Central/Western Summer Medium/Long Range Discussions

[andyhb]

EDIT: 00z ECMWF completely squashes the Rio Grande Valley ridge from previous runs and allows for another round of setups late next week... very impressive if it's the beginning of a real trend.

 

12z GFS/Euro both seem to indicate the potential for a prolonged period of western troughing succeeding whatever happens early next week, pretty impressive look as we head into the period where instability is almost always available.

[cyclone77]

Unfortunately still about 5 days out, but the 00z GFS looks pretty nice for Tue the 3rd.  00z GFS indicates an ultra-rare well-timed short wave entering the Plains Tue afternoon.  Shear profiles over northern Kansas look very nice amid strong instability.  Verbatim it would likely be a decent chase setup.

[Thunder Road]

It seems most of the focus has been on Monday and Tuesday, but even Sunday looks decent.  GFS sounding from OFK 0z Mon:

 

 

BUFKIT has exactly 300 m2/s2 of 0-3 km helicity at this point.  A bit of CIN to worry about, but verbatim, the parcel would just barely slip past the isothermal layer around 700 mb.

 

GFS breaks out isolated precip along the boundary from FSD all the way down through central Kansas, and has for several runs now.

[Quincy]

It seems most of the focus has been on Monday and Tuesday, but even Sunday looks decent.

A bit of CIN to worry about, but verbatim, the parcel would just barely slip past the isothermal layer around 700 mb.

GFS breaks out isolated precip along the boundary from FSD all the way down through central Kansas, and has for several runs now.

GFS shows >2500 J/kg SBCAPE paired with 36-50kt bulk shear from central KS up into NE. Sure, some CIN is there, but still a decent looking setup with at least some potential.

[Stebo]

It seems most of the focus has been on Monday and Tuesday, but even Sunday looks decent.  GFS sounding from OFK 0z Mon:

 

 

BUFKIT has exactly 300 m2/s2 of 0-3 km helicity at this point.  A bit of CIN to worry about, but verbatim, the parcel would just barely slip past the isothermal layer around 700 mb.

 

GFS breaks out isolated precip along the boundary from FSD all the way down through central Kansas, and has for several runs now.

 

12c at 700mb is a decent cap, I would be cautious of the GFS showing convection with that.

[tornadotony]

12c at 700mb is a decent cap, I would be cautious of the GFS showing convection with that.

12C with June sfc Ts may not be a complete buzzkill.  That's certainly not the most overwhelming cap in the world on that sounding.  If the GFS is convecting, then it may be signifying some sort of larger-scale forcing for ascent.  Additionally, the cap is located pretty high aloft on that sounding.  Why is that important?  It tells me you're going to have room for some vigorous Cu/TCu growth underneath it.  Evaporation at the top of that vigorous Cu/TCu field may be enough to break that cap.  IIRC (and I'm almost certain I do since I was out chasing at the time), Bowdle featured a very similar thermodynamic environment, with a strong-ish cap but rather high up.  I got to watch 3 consecutive towers grow, cap, and fail before the tower that became the Bowdle beast formed.  Fascinating.

[nrgjeff]

June Boom in effect next week. Since I'm concentrating on Day 4+ will post in this thread. Sunday should feature a good chase day with multiple boundaries. Monday or Tuesday could be a down day. Tuesday or Wednesday could go in Kansas again. Thursday and Friday may be Panhandle Magic. No one day is excellent; however 5 of 7 days are chasable. One would expect to see 1-2 tornadoes next week if flexible and willing to drive a lot. No compromise on targets. Must follow boundary intersections.

 

Round 1: Sunday is complicated, but should hopefully spread out chasers. SD/NE/KS/WY/CO all in play. Triple point may be cell of the day, but also could be messy HP chaser-con. WF may offer a chance or two. DL forecast to go despite cap. If OFB (Sat night rain) intersects DL low level turning would be good down there. Otherwise turning will be excellent on WF. Upstairs jet stream is only OK but LLJ looks good. Finally Plan B could be upslope land behind the front if messy east and/or cap bust south. Monday might go in the central Plains but it looks like a rest day right now.

 

Round 2: Midweek models disagree on Tuesday or Wednesday, but a short-wave is forecast to eject through Kansas. Strongest upper jet energy is forecast this midweek day. GFS is Tuesday but Euro is Wednesday. The day the short-wave comes out the LLJ appears to be adequate. Look for boundary intersections.

 

Round 3: Late week could be Panhandle Magic. Final jet streak may teardrop in the Southwest. Normally that is not as good as coming straight out; but, we saw a teardrop deliver just a few days ago. Plus the surface front will be down there enhancing upslope flow. EDIT: Thursday shown more Front Range on 12Z Euro; continue Friday Panhandle. Teardrop issue resolving...

