June 4-7: Severe wx (Omaha tornado update)

[HarlequinBoy]

HIGH risk!! Mostly because of a wind threat and some tornado risk.

60% wind!! But a 15% tornado so maybe not a massive tornado outbreak...

[Weatherfreak14]

Code: Select all

SPC AC 051259
   
   DAY 1 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   0759 AM CDT THU JUN 05 2008
   
   VALID 051300Z - 061200Z
   
   ...THERE IS A HIGH RISK OF SVR TSTMS FROM SE SD AND SRN MN SW
   THROUGH CNTRL/ERN NEB AND WRN IA INTO CNTRL/ERN KS AND NW MO...
   
   ...THERE IS A MDT RISK OF SVR TSTMS SURROUNDING THE HIGH RISK
   AREA...FROM ERN SD/CNTRL MN AND WRN WI SSW INTO CNTRL OK...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE ABOVE AREAS
   FROM THE GRT LKS REGION SW INTO NWRN TX...
   
   ...SIGNIFICANT SEVERE WEATHER EVENT POSSIBLE ACROSS PARTS OF THE
   PLAINS AND THE MID/UPR MS VLY...
   
   ...SYNOPSIS...
   UNSEASONABLY STRONG UPR LOW NOW OVER THE FOUR CORNERS EXPECTED TO
   EJECT RAPIDLY NE INTO ND BY 12Z FRIDAY...PROPELLED BY FAST WLY JET
   OVER THE NE PACIFIC.  80-90 KT MID-LVL FLOW NOW ROUNDING BASE OF LOW
   WILL REDEVELOP NE ACROSS THE PLNS TODAY AND THE MID/UPR MS VLY
   TONIGHT.  AT THE SFC...ELONGATED LOW NOW IN WRN KS SHOULD DEEPEN
   SLIGHTLY AS IT LIFTS N TO THE NEB/SD BORDER THIS EVENING AND INTO SE
   ND EARLY FRIDAY.
   
   ...PLNS INTO MID/UPR MS VLY...
   SETUP DESCRIBED ABOVE YIELDS A WIDE CORRIDOR OF STRONG TO INTENSE
   VERTICAL SHEAR THAT WILL IN PART OVERLAY BROAD/MOIST WARM SECTOR
   FROM THE PLNS INTO THE MID/UPR MS VLY.  IN SHORT...SYNOPTIC PATTERN
   IS ONE OF EARLY SPRING KINEMATICS WITH LATE SPRING THERMODYNAMICS.
   A SIGNIFICANT SVR WEATHER OUTBREAK IN TERMS OF BOTH COVERAGE AND
   INTENSITY APPEARS LIKELY...ESPECIALLY OVER THE MDT RISK
   REGION...WHERE BOTH TORNADOES AND WIDESPREAD DMGG WINDS APPEAR
   LIKELY.
   
   TSTMS HAVE ALREADY FORMED OVER ERN CO...NW KS...AND SW NEB...AS
   ASCENT IMMEDIATELY DOWNSTREAM FROM UPR LOW ACTS ON MOIST PLUME
   WRAPPING WWD N OF KS SFC LOW.  THESE STORMS SHOULD PERSIST INTO THE
   AFTN...WITH ADDITIONAL DEVELOPMENT EXPECTED NEWD INTO CNTRL/NRN NEB.
    ALTHOUGH PRIMARY SVR THREAT EARLY ON SHOULD BE HAIL...A BIT LATER
   THIS MORNING A THREAT FOR TORNADOES WILL ALSO DEVELOP...MAINLY IN NW
   KS AND SW/S CNTRL NEB AS HEATING AND INCREASING UVV/MOISTURE
   AVAILABILITY ALLOW STORMS TO FORM IN AREA OF DEEPLY VEERING WIND
   PROFILES NE OF SFC LOW.
   
   FARTHER S AND E...MAJOR QUESTIONS REMAIN REGARDING THE PREDOMINANT
   STORM MODE AND CORRESPONDING SVR WEATHER THREATS FROM OK/KS NEWD
   INTO SD/MN.  WITH THE SERN U.S. RIDGE HOLDING FIRM...AND WITH
   UPSTREAM SPEED MAX ON ITS IMMEDIATE HEELS...EXPECT THAT HEIGHT FALLS
   ASSOCIATED WITH EJECTING FOUR CORNERS LOW WILL AT BEST ONLY GLANCE
   ERN PORTIONS OF THE SRN PLNS /I.E. S AND E OF I-44 IN OK/.  COUPLED
   WITH EXISTING VERY WARM 700 MB LAYER WITH THE RIDGE...EXPECT THAT
   THERE WILL BE A SHARP SERN EDGE TO THE SVR THREAT.
   
