4/9/04: FCST: N TX & S OK

[Amos Magliocco]

12Z ETA depicts a shortwave crossing the Red River Valley region around midday Friday where a recovering airmass may hold sufficient instability to fire storms along and north of a projected dryline push. Low level wind trajectories for the next 48 hours are not particularly supportive of recovery which is why depth of moisture looks like the biggest fly in the ointment right now. Deep layer shear and forecast SRH values appear supportive of rotating storms, based on the 12Z ETA.

It's the last show in town for a while afterwards as well.

[Chris C Sanner]

Ok, here's how I view the situation.

A)I am free the whole day
B)Its Good Friday (Red River Good Friday Tornado Outbreak sounds good)

It has the makings of a historic event if you ask me ;)

Now seriously, I think the lack of moisture will hurt us somewhat but I have seen higher moisture returns before so I'd say pack the equipment and be ready..

[Mickey Ptak]

Well the current 12Z ETA run shows the triple point over Wichita Falls, Tx by OOZ Friday. Moisture return (according to the ETA) isn’t all that bad, low 60’s at this point along the dryline. Cape values of 3500 in south Tx and 1500 in Western Ok. The current run also indicates 3km Shear is forecasted at 32 m/2 with Helicity value, along the red river, at 380.
Just a quick 20 min forecast, but something to look for. Looks like it could be fun.

Mickey

[Shane Adams]

Haven't looked at models still (yet), but we're definitely going out Friday, if for any other reason, as Amos mentioned it's the last show for some time. I'm always an optimist in Spring.

Yesterday was pretty much scoffed at, as March 27th would've been (had it not been in central OK). I like Friday to give us our next tornado(es).

[Blake W. Naftel]

I've been swamped with classes, exams, and papers as the final three weeks of my semester winds up (or down, depending on your logic). Since the ensemble models are not hinting at anything interesting until around the 15-20th of April timeframe, and since this is yet another weekend chase opportunity (I have FRI through MON off), may make the gauntlet down I-44 towards the RRV region Thursday afternoon/evening.

Not too optimistic attm, but we're bordering on mid-April and my chase time prior to working tours is limited. Will monitor this closely over the next 24 hours.

..Blake..

[David Draun]

Sure friday looks good, but what about the big flare-ups of storms this afternoon? I know this belongs in a Now thread, but I'm not authorized to start anything in this topic. But, right now there are 4 blue boxes from TX to AL and plenty of 60-65 dBz echoes contained in the watch boxes. I wonder if anyone is out there watching that. SPC includes supercell potential.

[Tony Laubach]

I may be crunched for time getting out that way, but if conditions warrent, I may also be joining the Red River crowd and heading out myself :D . My leave time would have me out of Denver late Thursday evening in which I would likely crash overnight in the TX Panhandle :sleepy2: and head out early in the morning for the Wichita Falls area (give or take 100 miles).

Not too excited over this, either, but it holds potential; especially since I do have the entire weekend off :thumbleft: ! A few of us left from IA with the same not-so-excited attitudes and look what happened :shock: , so I won't put anything out to pasture just yet. Will keep an eye on things through tomorrow and prepare my vehicle and equipment tonight just in case. Also will bring my lucky jersey 8) !

Tony

P.S. And as Amos pointed out, this is the last show in town for a while.. might as well chance it, eh! :violent3:

[Amos Magliocco]

What is this? Are we putting the band back together or something? LOL! Blake and Tony both heading back to the scene of our recent crimes. Man. I don't see any way I can join you guys--school is in major crunch-time at the moment. I'd have to pull some serious all-nighters if I made a chase of it. I'm probably sitting this one out, though I still like what the 12Z showed.

A

[Blake W. Naftel]

I too have alot on my plate, but most of which will be completed and handed in my Thursday afternoon. This is still up in the air for me, as I'd have to coordinate two, potentially three other people into this chase to even afford it. If a chase does materialize, would depart late Thursday afternoon, and hopefully make Tulsa for an early morning rest.

Will wait and look at new ETA data Thursday; but will be on the road for the 00Z runs (w/ no mobile internet). Perhaps I can rope Dr. Brown into the mayhem as well.

..Blake..

