Chase Case #10

[Matt Gingery]

I think you're talking about the upper diffluence over the area, not divergence (I assume when you say "the area" you are speaking of Coldwater - there is diffluence over Coldwater and divergence over Elk City)...two different things. I'm not picking on you, but I've noticed a lot of people during the chase cases mistaking divergence for diffluence and vice versa. This is a good start for learning to differentiate the difference between the two...

http://www.theweatherprediction.com/advanced/habyextra6/

Quick question in regards to Diffluence, and Divergence. Both related to the Rosby Wave aloft. Aren't the two of these co-related? I mean, you cannot have Diffluence without Divergence aloft. Isn't Diffluence just rising air horizontally in relation to Divergence aloft, more or less just a fancy word for Convection. Anyway, I definately know it isn't Confluence across the region, or there would be no convection. Isn't it just a formality? Please go into more detail because I am very interested in a synoptic definition of this type of event to where it makes more sense to me as well. Thanks. . .


Anyway, I beamed myself to Lubbock Tx and am ready for the next update. As far as OFB's are concerned they spread in all directions, so I am sure I can locate one close by as destabilization occurs. As of the 15z update, winds are backed nicely across the Tx Panhandle. Cells across Oklahoma look like mainly hail and wind threat, maybe some rain wrapped stuff. I imagine around 18-21z it will light up from Goodland to Midland. Good Luck to everyone!!!!

 

[Dann Cianca]

I'm holding steady in Glasgow, Montana. Like that patch of clear skies to the south that will move up. It will probably mix us down a bit, that's alright. The southeasterly surface winds will keep the juice flowing.

 

[Michael P. Morris]

I'm about 45 minutes out of Amarillo right now, having left Norman at about 800 AM. I still think Amarillo is the place to be, as the 500 mb ridge has progressed off to the east, but the shortwave appears to be ejecting a little further south based on the profiler data. Additionally, instability appears to be increasing under the clearing skies to the south (Lubbock-Midland region). I will likely sit tight somewhere in Amarillo and make a final decision then.

I expect an earlier initiation given the timing of the upper-level support, so I will probably be limited to a 2 hour driving window from Amarillo to get in place, so anywhere between Guymon and Lubbock is fair game.

 

[Paul Austin]

12z/15z

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I'm veering towards Lubbock as a start location also. I have never chased successfully in Eastern Texas so this will be an interesting one to follow....

I assume you meant West Texas?
[FONT=&quot]
12z:[/FONT]

I'll set up shop initially near Canadian, TX. I'm not loving the morning convection, but there are some breaks in the clouds and at least I'm free of heavy precip.
Pros:

• backed sfc winds, but that is likely to change with later LLJ and development of any OFB's
• strong southerly 850mb winds for moisture transport and directional wind shear
• mid-60's Td's
• approaching short wave
• ability to get up n into KS or w toward NM should developments warrant

Cons:

• morning convection and precip
• messy cold pool interactions
• canopy overhead limiting sfc heating
• out of position for any play n of KS

I see some possibility for a few n plains cells as well, but I’m gonna stay s on this one. I really like the sounding out of OUN, not so much out of AMA and MAF attm, but mid/upper level winds should bring in cooler temps aloft. Hopefully Canadian puts me within striking distance of whatever develops.

[FONT=&quot]15z:[/FONT]

Interesting development. Yes, I like the OUN sounding, and the vertical wind profile from w to c OK is favorable for rotation, but I’m not sure I want to bite on anything this early and lose position for any panhandle magic on its way. The isolated cells in extreme nw TX pan look promising with plenty of surrounding sunshine and position along what appears to be an e-w oriented OFB. Td’s w of the NM border in the 20’s gives me hope for some action a little later along the dry line. I think I’ll take my chances with the cap and move toward the developing cells with an eye both southward and north along that boundary. I’ll head toward Amarillo, TX (ETA: 17z), with an eye toward the cell nw of me. Depending on storm motion and what I can see, I’ll try to decide whether or not to make an intercept.

