General Weather Discussion - May 2015

[bchris02]

As a meteorologist, that was one of the most ridiculous evolutions of a storm that I've ever seen. It did remind me a bit of 5/31/13 (sans that large/strong of a tornado), but I was back home dealing with a family situation at the time and didn't watch the radar in real-time for most of that event. Still trying to wrap my head around it. Later on in the evening, seemingly random couplets were forming and just being slingshot around the main mesocyclone and dissipating just as quickly as they formed (particularly in the southern half of OKC). I'm confident a lot of investigating and research will be done on this as a case study... pretty incredible stuff. Myself and a bunch of friends couldn't get home last night and wound up sleeping at friends' houses or in our offices... and saw some pretty bad damage around I35/SE44th while driving back home today.

Between all of the rain two nights ago and the insane rains last night, I shudder to think what would happen with more widespread rain over the area today. And I'll be the first to admit that the models did not forecast this well at all. I think the local mets (and SPC) did a pretty good job (sans a few comments on-air that made me cringe) considering the strange evolution of the storm and being on air for 8 hours straight... pretty noble work IMO. But from what I can recall none of the models really forecast anything close to what wound up transpiring last night.

Yesterday morning, the meteorologists were predicting isolated severe weather centered on western Oklahoma. What ended up happening was a major outbreak centered on OKC. It's hard to believe it was a slight risk day and OKC wasn't even included in that risk yesterday morning. I am extremely nervous about Saturday.

Do you know what it is about the H.E. Bailey Turnpike. Why do severe outbreaks so many times happen with supercells going up in SW OK, going up the turnpike into the OKC area impacting Moore?

[venture]

Yesterday morning, the meteorologists were predicting isolated severe weather centered on western Oklahoma. What ended up happening was a major outbreak centered on OKC. It's hard to believe it was a slight risk day and OKC wasn't even included in that risk yesterday morning. I am extremely nervous about Saturday.

Do you know what it is about the H.E. Bailey Turnpike. Why do severe outbreaks so many times happen with supercells going up in SW OK, going up the turnpike into the OKC area impacting Moore?

So much wrong with this post, but I'll respond regardless.

1) What ended up happening was isolated severe weather, roughly 2 storms, that impacted a highly populated area that made headlines likely. That doesn't make it an outbreak alone. Yes we also had some additional tornadoes up in NW OK and of course the bigger show up in Kansas and Nebraska (tornado wise). Major outbreak though? Hardly...at least for us.

2) First off...OKC WAS included in the slight risk at the initial risk outlook put out at 12:55AM. You can read all about here: Storm Prediction Center May 6, 2015 0600 UTC Day 1 Convective Outlook

Why is it hard to believe it was a Slight Risk day...even though it was actually upgraded to enhanced later in the day. We had a complicated setup that could have completely busted out yesterday. Would you be here commenting on how we all would have missed the forecast again if things evolved differently?

Situations evolve and so do forecasts. Early in the day it was noted that SPC was holding the tornado probabilities at 5% because they weren't sure on exact coverage. They did however note that conditions would be supportive of strong tornadoes, so they weren't missing that part at all.

As far as the I-44 being a storm magnet. Why is the intertropical convergence zone one for hurricanes in the Atlantic? More than likely it is just a matter of being in the geographically favored area. Nothing more. Unless you want to start talking indian burial grounds and stuff.

[SoonerBeerMan]

So much wrong with this post, but I'll respond regardless.

1) What ended up happening was isolated severe weather, roughly 2 storms, that impacted a highly populated area that made headlines likely. That doesn't make it an outbreak alone. Yes we also had some additional tornadoes up in NW OK and of course the bigger show up in Kansas and Nebraska (tornado wise). Major outbreak though? Hardly...at least for us.

2) First off...OKC WAS included in the slight risk at the initial risk outlook put out at 12:55AM. You can read all about here: Storm Prediction Center May 6, 2015 0600 UTC Day 1 Convective Outlook

Why is it hard to believe it was a Slight Risk day...even though it was actually upgraded to enhanced later in the day. We had a complicated setup that could have completely busted out yesterday. Would you be here commenting on how we all would have missed the forecast again if things evolved differently?

Situations evolve and so do forecasts. Early in the day it was noted that SPC was holding the tornado probabilities at 5% because they weren't sure on exact coverage. They did however note that conditions would be supportive of strong tornadoes, so they weren't missing that part at all.

As far as the I-44 being a storm magnet. Why is the intertropical convergence zone one for hurricanes in the Atlantic? More than likely it is just a matter of being in the geographically favored area. Nothing more. Unless you want to start talking indian burial grounds and stuff.

Woah, you actually replied to that?!? I thought, "Nah, Venture will just let that pass. No need to comment on something that absurd." I think you actually enjoy it.

Why wasn't the tiger outbreak in Tuttle included in SPC's forecast for the day????