[Jeff Wear]

I hope we don't get too much precip behind the front to reinforce the cool airmass behind the front and drive it too far south during the day Friday. I'm kinda worried about all the precip the ETA is breaking out early in the day, and has the front further south for 00z/Sat on the 00z run than it did on the 12z run. Also notice that the GFS has been placing the low further east than the ETA - if the GFS is to be believed the best chasing would be in the bad territory east of I-35, but it is interesting to see how generous it's being with the moisture return. I haven't had a whole lot of luck chasing surging cold front setups so I'm kinda leery, but I'll definitely keep an eye on things and make sure I keep Friday afternoon free for a possible chase.

[Melissa Moon]

I'm going to be optimistic for now (because being optimistic is more exciting than being pessimistic), but not going to make any decision as to whether or not to go out until about 18 more hours or so.

[mikegeukes]

Severe Weather Event is over, removed information.

Mike

[Shane Adams]

Friday is developing as I hoped so far. I'm not worried about models varying; everyone's a pessimist when the models look good, but when they're not so good people tend to believe them more. I think that's just jitters, lol.

As I mentioned two days ago, we're chasing tomorrow regardless of the forecast. I see more tornadoes in our future 8)

[Amos Magliocco]

Originally posted by Shane Adams
Friday is developing as I hoped so far. I'm not worried about models varying; everyone's a pessimist when the models look good, but when they're not so good people tend to believe them more.

This seems like a wise philosophy. Taking the models literally 48 to 72 hours away is probably dubious. As I told somebody in chat last night, all I take from yesterday's ETA is that a midlevel shortwave will cross a marginally unstable boundary layer sometime Friday. All other details remain up for grabs.

For those in easy striking distance and who have the day off, however, it seems like a no-brainer. Why wouldn't you chase this?

What interests me about the 8Z SWODY2 is the discussion about ETA underestimating dewpoints. Every year this is a bone of contention with the models. My assumption was that ETA remained conservative with moisture return because of the unfavorable low level wind trajectories (see 850 winds from 0-36 hours). I was guessing that with a shallow moist layer, the dryline on Friday would tend to mix eastward very quickly and perhaps become more diffuse than forecast, thereby reducing its value as a focal point for convection.

While we're all waiting on the 12Z, can anybody talk more intelligently about return flow and trajectories? I was keeping up with Rich Thompson's work in this area a few years ago, but have since fallen off the wagon and back to my state of ignorance.

[Mikey Gribble]

I'm in like a dirty shirt.

[Tim Jones]

If the moisture return or lack thereof does verify by the 00Z ETA, I wouldn't be quite as concerned as I still think decent saturation in the lower levels could take place close to the low. My concern is focused on morning convection and cloud cover/lack of instability. If this occurs, one would have to hope dynamics would overcome this and perhaps a low-topped supercell or two could initiate in or close to the low. However, taking a closer look at 850-500mb . .looks like a decent dry air intrusion will help to clear things out. Wish I could chase. Good luck to those who do.

[Tony Laubach]

SHOULD LOW LEVEL MOISTURE INCREASE OVER WHAT IS NOW FORECAST BY THE ETA...LOWER LCLS WILL ENHANCE THE POTENTIAL FOR PERSISTENT TORNADOES...AND OUTLOOK MAY NEED TO BE UPGRADED TO A MODERATE IN LATER FORECASTS. Ooo that sounds nice... :headbang:

The car's packed and ready to go.. just awaiting a couple more model runs as I kill off the day at school. That and curious to see if the Day 2 goes MOD at the 1730Z update.

I've all but decided to head out.. school work is pretty well done (will be by tonight) and I should be set cash-wise (paycheck advances, gotta love 'em :love3: ).

Keeping an eye on things here from Denver, expecting to be on the road by about 10p tonight heading for an overnight stop in the TX Panhandle before making an early jog to the Wichita Falls area, hoping to arrive by or before 1p.

*crossing fingers*

BTW, anyone leaving from this direction who's low on cash, I'd be willing to pick you up along the way and share some of the expenses! Still trying to convince my buddy to escape the snow and tag along with me!

