4/23/07 FCST: TX / OK / KS / NE

[Dan Robinson]

This morning, the RUC is showing a DL bulge south of I-40 in the TX panhandle. It is also keeping CIN until late evening. Not much of note in the way of boundaries showing up on radar, and with the cloud deck, visible satellite isn't going to be of use until things clear out. The panhandles have some work to do in getting the 60f dewpoints further north and west. Surface winds backing won't be a problem anywhere. Upper support could be better during the late afternoon, but it is there nonetheless. My main concern is the large cloud deck moving NE from Mexico, which on its current trajectory evident on the IR sat loop looks a little troubling.

My preliminary target this morning is Canadian, TX.

 

[Jim Bishop]

Cloud cover is my only concern. I'm a little surprised it hasn't been discussed more. Otherwise the Eastern Texas Panhandle looks like a tornado goldmine 5-8pm tonight.

 

[Mikey Gribble]

Well I'm definitely not off to a good start this morning. I swung home from work to take a quick shower and change before I headed out of town and I managed to lock myself out of the house on my way out. Now I'm sitting on the front porch waiting for somebody to come let me in so I can grab my keys off the couch. Luckily I had my laptop in hand so I can do some forecasting while I wait.
I am planning on heading towards Woodward to do some forecasting before I pick a target, so my forecasting has been somewhat minimal up to this point. I'm just going off of last nights models and this mornings current conditions. That being said, everything seems to be coming together very nicely for a tornado outbreak. I expect a couple cyclic supercells to form in the TX and OK panhandles and I think strong tornadoes are a good possibility.
The one thing that worried me first thing this morning was the cloud coverer with the subtropical jet, but after watching WV imagery for a while I decided that this was only going to limit the southward extent of the threat and that from Elk City North would still get plenty of insolation. I didn't put much work into extrapolating how far SE I thought the cloud deck would move, but I am pretty much in agreement with southward extent of the threat area on SPC's new outlook. Moisture is looking good on morning surface obs. Not much else to say that hasn't been said already. This is about as perfect of a chase day as you can ask for in any given season. I am heading West here shortly (maybe Woodward) to do my forecasting and pick a target. I will post from there. Good luck to everybody today.

 

[Shane Adams]

Cloud cover doesn't concern me because it's 9:35am....by 5pm, all will be right in the Universe. Interesting to note, it was warmer at 4:45am here in Norman than it was at midnight. Looks like another jaunt out west on 40 to Shamrock and that wonderful, hospitable Best Western and see how things play out from there. Could be another long into-the-night type of day like Saturday was, considering the dynamics that will keep on cruising in. Nothing technical to offer, just put me east of the DL bulge and I'm a happy man.

 

[Bill Schintler]

Chase target for today, April 23

Chase target:
30 miles north of Childress, TX.

Timing:
Storm initiation 5 PM CDT.

Storm mode:
Supercell storms with isolated tornadoes.

Synopsis:
WV and UA analysis indicate a potent shortwave over NRN NM ejecting from base of SWRN CONUS trough. Associated with this feature is strong mid- and upper-level cooling, with H5 temperatures of -21C in NWRN NM. Surprisingly, marginal mid-level lapse rates are associated with this feature however the ABQ sounding indicated about 8C/km in the 800mb-600mb layer. A CI shield, located along and S of an AMA/GAG/ICT line, was associated with the SRN branch jet. At the SFC, the boundary that had pushed into OK yesterday had washed out and strong moisture transport was underway as SERLY flow was present over all of OK and TX. Moisture depth was plentiful, about 4000ft deep per FWD and OUN soundings; while the WRN extent of the moisture was AMA where the moisture extended from just above the SFC to a height of 1000ft AGL.

Discussion:
Today’s convective forecast is difficult as the details of the upper-level forcing are not obvious because of the interaction between SRN and NRN stream jets. It now appears that a pair of compact mid-level shortwaves will translate through the SRN jet branch. By 00Z, the first wave will be approaching FWD while a second speed max will be near DMN in NRN Mexico. Further north, areas around LBL and DDC will be in the favored left-exit region of the NRN branch streak. SFC low-pressure will track E along the CO/NM border while a WF will extend E of this feature. Curiously, both the 12Z NAM and RUC initialized too low with SFC moisture. A DL will slowly mix EWRD in the TX panhandle and the most likely location for convective initiation may be just N of CDS which will also be located at the NRN periphery of the aforementioned retreating CI shield. Impressive instability and shear parameters will be in place however a potential negative for tornadogenesis may be the large dewpoint spreads of approximately 15F, however storm-scale modification of the BL following establishment of convection should lower this.

[FONT=&quot]- bill[/FONT]

 

[Ray Walker]

I agree with shane that shamrock would be a great starting point like soooo many other times this year. I will be doing the same and will be heading out around 10:30am. I think that anywere along the dryline in the eastern panhandles on into western Oklahoma is a very good place to be today. Although I do not think that storms will be widespread there should be several very nice tornadic supercells in the panhandles today.