   CONSIDERING EXPECTED CONFIGURATION/MOVEMENT OF CAP AND HEIGHT FALL
   PATTERNS...EXPECT THAT MAIN SVR THREAT WILL BEGIN IN EARNEST LATER
   THIS MORNING IN NEB/NW KS.  A BIT LATER IN THE AFTN EXPECT THAT
   STORMS WILL DEVELOP SWD ALONG DRYLINE THROUGH KS INTO OK.  AT THE
   SAME TIME...INCREASING UVV/SUSTAINED MOISTURE INFLOW AND MODEST SFC
   HEATING MAY INITIATE SCTD STORMS ALONG OR N WARM FRONT FROM NRN NEB
   ACROSS ERN SD INTO MN/WI.  A FEW STORMS MAY ALSO FORM ALONG THE WARM
   FRONT IN MI.
   
   INTENSITY OF WIND FIELD THROUGHOUT THE PLNS ENSURES THAT ANY
   SUSTAINED UPDRAFTS WILL ROTATE.  BUT DECIDEDLY MERIDIONAL/LARGELY
   UNIDIRECTIONAL NATURE OF THE PROFILES ABOVE THE NEAR-SFC LAYER
   /REFLECTING EARLY-SPRING TYPE KINEMATIC SETUP/ LIKELY WILL YIELD
   VERY STRONGLY ELONGATED AND SHEARED STORMS.  NEVERTHELESS...GIVEN
   QUALITY OF MOISTURE INFLOW AND MERIDIONAL EXTENT OF WARM
   SECTOR...THESE COULD YIELD STRONG...LONG TRACK TORNADOES.
   
   ON THE OTHER HAND...POTENTIAL FOR STRONG DOWNDRAFT DEVELOPMENT WILL
   BE GREAT...ESPECIALLY OVER THE SRN HALF OF THE PLNS /AVERAGE LATE
   AFTN DCAPE EXPECTED TO BE AOA 1000 J PER KG IN KS AND OK/.  COUPLED
   WITH DEEP UNIDIRECTIONAL WIND FIELD...AND LINEAR DEEP FORCING FOR
   ASCENT /HEIGHT FALLS/...EXPECT THAT BY EVENING STORMS WILL HAVE
   ORGANIZED INTO AN EXTENSIVE BROKEN BAND FROM SRN/ERN NEB SWD INTO
   OK.  ESPECIALLY IN NEB...KS...WRN IA AND NW MO...INTENSE
   FORWARD-PROPAGATING SEGMENTS/LEWPS COULD PRODUCE LONG SWATHS OF DMGG
   WIND...IN ADDITION TO A FEW STRONG TORNADOES.
   
   
   ...UPR OH VLY/NY/NRN PA...
   SUSTAINED WAA AND BOUNDARY LAYER MOISTENING SHOULD SUPPORT THE
   DEVELOPMENT OF SCTD PERIODIC STORM CLUSTERS INVOF DIFFUSE WARM FRONT
   FROM PARTS OF ONTARIO E AND SE INTO UPSTATE NY/PA.  ALTHOUGH LARGE
   SCALE HEIGHT RISES WILL OCCUR ACROSS REGION ON NRN FRINGE OF SERN
   STATES RIDGE...DAYTIME HEATING ALONG WITH TERRAIN INFLUENCES MAYS
   SUFFICIENTLY BOOST INSTABILITY/UPLIFT TO POSE A RISK FOR A FEW
   STRONG/SVR TSTMS WITH HAIL AND/OR LOCALLY DMGG WINDS.
   
   ..CORFIDI/CROSBIE.. 06/05/2008
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
   CURRENT UTC TIME: 1310Z (9:10AM), RELOAD THIS PAGE TO UPDATE THE TIME

[wx247]

Well, as we have seen the last couple of days... we don't need a tornado to do quite a bit of damage. Those 80-100 mph winds of the last few days are quite enough. Tornado threat, I agree, is much more conditional.

I am extremely concerned about people who aren't experienced chasers out there today trying to bag their first twister. These storms, especially from I-70 northward, will be screaming to the northeast and it will be hard to keep up and away from them. Let's hope everyone stays safe today.

[Melissa]

Last time it looked like this, 22 died
BY STAN FINGER
The Wichita Eagle

Thursday could bring a tornado outbreak to the Great Plains, according to local meteorologists who are warning residents to pay attention to the weather.

Computer forecasting models for the day bear striking similarities to the conditions present on June 8, 1974, when 39 tornadoes touched down in the southern Plains and killed 22 people -- including six in Emporia.