*again crosses fingers*

[Blake W. Naftel]

My high-tech non-scientific analysis to chase/or not to chase has been conducted as of 10:37am ET... and the Sakajawia dollar coin to which I flipped (calling heads) has indicated Friday is a go.

Not too worried about model runs attm; as they tend to underplay (as per the ETA) microscale events. Since I do not have the luxury of living in closer proximity to Friday's target of LTN to SPS to west of DFW; will be forced to depart Kalamazoo later this afternoon and pick up my chase partner(s) in IL - hopefully making Tulsa by early morning for some rest.

Will look over the 12Z ETA, but unless there is some hint of an Iowa'esque event transpiring over the next 36 hours, and baring any delays, I will be barnstorming across the Red River Valley around 21Z Friday afternoon.

Roll of the dice - Round II.

..Blake..

[Chris C Sanner]

I'm going to be hitting the Triple Point most likely. Depending on its location SPS to LTN is definately my early target. Depending on when they expect initiation tommorow, I should leave around noon-ish because its such a short trip out there. Everyone be looking for the white cougar with a banged up bumper! ;)

[Jason Montano]

I am going chasing on friday, that is for sure. I'm not too worried about the eta underestimating dp, it has steadily been increasing projected dp's for two days straight. This is the same thing the eta did with the 27 March event, until the day of, when it came inline with the gfs. I think its gonna be a good day for NW texas.

Tony, it's cool to see another Skin's fan around!! I am from the DC area and have seen nothing but Cowboys fans around here. GO SKINS!!

[Amos Magliocco]

After my exhaustive five minute review of the 12Z (LOL), I think things still look good. ETA is still stingy with the moisture and that's a possible problem as could be anvil blowoff from early convection limiting insolation and the growing diffusion of the dryline. But the model also appears to maximize convergence north of the dry punch and delivers even higher CAPE values than seen on prior runs. Tricky to take indices literally on these deals, I know, but still....

Overall the changes in this run are relatively marginal and it still looks good to me.

A

[Jeff Snyder]

Well, I'm going AWAY from Oklahoma later this afternoon through the weekend, so I won't be able to chase. Heading to NC for Easter.

At any rate... The big concern about any pesistant tornadic activity is weak mid-level winds. I mean, the ETA generally has 500mb 35-42kts over the area. This, in addition to 25-30kt 700mb winds, will spell slow storm motions. However, I'm largely concerrned about mid-level storm-relative winds. I really can't imagine SR winds at 500mb will be much larger than 10 kts, maybe. Thompson has done some research and found that SR-winds seem to be important in tornadic pesistance... So, I'm expecting that to be the fly-in-the-ointment as far as persistant tornadic activity is concerned...

Other than that, instability and low-level shear looks decent (though 12Z ETA shows 0-1k helicity very very small over in the warm sector). Looking at the wind profiles across the area tomorrow, I'm kind of concerned about the orientation of the front ... The 12Z ETA has it positioned NW/SE... Given an ENE storm motion, this would cause the storms to cross the boundary into lower instabilities. Whatever the case, far from the best setup, but depending upon storm mode, I could see a couple of tornadoes occurring... I'd analyze models more but am running out of time... Good luck to those who go out.

Jeff

[Tony Laubach]

So Blake's still flipping coins, eh! Just in case I don't catch ya between now and the time you hit the road, have a safe trip down! Going to be a long night for a few of us heading out, I think.

I've pretty well decided on going.. just some small reservations (not wx-related), but I think I should be okay *prays to God*. Still staying tuned for the latest developments in what could possibly be a 'Good Friday'.

Amos, cute comment about the band getting together! *LOL* Hopefully we'll knock 'em dead like we did a couple weeks ago! Sorry you won't be around to play with us!

Tony, it's cool to see another Skin's fan around!! I am from the DC area and have seen nothing but Cowboys fans around here. GO SKINS!!

Major skins fan here! Wore my personalized #81 jersey on March 27 (http://www.tornadoeskick.com/log040327.html) and it brought me all sorts of luck! Be watchin' for that to be covering my back once again on this trip!