 

[Glen Romine]

After looking at everything carefully, I still like this setup a lot, but there are 3 things to keep an eye on:

1. Obviously weaker winds aloft moving out over the plains too late would be a negative, with less response in the low-level winds resulting in smaller hodographs before nocturnal stability sets in. In this case I think we'll still get nice supercells with adequate deep shear but tornado threat would be a lot less.

2. Cirrus will probably be brought up from Mexico on the subtropical jet. If too thick insolation may be inhibited so that initiation becomes a question.

3. A subtle shortwave trough in the subtropical stream might be badly timed, moving over Oklahoma during the midday. If this feature is strong enough there might be subsidence in the wake of it over the dryline during peak heating, a negative to robust convection.

Nice observations Kevin. Indeed, there is a considerable amount of cirrus pouring in from the subtropical jet. Also, last night's and this morning's NAM runs continue to show a significant ripple in the subtropical jet arriving too early in the day leading to large scale subsidence over much of the dryline during peak heating. Looking at WV imagery this morning, it is somewhat difficult to discern which of the many ripples in the ST jet the NAM was picking up on. I can see one over about El Paso right now, and another pair of stronger waves upstream around the Baja and western Sonora. I think you would hope there is another wave in between for the best chances of CI on the dryline further south. Interesting that the 9Z SREF has the dryline setting up well east relative to the latest RUC. The dryline bulge in the RUC toward CDS appears tied to the 850 mb thermal ridge - but the forecast high temps in the RUC might be tough to reach with the degree of cloudiness present. Perhaps a better chance of favorable conditions will peak through along the northwest edge of the CI shield as the low-level moisture is drawn back northwest. Right now I like the theta-e nose as it develops from GAG back toward LBL.

 

[David Wolfson]

An obvious attraction is mid-50s dews pushing into se CO with tons of helicity, good upper support, dryline, etc. On the other hand the Panhandle has magic this year and I'm skeptical that the good moisture will make it that far, especially if storms start to fire farther south. As Glen says, the sunny side of the mid-upper cloud deck and theta-e nose is a good starting point, I think.

Virtual target: Liberal, KS, and be ready to roll.

 

[Chris C Sanner]

Nothing more to add that everyone else here hasn't already added. I'm expecting initiation somewhere along the dryline this afternoon and the best best might be near or just N of the dryline bulge. I'm gonna put myself in the middle of things at Shamrock or some other town in the area with WiFi and just hope we get storm within reach and before dark. Either way, I've missed both big panhandle events due to injury/illness so far this year and I am not about to miss another...leaving within the hour.

 

[Jason A.C. Brock]

I am HEADED FOR THE GENERAL AREA OF CHILDRESS. ILL CHECK DATA ETC WHEN I GET THERE BUT I AMA LITTLE CONCERNED THINGS MAY BE MOVED BACK TO THE WEST A TAD. THE DRYLINE AND WARM FRONT SEEM TO BE RETREATING WESTWARD AND IF WE CANT GET CLOUDS TO CLEAR WE MAY NOT SEE 80 DEGREES IN THE SE PANHANDLE.....BUT THE WHOLE CLOUD THING HAS WORKED OUT FOR US SO FAR THIS YEAR WITH IT DISSOLVING AND THEN STORMS ERUPTING BEHIND IT AND AHEAD OF DRYLINE. I WOULD BE PREPARED FOR THOSE IN SHAMROCK AND CHILDRESS TO POSSIBLY KEEP IN MIND A SLIGHT MOVE WEST MIGHT NOT BE A BAD IDEA. I COULD CERTANLY SEE STORMS ACTUALLY FIRE AS FAR WEST AS I-27 OR RIGHT ALONG THE CAPROCK. IT WONT MAKE TOO MUCH DIFFERENCE AS THERE IS GOOD DATA POINTS IN CHILDRESS AND SHAMROCK.
I CAN NEVER REMEMBER THE EXACT LOCATION BUT THE REST STOP BETWEEN CLARENDON AND CHILDRESS ON 287 ISNT A BAD SPOT. I MAY HEAD THERE AFTER A BRIEF STOP IN CHILDRESS FOR GAS AND OR SOME GOODIES. THEY DO HAVE BLARING FAST WIFI THO.
HOEPFULLY THE 207 CORRIDOR WILL LIGHT UP. STORMS SOUTH OF I-40 SHOULD BE A LITTLE MORE ISOLATED AND SLOWER STORM MOTIONS AND SLOWER THAN ON SATURDAY.
SORRY FOR CAPS MY DESKTOP CAPS LOCK IS ON THE BLINK. IF I POTS LATER IT WILL BE ON LAPTOP.

 

[JR Hehnly]

I'm headed up to the Weather Center to pick up today's passengers. Looks like we will be headed towards Shamrock as well.

Today we will be testing our new online tracking system. Current position and webcam images are at:
http://cps.okstorms.com

Hopefully it works, was up writing code until early this AM.
I am user 0000, we may have another user on this afternoon as well. If it works I'll start adding more beta testers to the system.