"I think this event warrants more advance warning," said Robb Lawson, a meteorologist with the National Weather Service in Wichita.

The National Oceanic and Atmospheric Administration's Storm Prediction Center has been warning for days of an outbreak on Thursday.

Forecasters disagree on where the highest risk for tornadoes will be. Many say Iowa and Minnesota, said Mike Smith, chief executive officer of WeatherData Inc., a subsidiary of AccuWeather.

But Smith has his eyes on a corridor stretching from northern Oklahoma to central Iowa -- Enid to Des Moines. That includes Wichita and the surrounding area.

"Certainly Wichita, Topeka, Emporia, Salina, Chanute... essentially the eastern half of Kansas should really be paying attention on Thursday," Smith said.

Temperature and humidity patterns for Thursday are similar to the 1974 outbreak, he said, and a wave of energy in the upper atmosphere is projected to be in exactly the same position as on June 8, 1974.

The 1974 Emporia tornado touched down at about 6 p.m., grew to about a half-mile wide, and struck the city's northwest side, according to weather service archives.

It injured 200 people and caused an estimated $25 million in damage in Lyon County alone, striking a shopping center, mobile home park, nursing home, an apartment complex and residential neighborhoods in Emporia and about 10 farmsteads in the surrounding countryside.

The tornado was rated an F-4 and had a 38-mile track through Lyon, Osage and Shawnee counties.

With so much humidity in place, storms this Thursday could form and quickly become strong, forecasters say.

And with wind speeds in the upper atmosphere resembling early spring patterns, any tornadoes that touch down could move at more than 50 mph.

"If you take April dynamics and June thermodynamics," Smith said, "you have a potentially disastrous combination."
Reach Stan Finger at 316-268-6437 or sfinger@wichitaeagle.com.

http://www.kansas.com/news/local/v-prin ... 24100.html

[HarlequinBoy]

Well, as we have seen the last couple of days... we don't need a tornado to do quite a bit of damage. Those 80-100 mph winds of the last few days are quite enough. Tornado threat, I agree, is much more conditional.

I am extremely concerned about people who aren't experienced chasers out there today trying to bag their first twister. These storms, especially from I-70 northward, will be screaming to the northeast and it will be hard to keep up and away from them. Let's hope everyone stays safe today.

I definitely agree with you about the winds. My county has had severe damage this year from winds approaching 100 mph, while avoiding tornado damage from surrounding areas.

And yeah, I don't think today is a good chasing day. These don't seem to be your typical slow moving, LP Plains supercell.. but more linear HP storms.

[CrazyC83]

I agree the exact threat is uncertain, but whether we get strong/violent tornadoes or long track derecho winds, the damage will be great.

[CrazyC83]

Well, as we have seen the last couple of days... we don't need a tornado to do quite a bit of damage. Those 80-100 mph winds of the last few days are quite enough. Tornado threat, I agree, is much more conditional.

I am extremely concerned about people who aren't experienced chasers out there today trying to bag their first twister. These storms, especially from I-70 northward, will be screaming to the northeast and it will be hard to keep up and away from them. Let's hope everyone stays safe today.

I definitely agree with you about the winds. My county has had severe damage this year from winds approaching 100 mph, while avoiding tornado damage from surrounding areas.

And yeah, I don't think today is a good chasing day. These don't seem to be your typical slow moving, LP Plains supercell.. but more linear HP storms.

That combination sounds like a repeat of Super Tuesday transposed over the Midwest and Plains...

[Weatherfreak14]

Today is going to be a busy day...... Every please stay safe.... I really thing we will see some big tornados today and super bow-echoes from NE and northward.

[CrazyC83]

Already baseball size hail in western Nebraska.

[btangy]

A lot will be determined by how quickly everything congeals in to one nasty squall line after 00Z as alluded to in the SPC discussion. I think the high res models (NMM/ARW) are a bit slow clearing out the ongoing convection in Iowa so they are probably a bit delayed firing off convection later in the day in their progs. I think we'll get supercells beginning to develop around 18-20Z in C KS and NE and a bit later in E IA, but a squall line will become the dominate mode by 00Z with a few discrete cells out ahead of the main line capable of strong tornadoes. May be a setup where half a dozen supercells really go wild and the main mode of damage will be wind from the extensive squall line/derecho that will persist well after dark. 500+ reports of wind damage alone wouldn't surprise me given the geographic extent of this outbreak.