[George Tincher]

I just took a look-see at the 12z ETA and GFS runs out through the period of around 18z tomorrow. At this time I hope the ETA is the correct solution. While both models displayed similar indices during that period, the ETA did show some fairly nice SE and S winds at the sfc, where the GFS showed nearly unidirectional winds from the sfc up through about 500 mb. I never wanna see SW sfc winds in the target area near the time of storm initiation! Let's hope the ETA is more accurate in this regard and that CAPE/moisture can be slightly higher.

As it stands, it appears to be a pretty decent set-up if the current ETA is on. I would like to see slightly better moisture/CAPE values, but it by no means looks terrible. I saw some 60-65 dewpoints punching into the target area by 18z and it appeared CAPE could be as high as 1500-2000 J/KG by that time. The directional shear appeared ideal with the ETA run. However speed shear with height wasn't drastic. On the other hand, as long as the winds are sufficient for venting, that's good enough for me, as many times I have seen good systems destroyed by overly high winds aloft.

All you guys to be in business is for slightly better TD's. If you could bump up the CAPE another 500 J/KG, that would only add icing to the cake. If that can happen I believe you guys will have a good day. But again, it doesn't appear terrible as things stand now. It may not reach historical outbreak proportions, but I see some tornadoes tomorrow. Now all I can do is hope those of you who chase also see tornadoes.....in your viewfinder! Good luck to those who go out.

-George

[Chris Sokol]

I have to take a test at school at 8 AM, then I am on the road. Probably take I-44 to Wichita Falls and get data (time to try the new wireless card out). Moisture return is starting to look better, although I agree that a 500 J/KG bump in CAPE would be nice...not that it matters. I will be out there anyway.

[Mickey Ptak]

I have to work until 8:30am. So I will be making my decision on a target tomorrow morning. Needless to say I am going. I really don't think the moisture is going to be as bad as some are making it out to be. Last time I checked 60 to 65 dw were not all that bad. Any way tomorrow’s analysis will paint the picture for this chase.

Have fun and be safe...

Mickey

[George Tincher]

The 1730 Day 2 still retains the 25% significant severe probability, so the SPC forecasters must feel there's a good chance of supercells and tornadoes, regardless of what the models are spitting out. Considering how often the models have been low on both CAPE and moisture leading into events this year, I am not placing a great deal of personal faith in them attm. I guess from this point forward it's a game of wait and see. Funny, isn't that always the case? Hehe.

-George

[Larry J. Kosch]

this posting has been deleted by LJK.

[Mikey Gribble]

Its from the movie dumb and dumber. I am a big fan.

[Shane Adams]

Well, my optimism hasn't fluctuated any after an intense analysis just now (intense for me is about 20 or so minutes, 10 on cable). I'm interested in both the ETA and GFs' stinginess with the moisture at 700mb....the ETA is somewhat lacking but the GFS is just plain arid. But then I realized that models are much like people, flighty and unpredictable.

The main consistency I see with both models is the nice concentration of CAPE at all levels in SW/SC OK/extreme N TX. I think this could be a major "finger" pointing the way to tornadic bliss tomorrow. Nothing I saw just now makes me feel confident in any one area 100%, but for now I'm liking my original target town of Ardmore. Of course, playing west of there will most-likely be the first plan of action tomorrow, but I expect to be in the middle of it by tomorrow evening somewhere along I-35.

I'm quite content to forget what I just saw and wait for the 0Z runs. Returned from work not long ago, so I think a shower and some Sam Adams are in order. I'll be back later after the 0Z runs.

I know that synoptically there's probably no big similarities, but I keep getting the feeling that tomorrow will play out much like the 27th, as far as initiation time/mode/evolution. The one difference I see is the large tornadoes will happen later into the event, not at the beginning.

[Tony Laubach]

Originally posted by Chris Rozoff
But who knows, I'm almost as insane as a *real* stormchaser.

And I am insane like a *real* storm chaser :D .. but I guess I'm not stupid, though... bad luck has forced me to withdrawl my name from the hat :banghead: .. on my way home to pick up a check, my car's front end began to wig out on me.. guess I knew it was due, especially after successfully surviving the 2300 miles I put on that bad axel going to Iowa, then down to Oklahoma and back :shock: . Fortunately it happened on Hwy. 6 five miles from my house and not in Sherman, TX 650 miles from my house..

In any case, with less than 4 hours before my departure time, I am going to have to take a sideline seat for this one (as it snows on me here)..

