2004-05-22 FCST: OK/KS/MO/IA Area

[Jeff Snyder]

We FINALLY get some good mid-upper level flow in the southern plains on Saturday, as evidenced by ETA forecasts of 40-55 kt 500mb flow and 60-80kt 250mb flow from TX panhandle to nw MO. Additionally, flow at all levels is pretty good, especially relative to many of the "setups" this year thus far. So, from a shear standpoint, things look very good... HOWEVER, the ETA insists on mixing out much of the good low-level moisture across OK/southeastern KS on Saturday... While we still have Tds in the mid-upper 60s (70s seems to be confined to far ne KS, nw MO, and sw IA), this lack of good moisture in most of KS/OK does two things: it limits our surface-based instability, and it gives us an insurmountable cap. IF we can get some good low 70 Tds in OK, it would likely give us very strong instability and it would help decrease CINH, which is unbreakable per latest ETA (I'm up for anyting that'll shift our parcel trajectory to the right on a SkewT LOL)... Granted, it is important to remember that we are 72 hrs out, but it's a good sign to have at least the kinematics in place for a more typical synoptic-scale outbreak possibility...

Right now, points south of KS City look to be capped off, but there still may be good action north of the cap, in IA and se NE perhaps...

 

[Mike Hollingshead]

Personal target as of 12z Thur would be probably Grand Island.
http://www.wxcaster2.com/CENTRAL_ETA_SFC_S...INDSLI_60HR.gif
Very nice warm front to play on Saturday.
http://www.wxcaster2.com/CENTRAL_ETA_SVR_C...HSWEAT_60HR.gif
Some pretty nice shear along the warmfront of course.
http://www.wxcaster2.com/CENTRAL_ETA_500_G...NDVORT_60HR.gif
35-40knts should be more then enough for supercells with the backed low level flow. Interesting disturbance for down along the dryline if it can help break the cap down there. I'd rather play the area north of the dryline bulge. Looking back at the sfc/li's that is one heck of a dryline bulge. Doesn't appear to be one of those so-so bulges...that looks like a BULGE with strong sw winds behind it. Looks like Grand Island to Salina or Grand Island to Omaha. Favoring the Grand Island area here.
http://www.wxcaster2.com/CENTRAL_ETA_700_G...WINDRH_60HR.gif
700 Temps doable.
http://weather.cod.edu/forecast/ETA/etaUS_...500_rhum_54.gif
http://weather.cod.edu/forecast/ETA/etaUS_...500_rhum_60.gif
Nice mid-level dry punch.
http://weather.cod.edu/forecast/ETA/etaUS_..._1km_hel_60.gif
I would not want to drive away from this region of better LCLs and low level helicity for some other target in KS along the dryline. I'd say Sat could be rather big. This looks WAY better then Wed ever looked.

Mike

 

[Kevin Scharfenberg]

My concern is that the numerous MCSs over SD/IA and surrounding areas tonight and Friday night will reinforce the cold air on the north side of the warm front, and it will be quite hard to clear out the grunge with such a strong cap. The dryline looks capped for now, but must keep an eye out for a "strong-enough" vort max in the strong flow.

It will probably turn out to be a decision to play on the warm front where storms are more likely but may become quickly elevated above cold grunge... vs. a play on the dryline where initiation is unlikely.

 

[Billy Griffin]

I am speaking on behalf of us "southern plains chasers"... I guess. I sure hope the dryline is able to get active, the cap break, and it all just go crazy with tornadic, slow-moving cells a plenty.

I have a couple coming out to chase with me this weekend, and it sure would be nice for them, for me, heck everybody !! :lol:

I think we all (down here) would like to see something close to home where we don't have to spend a thousand dollars in gas driving to South Dakota. Since March 27th, the south plains dryline has been shut off like OPEC's ideas of lowering fuel costs !!!

Let's hope for a fun day for everyone on Saturday !!

 

[Anonymous]

Southern plains chaser too!

As one part of the "couple" coming out with you this week, I hope we have some moisture to work with too. Coming out of New Orleans heading up there it looks awfully dry!

Dad and I can't wait to meet up with ya.

 

[Billy Griffin]

Looking forward to meeting up with you guys this coming weekend !!
One of you please email me to let me know your updated plans.

Regards,
Billy Griffin

** Still looking better & better for Saturday on into next week !!!

 

[Austin Ivey]

After glancing at the 0z eta run, I will probably play the 283 corridor between Dodge City and I70. Going by current model forecasts this will put me in play with the dryline. As Kevin stated, initiation along the triple point where the warm front will most likely lie further north in NE has greater chances of actually getting storms to fire, especially considering our recent experiences with the CAP due to unusually strong subtropical ridge in the SP (IOW you need the dynamics).

Nonetheless, I can't make it all the way to NE on Sat. so I will have to play the DL regardless of EML/CAP and conv. possiblities further north.

DDC AFD from this pm sounded somewhat optimistic for Sat:

"THUNDERSTORM CHANCES ON SATURDAY SHOULD BE A LITTLE BETTER AS THE MID LEVEL WARM LAYER WILL BE NOT AS PRONOUNCED AND A MORE SIGNIFICANT UPPER LEVEL SHORTWAVE TROUGH APPROACHES THE REGION. "

Lets hope that UL shtwv trgh can introduce some cooler 700 temps to the target area.