[CrazyC83]

Cells trying to break the cap in NE Kansas

[CrazyC83]

MESOSCALE DISCUSSION 1222
NWS STORM PREDICTION CENTER NORMAN OK
0930 AM CDT THU JUN 05 2008

AREAS AFFECTED...PARTS OF NRN IL INTO SRN MI

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 051430Z - 051600Z

MAIN CONVECTIVE THREAT MAY DEVELOP SOUTH/EAST OF TORNADO WATCH 458
AND SEVERE THUNDERSTORM WATCH 460 BY MIDDAY. IT IS NOT ENTIRELY
CLEAR THAT A NEW WW WILL BE NEEDED...BUT TRENDS WILL BE MONITORED.

LATEST RUC GUIDANCE INDICATES THAT A 50-70 KT 500 MB JET STREAK WILL
NOSE ACROSS LAKE MICHIGAN INTO LOWER MICHIGAN BETWEEN NOW AND
17-18Z...INTO/THROUGH THE CREST OF AN AMPLIFYING MID-LEVEL RIDGE.
CLUSTER OF STORMS SUPPORTED BY ASSOCIATED FORCING FOR UPWARD
VERTICAL MOTION IS STILL STRONG/SEVERE...BUT EASTERLY SYSTEM
RELATIVE INFLOW...EMANATING FROM COOLER/DRIER AND MORE STABLE
ENVIRONMENT OVER THE LOWER GREAT LAKES...MAY ULTIMATELY CONTRIBUTE
TO WEAKENING TRENDS.

SOUTHERLY LOW-LEVEL FLOW ACROSS THE MIDDLE MISSISSIPPI VALLEY TOWARD
THE LOWER LAKE MICHIGAN AREA IS GENERALLY ONLY MODERATE IN
STRENGTH...BUT COULD CONTRIBUTE TO SUFFICIENT FORCING TO MAINTAIN
VIGOROUS CONVECTIVE DEVELOPMENT ALONG THE CONFLUENT ZONE TRAILING
FROM THE INITIAL CONVECTIVE CLUSTER. THIS IS EXPECTED TO BECOME
QUASI-STATIONARY ACROSS SOUTHERN LOWER MICHIGAN...PERHAPS INTO THE
CHICAGO METRO AREA...WHERE HIGH PRECIPITABLE WATER WILL SUPPORT THE
RISK FOR HEAVY RAINFALL IN POSSIBLE DEVELOPING TRAINING CELLS. WEAK
TO MODERATE INSTABILITY IN THE PRESENCE OF MODERATE TO STRONG DEEP
LAYER SHEAR MAY BE FAVORABLE FOR EMBEDDED SUPERCELLS...WITH A RISK
MAINLY FOR DAMAGING WIND GUSTS AND SOME HAIL.

..KERR.. 06/05/2008


ATTN...WFO...DTX...IWX...GRR...LOT...

41708868 42078816 42318725 42608664 42638609 42578502
42298416 41908393 41528435 41468528 41318691 41148795
40998840 41368899

[wx247]

Cells trying to break the cap in NE Kansas

Those cells are high based and are above the cap.

[wx247]

Norman, OK has an audio/graphic briefing at 9:30:

http://www.srh.noaa.gov/oun/briefing/ounbrief.php

[CrazyC83]

MESOSCALE DISCUSSION 1223
NWS STORM PREDICTION CENTER NORMAN OK
1011 AM CDT THU JUN 05 2008

AREAS AFFECTED...PARTS OF CNTRL/ERN SD...NE NEB...SW MN...NW IA

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 051511Z - 051645Z

WATCHES ARE LIKELY LATER TODAY...BUT TRENDS ARE BEING MONITORED FOR
AN INCREASING SEVERE THREAT OVER THE NEXT FEW HOURS...AND THE
POSSIBILITY OF A WW IN THE NEAR TERM.

AN INITIAL WEAKENING MID-LEVEL JET STREAK/IMPULSE EMANATING FROM THE
FOUR CORNERS TROUGH IS CONTRIBUTING TO INCREASING CONVECTIVE
DEVELOPMENT ACROSS THE NORTH CENTRAL PLAINS. ACTIVITY LIKELY IS
BASED IN A ZONE OF STRONGER LOWER/MID-TROPOSPHERIC WARM ADVECTION.
AND...THIS APPEARS LIKELY TO REMAIN THE CASE INTO THE 18-20Z TIME
FRAME...AS FORCING SPREADS NORTH NORTHEASTWARD ACROSS THE MID
MISSOURI VALLEY. BUT...MODERATE DESTABILIZATION AND STRONG CLOUD
BEARING LAYER SHEAR SHOULD BE SUFFICIENT FOR A FEW SUPERCELLS
CAPABLE OF PRODUCING LARGE HAIL. A WARMING/DEEPENING SUB CLOUD
BOUNDARY LAYER ENVIRONMENT COULD BECOMING INCREASINGLY SUPPORTIVE OF
LOCALIZED DAMAGING WIND GUSTS BY EARLY AFTERNOON.

