April 26-May 1 Plains/MW/OV Severe Weather, SPC Risk Level: Day 1 Slight Risk Forecasts and OBS Options

[Burr@Work]

Better images and news story:

SOURCE http://www.tennessean.com/article/20120426...60023/1969/NEWS

[melissa from ill...]

Reed Timmer on Twitter: Reed Timmer ‏ @reedtimmerTVN
Tomorrow could be an outbreak of tornadoes across much of central/eastern KS, including Wichita to Topeka, KS...

[jdrenken]

Still a slight...



10% tornado in KS just south of I-70






Nicely detailed report for a slight...

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1236 AM CDT FRI APR 27 2012

VALID 271200Z - 281200Z

...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS CENTRAL PLAINS TO
MO...

...SYNOPSIS...
PROGRESSIVE UPPER-AIR PATTERN FCST THROUGH PERIOD...FEATURING TWO
PRINCIPAL SHORTWAVE TROUGHS NOW OVER WRN CONUS...
1. HIGH-AMPLITUDE TROUGH NOW EVIDENT IN MOISTURE CHANNEL IMAGERY
FROM NRN NV NWWD ACROSS COASTAL BC. EMBEDDED VORTICITY MAXIMA ARE
EXPECTED TO PHASE TOGETHER IN SUPPORT OF CLOSED 500-MB CYCLONE
DEVELOPMENT DURING AFTERNOON...OVER NRN ROCKIES. CYCLONE CENTER
SHOULD REACH SERN MT/NERN WY/WRN SD BORDER REGION BY END OF PERIOD.
MEANWHILE...
2. COMPACT SHORTWAVE TROUGH -- INITIALLY OVER NRN NM/ERN CO BORDER
-- SHOULD MOVE ENEWD ACROSS CENTRAL HIGH PLAINS...REACHING ERN
PORTIONS KS/NEB BORDER REGION BY 28/00Z. THIS FEATURE WILL
DEAMPLIFY SUBSTANTIALLY FROM ABOUT 27/21Z ONWARD...REACHING NRN/ERN
IA AS WEAK VORTICITY LOBE BY END OF PERIOD.

MEANWHILE...STG MID-UPPER LEVEL SHORTWAVE TROUGH -- NOW MOVING SEWD
ACROSS INTERIOR MID-ATLANTIC REGION -- IS EXPECTED TO PIVOT EWD OVER
NEW ENGLAND EARLY IN PERIOD. ASSOCIATED SFC CYCLOGENESIS WILL
AFFECT CANADIAN MARITIMES. TRAILING COLD FRONT WILL DECELERATE
THROUGH AFTERNOON THEN BECOME QUASISTATIONARY OVER CAROLINAS. WRN
LIMB OF BAROCLINIC ZONE WILL MOVE NWD ACROSS SRN PLAINS AND
AR...LOCATED OVER OZARKS AND ERN KS AND CONNECTING TO SFC LOW OVER
E-CENTRAL KS BY 28/00Z. OCCLUDED FRONT WILL EXTEND NWWD FROM LOW
ACROSS NEB/SD TO SFC CYCLONE OVER ERN MT...PRECEDING NRN-STREAM
PERTURBATION. COLD FRONT TRAILING KS LOW WILL EXTEND WSWWD TO NWRN
OK AND NRN TX PANHANDLE BY 28/00Z...WITH DRYLINE EXTENDING SWD TO
N-CENTRAL/NERN OK THEN SSWWD OVER CENTRAL TX. LOW SHOULD MOVE NEWD
ACROSS NRN MO AND WEAKEN OVERNIGHT...WITH COLD FRONT SWWD ACROSS
CENTRAL OK AND NW TX BY 28/12Z.

