5/13/05 TALK: Southern Plains

[Jason Montano]

Well, I'm not real sure about today but I believe I will be playing the small dryline bulge the RUC is forecasting in SW OK. It is still early so the target may change. I am not crazy about the cold front and think farther S there will be a couple hour window for Sups. Since I am in Childress right now I'm gonna hang tight for at least the next RUC and the 1630 outlook.

EDIT: sorry I changed the Thread to TALK from FCST

 

[Bill Schintler]

Chase target for today, May 13

Chase target:
Childress, TX

Storm initiation:
3 PM CDT.

Storm type:
Isolated supercells with large hail and possible tornadoes.

Discussion:
14Z SFC analysis showed a CF extending along a LBL/AMA/LBB line with low pressure centered near AMA. 60F dewpoints were in place much of the area to the E of this feature. SFC streamlines show a nearly stationary outflow boundary along the Red River, while visible satellite shows further evidence of moisture in ERN TX panhandle with extensive ST which was eroding from the W. Moisture was fairly shallow as the atmosphere has been worked over by a couple of convective complexes – at 850mb the 10C isodrotherm was SWRD of a MAF/CDS/CSM/MWL line in TX and OK with a 30kt LLJ over the area. KFWD sounding showed only a 100mb deep moist layer, OUN was dry with convection having just pushed to the E, while a 250mb deep moist layer had worked NWRD to FSI near LTS in SWRN OK. 700mb temperatures were generally AOA 5C S and W of OK, with the best winds of 30kt lifting E of the area. Today, the right-entrance of a 50kt 500mb streak will lift through the area. WV imagery shows a couple of moisture streaks in ERN NM and through the TX panhandle, with the main streak inside of a MNS/CDS/OKC/MAF line. Storms should initiate along the NWRN edge of this feature where a local area of upper divergence likely exists.

Airmass is becoming increasingly unstable and by mid-afternoon MLCAPE’s should be well in excess of 3000J/kG. Shear and hodographs look impressive immediately N of the outflow boundary – with SRH’s (0-3 km) AOA 300 m^2/s^2 and deep layer shear around 40 kts. These parameters along with LCL’s in the 1200m AGL range should support a full spectrum of severe weather today as the CF/DL surges towards the target area late in the afternoon.

- bill

 

[Mickey Ptak]

I am hoping things will hold off until after 4pm so I can go. As of right now and with the limited data I have looked at Altus, OK would be a great start for today. I am still a bit shaken from yesterday but the chaser spirit is still alive and well unlike my nerves.

Mick

 

[Shane Adams]

Chad lawson, Jo Radel, and myself will be leaving OUN around 1pm or so. Target not refined as of yet but suffice to say we'll be heading southwest. Hopefully Mick can get out of work and join us

 

[Douglas Mitchell]

Sitting in Norman now, I'm about to pack up and mosey on down to either Lawton or Altus. If RUC verifies I'll be in good position, if the NAM verifies, I'll be heading down south a little bit to the Vernon, TX area. Tor potential is bleak, but hopefully I'll get better structure than the last couple of days.

 

[Philip Flory]

Currently sitting on the east side of AMA at Flying J. Was planning on heading back to ICT today.. however have decided to chase. Am not as excited about today's prospects as I was yesterday, especially with much weaker low-level flow. However, I am not going to leave directional profiles and 3000-3500 J/KG SBCAPE. Am going to go grab some lunch in lil while then proceed down towards CDS. Current thinking is best supercell threat may be a tad further south, especially if RUC verifies.. I really like CDS over to Vernon and down to the Guthrie area. Despite low-levels... think a few isolated supercellls are a near certainty and structure freaks should have a ball!! Still think we will see a couple tornadoes.. especially by late afternoon. Good luck everyone staying out of the hail!!

 

[Marcus Opitz]

mod risk out of spc for the sw portion of OK. On vis sat it appears to be a few well defined boundrys from earlier convection.