 

[Matt Hines]

Welcome back to the Panhandle! I agree that the dryline will be even farther west than even the models have it by this afternoon. Why?...

1) CI will prevent a lot of mixing

2) Each model run is farther west and that has definatly been the trend this entire severe season so far.

3) Moisture is returning through the South Plains and Southern Panhandle this morning with Td's in the upper 50's lower 60s.

So, be careful of being too dependent on the models! They do not understand the terrain issues to well out here. I would say the central and northeastern Panhandles are the places to be. Good luck! Just hope we can avoid towns with this event.

 

[Mike Johnston]

Besides the well-discussed influence of the sub-tropical jet and associated cloud cover (which seems to be more of a hindrance than a supporting factor at this point), it looks like the eventual latitude of the main lee cyclogenesis will persist as an uncertainty over the next few hours. It's moved all over the place on the RUC over the last several runs. SPC's outlook seems very firmly anchored to development of surface cyclone at Denver's latitude, while the latest RUC has it over N Central New Mexico!

With these uncertainties, and in concurrence with Glen's observation that it may be prudent to position NW of the cloud cover, I would be setting up in Liberal, KS at this point and closely monitor - reasonably good road options in all directions and near the apex of the theta-e ridge. If SPC's thesis is at all on target, with very friendly storm motion vectors, this spot should position one well to pursue mid/late-afternoon sups moving off the front range into the western tier of KS counties (with increasingly supportive parameters), yet still in position to drop down to emergence of any activity in TX panhandle ahead of the dryline. In this regard, looks like the RUC has backed off from one broad-arching "bulge" to a much flatter arc with hints of tighter localized bulges.

Good luck to everyone out there, and if you find yourself without a nowcaster, PM me and I'll give you some help.

 

[Brian Stertz]

Here we go again !!!!...Noon Update

Update: closer inspection of SPC Meso parameter page shows impressive 850-500mb criss-cross across SW Kansas...growing increasingly concerned that areas south of the northern top tier of counties in the TX Panhandle may cap off strongly. I am pleased to see what looks a good theta nose poking northward now well east of the Caprock into the E.Texas Panhandle and far W.Oklahoma. Time will tell exactly how things will be set when tee-off time happens but at this noon hour, I am certainly in full agreement with the MDT risk placement.


Trying to make some important chase decisions, and after being singed by the RUC on Sat., I am a bit skeptical about things. I am with Rich and Ryan and are HQ'd in the Canadian TX library. It's very hard not to peek too much at tomorrow's 5 ring circus , but certainly can see that things may get pretty hairy today from a dryline-warm front intersection near Liberal KS southeast towards the Pampa TX area....a significant theta ridge was forecasted to be setting up along the dryline, with a definite poke into SW Kansas. Also on the significant side of things is some strong wind energy that is due in to the N. Texas Panhandle...E.Oklahoma Panhandle and SW Kansas after the supercells fire on the dryline. Looks like another severe case of Texas Panhandle magic is in store this afternoon from Gruver to Pampa and areas east-northeast. I have also some concern about the warm front which is northbound and may align itself along the OK/KS border east-west from the Liberal KS area eastward to north of Alva. The directional shear profiles are immense, but inflow a bit weaker in SW Kansas than the TX Panhandle where a better blend of LL inflow and increasing deep layer shear may support more intense rotating updrafts and tornadoes. We passed through a pretty serious boundary north of Wellington TX earlier and this boundary should continue to shift northward. LCL's look very favorable by evening with sub 1000 LCL's forecasted. We will probably hold our position here in Canadian as things continue to gel and the chase target becomes locked in. Still a few things to figure out....

 

[Billy Griffin]

Okay, this one will sure spark controversy and probably a few laughs as well, but I'm somewhat skeptical about today. I'll just jump right out and say it... this day reminds me EXACTLY of May 2nd, 1999 (the day before the BIG day). While I'm no pro at model interpretation and don't claim to be, what I do see is that the storm system now digging in over Vegas could possibly cause the dryline to BACK UP today, yielding no event at all, or at least stuff remains capped south. With the dryline backing up, perhaps then tomorrow will be the day it kicks out and Oklahoma sees the kind of outbreak we haven't seen in several years?

I'm not predicting another 5/3 OK event, by what I am implying is that I do remember sitting out in western OK that day on what was predicted to be a very productive day for tornadoes. And as I sat there talking with other chasers, all we could see is the dryline backing up to the west. The very next day... well, you know.

As most on here know, I'm normally not one to get all excited about these events until it happens, but these past few systems have caught my eye because of their origin (Gulf of Alaska) and the observed pressure falls off West Coast as the trough digs over the West. Again, I'm not predicting another May 3rd event, I'm just saying that it reminds me of that series of days prior to and of the day. Just a two-cent opinion/observation.

Good luck to everyone today. I'll likely head out from work around 3pm"ish" and out west on I-40... just in case something goes. I still fear that "if" it happens, it could be more of a nocturnal event - - - but for chasing & safety, I hope that I'm wrong. Be safe everyone!