Plains Tornado Outbreak 4/14-15

[brunota2003]

Seward, OK needs to take cover!

TORNADO WARNING
NATIONAL WEATHER SERVICE NORMAN OK
254 AM CDT SAT APR 14 2012

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* TORNADO WARNING FOR...
LOGAN COUNTY IN CENTRAL OKLAHOMA...

* UNTIL 330 AM CDT

* AT 250 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS
DANGEROUS STORM WAS LOCATED 4 MILES SOUTHWEST OF SEWARD
MOVING NORTHEAST AT 25 MPH.

* LOCATIONS IMPACTED INCLUDE...
GUTHRIE...CEDAR VALLEY...MERIDIAN...NAVINA AND SEWARD.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 149 AND 162.

TVS signature is sitting just to the SW of the dot for Seward...by maybe a 1/2 mile.

[Cyclenall]

The velocity was not showing much to indicate a tornado...but at the same time, with that hook, it would not surprise me if one did touch down.

I would be floored if not at least a weak tornado came from a hook echo looking that great. If the velocity was there to match, a violent tornado is on the table.

What's crazy is how fast these hooks are forming, one scan it appears its a shapeless blob, line of storms then the next its a well defined hook echo wrapped right up. Its done that twice already with the Piedmont one. The line of storms is forming notches along itself, is that a pseudo-squall-line trying to supercellularize?

More than 3 TOR warnings at once now, more than so far in the last 18 hours. You know its "the day".

[brunota2003]

It was 2 or 3 supercells in close proximity. I noticed the Piedmont cell and the other one to it's NE (the other now not tornado warned storm) were both doing that on radar...base and velocity. They would tighten up over a couple scans, the hook would form, then just as quickly the circulation would broaden and the hook would get swallowed into the storm...only to do it again 10 or 15 minutes later.

I sent Norman NWS a message on facebook asking about it earlier...the hook was clearly there, but the rotation was having a hard time sustaining itself...my guess is that the storms are too close together and are pulling in too much rain cooled air...so it would get going, only to take a big gulp of cool air and it can't keep the balance to keep it sustained. We might eventually see one of them dominate and "kill off" the others and finally really get going, or they might all just keep doing their thing or dissipate. Still no reply back from them yet, though they are busy, so.

Also ironic is that 5 minutes after I posted that to them ("What is preventing tornadoes from developing this morning? Noticed the storm right on Piedmont has a well defined hook echo, yet the supercell is having a difficult time maintaining rotation in the lower levels on SRV. Seems like it spins up quickly, then falls apart almost as fast. Is it pulling in too much rain cooled air to keep a good balance, because of the storms off to it's northwest/northeast?") they issued the tornado warning.......... No, I didn't wake them up and draw their attention to the storm...at least I hope not!

If/when I get an answer, I'll post it!

[brunota2003]

They dropped the TOR warning, put out a Severe warning now...we'll see how it goes.

And with that, I'm heading off to bed...night/morning/afternoon/whateverrrr y'all!

[Cyclenall]

Its weird how there are no severe warnings now but 1 TOR warning. The main supercell we're discussing is in line to maybe impact another location but one can tell its a big one within the cluster/line. Has a huge notch on it.

[Cyclenall]

There is another notch on the very end (south) of the "line" near Cimarron City OK that starting to look good. Storms are blowing up rapidly just to the north of the main cluster/line and they too could become supercells. Whether or not the stuff behind them will interfere is the question.

[WeatherGuesser]

When does the Public SWO come out?

[CrazyC83]

When does the Public SWO come out?

Around 7 am I believe.

[CrazyC83]

SPC AC 140543

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1243 AM CDT SAT APR 14 2012

VALID 141200Z - 151200Z

...THERE IS A HIGH RISK OF SVR TSTMS TODAY ACROSS MUCH OF CENTRAL
AND EASTERN NEBRASKA AND PARTS OF ADJACENT NORTH CENTRAL
KANSAS/WESTERN IA...

...THERE IS A HIGH RISK OF SVR TSTMS LATE THIS AFTERNOON AND EVENING
ACROSS PARTS OF SOUTH CENTRAL KANSAS INTO NORTH CENTRAL OKLAHOMA...

...THERE IS A MDT RISK OF SVR TSTMS SURROUNDING THE HIGH RISK AREA
ACROSS THE REMAINDER OF CENTRAL AND EASTERN NEBRASKA...WESTERN
IOWA...NORTHWEST MISSOURI...CENTRAL AND EASTERN KANSAS...AND PARTS
OF NORTHERN AND CENTRAL OKLAHOMA...

