Severe Weather Outlook - May 12 & 13th

[venture]

Yeah, they were doing construction around the SRH office in Fort Worth and that is what knocked the page out. It is all southern region offices that are down, why they wouldn't have another backup at a separate location is beyong me.

[rod4soonrs]

I hope they don't keep it this way, I like the older format.

[kmf563]

That burst of air that came through last night was crazy. I watched the trees look like they were exploding down the middle then being sucked up by a giant vacuum. Very bizarre behavior. And the pressure was crazy. It was so strong it made me sick to my stomach and popped my ears. My windows were breathing instead of rattling. Guess I should have rethought living right next to the turnpike! It always seems to gun for that area. Memorial and Western.
And showers by candle light are not a fun way to start the day!! I have been without power for 10 hours now, I wonder how long we will be without it. I look forward to going home after work and going through my fridge.

[Jesseda]

my boss, came to work upset, a tree fell on her car during the night!!! She lives around 17th and brower area. She said it was a large tree that took out two cars

[OKCisOK4me]

I was out and about my condo complex and was checking out all the transformers blowing last night & thought, man, I need to go and get my flashlight before our electricity goes out. As I'm walking toward my unit---KAPOW---pitch black! Came back on at 7AM.

[westsidesooner]

That burst of air that came through last night was crazy. I watched the trees look like they were exploding down the middle then being sucked up by a giant vacuum. Very bizarre behavior. And the pressure was crazy. It was so strong it made me sick to my stomach and popped my ears. My windows were breathing instead of rattling. .

Sorry to hear you lost power. Good excuse to eat the rest of the ice cream though. I'd bet your power is back by this evening. OG&E still shows about 4600 outages.

If I'm not mistaken the reason the wind seemed so odd last night is because instead of blowing purely south to north it was blowing almost straight down. I noticed the same thing. We live in a forrested area and you could hear huge gusts all throughout the neighborhood. Very sporadic and very strong. I noticed several times our trees did the same thing. It looked like they were being smashed from above. That and it kept gettin warmer. Its called a heat burst.....maybe V can explain how it happens.

Intersting meteogram from west OKC shows the temp rise, dew point drop, pressure fall quickly, and the wind from last night.

[venture]

Yeah Heat Bursts are more common into the summer, but are still pretty rare. To keep it pretty simplistic...updraft of the storm completely dies and the storm collapses. So everything that was pushed up into the storm, instead of being let out gradually through normal outflow, just comes rushing out all at once. As the air moves faster it heats up so you have this sudden gush of wind crashing down that is also a good 15-30 degrees warmer than the surrounding air temp.

There is a lot more that goes into it, otherwise every decaying storm would do the same thing, but that is the basic overview.

[venture]

No real major changes with the outlook area today so far.

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1112 AM CDT WED MAY 13 2009

VALID 131630Z - 141200Z

...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING OVER PARTS OF OK...SOUTHEAST KS...NORTHWEST AR...MUCH OF MO AND MUCH OF IL...

...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE CENTRAL/SOUTHERN PLAINS INTO THE MID MISSISSIPPI VALLEY......

...SYNOPSIS...
VIGOROUS TROUGH AND STRONG POLAR JET MAX MOVES EWD FROM NRN PLAINS TO UPPER GREAT LAKES LATER TONIGHT...WITH GREATEST CONVECTIVE POTENTIAL REMAINING ALONG THE SRN PERIPHERY OF THIS SYSTEM WHERE THE RESERVOIR OF MOIST/UNSTABLE AIR MASS RESIDES. COLD FRONT EXTENDS FROM THE DEEP LOW WRN ONTARIO SWWD THRU UPPER MS VALLEY...CENTRAL KS TO NRN TX PANHANDLE THIS AM.

VERY STRONG SWLY LOW LEVEL JET AOA 60KT FROM SRN PLAINS INTO LOWER MO VALLEY CHARACTERIZED BY A PRONOUNCED EML ATOP A VERY MOIST BUT RELATIVELY SHALLOW MOIST LAYER. STRONG ISENTROPIC ASCENT UNDERWAY ACROSS MID MS VALLEY WITH CURRENT ELEVATED THUNDERSTORMS EXPECTED TO CONTINUE AND LIKELY BECOME MORE INTENSE THRU THE AFTERNOON.

