Major severe weather outbreak in the southern plains - 04/26/2016 - 04/29/2016

a reply to: TechniXcality

And just to give you all an idea of what kind of events 5000 j/kg of cape produces here's a link and description,



WIKI

Two notable days for severe weather exhibited CAPE values over 5 kJ/kg. Two hours before the 1999 Oklahoma tornado outbreak occurred on May 3, 1999, the CAPE value sounding at Oklahoma City was at 5.89 kJ/kg. A few hours later, an F5 tornado ripped through the southern suburbs of the city. Also on May 4, 2007 CAPE values of 5.5 kJ/kg were reached and an EF5 tornado tore through Greensburg, Kansas. On these days, it was apparent that conditions were ripe for tornadoes and CAPE wasn't a crucial factor. However, extreme CAPE, by modulating the updraft (and downdraft), can allow for exceptional events, such as the deadly F5 tornadoes that hit Plainfield, Illinois on August 28, 1990 and Jarrell, Texas on May 27, 1997 on days which weren't readily apparent as conducive to large tornadoes. CAPE was estimated to exceed 8 kJ/kg in the environment of the Plainfield storm and was around 7 kJ/kg for the Jarrell storm.

originally posted by: GBP/JPY
yep, yep.....I'm a trained meteorologist......two years of aviation weather, anyway.......does that count?

every year it does this . the tornados go up north to Oklahoma.....here in Dallas.....it's always the same days.....May 3rd or 4th....clobbered good like.....I mean it, too
I've tracked it since the Branniff air disaster on May 3 68 or 69.......enough to knock an Electra out of the sky near Corsicanna

This is what ticks me off. My bday is May 1st and I can't tell you how many times I've had plans cancelled because of the severe weather. It seems every other year there is a tornado coming through the DFW area. I just can't make plans anymore so I always wing it on my 'special' day. Sigh...

Don't get me wrong. I love our crazy Texas weather but sometimes it's just a little too much.

Stay safe, everyone!

a reply to: GBP/JPY

I think you have a neat job and many of us rely on you to help keep us safe.

I've seen many tornadoes and thought about becoming a storm chaser but I've never followed through.

Thanks again, Technix, for putting this alert out. I wasn't aware of another serious storm system coming.

As long as I can get my lawn done this weekend...

a reply to: TechniXcality

I used to be a 25170 years ago. Wondering if you were as well ( or whatever they call it now)


ETA: I did flightline obs for a while then spent a few years @ AFGWC in Offut.

That latest model puts the higher dew points pretty far up north toward my neck of the woods. Let's hope that dry line doesn't roll up north too.