Best of luck to everyone, I will wear the lucky #81 jersey for everyone heading down! It's still early in the season, so I won't spit too much fire for this one :angryfire: .. glad I'll have some synoptic time to try and get this fixed and ready for when the real action starts!

Watchin' for ya!

Tony :cry:

[Anonymous]

I think tomorrow will be real borderline, but I will be out. I am thinking somewhere south of Chickasha and Pauls Valley in between 44- and -35, as tomorrow pans out I will decide 35 or 44.

[John Cameron]

If any of yous guys are within 45 miles of SPS, you can hear the audio portion of our signal @ 87.7 FM.

Best of luck to anyone. If you see a tornado in the area call 322-1153.

[Peter Wharton]

Originally posted by Chris Rozoff
Early in the year, a year that potentially looks miserable for chasing from a persistence forecasting standpoint. (i.e., Jupiter's redspot situated over the western united states)
Chris

Can you please explain this comment - for a relatively novice storm analysis guy - how did you arrive at this view?

Cheers,

Peter

[Kevin Scharfenberg]

The convective system in the panhandle down into southeast NM is resulting in a large cold pool at the surface. The 00Z temperature at AMA was 48, as opposed to the progged temp of 65 by the 00Z eta. To me, this does not bode well for tomorrow's chances.

More after I have time to digest the 00Z data.

[Jason A.C. Brock]

Hey John

Is that the # for one of the local stations in SPS? If so which one and should I ask for anyone if I see anything interesting? You interested in Tornado reports only?

Jay

[Kevin Scharfenberg]

Short version:
Tonight's convection looks disruptive to chase potential in Oklahoma and much of north Texas. Best threat shifting down into the area SW of the D/FW metroplex. Supercells possible, but low tornado threat.

Long version:
The 00Z eta and RUC models have no concept of the cold bubble of air accelerating southeast across west Texas. For example, the 00Z eta says the surface temp in Lubbock at 1am will be 62. I'll bet the house on "colder".

The vort max responsible for this convection will lift ENE into Oklahoma in the morning as it shears out. This will carry the convection east, as the dense cold air in west Texas continues to spread southeast. By morning, I expect a large area of stable air roughly northwest of an San Angelo - Ardmore line.

The weakening shortwave trough and continued strong zonal flow over the terrain in New Mexico will keep the surface low virtually anchored over far NE New Mexico. The sub-tropical air will ascend isentropically over the remnant cold dome. The weakening, shearing and lifting nature of the lead vort max makes me suspect the isentropic ascent will win out over any subsidence behind the shortwave trough, keeping Oklahoma grunged in most of the day.

Farther SW, down toward Abilene, the cold pool will have a better chance to be eroded during the day, as isentropic ascent will be much weaker. If we can keep a cold ridge from anchoring down into deep southwest Texas tonight, the 00Z El Paso sounding suggests the dryline may be able to sharpen up. So I'd look for a triple point to set up somewhere down in the Abilene-San Angelo area.

Storm motion estimates, given a reasonable 00Z eta forecast profile, would take storms toward the east southeast, keeping them out of the cold/stable air. Seasonably marginal instability, combined with shear profiles that are "okay but not that great", make me think widespread/significant tornadoes are not a major threat.

Initial target: Rising Star, Texas.

[Bill Hark]

Friday looks interesting but not exciting. On the 00Z eta, there is a nice projection of CAPE up to 1500 through central Texas that extends northward and shifts eastward by 0000Z into south central Oklahoma. SRH is better in central Oklahoma but there is still an area of 200 m2s2 that extends to the south into Texas. The low shifts into the Texas Panhandle with backed surface winds across the Red River Valley by 1800Z. By 000Z, those winds are progged to shift to the SW. Upper level winds are unimpressive. The strongest winds (250 mb) level are south of Texas with only winds of about 60 across northern Texas and Southern Oklahoma. The 500 mb are weaker with winds of 40 across the Red River Valley at 1800 Z and these shift to the east later in the day. I do like the change in wind direction: W,SW,SW and SE for 500 mb, 700, 850 and surface respectively. The CAP should be almost non-existant. I am very concerned about the ongoing convection over the Texas Panhandle that will shift eastward. Although some good boundaries may be formed, cloud cover will retard heating.