[jn1780]

Yesterday morning, the meteorologists were predicting isolated severe weather centered on western Oklahoma. What ended up happening was a major outbreak centered on OKC. It's hard to believe it was a slight risk day and OKC wasn't even included in that risk yesterday morning. I am extremely nervous about Saturday.Do you know what it is about the H.E. Bailey Turnpike. Why do severe outbreaks so many times happen with supercells going up in SW OK, going up the turnpike into the OKC area impacting Moore?

Well, Moderate risks and High risks forecast can end up busting so I think its silly you assume the worst will happen just because they couldn't predict two storms occurring over one geographic spot last night. There could be too many storms Saturday that fight each for energy, morning/early afternoon storms, etc.

Saturday will get here soon enough. We need to pay attention to today and tomorrow first. (There is a hint of a moderate risk upgrade for tomorrow by the SPC).

[NikonNurse]

Yesterday morning, the meteorologists were predicting isolated severe weather centered on western Oklahoma. What ended up happening was a major outbreak centered on OKC. It's hard to believe it was a slight risk day and OKC wasn't even included in that risk yesterday morning. I am extremely nervous about Saturday.

Do you know what it is about the H.E. Bailey Turnpike. Why do severe outbreaks so many times happen with supercells going up in SW OK, going up the turnpike into the OKC area impacting Moore?

Tornadoes don't like the price of traveling on that toll way, so they are being vindictive..........

[bchris02]

Does tonight look like a repeat, with supercells going up in SW OK and moving up the H.E. Bailey into OKC?

[Dessert Fox]

Does tonight look like a repeat, with supercells going up in SW OK and moving up the H.E. Bailey into OKC?

No, It'll be storms moving in a line from the Texas panhandle through Oklahoma. It should just be mainly heavy rain and some hail/wind.

[gopokes88]

Sirens don't really bother me that much. They may be annoying but they force people to keep paying attention at a time they should be paying attention. We had a tornado heading NW last night, that's insane.

[LakeEffect]

Sirens don't really bother me that much. They may be annoying but they force people to keep paying attention at a time they should be paying attention. We had a tornado heading NW last night, that's insane.

Agree. Tornadoes can turn and form w/out notice, so warning a large area is prudent, despite the fact that it may warn people in an area out of danger. We were safe in downtown, but when the one popped up at S 44th & I-35, and KOCO said it might suddenly have turned N/NW, we were taken aback and headed into the basement for a bit.

[bchris02]

Agree. Tornadoes can turn and form w/out notice, so warning a large area is prudent, despite the fact that it may warn people in an area out of danger. We were safe in downtown, but when the one popped up at S 44th & I-35, and KOCO said it might suddenly have turned N/NW, we were taken aback and headed into the basement for a bit.

Did downtown get flooded like on May 31st?

[LakeEffect]

Did downtown get flooded like on May 31st?

The City noted quite a few downtown/urban core buildings that had minor flood damage. I saw some incredible photos of basements and streets filled w/ running water. And our basement had more water intrusion (nothing bad) than we had on May 31st, 2013. My anecdotal answer would be yes, it did, if not worse.

[Bobby821]

Hey Venture is there a problem with the chat room on Weather Spotlight? I get page can not be displayed where the chat should be and nothing on my system has changed or been blocked. The twitter feeds on the left show up fine just no chat.

[venture]

Hey Venture is there a problem with the chat room on Weather Spotlight? I get page can not be displayed where the chat should be and nothing on my system has changed or been blocked. The twitter feeds on the left show up fine just no chat.

None that I am aware of. There are several of us in there right now chatting with no issue. Only changes I made this morning were to the streaming source (youtube instead of ustream).

[Bobby821]

None that I am aware of. There are several of us in there right now chatting with no issue. Only changes I made this morning were to the streaming source (youtube instead of ustream).

Dang, I wonder how I can fix it then

[LocoAko]

One fatality now being reported as someone drowned in their storm shelter.

[bandnerd]

How is the Oklahoma River? I'm supposed to have a picnic at Wiley Post Park with my band and orchestra students tomorrow evening but if there is a chance of flooding that way I'll likely cancel. It would be nice to give them a heads up since they're all bringing food.

[venture]

[SoonerBeerMan]

The tracks of those tornadoes are unreal. Wobbling all over the place.

[RadicalModerate]

What is the logic behind randomly turning the tornado sirens on and off in the northernmost part of the county when the actual threat of a tornado is in the southernmost part of the county (and tracking away from the unaffected area)? Is it to "save lives"? Or is it to encourage "the boy who cried wolf" syndrome? (excuse me: "the boy who cried tiger" syndrome). Somehow, on an intuitive level, it doesn't make sense to alarm people without good reason.

[venture]

Woah, you actually replied to that?!? I thought, "Nah, Venture will just let that pass. No need to comment on something that absurd." I think you actually enjoy it.

Why wasn't the tiger outbreak in Tuttle included in SPC's forecast for the day????

I know I know...but I figured - get it out of my system now before Saturday and the total meltdown takes place.