 

Then Days 9-10 both models still have stuff going on in the Lower Miss Valley. No comment on that yet. Terrain goes to heck into banjo land. Backing up, High Plains may go Fri/Sat. Bottom line: Several days in the next 10 will be chasable. While none screams out, odds favor 1-3 tornado bookings if one can spend the whole week in the field. Cheers!

[Stebo]

12C with June sfc Ts may not be a complete buzzkill.  That's certainly not the most overwhelming cap in the world on that sounding.  If the GFS is convecting, then it may be signifying some sort of larger-scale forcing for ascent.  Additionally, the cap is located pretty high aloft on that sounding.  Why is that important?  It tells me you're going to have room for some vigorous Cu/TCu growth underneath it.  Evaporation at the top of that vigorous Cu/TCu field may be enough to break that cap.  IIRC (and I'm almost certain I do since I was out chasing at the time), Bowdle featured a very similar thermodynamic environment, with a strong-ish cap but rather high up.  I got to watch 3 consecutive towers grow, cap, and fail before the tower that became the Bowdle beast formed.  Fascinating.

 

Yeah that is true, I guess I am a bit conservative when it comes to capping calls especially when it is right on the cusp like 12c. I will say it would be something to monitor if like you said the GFS is convecting due to ascent or if the models trend cooler at 700mb to limit capping some.

[Thundersnow12]

12C with June sfc Ts may not be a complete buzzkill.  That's certainly not the most overwhelming cap in the world on that sounding.  If the GFS is convecting, then it may be signifying some sort of larger-scale forcing for ascent.  Additionally, the cap is located pretty high aloft on that sounding.  Why is that important?  It tells me you're going to have room for some vigorous Cu/TCu growth underneath it.  Evaporation at the top of that vigorous Cu/TCu field may be enough to break that cap.  IIRC (and I'm almost certain I do since I was out chasing at the time), Bowdle featured a very similar thermodynamic environment, with a strong-ish cap but rather high up.  I got to watch 3 consecutive towers grow, cap, and fail before the tower that became the Bowdle beast formed.  Fascinating.

 

Correct and remember that too as myself and CoD drove north. I still can remember what vis sat looked like that day. 

[andyhb]

Also on the plus side, the CFSv2 SCP product is becoming quite active through June and even into July possibly.

 

http://wxvu.net/spc/cfs_scp/

[Chicago Storm]

Tomorrow and Thursday in MT/ND/SK/MB and then Monday in the Plains are really the only interesting looking days at this point.

Yesterday wasn't that great. Today and Monday don't look that great either now.

 

The GFS likes Tues and the ECMWF likes Wed as the higher potential day(s).

[andyhb]

Yesterday wasn't that great. Today and Monday don't look that great either now.

 

The GFS likes Tues and the ECMWF likes Wed as the higher potential day(s).

 

Beyond Monday is almost non-stop severe potential on the 18z GFS from the Plains eastward into the Midwest/OV as a series of shortwaves rotate around the Rio Grande high, almost like a ring of fire pattern except with ample mid level flow available.

[Chicago Storm]

Beyond Monday is almost non-stop severe potential on the 18z GFS from the Plains eastward into the Midwest/OV as a series of shortwaves rotate around the Rio Grande high, almost like a ring of fire pattern except with ample mid level flow available.

Yea...The other days would have some sort of potential as well.

 

Still though, it looks like Tue or Wed has the highest potential at this point... Though timing may obviously change yet again.

[andyhb]

Great rotation near Kipling, SK.

[andyhb]

00z Euro/UK at 144 hrs synoptically have many of the ingredients in the Central Plains for a pretty substantial tornado threat with a potent LLJ feeding into KS/NE/IA/MO and a robust s/w trough ejecting with corresponding strong surface cyclogenesis. Looks to potentially continue further east on the next day, this is a pretty productive looking pattern setting up here for the first week of June.

 

At the same token, the 00z GFS shows a pretty nasty looking upslope setup at 120 hrs and then the next day looks potentially explosive as the s/w trough emerges with a near 70 kt 500 mb max to go along with a crazy EML with near dry adiabatic mid level lapse rates.

[Chicago Storm]

12z GFS with a solid 4 days of good potential Tue -Fri.

[Thundersnow12]

12z GFS with a solid 4 days of good potential Tue -Fri.

 

Think you could include Sat this run too even though it's well out there .That secondary trof coming in late week looks quite nice. 