Right now, I would like to be staying in Wichita Falls, Texas.

Bill Hark

[Tim Vasquez]

I'm bothered that the MCS hasn't gotten far into OK / N TX, and new development persists in far E New Mexico. This is really beefing up the cold pool. MAF radar loop at 06Z is showing the outflow surging south like there's no tomorrow. If the MCS keeps putzing around out west then we'll be looking at sucky NE-SW boundary orientations to boot.

Tim

[Lance Maxwell]

Ya, tomorrow looks like total suckage. Looks like I will pass up chasing in favor of going to morning class and then heading toward the D/FW area in the afternoon to see the parents for Easter. Who knows, I may have just as good a chance of seeing something heading down I35 in the afternoon as I would if I were out chasing all day.

I will make one last check of the models in the morning to make certain of a final decision. However, attm, I find it hard to believe that anything besides some spotty (only decent) cells will pop tomorrow in lieu of the morning (and perhaps noontime) MCS.

[Kevin Scharfenberg]

The good news is, the MCS didn't blast a cold pool too far south. The bad news is I don't think it matters. The 6am surface map shows 60 dewpoints confined well south of San Antonio, and there is no mechanisim that far south to start moving the moisture farther north. Every consecutive model run has shown weaker and weaker wind fields over Texas, and this morning's nearly calm winds suggest it is coming to pass. I think the 09Z RUC has the right idea, and dewpoints will struggle to break the mid 50s in central and northern Texas.

I was looking forward to chasing today, but now it looks like a no-go.

[Mike Umscheid]

I like the I-35 corridor south of DFW, near Waco. Straight west to east 500mb flow around 35 with decent lower trop convergence on the dryline in this area on nose of richer moisture advecting north. Current obs this morning (11z) certainly don't look promising for moisture, thus a south adjustment, I think, would be necessary to realize 2000+ surface based CAPE. Should be a decent push on the dryline (enhanced convergence) around the US-84 latitude. Gatesville to Waco is my pick.... hope it works (I'll be chasing on the D2D today...)

Mike U

[John Cameron]

Originally posted by Jason A.C. Brock
Hey John

Is that the # for one of the local stations in SPS? If so which one and should I ask for anyone if I see anything interesting? You interested in Tornado reports only?

Jay

that # gets you direct to the channel 6 WX center. I would limit calls to promising wall clouds and tornadoes only. Just say who you are and mention Stormtrack.

[Kevin Martin]

My newly developed Math Analysis for Severe Weather shows a marginal day today. with higher risk being hail, and lower end being tornadic. here is my math analysis. I call it Martin's Law of Weather,lol.

FORECAST ANALYSIS FOR THE RED RIVER VALLEY< NORTH OF DFW METRO AREA ON HIGHWAY 35

Dewpoint Forecast shows a dewpoint at 62= 50%
Surface Temperature will be at 70 degrees= 40%
Low Level Jet inflow at 850mb will be at 20-25 knots= 25%
Surface Moisture Carrying Wind= 100%
700MB Dry Air Carrying wind= 100%
Upper Level Jet Stream will be blowing at 50 knots= 0%
500MB vort values= 20%
CAPE= 50%

Probability of Severe Thunderstorms is 55%
So with that 55% it corresponds with my charts on........

Severe Thunderstorm Risk.
NO SEVERE RISK(NONE)
GREEN ALERT(LOW)
YELLOW ALERT(SLIGHT)
ORANGE ALERT(MODERATE)<---
RED ALERT(HIGH)
PINK ALERT(EXTREME)

Type of Event.
NO SHOWERS
SHOWERS
NO THUNDERSTORMS
WEAK THUNDERSTORMS
STRONG THUNDERSTORMS
SEVERE THUNDERSTORMS<----
HIGH RISK SEVERE THUNDERSTORMS

Thunderstorm probability is 60%.
no Thunderstorms expected.
Slight Chance
Chance
Possible<---
Likely
Run For the Hills


HELICITY= 100-150 Weak Torandoes Possible F0 to F1 Damage

Hail values.

50%
100%
50%
50%
100%

added together is 350 or.