 

[Jeff Snyder]

I think there is a definite possiblity of some nice tornadoes down near Altus, Childress, Quanah, Vernon, Wichita Falls, and Lawton (welll, the sw OK / western north Texas area). Nice ESE flow behind a little boundary, with signficant destabilitization north of the boundary possible by mid-late afternoon. Current model runs showing 2000-3000 CAPE in the area, with possibility for strong low-level shear. 45-50kt 0-6km deeplayer shear per 12z NAM will help with strong supercells, and the NAM's 250-350 0-3km SRH in the target area will help tornado potential. If it wasn't for the fact that I have a final at 1:30pm and graduation at 7:00p, I'd be down there! Stupid graduation... I missed yesterday's event because I had final come into town and had to study for todays final... Oh well, I set my eyes open end of next week I suppose ... but i digress...

Just issued HWO from OUN:

THE MOST INTENSE STORMS WILL BE CAPABLE HAIL UP TO THE SIZE OF BASEBALLS AND WINDS UP TO 80 MPH... AND SUPERCELLS OVER WESTERN OKLAHOMA WILL BE CAPABLE OF PRODUCING STRONG TORNADOES BETWEEN 5 AND 9 PM THIS EVENING.

 

[Brett Adair]

Well...since I am not out chasing today I thought I would give my input.

Proposed Target Area: Mangum, Oklahoma

Storm Initiation : 3-4 PM CDT

Storm Mode : Supercells evolving into MCS by 8-9 PM CDT

Latest RUC indicates a nice little moisture surge east of the dryline this morning with SFC low becoming nearly closed off around LBB @ 1008mb. SFC low may reorient itself later in the afternoon as a double barrel feature and enhance shear near the OB/DL as right entrance of a 50-55KT mid level jet plows in. Thermodyamic profiles indicate destabalization continuing with very nice dewpoint depressions along the dryline. As dryline begins to bulge by 21z, a triple point feature could come into play as the OB continues moving north along the Red River. Analysis indicated SBCAPE values of 3500-4000J/kg which will aid in vigorous convective development. Although, low level flow is a good bit weaker than yesterday I believe microscale features will come into play with the boundaries left over and give someone across the extreme NE TX/SW OK area a rather significant torando later in the afternoon.

MESO-analysis already indicating 1KM Energy Helicity Indexes topping 4 at the present time ahead of the dryline. As PBL moistens up along the baroclonic zone, supercells should develop rapidly and hold there own for a few hours as deep layer shear of 40-45kts will be present and sufficient enough. A few classic supercells are a good bet, but I am going of more an HP probability before going MCS.

Just my .02...

 

[Tony Laubach]

The survivors of yesterday's Caprock action are sitting in Childress where we stayed last night... not looking to go very far except we eventually have to check out of this hotel! :lol: Liking our general area and may move very little between now and then.

 

[Brett Adair]

KFDR is already indicating some SHRA developing in Dickens Co., TX. This looks to be developing along the dryline already. Hope things don't get started a little too early....this is the region where EHI values are pretty spooky.

 

[Kiel Ortega]

Had at look at the 12Z RUC forecast soundings...given the nearly straight hodographs and the instability present, it might make for an interesting night in W OK. If these soundings verify, wouldn't be surprised to see left splits flying north around 40-50 mph with 3" hail! Might have to skip the big OU graduation ceremony to work (and play ) :lol:
...should be fun to watch.

 

[B Ozanne]

Looks like I've got a solid evening of armchair chasing ahead....I'm such a dork.

If a few people are looking for some SMS or email nowcasts once initiation has begun send me a PM, I can probably help out about 4-5 people.

 

[Gabe Garfield]

Target: Quanah, Texas (perhaps a bit north toward Hollis)

ETD: 1:30 pm

This is an absolutely classic mid-late spring supercell setup. E-W oriented outflow boundary with moderate CAPE on the north side of the boundary and strong CAPE on the south side. The outflow boundary alone would do it today, but it looks like ambient wind shear is not that bad either (e.g., 40 kt winds at 500 mb). Personally, this impresses me the most about today...good deep-layer shear with strong-extreme instability and an outflow boundary. If things setup just right, we may have a repeat of last night's event (although it'll be hard to top).

Gabe

 

[Nick Parker]

A few SVR warned storms boiling up around here in Southern Illinois. (Massac, Johnson, and Saline counties) PAH NWS was saying nickel hail in northern Massac county. Looking forward to tonight as the CF comes through. Should have a better setup. I'll be able to chase then!

Good luck to all out there!

Nick