FOR THUNDERSTORM
INITIATION. IF STORMS DEVELOP...SUPERCELLS WITH VERY LARGE HAIL WILL
BE LIKELY. ISOLATED TORNADOES MAY ALSO BE POSSIBLE. IF TRENDS BEGIN
TO SUGGEST INITIATION IS IMMINENT...A WW WILL BE NEEDED FOR PORTIONS
OF THIS AREA.

DRYLINE EXTENDS FROM THE TX PANHANDLE JUST W OF AMARILLO SWWD INTO
EXTREME SERN NM THEN SWD TO JUST E OF FORT STOCKTON. THE ATMOSPHERE
HAS BECOME VERY UNSTABLE E OF THIS BOUNDARY. DEWPOINTS IN THE UPPER
60S UNDERNEATH STEEP LAPSE RATES IN CONJUNCTION WITH STRONG SURFACE
HEATING HAS CONTRIBUTED TO MLCAPE FROM 3500 TO 4000 J/KG. LATEST
VISIBLE IMAGERY SHOWS CUMULUS DEVELOPING IN VICINITY OF AND W OF THE
DRYLINE WHERE DEEP MIXING IS OCCURRING. ONCE STORMS DEVELOP...THEY
SHOULD MOVE EWD AND INTENSIFY AS THEY INTERCEPT THE STRONGER
INSTABILITY. THE 0-6 KM SHEAR ON THE ORDER OF 35 TO 40 KT AND
MODERATE WLY MID LEVEL FLOW WILL SUPPORT SUPERCELLS. THE LOW LEVEL
FLOW AND SHEAR ARE RELATIVELY WEAK...BUT GIVEN SHEAR THROUGH A
DEEPER LAYER SUPPORTIVE OF SUPERCELLS AND THE PRESENCE OF STRONG
INSTABILITY...POTENTIAL FOR ISOLATED TORNADOES MAY ALSO EXIST.

 

[Andrea Griffa]

Ok,by the 20Z update I see there's a new isolated cell developing just over here in DDC along the NE part of the bulge. Let's see what happens: the sky is pretty dark and it seems to me to see a lowering in the distance.