[brettjrob]

Yeah, the period from Sun-Fri could potentially be a partial save of the chase season and at least lift us definitively out of 1988/2006 territory. No single day is a synoptically-evident biggie (yet), but barring capping issues, there's a lot of potential spread out over many days. I love patterns like this.

[Thundersnow12]

Just imagine if we had good gulf trajectories. It's all easterly flow across the gulf next week north of that stupid low out there. 

[Chicago Storm]

Think you could include Sat this run too even though it's well out there .That secondary trof coming in late week looks quite nice. 

Yea, Sat as well.

[andyhb]

I'm interested to see what the moisture does given the recent rainfall over the drought areas considering the 12z GFS showed some pretty ugly looking mixing going on at 180 hrs with the setup there (thanks to a slug of dry air coming from the Atlantic). The effects of the gyre in the BOC are going to be interesting, as thundersnow mentioned, not exactly ideal moisture trajectories the further out we go.

[ilstormchaser]

I am going to be out chasing Tuesday-Friday and am trying to decide if I should head out for Tuesdays event or hang back home in IL for Wed and then go out for Thursday, Friday, and possibly Saturday if its close to home. decisions..decisions. Guess I will just have to wait until the 12z data Monday.    

 

[Chicago Storm]

12z GFS with a solid 4 days of good potential Tue-Fri.

ECMWF was more Tue/Wed.

[Chicago Storm]

I am going to be out chasing Tuesday-Friday and am trying to decide if I should head out for Tuesdays event or hang back home in IL for Wed and then go out for Thursday, Friday, and possibly Saturday if its close to home. decisions..decisions. Guess I will just have to wait until the 12z data Monday.    

Yea, this could end up being interesting.

 

Go from KS/NE on Tue, to IL/IN on Wed, then back to KS on Thur.

[andyhb]

Southern half of NE (especially the SE part) looks explosive on Tuesday on the 18z/00z GFS, I've been checking out some really impressive soundings at 21z there for the past few minutes. Cap is close to breaking in NE KS within a ridiculous parameter space towards 00z Wed as well. The setup itself (verbatim) is rather reminiscent of 5/22/04 (Hallam).

[Minnesota Meso]

Not sure where to put this so I decided to put here. If this forecast should pan out from the latest UKIE you may want to alert anyone you know that is going to be in the BWCA, it is a hot link so things could change, I hope there is no micro burst with dying cells.

 

[andyhb]

The pattern shown by the GFS/Euro/affiliates is as solid as we've seen in awhile in June (many people just don't realize how hard it has been to get 50-60 kts of mid level flow overlapping a warm sector this time of year since 2011, aside from 6/12 last year). Even 2011 had some issues in that department apart from the strange, pseudo-cold core 6/20 setup in KS/NE with explosive instability. The only thing somewhat lacking is a more obvious outbreak setup on one of the days (although that could still change), but there appear to be plenty of chances for a significant event(s) as the EML plume becomes established and strong instability becomes prevalent across the Central US with an active LLJ.

[brettjrob]

The pattern shown by the GFS/Euro/affiliates is as solid as we've seen in awhile in June (many people just don't realize how hard it has been to get 50-60 kts of mid level flow overlapping a warm sector this time of year since 2011, aside from 6/12 last year). The only thing somewhat lacking is a more obvious outbreak setup on one of the days (although that could still change), but there appear to be plenty of chances for a significant event(s) as the EML plume becomes established and strong instability becomes prevalent across the Central US with an active LLJ.

 

Agreed. The last several years have completely skewed people's perception of June on the Plains. Even if several or most of the upcoming days with potential come through (most will probably be an a relatively isolated basis if they do), we'd probably still need a few more decent events through the rest of the month to match climo. In comparison to June 2011-2013 (throwing out 6/20/11), though, the next week may appear apocalyptic.

[andyhb]

00z Euro is also looking rather volatile across southern NE/perhaps northern KS depending on the extent of capping on Tuesday. A near 70 kt WSW 500 mb jet max ejects right across that area with a southerly low level jet on top of strongly backed surface winds even well into northern KS despite the warm front being near/north of I-80 from the looks of it.

 

Edit: To add on, there appear to be other days with good potential such as 168 in W TX and then 192 as the s/w trough there ejects NE and interacts with the northern stream.

[Minnesota Meso]

Per the 5/31 0z run of the Euro.  It looks rather interesting in the 8-10 day forecast as the southwestern stream energy tries to phase with the energy coming in from the NW, if that should happen it could get very dicey up here.  As a matter of fact the model shows the 540 thickness line just north of the border, which would suggest a very strong temp gradient.  I would guess the stronger storms should stay over IA, but of course at this time forecast confidence is very low.