Greater than 3/4 inch hail possible!

And now for my discussion

Forecast Discussion.

Surging moisture from the South will result in very high dewpoints in the forecast area today. A dryline will move through the region setting a boundary for Severe Thunderstorms to develop. With CAPE values expected to be in the 2000-2500 range, expect explosive developments. Large Hail will be a large factor, and perhaps the largest threat of the day with these storms. Wind fields don't really show all that much in Tornadic activity, except for Oklahoma City, Northeastward towards Tulsa, Oklahoma, where the highest helicity values will be. If a tornado forms in any of these storms, it will have to be around that area, leaving Northern Texas under a very slim, to nil chance of a tornado, so im leaving that wording out. 500MB chart also shows no signs of fast storm movement, so strong damaging winds within the storms, and bow echo thunderstorms will not be a problem.

Main Concern: Large Hail. Isolated Tornado from Red River to Tulsa, Oklahoma.

MARTIN

Please do check out a map I develop a day before the action hits, and daily updated. My tornado watch, and severe thunderstorms watch, and the very first Tornado Intensity Forecast Map. Should help some of the chasers this spring if they visit the site.
check it out here.
http://www.powow.com/orbiteradds/severe.html

Kevin Martin

[Shane Adams]

Just completed a detailed analysis of ETA/GFS/RUC data.....and I now have two targets, lol. The first one is the area from Ardmore (my original target town) to Ada, OK. This area's pros include close proximity to the front (and subsequently the best backed surface winds), enhance local helicity, and the help of a decent 850 speed max moving through the area by 21Z. The cons of this particular spot are a potentially severe lack of moisture, bad chase terrain, and the possibility of clouds/ongoing precip messing up insolation. Hope I used that term properly, that's a big word for me :lol:

My second target is Brownwood, TX. Pros of this area are a much better fetch of moisture (especially at h7 per ETA), higher temps, and (if it doesn't mix out too much) the forcing of the dryline (or surface trough as nealras would have it) :D Cons include a lack of surface veering (although any decent storm could back the winds locally), and (per RUC) an indication of subsidence in the wake of (I guess) previous precipitation. UVVs looked good at h5 on the ETA & GFS, but the RUC has a complete void in this region, which to me says "subsidence." But I'm not meteorologist.

I'm leaning towards southern/SC Oklahoma and points east, betting on the front to jack helicities on any storms. However, I'm not commited to either spot at this time. I'm sure the 13Z SPC outlook will heavily influence my thinking, if they're anywhere close to what I've come up with.

[Shane Adams]

In all my model reading frenzy, I completely forgot to check out a current surface chart. Don't I feel silly now.....

[Chris C Sanner]

Call me an optimist but I've seen storms tornado in mid/upper 50s dewpoints before. Add in the fact they're going to be crawling around I'm still heading out. i'm adjusting my target to....Velma! Now I'm just gonna sit at home and when something begins to fire per the Satellite, NWS, and SPC I'll head out. I know I'm cheating, but I'm still confident there will be a sweet looking storm today.

[Shane Adams]

Originally posted by Chris_Sanner
I know I'm cheating, but I'm still confident there will be a sweet looking storm today.


Well, if your target is home - why not monitor conditions and watch for development? That isn't cheating; tons of chasers do this in the field, everytime they chase.

Back to the subject of today - I was pleased with the latest SPC outlook, they pretty much agree with what I'm seeing (though they are understandably more skeptic). Looks like we'll be heading to Ardmore.

Like you said, tornadoes in 50s dewpoints are not unheard of, and everytime I bail on a moisture-lacking, near-front set-up, I get burned (like on May 16 last year). I'm gonna gamble that a storm in SC/S/SE OK will take advantage of the shear/backed flow/helicity near the front and spin....and tornado.

[Chris C Sanner]

I plan to do that ;)

I'll probably see you out there today good luck to everyone going out and be safe!

[Tim Vasquez]

A big negative - Clear skies all the way south to the Gulf. It's sunny and bright here in Austin with calm winds. FWD's sounding is a huge problem... the mixed parcel yields a surface dewpoint of 50F, and barely squeaks in with what looks like a 300-500 CAPE. Corpus Christi's 64F dewpoint is an illusion because of its limited depth; mixed through 100 mb we get more like a 53F dewpoint and almost no CAPE.