NWS discussion Norman Oklahoma

AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORMAN OK 332 PM CDT THU APR 21 2016 .DISCUSSION... A MID AND UPPER LEVEL LOW OVER IOWA WILL MOVE EASTWARD THROUGH SATURDAY...MEANWHILE...A RIDGE OVER THE WESTERN UNITED STATES BUILDS INTO THE GREAT PLAINS. THE MAIN RESULT WILL BE DRY WEATHER WITH WARMER TEMPERATURES. SURFACE WINDS WILL INCREASE LATE FRIDAY AND ESPECIALLY SATURDAY AS A TROUGH MOVES FROM THE INTERMOUNTAIN WEST INTO THE CENTRAL AND NORTHERN ROCKIES. A FEW STORMS MAY FORM NEAR A DRYLINE IN THE TEXAS PANHANDLE LATE SATURDAY AFTERNOON AND EVENING...AND MAY MOVE INTO NORTHWEST OKLAHOMA BEFORE WEAKENING. AS THE TROUGH MOVES ACROSS THE CENTRAL AND NORTHERN PLAINS ON SUNDAY...WIDELY SCATTERED STORMS MAY FORM IN NORTHERN OKLAHOMA DURING THE LATE AFTERNOON/EVENING. INSTABILITY AND SHEAR WILL SUPPORT SUPERCELLS WITH LARGE HAIL AND DAMAGING WINDS. MAINLY DRY WEATHER IS EXPECTED ON MONDAY...HOWEVER BREEZY SOUTH WINDS MOST OF THE DAY WILL AID IN BETTER GULF MOISTURE TRANSPORT INTO THE SOUTHERN PLAINS. A MUCH STRONGER SYSTEM/TROUGH IS FORECAST TO INFLUENCE THE REGION ON TUESDAY. DIFFERENCES IN DRYLINE POSITIONING AND TROUGH TIMING REMAIN...BUT CONDITIONS MAY BECOME FAVORABLE FOR SUPERCELLS WITH TORNADOES...DAMAGING HAIL/WINDS. OVERNIGHT TUESDAY INTO WEDNESDAY...MUCH DRIER AIR WILL MOVE INTO WESTERN AND CENTRAL OKLAHOMA BEHIND A COLD FRONT. THIS SHOULD LIMIT STORM/SEVERE CHANCES TO SOUTHEAST OKLAHOMA. SEVERE WEATHER CHANCES WILL INCREASE AGAIN BY THURSDAY/FRIDAY OF NEXT WEEK AS ANOTHER TROUGH APPROACHES FROM THE SOUTHWEST. BOTTOM LINE...IT`S LATE APRIL IN OKLAHOMA AND NORTH TEXAS AND SEVERE STORMS OFTEN DEVELOP. AT THIS TIME...SUNDAY AND TUESDAY APPEAR TO BE THE FAVORED DAYS FOR SUCH WEATHER OVER THE NEXT 5 DAYS.

a reply to: texasgirl

You are most certainly welcome, I plan on chasing next week perhaps I'll get some good video for all of you, of course I get excited when I see a week like next week, however I also am very cognizant of the dangers.

a reply to: quercusrex

No sir, I'm just an avid weather watcher, and storm chaser when time permits, I'm considering going back to school to be a professional meteorologist, it's a passion I love might as well get paid for it.

a reply to: TechniXcality
Keep up the good work.

Thank you TechniXcality for keeping everyone informed! I think it is a noble thing that you are doing here. If one person is made aware of the (possible) danger ahead - whom may not have otherwise - it makes it all worthwhile, imo.

Although, I live in an area where tornado outbreaks are not as numerous as in the plains - they do happen here (mid-south).

Thus, I've always kept an "eye to the sky", as a particularly large twister was about two miles from my old house way back in 2008 during the "Super Tuesday" outbreak. (Wiki Link about the '08 Super Tuesday outbreak for those that are unfamiliar)

Hearing, and even more disturbingly FEELING the ground rumble from a high-end EF2, from that far away, ignited a spark of fascination within me, as well as gaining an instantaneous massive amount of respect for these storms. It is hard for me to fathom the power that these storms posses. If an EF2 was that loud, and literally made the ground shake and vibrate from well over two miles away - I can only imagine what it is like with an EF5. And honestly, I hope I never have to personally find out. i'm certainly "down" with just experiencing those classes of tornadoes from YouTube videos! (Or maybe at a safe distance in a non-populated area).

Ok. There I went and rambled on (storm stuff can do that to me!)

Anyway, the original intent of this message, again, is to thank YOU, TechniXcality for everything you do here in this thread, and elsewhere!

Rock on, my friend!
~JM2

a reply to: TechniXcality

Do you know any of the folks on the Texas Storm Chasers blog / facebook page?

Just curious cause they'd be some very like minded folks. Let me know when you get a chance to check out the updated models, kind of looks like on Tuesday some folks are predicting the absolute worst will be a little north of DFW, but we're still in the 'moderate' zone for severity... just checking in while I sit here sip suds and watch playoff hockey!