...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MODERATE RISK
AREA ACROSS A LARGE PORTION OF THE CENTRAL AND SOUTHERN PLAINS...

...SYNOPSIS...
MODELS ALL INDICATE THAT A STRONG MID/UPPER JET STREAK...NOW DIGGING
INTO THE BASE OF A LARGE-SCALE UPPER TROUGH OVER THE WESTERN
U.S...WILL CONTINUE EASTWARD ACROSS THE SOUTHERN PLATEAU
TODAY...BEFORE NOSING NORTHEASTWARD ACROSS THE SOUTHERN ROCKIES INTO
THE CENTRAL PLAINS BY LATE TONIGHT. THIS IS EXPECTED TO INCLUDE A
90-100+ KT 500 MB JET CORE...WHICH MAY BE PRECEDED BY ANOTHER
SIGNIFICANT SPEED MAXIMUM ACROSS THE SOUTHERN ROCKIES/ CENTRAL
PLAINS REGION DURING THE DAY. GUIDANCE SUGGESTS THAT ASSOCIATED
FORCING WILL CONTRIBUTE TO RAPID INTENSIFICATION OF A SURFACE
CYCLONE TO THE LEE OF THE CENTRAL ROCKIES...WITH A 1000 MB LOW
CENTER DEEPENING BELOW 990 MB ACROSS EASTERN COLORADO INTO SOUTHWEST
NEBRASKA BETWEEN 14/12Z AND 15/00Z. WITHIN ITS WARM SECTOR...A
SOUTHERLY LOW-LEVEL JET WILL STRENGTHEN ACROSS THE SOUTHERN INTO
CENTRAL PLAINS /50+ KT AT 850 MB BY LATE AFTERNOON...INCREASING UP
TO 70 KT DURING THE EVENING/. THIS WILL CONTRIBUTE TO THE
CONTINUING NORTHWARD ADVECTION OF INCREASINGLY RICH MOISTURE
RETURNING OFF THE WESTERN GULF OF MEXICO...BENEATH AT LEAST MODESTLY
STEEP LAPSE RATES. MIXED LAYER CAPE IS EXPECTED TO EXCEED 2000 J/KG
WITHIN A CORRIDOR ACROSS CENTRAL TEXAS THROUGH MUCH OF OKLAHOMA AND
CENTRAL/EASTERN KANSAS...INTO THE VICINITY OF A WARM FRONTAL ZONE
EXTENDING EAST OF THE LOW ACROSS NEBRASKA INTO THE MISSOURI VALLEY.

THIS ENVIRONMENT IS EXPECTED TO BE CONDUCIVE FOR A SIGNIFICANT
OUTBREAK OF SEVERE STORMS...THAT MAY IMPACT PORTIONS OF THE CENTRAL
AND SOUTHERN PLAINS THROUGH MUCH OF THE PERIOD. THIS MAY INCLUDE
SEVERAL TORNADIC SUPERCELLS...AND PERHAPS...BY TONIGHT... THE
EVOLUTION OF A SUBSTANTIAL SQUALL LINE.

...NEBRASKA...
NORTH AND EAST OF THE DRY LINE WRAPPING INTO THE DEEPENING SURFACE
CYCLONE...INTO THE VICINITY OF THE WARM FRONT...CONDITIONS APPEAR
LIKELY TO BECOME VERY CONDUCIVE TO THE FORMATION OF DISCRETE
TORNADIC SUPERCELLS...AS THE EXIT REGION OF THE CYCLONIC MID/UPPER
JET OVERSPREADS THE REGION. THIS COULD OCCUR AS EARLY AS
18-21Z...IF NOT BEFORE...ACROSS PARTS OF SOUTHWEST INTO CENTRAL
NEBRASKA...BEFORE DEVELOPING EASTWARD AND INCREASING IN COVERAGE
ACROSS CENTRAL INTO EASTERN NEBRASKA THROUGH THE REMAINDER OF THE
AFTERNOON. THIS IS WHERE LOW-LEVEL HODOGRAPHS ARE EXPECTED TO
BECOME LARGE AND CLOCKWISE CURVED...AND SUPPORTIVE OF LONG-LIVED
SUPERCELLS CAPABLE OF PRODUCING STRONG TORNADOES.