Also lapse rates are poor. It will only get worse seeing as the 12Z RUC is going for 1 to 2C of warming at 500 mb.

Tim

[Tim Vasquez]

There's a patch of low clouds in the Texas Hill Country that bears watching. It appears to be stratocumulus from what I can tell, and it's overlaid with some faster-moving cirrus (indicated on DRT sounding). The RUC is not picking this up and it may represent a chunk of better theta-e later in the day. SJT VWP shows SSW flow at 20-40 kt, so if this patch represents anything it might be worth keeping an eye on parcels in central Texas up to SEP/MWL/FTW.

Tim

[George Tincher]

Well, as of 9:40 AM CDT, it appears that most of the rain is confined to areas of NC OK and points N of that, leaving most of S OK and TX rain free. Satellite shows some clearing over this same area, at least as far as the heavy cloud cover. Hopefully those remaining clouds will will disintegrate as the day progresses allowing some good heating to take place. Surface obs from the area will follow shortly.

-George

[George Tincher]

9 AM CDT Surface obs round-up

Ardmore, OK
temp: 57
DP: 50
Winds: Calm

Lawton, OK
Temp: 57
DP: 55
Winds: ESE @ 12 mph

Paul's Valley, OK
Temp: 61
DP: 46
Winds: E @ 5 mph

Dallas/Ft. Worth, TX
Temp: 64
DP: 55
Winds: SSW @ 7 mph

Waco, TX
Temp: 63
dp: 57
winds: calm

Wichita Falls, TX
Temp: 60
DP: 54
Winds: E @ 7 mph

[Mike Peregrine]

Hope everyone down there has fun today (enjoy it, because it may be the last chance for a bit) - hopefully moisture concerns become less of an issue as the day goes on and that good air trucks itself northward ... things might still pop with 50-55td ... maybe dryline forcing will help make up for any deficiencies.

Mike U - wish you were chasing on more than radar ... would make for good video tomorrow ... have a safe trip up to Lawrence - - -

[Kevin Scharfenberg]

With surface heating underway (or soon underway) in southern Oklahoma, I think weak evapotranspiration and "dewpoint pooling" will be sufficient to raise surface dewpoints to the 58-60 range. Advection alone is certainly not going to do it with such weak wind fields! Those dewpoints will be quite shallow, as the regional soundings suggest 11 g/kg is the best we will be able to muster for the mixed layer.

So, given this idea, the fact I have the afternoon off and nothing better to do, I will probably wander on down to southern Oklahoma to play along the remnant boundary, perhaps where it intersects the weak/diffuse dryline. Deep shear is sufficient for supercell structure, but the high cloud base and poor low level shear suggests tornado potential would be limited to landspout-type vortices.

Target: Alma, Oklahoma (someone else already picked Velma!) 8)

[Angie Norris]

Was waiting for the magic 15z obs to come out ...
Looks like the warm front is currently lurking south of DFW. Big negatives so far are the dewpoints and winds. A good point is the clear skies so should be more than sufficient warming. Also like the 50 KT SW winds at 500 mb...at least there's shear. Hints of the dryline look to be setting up in the eastern Panhandle area.
If I were out there, think I'd be lurking near Gainesville TX. Unfortunately, I'll be cyber-chasing since I had to work last night :( .
Good luck, safe travels and happy hunting to all who are out!!

Angie

[George Tincher]

Well, I just ran another quick check on the sfc obs and dewpoints are still just in the mid to upper 50's at best over most of TX. To find a reading of 60 or above, I had to go all the way down to Houston. And the DP there was only 61. :(

It appears if it's gonna do it, it's gonna have to do it with 55-60 TD's at best. But I won't totally give up just yet. Hopefully there will be something out there to make it worth the trouble for those chasing. But I just don't see much in the way of moisture advection heading northward.

-George

[John Cameron]

storms or no storms, let it be known that at 12Z its 37F in Denver.

Have a nice day!

[Chris C Sanner]

Currently dewpoint in Duncan is 59 and at my house (measured) it is 59.8. Still waiting patiently here in Velma...