...CENTRAL PLAINS TO MO...
--- EARLY ---
SCATTERED TSTMS MAY BE ONGOING AT START OF PERIOD...IN PLUME FROM
NEB PANHANDLE AND NERN CO SSEWD ACROSS PORTIONS WRN KS. THIS WILL
REPRESENT NEWD SHIFT OF STG DEEP-LAYER ASCENT PLUME AND ACCOMPANYING
CONVECTIVE REGIME NOW COVERING MUCH OF ERN CO AND EXTENDING INTO WRN
OK PANHANDLE. SVR THREAT BY START OF PERIOD TIME WILL BE MRGL AT
BEST...GIVEN WEAK NEAR-SFC THETAE EXPECTED OVER SWRN NEB AND WRN KS.
ISOLATED HAIL/GUSTS NEAR SVR LEVELS CANNOT BE RULED OUT. THIS
ACTIVITY WILL MOVE NEWD OVER NEB AND WEAKEN BY MIDDAY.

--- AFTERNOON/EVENING ---
RELATIVELY COMPACT CORRIDOR OF SUPERCELL/TORNADO POTENTIAL MAY
DEVELOP AND SHIFT EWD TODAY ACROSS MAINLY KS. LARGE/DAMAGING HAIL
ALSO IS POSSIBLE. SOME UNCERTAINTIES REMAIN REGARDING
TIMING/DURATION OF FAVORABLE SFC HEATING/DESTABILIZATION OVER
PORTIONS CENTRAL-ERN KS...OTHERWISE NARROW CORRIDOR OF EVEN GREATER
SVR PROBABILITIES MAY BECOME APPARENT.

BY EARLY AFTERNOON...CORRIDOR OF FAVORABLE DESTABILIZATION IS
POSSIBLE BEHIND MORNING ACTIVITY AND AHEAD OF SURGING DRYLINE. MOST
PROBABLE LOCATION ATTM APPEARS TO BE ACROSS PORTIONS WRN/CENTRAL
KS...IN ARC FROM N THROUGH ESE OF NEARBY SFC LOW. MODIFIED
RUC/ETA-KF FCST SOUNDINGS SUGGEST MID-UPPER 60S F SFC
TEMPS...CERTAINLY ATTAINABLE WITH EVEN BRIEF SLOT OF PRE-DRYLINE SFC
INSOLATION...WILL BE SUFFICIENT TO YIELD SFC-BASED EFFECTIVE INFLOW
PARCELS AND MLCAPE 500-1500 J/KG. STG VEERING OF WINDS WITH HEIGHT
AND LOW-LEVEL SPEED SHEAR...COMBINED WITH LOW-LEVEL VORTICITY INVOF
SFC LOW AND NEARBY WARM FRONTAL ZONE...SUPPORT RISK FOR SUPERCELLS
WITH LARGE HAIL AND TORNADOES.

EWD-SHIFTING WARM SECTOR SLOT WILL WIDEN AND BECOME MORE BUOYANT
WITH TIME AND EWD EXTENT ACROSS KS DURING MID-LATE AFTERNOON. ARC
OF SVR TSTMS SHOULD DEVELOP....WHETHER SEPARATELY FROM EARLIER
ACTIVITY FARTHER W OR AS SEWD-BUILDING EXTENSION. ACTIVITY
EVENTUALLY MAY MERGE INTO SVR WIND-PRODUCING AND NEARLY CONTINUOUS
ARC. HOWEVER...FOR MUCH OF AFTERNOON INTO EARLY EVENING...PRESENCE
OF SIGNIFICANT ORTHOGONAL COMPONENT OF FLOW ALOFT SUGGESTS DISCRETE
SUPERCELLS WILL REMAIN OVER ERN KS INTO THAT PART OF SWRN MO ALONG
AND SW OF WARM FRONT. PRECONVECTIVE MLCAPE MAY REACH 2500 J/KG IN
E-CENTRAL/SERN KS...WITH 0-1 KM SRH 200-300 J/KG AND EFFECTIVE SHEAR
MAGNITUDES NEAR 50 KT.

