2/23/07 FCST: OK / TX / KS

[Gerard Jebaily]

Im in full agreement with you Jim. Im not sure how thrilled I am about going. The mod risk might give us some confidence but after reading the discussion, my hope of some day time storms has vanished. I really want to go and give it a shot to see what will happen, but I have a feeling that I will get to Elk City (my target at this time) around 3-4 pm, sit there, sit some more, and after sunset watch some cells quickly become a broken squall line. Night time chasing is nobody's favorite because of how dangerous and frustrating it can be. But at this point, im considering it because of its relatively near proximity, because I will be chasing it back towards home, and because im storm starved like everyone else. I will probably go, and after spending $150+ realize I should have jus stayed in Norman and waited for it to come to me. Somebody please talk me out of my stupidity, or join in with me.

 

[Jim Bishop]

Im in full agreement with you Jim. Im not sure how thrilled I am about going. The mod risk might give us some confidence but after reading the discussion, my hope of some day time storms has vanished. I really want to go and give it a shot to see what will happen, but I have a feeling that I will get to Elk City (my target at this time) around 3-4 pm, sit there, sit some more, and after sunset watch some cells quickly become a broken squall line. Night time chasing is nobody's favorite because of how dangerous and frustrating it can be. But at this point, im considering it because of its relatively near proximity, because I will be chasing it back towards home, and because im storm starved like everyone else. I will probably go, and after spending $150+ realize I should have jus stayed in Norman and waited for it to come to me. Somebody please talk me out of my stupidity, or join in with me.

Ha, someone should talke ME out of this. I'm in Houston..and looking at a 9 hour drive solo. Yes, storm starved has driven me to this kind of insanity! But also the prospects of Saturday in Kansas as well.

 

[Tony Laubach]

Guys, don't feel too bad.. there are several of us leaving DEN this evening for this! My faith isn't high for storms to fire long before dark, but its certainly possible. And I'm about to gamble 1500 miles and a couple hundred bucks to find out! We'll be on the road at 5pm, Verne, Michael, my Goomba, and I!

 

[Scott Olson]

I wrote this last night, though I was a bit concerned with last night's model runs (namely the trend in decreasing moisture) I'm still going to go ahead with my departure now. Of course Saturday makes that decision easier.

Friday Feburary 23rd:
The magnitude of moisture transport will increase expodentially as the LLJ increases substanially. By 21z, sufficent instability will be in place for supercell development and vertical wind shear will also be very supportive as well. The big problem as of late has been the lack of upper support and only weak convergence along the dryline. There seems to be agreement from several past runs between the GFS & NAM that intiation will occur in extreme W OK by 6Z. Here we are going to explore two scenarios, one in which storms intiate at 21z and one in which storms intiate at 6z.
21z: The 21z KHBR sounding shows no CINH remaining during the crux of the greatest heating. In this instance either the presence of a shortwave or a mesoscale alteration to the dryline could help result in convective intiation. Instability is already 1000 j/kg (about 1/10th in the 0-3km layer) with 200-250 m2/s2 0-3km SRH (about 1/2 in the 0-1km level). LCL heights are already workable at around 900m. While all of this is intially supportive of supercells and possibly tornadoes, it gets significantly better as the LLJ/UL winds increase and moisture (instability) increases. Between 21z and 0z KGAG and KHBR show a doubling (or more) of MLCAPE, 0-3km CAPE and 0-1/0-3km SRH. By 0z KHBR ML inversion has been reintroduced but KGAG's weakens even more after 21z until around 0z. Given all the data avaliable, if storms could intiate and become rooted near the surface, tornadoes would certainly not be out of the question.

06z: Storms do not form during the afternoon but instead wait for more direct upper level support. Storms intiate across extreme W OK and extreme E TX panhandle. There is no depricable change in CAPE between 0z and 6z and SRH is only on the increase (0-1km SRH 300+ m2/s2 0-3km SRH 500m2/s2). All indications certainly look favorable for the intial storm-mode to be supercells, even at 11pm. The big question is just how elevated these storms will be? Since we are talking about a 60kt LLJ and even higher moisture rich air being advected in, I would suggest that mixing potiental as a result of the strong low level winds will help keep the BL together and the tornado potiental should continue to 9z. Just think of 3/11 and some of the other 2006 pre-event nights. In these cases the nocturnal tornadic supercells raged onwards towards midnight, thanks to the strong low level winds and increasing vertical wind shear from the approaching system. All caveats aside (certainly some noteable ones like intial moisture and lower probabilities of daytime intiation). I should note, I'm bias as I enjoy night chasing almost as much as daytime chasing (it's a different experience really).

 

[Rodney Harper]

This is a basic backyard chase for me but I don't know if I would drive and put in the hours and $$$$ like you guys are contemplating for this. It seems to me that this could bust pretty easy. I hope not but that is my .02

 

[Karen Politte]

The SPC upgrading to MOD doesn't signify to me anything that would make me more comfortable about leaving to go chase Friday. It does not signify that confidence in an all-time megaoutbreak of rotating storms is increasing exponentially.

I also don't believe that moisture return is going to be on the order of what some believe. We are going to get return, yes - but it is going to be a return of mostly regurgitated air from the Carolinas or NY. This air will have had less time out over the Gulf than I've spent forecasting today.

In the end - I expect some meager low-50Tds to make it across the Red River and into OK, probably after dark on the night of 02/23, once the LLJ really gets cranking. The quality of the moisture is going to be very poor, and I think any storms that do develop before darkness on Friday will look extrememly anemic.