What is the logic behind randomly turning the tornado sirens on and off in the northernmost part of the county when the actual threat of a tornado is in the southernmost part of the county (and tracking away from the unaffected area)? Is it to "save lives"? Or is it to encourage "the boy who cried wolf" syndrome? (excuse me: "the boy who cried tiger" syndrome). Somehow, on an intuitive level, it doesn't make sense to alarm people without good reason.

Might not be a bad idea for us to get another thread going on the OKC / OK County siren policy to give it some attention.

[Jim Kyle]

Might not be a bad idea for us to get another thread going on the OKC / OK County siren policy to give it some attention.

Great idea! As it happens I've been a weather buff longer than most of the crew here have been alive, and a distant cousin of mine (Tom Kyle, who passed away just this past year) issued the first ever broadcast Tornado warning back when he headed the Weather Bureau office at the old Will Rogers Field site. I'll definitely head for cover when the threat gets within a mile of me (and track what's happening both here, and via smartphone apps to see real-time radar), but last night was ridiculous.

And I'm more than a bit concerned about Saturday, but yesterday certainly shows how little we actually know about the factors that control the storms. Too much reliance on the models is, I think, even worse than too little!

[venture]

MESOSCALE DISCUSSION 0532
NWS STORM PREDICTION CENTER NORMAN OK
1020 AM CDT THU MAY 07 2015

AREAS AFFECTED...TX PANHANDLE...NWRN TX AND SWRN OK

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 071520Z - 071715Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...THREAT FOR MAINLY LARGE HAIL AND POSSIBLY STRONG WIND
GUSTS WILL PERSIST NEXT COUPLE HOURS FROM A PORTION OF THE TX
PANHANDLE INTO NWRN TX. THOUGH A WW IS POSSIBLE...THREAT FROM THESE
INITIAL STORMS MAY NOT BE SUFFICIENT FOR A WW ISSUANCE AT THIS TIME.
HOWEVER...THE SEVERE THREAT IS EXPECTED TO INCREASE BY EARLY
AFTERNOON FROM NWRN TX INTO SWRN OK...A WHICH TIME A WW MIGHT BE
NEEDED.

DISCUSSION...EARLY THIS MORNING A CONVECTIVE OUTFLOW BOUNDARY
EXTENDS ACROSS NRN TX INTO NWRN TX. SOUTH OF THIS BOUNDARY THE NEAR
SFC LAYER IS VERY MOIST WITH UPPER 60S DEWPOINTS OVER CNTRL TX AND
MID 60S OVER WRN TX GENERALLY SOUTH OF LUBBOCK. STORMS THAT ARE
CURRENTLY DEVELOPING OVER WRN TX APPEAR TO BE IN RESPONSE TO ZONE OF
ASCENT ACCOMPANYING A LOW AMPLITUDE SHORTWAVE TROUGH EVIDENT ON WV
IMAGERY. THESE STORMS APPEAR POORLY ORGANIZED AND ELEVATED ABOVE A
STABLE SFC LAYER...BUT EFFECTIVE BULK SHEAR FROM 30-40 KT IS
SUFFICIENT FOR SOME OF THE STORMS TO ACQUIRE MID-LEVEL UPDRAFT
ROTATION. STEEP MID-LEVEL LAPSE RATES...MODERATE INSTABILITY AND
POTENTIAL FOR UPDRAFT ROTATION WILL SUPPORT THREAT FOR LARGE HAIL
WITH SOME OF THIS INITIAL ACTIVITY.

WITH TIME THE OUTFLOW BOUNDARY WILL WEAKEN...AND RICHER MOISTURE
WILL ADVECT INTO NWRN TX AND SWRN OK WHICH /IN ADDITION TO DIABATIC
HEATING/ WILL SUPPORT DESTABILIZATION. IT IS POSSIBLE THAT SOME OF
THE SRN MOST STORMS OVER WRN TX MIGHT PERSIST AND INTENSIFY LATER
THIS MORNING INTO THE AFTERNOON AS THE BOUNDARY LAYER RECOVERS.
STORMS THAT PERSIST AND REDEVELOP THIS AFTERNOON IN VICINITY OF THIS
BOUNDARY WILL PROMOTE A GREATER SEVERE THREAT INCLUDING SUPERCELLS
CAPABLE OF VERY LARGE HAIL...DAMAGING WIND AND A FEW TORNADOES.

..DIAL/HART.. 05/07/2015

[Anonymous.]

Looks like generic linear storms and rain evolving out of NW TX. Main threat will be flooding.


EDIT:

southern cluster looks to be isolating more and is rotating slightly. Altus area will need to be aware.

[John1744]

Also I know we've bashed them plenty in the last few weeks but I'd like to applaud the NWS yesterday. They seemed very very on point with their warnings and general info. All the warnings were coming out at a rapid pace in a timely manner and gave people plenty of time to seek shelter if the need warranted it.

[SoonerBeerMan]

Also I know we've bashed them plenty in the last few weeks but I'd like to applaud the NWS yesterday. They seemed very very on point with their warnings and general info. All the warnings were coming out at a rapid pace in a timely manner and gave people plenty of time to seek shelter if the need warranted it.

Very good point!