EXTENSION OF THREAT INTO N-CENTRAL/NERN OK IS CONDITIONAL DUE TO
SUBSTANTIALLY STRENGTHENED CAPPING LIKELY OVER OK...ALONG WITH
WEAKER LOW-LEVEL CONVERGENCE. SVR PROBABILITIES THEREFORE DIMINISH
WITH SWD EXTENT OVER OK. SVR POTENTIAL SHOULD DIMINISH WITH EWD
EXTENT OVERNIGHT ACROSS S-CENTRAL MO TO MS RIVER AREA.

...SERN CONUS...
SCATTERED TSTMS ARE EXPECTED TO DEVELOP INVOF SFC FRONTAL
ZONE...FROM ERN SC AT LEAST AS FAR WNWWD AS NERN AL...BECOMING
WIDELY SCATTERED TO ISOLATED FARTHER NW WHERE LOW-LEVEL FRONTAL
FORCING WILL BE WEAK. SFC DEW POINTS 60S F...STG HEATING...AND
FRONTAL LIFT WILL BE SUFFICIENT TO REMOVE MLCINH AMIDST 1000-2000
J/KG MLCAPE. LOW-LEVEL FLOW AND SHEAR WILL BE WEAK...BENEATH
GENERALLY 25-35 KT EFFECTIVE SHEAR MAGNITUDE. PRIMARY MODE SHOULD
BE MULTICELLULAR...WITH SPORADIC STG-SVR DOWNDRAFTS AND HAIL
POSSIBLE. CONVECTIVE COVERAGE AND SVR POTENTIAL SHOULD DIMINISH
MARKEDLY AFTER 00Z...DUE TO STABILIZING EFFECTS OF BOTH SFC DIABATIC
COOLING AND CONVECTIVE OUTFLOWS.

..EDWARDS/GARNER.. 04/27/2012

[jdrenken]

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0100 AM CDT FRI APR 27 2012

VALID 281200Z - 291200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE OH
VALLEY...

...SYNOPSIS...

BLOCKY SYNOPTIC PATTERN WILL PREVAIL SATURDAY WITH UPPER RIDGE OVER
THE CNTRL CANADIAN PROVINCES INTO THE UPPER MS VALLEY FLANKED BY AN
UPPER LOW OVER THE NRN ROCKIES AND ERN CANADA. A SRN STREAM
SHORTWAVE TROUGH MOVING INTO THE SRN AND CNTRL HIGH PLAINS AS OF
EARLY FRIDAY MORNING WILL DEAMPLIFY AS IT EJECTS INTO MEAN RIDGE
POSITION THAT WILL BE IN PLACE OVER THE UPPER MS AND OH VALLEYS.

WARM FRONT WILL LIFT NWD TO NEAR THE OH RIVER...BUT NWD PROGRESS
WILL BE IMPEDED BY SFC HIGH PRESSURE CENTERED OVER ONTARIO. THE
EJECTING BUT DEAMPLIFYING WAVE WILL PROVIDE IMPETUS FOR A COLD FRONT
TO SWEEP SEWD. BY THE END OF THE PERIOD THIS BOUNDARY SHOULD EXTEND
FROM THE MID ATLANTIC REGION SWWD INTO NRN TX.

...OH VALLEY AREA...