Thanks for your analysis here lots of us appreciate it Tex!

a reply to: SonOfThor

I communicate with several professional Mets on a forum called storm2k, I also storm chase with a few of them. I do not know of that facebook, as I don't use facebook though it seems everyone does, so I ought to

Yes there is a negatively tilted upper level disturbance with the best forcing forecasted to be just north of north central Texas in Oklahoma. However, the models are currently showing that the cap will indeed break even this far south which will allow for powerful supercells capable of producing long track Torandoes, and grapefruit sized hail! this is a widespread outbreak spreading all the way into Kansas, and also a multi day event, so we are concerned about Tuesday night into Wednesday and even Thursday and Friday, the pattern looks to remain unsettled, but it is that time of year.At the 00z model guidance I will update further. Also you are most certainly welcome this is what I love to do cheers brother

Here is the latest from Accuweather.

"Of the two days, Tuesday has the greatest potential to produce numerous tornadoes, including some strong [wedge] tornadoes that could be on the ground for an extended period of time," Gagnon said.

At this time, the area at greatest risk for violent storms on Tuesday is forecast to extend from central Texas to a large part of Oklahoma, Kansas and Missouri. However, the area could change somewhat, depending on the track of a storm that will move out of the Rockies on Monday night.

This has already shifted quite a bit since your first post. It's now potentially threatening my neck of the woods, and a good chunk of my friends and family are in the red zone out in Kansas.

originally posted by: ketsuko
Here is the latest from Accuweather.

"Of the two days, Tuesday has the greatest potential to produce numerous tornadoes, including some strong [wedge] tornadoes that could be on the ground for an extended period of time," Gagnon said.

At this time, the area at greatest risk for violent storms on Tuesday is forecast to extend from central Texas to a large part of Oklahoma, Kansas and Missouri. However, the area could change somewhat, depending on the track of a storm that will move out of the Rockies on Monday night.

This has already shifted quite a bit since your first post. It's now potentially threatening my neck of the woods, and a good chunk of my friends and family are in the red zone out in Kansas.

Good God...That's a little frightening. We don't need another wedge tornado here. We're still cleaning up from the Christmas one!

a reply to: texasgirl

Well, it is Accuweather, but in this case, they are not disagreeing with the rest of what I am seeing. It does look like the potential is spreading north and a bit east as time goes on.

Here's our local weather blog. Joe and Mike are pretty good at pinning down what's going to happen in our area. They aren't sold on Tuesday just yet. It's still too early to say where exactly things will set up.

The day I’m somewhat more interested in is Tuesday. There remains significant model differences though how Tuesday will play out locally. How unstable we get…will there be any convection in the morning messing things up for the afternoon.

Here’s what I can comfortably say at this point.

-Severe weather potential will be increasing in the Plains

-A vigorous upper level storm will be coming out of the southern Rockies as the EURO mode depicts for 7AM Tuesday

– The atmosphere will have lots of moisture in it from the surface upwards…our dewpoints here will be a very springy with readings into the 60-65° range.

– a low level jet will be prevalent in the Plains and we may get some thunderstorms even in the morning hours on Tuesday…how will that play into things for the later afternoon and evening.

– The atmosphere should get VERY unstable in parts of the Plains. Where this sets up though is still a question. With that said a rather well defined dry line will establish itself in the favored areas of western OK and western KS. Right now I’m leaning toward the best instability and the potential for the “bigger” storms to be out towards south central and SE KS and into central OK

– For the KC area…our best rain chances will be Sunday evening into early Monday AM…then again Tuesday into early WED AM…after that we should dry out.

a reply to: ketsuko

Thank you for that, and indeed Kansas is in the cross fire, which is why I made this thread because of how wide spread this outbreak could be and because of the potential for deadly and damaging supercells. Here's the latest from SPC they too will update in about 8 hours, however latest model guidance is trending In a worse direction so we will have to keep our eyes glued to the models..