..KERR.. 06/05/2008


ATTN...WFO...MPX...FSD...OAX...ABR...GID...LBF...UNR...

42510135 44140178 44980125 45479917 45579583 43309524
42449567 41619700 41500042

[denise9855]

I live in Topeka Kansas and the hype is very high and people are actually beginning to get quite worried at this point. We have been very luck for the past 40 or so years but a big one is inevitable here.

[Mightybri]

I'm in Wichita.

They've already started arguing who has the best coverage (Chanel 9 in OKC).

I saw Melissa posted Stan Ringers article from yesterday, here is the one today.

[b]Severe weather risk 'high' for Wichita area[/b]BY STAN FINGER
The Wichita Eagle

Wichita and most of the eastern half of Kansas have been elevated to a high risk for severe weather today by the National Oceanic and Atmospheric Administration's Storm Prediction Center.

Portions of Iowa, Minnesota, Nebraska and Missouri are also included in the massive zone, and most of the rest of Kansas is in a slight or moderate risk zone.

Forecasters warn that tornadoes could form later this morning in northwest Kansas, and the tornado threat will spread east as heating of the atmosphere intensifies. The supercell thunderstorms can be expected to yield "strong.... long-track tornadoes," the center's synopsis of conditions state.

The National Weather Service in Wichita predicts thunderstorms will form in central and south-central Kansas by mid- to late afternoon, with the potential for hail as large as baseballs, damaging winds of up to 80 miles an hour, and "a few strong to violent long-lived tornadoes later this evening," according to a statement issued early this morning.

While the tornado threat should diminish late tonight in the Wichita area, lines of strong thunderstorms could still pound the region with hail, strong winds and heavy rain.

Check Kansas.com often for updates.

The wind's been howling most of the night and the clouds look like they've been attempting something most of the day. Felt the cold front come through this morning (old motorcycle injury).

B

[CrazyC83]

PDS watch likely coming:

MESOSCALE DISCUSSION 1224
NWS STORM PREDICTION CENTER NORMAN OK
1035 AM CDT THU JUN 05 2008

AREAS AFFECTED...SRN/ERN NEB INTO SW IA...PARTS OF NW MO

CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY

VALID 051535Z - 051700Z

SEVERE THREAT SHOULD INCREASE BY EARLY AFTERNOON...AND A WATCH WILL
BE ISSUED SHORTLY.

WHILE INCREASING CONVECTIVE DEVELOPMENT IS EXPECTED THROUGH THE
MIDDAY HOURS FARTHER NORTH...INHIBITION BENEATH THE NOSE OF A WARM
ELEVATED MIXED LAYER WILL BE AN ISSUE IN CLOSER PROXIMITY TO THE
WARM FRONT. THE FRONT IS IN THE PROCESS OF LIFTING NORTHWARD OUT OF
KANSAS INTO THE MID MISSOURI VALLEY...EAST NORTHEAST OF A SEASONABLY
DEEP AND DEEPENING SURFACE LOW MIGRATING ACROSS NORTHWEST KANSAS
INTO SOUTHWEST NEBRASKA.

HIGHEST PROBABILITY FOR THE INITIATION OF BOUNDARY LAYER BASED
STORMS THROUGH 18-20Z MAY BE WHERE A 60 KT SOUTHERLY 850 MB JET
STREAK INTERSECTS FRONT...ACROSS SOUTHEAST NEBRASKA...WEST/
SOUTHWEST OF OMAHA. IN THE PRESENCE OF MODERATE INSTABILITY...WITH
MIXED LAYER CAPE INCREASING IN EXCESS OF 2000 J/KG...STRONG DEEP
LAYER SHEAR AND LARGE CLOCKWISE CURVED LOW-LEVEL
HODOGRAPHS...TORNADIC SUPERCELLS SEEM PROBABLE BENEATH BROADER SCALE
DIFLUENT UPPER FLOW REGIME. STRONG TORNADOES ARE POSSIBLE.

..KERR.. 06/05/2008


ATTN...WFO...DMX...EAX...OAX...TOP...GID...GLD...

40569994 40979922 41009782 41489686 41489532 39649444
39859631 39729856 39970006

[HarlequinBoy]

Huh, I didn't think the Plains really got that hyped. The only places prone to severe weather that I've notice really hype is a few Birmingham and Atlanta station, and a few in Texas.

[denise9855]

Normally our meteorologists here don't get all worked up over the weather as it is normal here but this system has them all on edge!!!!