...SRN PLAINS...
STRONG CAP IN PLACE AHEAD OF SEWD ADVANCING COLD FRONT. BY LATER THIS AFTERNOON THE FRONT WILL BE A PRIMARY FOCUS OF RAPID DEVELOPMENT OF SEVERE THUNDERSTORMS SWRN MO/SERN KS INTO NRN OK WHERE A VERY TO EXTREMELY UNSTABLE AIR MASS WILL BE IN PLACE. AS SFC TEMPS ACROSS OK WARM TO AOA 90F WITH DEWPOINTS WELL INTO THE 60S...MLCAPES WILL CLIMB TO AS HIGH AS 4000 J/KG. ONCE THE COMBINATION OF FRONTAL FORCING AND HEATING IS SUFFICIENT TO WEAKEN CAP...SEVERE THUNDERSTORMS INCLUDING SUPERCELLS WILL DEVELOP RAPIDLY. WITH THE THREAT AREA LOCATED ON THE SRN FRINGE OF THE STRONG POLAR JET PASSING BY TO THE N...DEEP LAYER SHEAR WILL BE A LIMITING FACTOR FOR TORNADOS. HOWEVER GIVEN THE AMOUNT OF INSTABILITY AND LOCALLY ENHANCED LOW LEVEL SHEAR BY EVENING AFTER STORMS ARE UNDERWAY...AT LEAST AN ISOLATED TORNADO THREAT IS EXPECTED. HOWEVER VERY LARGE HAIL IS GOING TO BE A PRIMARY CONCERN ALONG WITH DAMAGING DOWNBURST WINDS WITH ANY SUPERCELL THAT DEVELOPS IN THIS ENVIRONMENT.

A LINEAR MCS WILL THEN DEVELOP SEWD ACROSS MUCH OF OK INTO NRN AR TONIGHT WITH A CONTINUED THREAT OF AT LEAST DAMAGING WINDS CONTINUING.

[venture]

Short term model guidance has initiation along the front around 7PM tonight now (or a bit before) developing and moving through the Metro through 10PM. Instabilities are forecast to be completely insane by later today, they are already indicated to be very unstable by SPC mesoanalysis. I wouldn't expect a lot of tornadoes at all today, wind patterns aren't there. However, monster hail is looking pretty likely and that may prove to be a lot worse in some cases.

[westsidesooner]

Our storm from last night turned into a compact little MCV in Missouri.....interesting on radar.

Monster hail sounds ominous. I was wondering about the wind possibilities tonight. I dont want to clean up my yard twice...Before I clean up my yard I was curious what you thought the storms would do wind wise. The forecast is for supercells north and west turning into a squall line then a MCC. I was thinking there might be a lot of bowing line segments during the transition period. Do you think the storms will be south of OKC before they turn into a MCC or derecho? I guess timing is everything tonight.

[venture]

[Bunty]

I would suggest for those who are so interested in watching Oklahoma weather to get their own weather station, set it up in the backyard and go on the Internet with it. In other words, have your own personal weather station web site. A local example of how this is done is at:

Oklahoma City Live Weather

Another Oklahoma example is at: Stillwater Weather

[Thunder]

The storm last night was fun! I had lights that kept flickering and a few blown around things out front and a wooden bird losing the tail (found it). This is a wooden Carnival bird with motion wings (hangin under a tree) bought at Family Dollars for a bux.

Weather Blog

A look at the blog, there's a pix showing a large portion of the state under Moderate Risk. Now, if you read the text on the map, it is saying Tornadoes, rather than Isolated Tornadoes. It seem that they are expecting serious tornado touchdowns count.



One thing I do notice is that we finally have a clear, sunny skies before the storms. It's been so rare to have a clear, sunny skies before every storms this year.

[Thunder]

Guess who's/what's back!

NWS Norman, Oklahoma - Enhanced Weather Page

[venture]

A look at the blog, there's a pix showing a large portion of the state under Moderate Risk. Now, if you read the text on the map, it is saying Tornadoes, rather than Isolated Tornadoes. It seem that they are expecting serious tornado touchdowns count.

Don't read into their tornado part...they are a news station and they thrive off ratings. Also their Moderate Risk is too big. chop off the western third of that unless the dryline can find a way to explode. Unfortunately, the thermonuclear cap overhead will keep things well in check. Until about I would say 50-75 miles west of I-35 when thing should start cranking and the evolution into an MCS begins. Other than that, the activity will be very isolated out there and only warrants a slight risk. Remember, the risk area is based off of number of reports...not how bad it is. We could have one storm out there will drop softball hall and spin a tornado, but that isn't wide spread so a slight risk covers that pretty well.

This is NOT an ideal tornado setup. The wind patterns are not what they need to be. Now, any storms that form along the boundaries out there or interact with any left over outflow from yesterday...could get enough spin to put one or two down. The instability is there to support it if a trigger can be found from something that is not typical of a classic tornado day.

[Thunder]

Yeah, I know that. It's interesting. I bet they all got their chasers team out in full force expecting funnels here and there.

[venture]

The educated chasers out there know what to expect today, a tornado fest is not one of them.

[Bunty]

Guess who's/what's back!

NWS Norman, Oklahoma - Enhanced Weather Page

GREAT! Surely it can be said that our taxpayer dollars are being spent quite well.

[Luke]

GREAT! Surely it can be said that our taxpayer dollars are being spent quite well.

It would be nice if we all got a big annual opt-in check-list if we want to participate in a government program. Of course if we say no, then we couldn't see the results of that agency's work. And heck, they could create ANOTHER agency to make sure I didn't look at NOAA's web page since I wouldn't help fund it!

I can see it now...

Circle one...