. ...DAY 5/TUESDAY... THE GREATEST THREAT FOR SEVERE WEATHER APPEARS TO BE ON DAY 5/TUE. DETERMINISTIC AND ENSEMBLE GUIDANCE CONTINUES TO BE IN GOOD AGREEMENT...INDICATING INGREDIENTS IN PLACE FOR A POTENTIAL SEVERE WEATHER OUTBREAK ACROSS PORTIONS OF THE SRN/CNTRL PLAINS TUESDAY AFTERNOON/EVENING. A STRONG UPPER TROUGH OVER THE WESTERN STATES WILL BECOME NEGATIVELY TILTED WHILE PIVOTING EASTWARD TOWARD THE PLAINS. A 60+ KT MIDLEVEL JET WILL OVERSPREAD NM INTO WRN TX/OK AND KS BY TUESDAY AFTERNOON. AT THE SURFACE...A LEE CYCLONE WILL DEVELOP OVER ERN CO AND SHIFT EWD ACROSS KS. A SHARP DRYLINE WILL EXTEND SOUTH/SOUTHWEST FROM THE LOW OVER SOUTHWEST KS INTO WRN OK AND W-CNTRL TX. A WARM FRONT WILL BE DRAPED ACROSS NRN KS INTO THE MID-MS VALLEY. SOUTH/SOUTHEASTERLY LOW LEVEL FLOW WILL TRANSPORT MID 60S TO NEAR 70 DEWPOINTS NORTHWARD ACROSS THE WARM SECTOR...WITH MODERATE INSTABILITY IN PLACE BY AFTERNOON. STEEP MIDLEVEL LAPSE RATES AND STRONG...VERTICALLY VEERING SHEAR PROFILES WILL FAVOR SUPERCELLS CAPABLE OF ALL SEVERE HAZARDS INCLUDING VERY LARGE HAIL AND TORNADOES. ...DAY 6/WEDNESDAY... THE SEVERE THREAT IS EXPECTED TO SHIFT EASTWARD ON DAY 6/WED ACROSS PARTS OF THE MIDDLE MS VALLEY TO NORTHEAST TX AHEAD OF THE EASTWARD-ADVANCING SURFACE LOW AND COLD FRONT. CONVECTION WILL LIKELY BE ONGOING WEDNESDAY MORNING ACROSS PARTS OF THE MID-MS VALLEY...BUT GUIDANCE IS IN REASONABLE AGREEMENT THAT THIS CONVECTION WILL SHIFT EAST AND ALLOW FOR SOME AIRMASS RECOVERY BY AFTERNOON. THE AIRMASS WILL REMAIN MORE PRISTINE WITH SOUTHWESTWARD EXTENT INTO SRN MO/AR/SE OK/NE TX AND THE BETTER SEVERE THREAT MAY ULTIMATELY UNFOLD ACROSS THAT AREA. GUIDANCE DOES SUGGEST SLIGHTLY MORE VEERED LOW-LEVEL FLOW...BUT PARAMETERS SHOULD STILL BE FAVORABLE FOR ALL SEVERE HAZARDS. ...DAY 7/THURSDAY - DAY 8/FRIDAY... STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE ON DAY 7/THU...THOUGH PREDICTABILITY IS LOW GIVEN TWO DAYS OF PRIOR CONVECTION ACROSS PARTS OF THE PLAINS/MS VALLEY REGION. GUIDANCE SUGGESTS SHORTWAVE RIDGING OVER THE PLAINS AS THE UPPER TROUGH OVER THE UPPER MIDWEST/GREAT LAKES SHIFTS EASTWARD TOWARD NEW ENGLAND. BETTER MOISTURE WILL LIKELY REMAIN OVER TX AND THE LOWER MS VALLEY WHERE STRONG TO SEVERE STORMS COULD DEVELOP ALONG THE COLD FRONT AND/OR OUTFLOW FROM PREVIOUS DAYS CONVECTION. WHERE THIS MAY OCCUR IS UNCERTAIN HOWEVER. THIS UNCERTAINTY AND MULTI-MODEL VARIABILITY CONTINUES INTO DAY 8/FRI...WITH GUIDANCE DIFFERING IN THE EVOLUTION OF ANOTHER WESTERN TROUGH EJECTING EASTWARD TOWARD THE PLAINS.

A graphic for you all in north Texas..

a reply to: TechniXcality

No doubt, you guys are in for a rough ride down there.