I can't chase Friday - but we can chase Saturday. That said - we may not even go out at all for the whole event if it just doesn't look worth spending $$s in gas on. I'm surely not going to spend $$$s on gas and take a day off work to go chase Oklahoma on Friday - not in February and not with this progged lack of good moisture. I don't care how cold it gets "up there".

KL

 

[Mike Hollingshead]

I also don't believe that moisture return is going to be on the order of what some believe. We are going to get return, yes - but it is going to be a return of mostly regurgitated air from the Carolinas or NY. This air will have had less time out over the Gulf than I've spent forecasting today.
KL

The flow ain't from the Carolinas, it's from the western gulf, which is probably not that bad off. Sure there is crap air to the east from the east coast, but I think there is room in the western gulf for what is needed. Most of that flow went east, and I'd bet the weak push west pooled some in the western gulf.

ADN

BRO

sw GULF buoy 42002

 

[Gabe Garfield]

I also don't believe that moisture return is going to be on the order of what some believe. We are going to get return, yes - but it is going to be a return of mostly regurgitated air from the Carolinas or NY. This air will have had less time out over the Gulf than I've spent forecasting today.

FWIW, the trajectories are from the southern Gulf States, not from further east. In any event, the moisture will take the scenic route (Brownsville to Mexico to west Texas to the target area).

In the end - I expect some meager low-50Tds to make it across the Red River and into OK, probably after dark on the night of 02/23, once the LLJ really gets cranking. The quality of the moisture is going to be very poor, and I think any storms that do develop before darkness on Friday will look extrememly anemic.

Given extremely cold 500 mb temps (-20 to -30 C in the vort max), I think that low 50s will be more than sufficient for very significant storms (including tornadoes). You really can't ask for much better moisture in February, so I'll take what I can get.

That said, it is climatologically unlikely that a big tornado event will occur tomorrow. But then again, this is turning out to be a climatologically unlikely severe weather scenario.

Gabe

 

[matt patterson]

If we do not see action before sunset and things go up after dark, does anyone know what kind of ambient light we will have to work with??
Personally im pretty happy to even have a shot of severe weather this time of year so even if its some awesome lightning or hail im happy its severe weather season again.

 

[Robert Edmonds]

If we do not see action before sunset and things go up after dark, does anyone know what kind of ambient light we will have to work with??
Personally im pretty happy to even have a shot of severe weather this time of year so even if its some awesome lightning or hail im happy its severe weather season again.

You have a half moon, plus whatever the stom makes. Either way I'm not a night time chaser, and with the probability of it firing with little to no daylight I'm not going out chasing, but I had been weighing my options.

 

[afischer]

I'll probably chase this sucker too, even though I'm still expecting initation between 00Z and 03Z. GFS and NAM model soundings/hodographs remain frighteningly good for nocturnal tornadoes through midnight, given discrete storms. With storm motions of between 40 and 55 kts (probably closer to the latter), this is going to be a tough one... so I'll keep my expectations low.

 

[Mike Peregrine]

Wow - those are some POWER parameters. If something does break the cap in western OK, I would want to be there too. I was just about to post the forecast storm motion, but Andy beat me. NAM forecast skew-t has storm motion closer to 40 kts, but yeah - don't count on it. I'm not really into frighteningly fast tornadoes screaming toward me at night (I've tried it already), but yeah - if a person could chase tomorrow evening, I'd say take a chance and see what happens. Alex' target in western OK looks pretty solid. Hopefully the cap will be forgiving.

Edit - by the way - I noticed last night that there was ambient light well after 7:00 p.m. It really surprised me, but you may be able to see something out there. And hey ... extended DST is just around the corner.

 

[Justin Walker]

NAM forecast skew-t has storm motion closer to 40 kts, but yeah - don't count on it.

I believe if storms go up around dusk and become tornadic, then the storm motions will be around 40 kts, but if they are not discrete and tornadic, then they might be approaching the 55 knt speeds. Either way, I will be there to find out.

 

[scott r currens]

I am thinking about heading to W KS Friday night with the hopes of catching some lightning, possibly a LT supercell, and a tornado if I am very lucky.

Scott Olson wrote:

All indications certainly look favorable for the intial storm-mode to be supercells, even at 11pm. The big question is just how elevated these storms will be? Since we are talking about a 60kt LLJ and even higher moisture rich air being advected in, I would suggest that mixing potiental as a result of the strong low level winds will help keep the BL together and the tornado potential should continue to 9z. Just think of 3/11 and some of the other 2006 pre-event nights. In these cases the nocturnal tornadic supercells raged onwards towards midnight, thanks to the strong low level winds and increasing vertical wind shear from the approaching system. All caveats aside (certainly some noteable ones like initial moisture and lower probabilities of daytime initiation). I should note, I'm bias as I enjoy night chasing almost as much as daytime chasing (it's a different experience really).

I am in agreement with Scott Olson's analysis, but I like the area of west central Kansas a little better than NW OK. If the models are correct, at 6Z we could have very high instability for a LT supercells environment. Of course I can come up with a dozen reasons why I shouldn’t chase a nighttime setup in February but it puts me in position for CC Saturday. Yes, I am getting stir-crazy. LOL!

Scott C

 

[Tyler_Costantini]

A Group of us from SE Kansas will be headed out Joey, Chris and I Tyler Costan tini.

Target: ICT so we can use I35/135 to get into postion.

We should be in place near ICT at or before 10:00AM CST

Spotter Nettwork will be call KB0PQP we will be monitoring 146.55.

I'm looking for the best chances between DDC and AMA See you on the plains.