...KANSAS AND OKLAHOMA INTO NORTH CENTRAL/NORTHWEST TEXAS...
BARRING COMPLICATIONS FROM RESIDUAL EARLY DAY CONVECTIVE
DEVELOPMENT...THE WARM SECTOR ENVIRONMENT AHEAD OF THE DRY LINE
ACROSS MUCH OF CENTRAL/EASTERN KANSAS AND OKLAHOMA PROBABLY WILL
STILL BE CAPABLE OF SUPPORTING LONG-LIVED SUPERCELLS CAPABLE OF
PRODUCING STRONG TORNADOES. HOWEVER...CONCERN EXISTS THAT THE
POTENTIAL COVERAGE OF DISCRETE SUPERCELL STORMS MAY REMAIN SOMEWHAT
SPARSE...PRIOR TO SQUALL LINE EVOLUTION THIS EVENING AS A COLD FRONT
OVERTAKES THE DRY LINE AND SURGES EASTWARD ACROSS THE PLAINS. ONCE
THIS OCCURS...DAMAGING WIND AND LARGE HAIL MAY BECOME THE PRIMARY
SEVERE THREAT.

..KERR/LEITMAN.. 04/14/2012

CLICK TO GET WUUS01 PTSDY1 PRODUCT

NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z
CURRENT UTC TIME: 1126Z (7:26AM), RELOAD THIS PAGE TO UPDATE THE TIME

[CrazyC83]

ZCZC SPCPWOSPC ALL
WOUS40 KWNS 141023
KSZ000-NEZ000-OKZ000-141800-

PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0523 AM CDT SAT APR 14 2012

...AN OUTBREAK OF SEVERE THUNDERSTORMS AND TORNADOES IS EXPECTED
OVER PARTS OF THE CENTRAL PLAINS THIS AFTERNOON AND TONIGHT...

THE NWS STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING THE
DEVELOPMENT OF A FEW STRONG...LONG-TRACK TORNADOES OVER PARTS OF THE
CENTRAL PLAINS THIS AFTERNOON AND TONIGHT.

THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE

CENTRAL AND EASTERN KANSAS
CENTRAL AND EASTERN NEBRASKA
CENTRAL AND NORTH CENTRAL OKLAHOMA

ELSEWHERE...SEVERE STORMS ARE ALSO POSSIBLE FROM...NORTH TEXAS TO
IOWA AND SOUTHEAST SOUTH DAKOTA/SOUTHERN MINNESOTA.

A VERY MOIST AND UNSTABLE AIR MASS WILL SPREAD NORTHWARD FROM
OKLAHOMA TO KANSAS AND NEBRASKA TODAY...IN ADVANCE OF A STRONG
UPPER-LEVEL STORM SYSTEM AND STRENGTHENING SURFACE LOW PRESSURE
SYSTEM. AFTER SOME MORNING-EARLY AFTERNOON STORMS FROM NORTHEAST
OKLAHOMA TO EASTERN NEBRASKA...MORE INTENSE STORM DEVELOPMENT IS
EXPECTED NEAR THE SURFACE LOW IN CENTRAL NEBRASKA THIS
AFTERNOON...AND SOUTHWARD ALONG THE WEST EDGE OF THE MOIST/UNSTABLE
AIR MASS IN CENTRAL KANSAS AND WESTERN/CENTRAL OKLAHOMA. THE STORM
ENVIRONMENT APPEARS TO BE VERY FAVORABLE FOR SUPERCELL THUNDERSTORMS
CAPABLE OF PRODUCING VERY LARGE HAIL AND DAMAGING TORNADOES FOR LONG
PATHS FROM LATE AFTERNOON UNTIL AT LEAST MIDNIGHT. EVEN THOUGH THE
STORMS COULD REMAIN WIDELY SEPARATED...FAST-MOVING TORNADOES
CONTINUING AFTER DARK WILL HEIGHTEN THE RISK TO LIFE AND PROPERTY.
SOME OF THE LARGER CITIES THAT MAY BE IMPACTED INCLUDE OMAHA AND
LINCOLN NEBRASKA...TOPEKA AND WICHITA KANSAS...AS WELL AS OKLAHOMA
CITY AND TULSA OKLAHOMA.

STATE AND LOCAL EMERGENCY MANAGERS ARE MONITORING THIS POTENTIALLY
VERY DANGEROUS SITUATION. THOSE IN THE THREATENED AREA ARE URGED TO
REVIEW SEVERE WEATHER SAFETY RULES AND TO LISTEN TO
RADIO...TELEVISION...AND NOAA WEATHER RADIO FOR POSSIBLE
WATCHES...WARNINGS...AND STATEMENTS LATER TODAY.

..THOMPSON.. 04/14/2012

$$

[Infdidoll]

Man, my mother-in-law lives in Owasso...and that cell that has been actively forming hook echos is rapidly approaching them and almost looks like another hook echo could be forming. Keeping an eye on it in case I need to call and wake her up. That area doesn't look good.