 

[Kurt Hulst]

After Looking at the 12z and seeing some nice OFB's and clearing starting to take place I will start this one in Liberal, KS. See ya in a few Dick.

15z: Looking at the latest I think I will hold here in Liberal.

 

[Marc Austin]

12Z Position: Well, I'm very worried about the gigantic mass of rain over the plains, so I will position myself on the western fringe of it near Woodward, OK hoping that clearing will occur by mid-afternoon and a potential outflow boundary will move across the region. I see decent directional shear on both the DDC and OUN soundings. Hopefully we get some CAPE later on...

15Z update: Well It looks like things are going to get interesting over TX Panhandle/W OK/SW KS. I'm going to place myself within reach of most of these areas and monitor the ongoing storms in the area. Maybe pick up a few hailstones en route to Seiling, OK. I have good road options here. I can scoot north to Pratt, or south and west into TX toward Canadian. I'm seeing potential for many boundary interactions today. Picking out where they will be and where they will intersect the most unstable airmasses is the key to success!

 

[Patrick Martin]

I'm still on the road but with convection going up in the OK panhandle, will continue past Boise City to Amarillo, TX. I should be rolling into town just as all the 18z data comes out.

 

[Brian Stertz]

I think I'll hold in the Plainview TX area for now...although I am a bit concerned of a WF hyper jump into KS. For now that is my plan. Just am liking the nice 850mb theta ridge poking up into the Caprock on 12z UA data. Think that may be a signal along with yet another wave upstream over NM ready to come popping out later in the day.

 

[Paul Austin]

Reading the 15z: It's still very early in the day so see no need to jump on any convection in the area. Winds are backing nicely across the TX panhandle so may move back west towards Amarillo, TX

Verne, may not be time for lunch, but if so, what do you recommend in Amarillo? Meet you there!

 

[Paul Townsend]

After fretting and heming and hawing for over an hour based on 15Z data, I leave Dodge City at 1615Z and head down in the direction of where I should have been from the start. I head south on US 283 to west on US 60, then south on US 83 toward Childress, TX, observing the horizon to my southwest all the while. Projected arrival time is 2045Z - 2100Z. I may stop along the way for data, so Shamrock, TX may be an intermediate stop.

 

[Bob Hartig]

I'll join the convoy in Amarillo. I'm tempted by DDC, but I see the best upper-level support happening in the TX panhandle on up to OK.

 

[Corey Sloan]

Read 12Z Update--Initial Target: Dodge City, KS

Read 15Z Update--Target: Liberal, KS--Concerned about overnight convection, cloud cover and afternoon heating being significant enough to destabilize the atmosphere.

Target choice reasoning: Temps already in the upper 60's, cloud cover is beginning to break and think temps could rise into the mid 70's as long as the broken overcast clears rapidly, Dp's are in the mid to upper 60's and appear to be nosing into the OK panhadle/SW KS (Theta E Ridge???)there appears to be several outflow boundaries visible already on the vis satellite pic N of DDC and GCR (could be me just wishing), wind parameters, UL support in SE CO/SW KS????, and better road conditions here than in DDC.....taking a stab at some better forecasting...either got it right or look like a fool... have looked like a fool before and still willing to learn....thanks for putting Chase Case #10 together...they have been interesting and a GREAT learning experience!

Now back to some of the earlier posts to see how I faired!

 

[Jim Tang]

Moving SW to Pampa, TX. Junk convection in SW OK is going to screw up things in OK, it appears. Lots of OFB's in the TX Panhandle so something's bound to happen there.

 

[Greg McLaughlin]

I am going to start the day in Shamrock, TX. I will definately move from here, but I have a good road options to go north, south or west. I will be keeping an eye on outflow boundaries and I like the stronger mid-level winds over Texas. I think there could definately be a couple of monster supercells if things set up right and we can get an outflow boundary to setup somewhere in the Texas panhandle.

 

[Verne Carlson]

Verne, may not be time for lunch, but if so, what do you recommend in Amarillo? Meet you there!

There's a new Cheddars' Restaurant at I-40 and Western St - great $5 burgers, meet you over there!