EDIT: I'm likin this:
http://www.rap.ucar.edu/weather/model/gfs0...2hr_500_wnd.gif

 

[Billy Griffin]

Well, I "jinxed" it again. Looks like SPC's confidence in the DL having any activity has all but gone. I think there's no breaking down this "death ridge" and CAP we've had all year long, so I'm chalking this year down as one that, umm... "sucks" !!

Looks like any play will be on TP, or on frontal boundary of North-Central Kansas on east. Maybe (maybe) if we're lucky, initiation will fire around the Dodge City - Hays - Russel area and trek east. Hopefully it won't mean another drive to Michigan.

Wouldn't be so bad if fuel prices weren't so outrageous !! Plus, for those of us living further south, it's just a big pain in the a$$ to have to spend the entire day driving. Yep, that's part of chasin', but every outbreak being way up north has gotten old.

To me, as of now, looks like a Kansas play, maybe even into southern Nebraska... just have to wait and see. But one thing for sure, the dynamics won't be on the DL, and the CAP will be impossible to break.

Now... now that I've said that, everyone go to dryline. If I go north, it WILL fire south. See, it's a rule of nature. Where I'm at, storms are not. It's all part of Mother Nature's little "plot".

Heck, let's just all have fun and see what happens. Look at it this way, at least we're helping out those struggling poor folks in the oil and gas industry !!!

 

[Austin Ivey]

Don't give up hope on the DL yet Billy. I realize SPC yanked there slt risk this morning but the potential event is still 36 hrs away and things can and often do change dramatically. As you probably know, CAP magnitude forecasts are almost never resolveable this far out; especially with the sub-tropical ridge moving farther east and a trough moving in from the west.

From OUN this am:

"500MB WINDS PROGGED TO
INCREASE TO 30-35 KT BY THIS EVENING AND TO AROUND 50 KT SAT.
QUESTION IS IF THERE WILL BE ANY DRYLINE STORMS...AS CAP WILL REMAIN AN OBSTACLE. 700 MB PROGGED TO WARM TO 13C OR MORE THIS AFTERNOON THEN COOL SOME TO AROUND 11-12C SAT. IMPRESSIVE MID-LEVEL LAPSE RATES AOA 8C/KM IN 700-500 LAYER AND DIABATIC HEATING W OF DRYLINE EXPECTED TO ALLOW ISOLATED STORMS TO DEVELOP ALONG DRYLINE DURING MAX HEATING. "


So an 11-12c CAP (which probably will change) is borderline "non-breakable" for late may. OUN may be way too far south of the stronger dynamics and shortwaves rotating around the trough so, if the DL is your only option, a play farther north (DDC, I-70) might be better.

As far as dynamics go, I've been reminded by much more experienced chasers than myself that keeping an eye on the TCU and white sands NM ua profiler when playing the DL in KS/OK/TX is very important. Jet streaks or other meso/microscale dynamic features the models might miss or not been able to resolve might be seen on the ua profiler and can give the target area the "push" needed to overcome a strong CAP given the appropriate flow trajectory.

Because this potential event falls on a Saturday, I will most likely be out there regardless or early morning pessimism/CAP forecasts. Like Kevin S. said yesterday though, the region with the best chances for conv. init. is still central NE which is out of reach for me.

 

[Shane Adams]

Latest ETA run showing 10.6c at h7....that doesn't concern me. It's the 28c progged at h85 I'm worried about. That's thermonuclear.

 

[Austin Ivey]

Geez....

What location are you speaking of Shane?

 

[Austin Ivey]

Just an FYI for those of you awaiting the cool down of 700 temps. Here in Los Alamos there is a weather observing station at 10,360 feet. This elevation places it approximately at 700mb. The temperature has dramatically cooled from yesterday when I saw a ~15C temp at that elevation. As of a few minutes ago, the temp. was only 8.8C. Hopefully these more reasonable temps will be spreading east for manana!

 

[Shane Adams]

Originally posted by Austin Ivey
Geez....

What location are you speaking of Shane?

Everything west of 35 and south of 70...

 

[Billy Griffin]

I won't really "give up" on the dryline, but honestly, I just don't think the CAP is breakable at all. I was so hoping that something would get going this year close to home (TX Panhandle area), but it looks like our northern neighbors are getting all the action this year.

I'm certain we are probably close to RECORD low numbers for tornadoes at this point in the year. Yeah, we've had a few. But if you think about it, the only REAL days I can recall panning out for me is March 27th in Oklahoma and May 12th in Harper County, KS.

I know others have had success in other parts of "the alley", but it just hasn't transpired into an active year (IMO). I know, s### happens, but to me it's not worth setting around in Oklahoma watching a sunny day vs. driving a little bit where convection is almost guaranteed to fire.

For me and my group coming to join me, if they get here in time that is, I'll say Saturday calls for a drive up to at least I-70, maybe play from there. Initial target = get to Hays ~ Russel before 3pm, then pick and choose from there.

I just don't think the DL will go. Cap is holding until November !!!

 

[Jeff Snyder]

Yeah, I wouldn't put all your belief in SPC Day2 right now... Both OUN and ICT offices are much more optimistic regarding convective initiation than what the SPC is saying...

There is a nice area between the dryline and the western edge of the cap that I think has potential. Shear will be quite nice (check out the low-level jet...), though instability will be slightly limited by the mixing out of higher dewpoints. Whatever the case, I do think there will be a few isolated / widely scattered supercells between, say, Clinton and Salina tomorrow... Definately worth watching... Tornadic threat from these may be mitigated by high LCLs, but I think the situation will take a heads-up turn if we can keep Tds near 70...