[CrazyC83]

000
NOUS43 KGID 141000
PNSGID
KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-
141700-

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE HASTINGS NE
500 AM CDT SAT APR 14 2012

...OUTBREAK OF SEVERE WEATHER EXPECTED TODAY...

SEVERE THUNDERSTORMS ARE FORECAST ACROSS SOUTH CENTRAL NEBRASKA
AND NORTH CENTRAL KANSAS TODAY...WITH THE WORST OF THE SEVERE
WEATHER EXPECTED THIS AFTERNOON AND EVENING. HAIL TO THE SIZE OF
BASEBALLS...THUNDERSTORM WIND GUSTS TO AROUND 70 MPH...AND
TORNADOES WILL ALL BE POSSIBLE ACROSS THE AREA. IN ADDITION...SOME
OF THE TORNADOES THIS AFTERNOON AND EVENING WILL HAVE THE
CAPABILITY TO BECOME LARGE AND LONG LIVED...THUS MAKING THIS A
VERY DANGEROUS SITUATION.

NOW IS THE TIME TO PREPARE...HAVE A PLAN IN PLACE SHOULD SEVERE
WEATHER THREATEN YOUR AREA. ALSO...DO NOT HESITATE TO SEEK SHELTER
SHOULD THE NATIONAL WEATHER SERVICE ISSUE A SEVERE THUNDERSTORM
WARNING OR TORNADO WARNING FOR YOUR AREA. FINALLY...CONTINUE TO
MONITOR THE FORECAST THROUGHOUT THE DAY SO THAT YOU REMAIN UP TO
DATE ON IMPENDING SEVERE WEATHER.

AS A REMINDER...

A WATCH MEANS CONDITIONS ARE FAVORABLE FOR SEVERE WEATHER DEVELOPMENT
WITHIN IN THE WATCH AREA. THERE IS NO CAUSE FOR IMMEDIATE
CONCERN...AND YOU MAY GO ABOUT YOUR NORMAL BUSINESS. STAY INFORMED
OF THE WEATHER SITUATION. KNOW YOUR COUNTY...NEARBY CITIES...AND
LOCAL LANDMARKS WHETHER AT HOME OR IF YOU ARE ON THE ROAD. LISTEN
TO WEATHER RADIO OR LOCAL MEDIA FOR UPDATED WEATHER INFORMATION.

A WARNING MEANS A SEVERE THUNDERSTORM OR TORNADO HAS BEEN OBSERVED
OR IS INDICATED BY DOPPLER WEATHER RADAR. IF A WARNING IS ISSUED
FOR YOUR LOCATION...IMMEDIATELY PUT YOUR EMERGENCY SAFETY PLAN
INTO ACTION.

$$

BRYANT/ADO

[Texas Snowman]

Probably a little wishful thinking on my part - who needs an outbreak of strong, long-tracked tornadoes - but I keep hearing from various sources an idea that supercell coverage on the southern end of the high risk may be somewhat limited.

With the worked over atmosphere from last night's storms in portions of Oklahoma, can't help but wonder if there's any potential for a "bust" of sorts today - i.e. lots of storm chasers looking at radars that aren't lit up as expected.

[CrazyC83]

I'm guessing the northern area will pop first - likely in the afternoon sometime near the triple point. The southern area may take longer as the cap is stronger there, but the dynamics are even more spectacular.

For 13Z, I would fill in the High Risk and extend the threat northward.

[CrazyC83]

Probably a little wishful thinking on my part - who needs an outbreak of strong, long-tracked tornadoes - but I keep hearing from various sources an idea that supercell coverage on the southern end of the high risk may be somewhat limited.

With the worked over atmosphere from last night's storms in portions of Oklahoma, can't help but wonder if there's any potential for a "bust" of sorts today - i.e. lots of storm chasers looking at radars that aren't lit up as expected.

Southern area has some potential for busting indeed. However, it does appear that the atmosphere is clearing out with the storms well to the east now.

[CrazyC83]

[CrazyC83]

The southern area already has very high parameters. But the cap has rebuilt...it's all waiting there. Warm front hasn't reached the northern area yet - it looks to be progged over central Kansas. The dry line appears to be on the Colorado and New Mexico borders right now.

[Texas Snowman]

Yeah, that satellite shot doesn't seem to bode well for Oklahoma.

I'm particularly concerned for Oklahoma City. I have friends that live there. And given their history and what we saw yesterday in Norman, the OKC area is just a natural magnet of sorts for tornadoes on days like these.

[CrazyC83]

CAPE values of over 2,000 at 7 am is not something you want to see. The cap will guide the area today, that is for sure.

[RL3AO]

Will we see the dreaded 60% tornado risk?