I want to pay for Medicare even though I wouldn't get the benefits of it: YES NO
I want to pay for the NOAA: YES NO
I want to pay for a study on drunk prostitutes in China: YES NO
I want to pay for the Feds to go after those lying !@#$%^ at Cheerios: YES NO
I want to pay for a study on the sex and alcohol habits of gay Argentinans: YES NO
I want to pay more for my sugar filled carbonated beverages: YES NO
I certainly want to pay for irresponsible people's credit card bill: YES NO

[Bunty]

Sounds great. Now get me totally on your side by naming a country where what you say is actually done and it has living conditions we would glady live under.

If only the private sector could show us how it could be done by, for instance, allowing us to check off only the cable channels we want to see.

But I don't mind and not about to gripe over my tax dollars going to monitor the weather and alert us to possible dangerous conditions developing.

[Luke]

If only the private sector could show us how it could be done by, for instance, allowing us to check off only the cable channels we want to see.

I said that's what I wanted in a thread the other day!

See, you're starting to think like a libertarian!

[westsidesooner]

New MD out for Oklahoma...




MESOSCALE DISCUSSION 0814
NWS STORM PREDICTION CENTER NORMAN OK
0321 PM CDT WED MAY 13 2009

AREAS AFFECTED...SRN/SERN KS AND NERN INTO CENTRAL/WRN OK

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 132021Z - 132145Z

THUNDERSTORM INITIATION IS POSSIBLE BY 21-23Z OVER PORTIONS OF
SRN/SERN KS AND NRN INTO CENTRAL/WRN OK. AREA IS BEING MONITORED FOR
A WW.

WATER VAPOR IMAGERY REVEALS A S/W TROUGH PROGRESSING ENE ACROSS THE
CENTRAL/NRN PLAINS...ACCOMPANIED BY A 70+ KT MID LEVEL JET SAMPLED
BY NLG PROFILER. MEANWHILE AT THE SURFACE...A COLD FRONT POSITIONED
FROM ROUGHLY STJ TO ICT TO GAG AT 19Z IS FORECAST TO CONTINUE
SAGGING SWD ACROSS SERN KS INTO NRN AND WRN OK THROUGH THE EVENING.
STRONG SLY SURFACE WINDS OVER MUCH OF OK VEER TO SWLY ALONG THE
FRONT...AND THEN NLY IN ITS WAKE...RESULTING IN STRONG LOW LEVEL
CONVERGENCE. TEMPERATURES AHEAD OF THE COLD FRONT HAVE WARMED INTO
THE MID 80S TO AROUND 90 DURING THE AFTERNOON...AND SURFACE
DEWPOINTS RESIDE IN THE MID TO UPPER 60S. MODIFIED 18Z OUN SOUNDING
FOR A TEMPERATURE OF 90 AND DEWPOINT IN THE UPPER 60S YIELDS OVER
3500 J/KG OF MLCAPE. HOWEVER...A WARM CAPPING INVERSION STILL
RESIDES NEAR 700 MB...EVIDENT BY STABLE CUMULUS FIELD IN VISIBLE
SATELLITE IMAGERY. SHORT TERM DETERMINISTIC AND ENSEMBLE FORECAST
GUIDANCE INDICATES THAT COMBINATION OF LARGE SCALE ASCENT WITH UPPER
WAVE PASSING TO THE NORTH ALONG WITH FRONTAL CONVERGENCE WILL
ERODE/LIFT THE CAPPING INVERSION BY 23Z...RESULTING IN INCREASING
PROBABILITY OF THUNDERSTORM INITIATION FROM SERN/SRN KS INTO NRN/WRN
OK.

CONVECTIVE MODE ALONG FRONTAL BOUNDARY FROM MO INTO SERN/SRN KS AND
NRN OK IS EXPECTED TO TRANSITION TOWARD LINEAR RATHER QUICKLY
THROUGH THE EVENING...WHILE THE POTENTIAL FOR SLIGHTLY MORE DISCRETE
ACTIVITY MAY EXIST OVER WRN OK. THE COMBINATION OF VERY STEEP MID
LEVEL LAPSE RATES/LARGE CAPE AND EFFECTIVE BULK SHEAR AROUND 30-40
KT INVOF THE FRONT MAY FAVOR SUPERCELL STORM STRUCTURES
INITIALLY...POSING A THREAT OF LARGE-VERY LARGE HAIL ALONG WITH
ISOLATED TORNADOES. HOWEVER...STRONG FRONTAL FORCING WILL FAVOR
STORM TYPE TRANSITION TOWARD BOWS AND LEWPS WITHIN A FEW HRS AFTER
INITIATION...RESULTING IN AN INCREASING THREAT FOR DAMAGING WIND
GUSTS.

[Karried]

Westsidesooner,

Laymans's terms please .....

Tornados - Yes or No ? Time?

Should I start the Gary England Drinking Game anytime soon? lol, thanks ...

[Jon27]

Should I start the Gary England Drinking Game anytime soon? lol, thanks ...

Good one!

[Karried]

lol.. I figure if I have to be petrified of getting sucked up into oblivion, I might as well be drunk throughout it all! I kid, I kid .... maybe.