ELEVATED SHOWERS AND THUNDERSTORMS SHOULD BE IN PROGRESS FROM THE
UPPER MS VALLEY INTO A PORTION OF THE OH VALLEY WITHIN ZONE OF
ISENTROPIC ASCENT NORTH OF WARM FRONT. ACTIVITY WILL SHIFT ENEWD
DURING THE DAY BUT LIKELY REINFORCE THE WARM FRONT AND SLOW ITS NWD
PROGRESS. ATMOSPHERE WILL DESTABILIZE SOUTH OF THIS FEATURE AS AXIS
OF LOW 60S DEWPOINTS ADVECT NEWD BENEATH PLUME OF STEEPER MID LEVEL
LAPSE RATES. LOW CLOUDS SHOULD BEGIN TO DISSIPATE IN WARM SECTOR BY
LATE MORNING OR AFTERNOON ALLOWING THE BOUNDARY LAYER TO DESTABILIZE
WITH MLCAPE TO 1500 J/KG. POTENTIAL WILL EXIST FOR A FEW STORMS TO
REDEVELOP ALONG CONVECTIVELY REINFORCED WARM FRONT...ESPECIALLY FROM
SERN IL...SRN IND INTO THE NRN HALF OF KY WHERE SHORTWAVE RIDGE WILL
BE SUPPRESSED BY THE EJECTING SHORTWAVE TROUGH. THIS REGION WILL
ALSO REMAIN ON NRN FRINGE OF EML WHERE THE CAP SHOULD BE SOMEWHAT
WEAKER THAN FARTHER SOUTH. OTHER STORMS MAY DEVELOP ALONG THE COLD
FRONT AS IT ADVANCES SEWD. SHOULD SFC BASED STORMS DEVELOP...WLY
UNIDIRECTIONAL SHEAR FROM 40-50 KT WILL SUPPORT ORGANIZATION
INCLUDING A FEW SUPERCELLS WITH DAMAGING WIND AND LARGE HAIL THE
MAIN THREATS.


...OK THROUGH THE TX PANHANDLE...

THUNDERSTORM POTENTIAL IS EXPECTED TO REMAIN LIMITED DURING THE DAY
ALONG STALLING FRONT FROM NRN TX INTO THE MID MS VALLEY REGION DUE
TO A CAPPING INVERSION AND WEAK FRONTAL CONVERGENCE.
HOWEVER...STRENGTHENING SLY NOCTURNAL LLJ WILL CONTRIBUTE TO NWD
DESTABILIZATION OVER THE SRN HIGH PLAINS FROM OK INTO THE TX
PANHANDLE. ELEVATED STORMS WILL LIKELY DEVELOP WITHIN THIS ZONE OF
ISENTROPIC ASCENT SATURDAY NIGHT. GIVEN STEEP LAPSE RATES AND
500-1000 J/KG MUCAPE...A FEW OF THE STORMS COULD PRODUCE ISOLATED
HAIL. AT THIS TIME IT APPEARS STORMS WILL PROBABLY REMAIN NORTH OF
THE STRONGER INSTABILITY WHICH MAY LIMIT OVERALL HAIL SIZE.
HOWEVER...THIS AREA MIGHT NEED TO BE INCLUDED IN A SLIGHT RISK IN
LATER OUTLOOKS.

..DIAL.. 04/27/2012

[jdrenken]

MESOSCALE DISCUSSION 0602
NWS STORM PREDICTION CENTER NORMAN OK
0616 AM CDT FRI APR 27 2012

AREAS AFFECTED...PARTS OF CNTRL-ERN KS AND FAR WRN MO

CONCERNING...OUTLOOK UPGRADE

VALID 271116Z - 271215Z

THERE WILL BE A CATEGORICAL UPGRADE FROM A SLIGHT TO MODERATE RISK
OVER CNTRL-ERN KS AND FAR WRN MO FOR THE UPCOMING 1300Z DAY 1
CONVECTIVE OUTLOOK. CONFIDENCE HAS INCREASED REGARDING A GREATER
THREAT FOR SUPERCELLS POTENTIALLY CAPABLE OF A FEW STRONG TORNADOES
AND LARGE DESTRUCTIVE HAIL ACROSS THE MODERATE RISK AREA.

..SMITH.. 04/27/2012

[Burr@Work]

More video including interviews from the tornado in Franklin, TN last night:

http://www.tennessean.com/videonetwork/1597300285001?odyssey=mod|tvideo2|article

[jdrenken]

PWO issued ladies and gentlemen...

PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0601 AM CDT FRI APR 27 2012

...SEVERE THUNDERSTORMS EXPECTED OVER PARTS OF CENTRAL AND EASTERN
KANSAS AND FAR WESTERN MISSOURI TODAY...

THE NWS STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING THE
DEVELOPMENT OF A FEW STRONG TORNADOES AND LARGE DESTRUCTIVE HAIL
OVER PARTS OF CENTRAL AND EASTERN KANSAS AND FAR WESTERN MISSOURI
TODAY.

THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE

CENTRAL AND EASTERN KANSAS
FAR WESTERN MISSOURI

ELSEWHERE...SEVERE STORMS ARE ALSO POSSIBLE SURROUNDING THE GREATEST
RISK AREA...FROM WEST CENTRAL PORTIONS OF KANSAS EASTWARD INTO
CENTRAL AND SOUTHWEST MISSOURI.

A POTENT UPPER LEVEL STORM SYSTEM IS FORECAST TO MOVE FROM
SOUTHEASTERN COLORADO THIS MORNING TO THE LOWER MISSOURI RIVER
VALLEY BY THIS EVENING. A WARM AND INCREASINGLY MOIST AND
DESTABILIZING LOW LEVEL AIRMASS WILL SPREAD NORTHWARD INTO THE AREA
TODAY AS A WARM FRONT MOVES FROM NORTHERN OKLAHOMA INTO KANSAS. AS
THIS OCCURS...WINDS ALOFT WILL STRENGTHEN AND BECOME MORE FAVORABLE
FOR AN EPISODE OF SEVERE THUNDERSTORMS ACROSS THE MODERATE RISK
AREA. THE THREAT FOR SEVERE THUNDERSTORMS WILL MOST LIKELY BEGIN AS
EARLY AS MIDDAY AND FEATURE A RISK FOR LARGE DESTRUCTIVE
HAIL...DAMAGING STRAIGHT-LINE WINDS...AND THE POSSIBILITY OF A FEW
STRONG TORNADOES. BY THIS EVENING...THE SEVERE RISK WILL SHIFT
EASTWARD INTO PORTIONS OF EASTERN KANSAS AND FAR WESTERN
MISSOURI...WITH AN ATTENDANT RISK FOR LARGE HAIL...DAMAGING
WINDS...AND A FEW STRONG TORNADOES.

STATE AND LOCAL EMERGENCY MANAGERS ARE MONITORING THIS DEVELOPING
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.

..SMITH.. 04/27/2012

[jdrenken]

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0710 AM CDT FRI APR 27 2012

VALID 271300Z - 281200Z

...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF CENTRAL/EASTERN KS
AND WEST CENTRAL MO...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CENTRAL
PLAINS...

...AN ACTIVE SEVERE WEATHER EVENT IS EXPECTED LATER THIS AFTERNOON
AND EVENING OVER PARTS OF THE CENTRAL PLAINS...

...CENTRAL PLAINS...
MORNING WATER VAPOR LOOPS SHOW A COMPACT UPPER SHORTWAVE TROUGH OVER
THE CENTRAL ROCKIES. THIS FEATURE WILL EJECT EASTWARD INTO THE
PLAINS TODAY. AN ASSOCIATED 70 KNOT MID LEVEL SPEED MAX WILL
OVERSPREAD PARTS OF OK/KS WHILE THE MAIN SURFACE LOW TRACKS ACROSS
KS. STRONG SOUTHERLY LOW LEVEL WINDS AHEAD OF THE LOW WILL HELP A
WARM FRONT LIFT NORTHWARD ACROSS EASTERN KS. THE END RESULT WILL BE
A FOCUSED AREA OF ENHANCED THREAT OF SEVERE THUNDERSTORMS AND
TORNADOES LATER THIS AFTERNOON AND EVENING.

SCATTERED THUNDERSTORMS ARE ONGOING THIS MORNING OVER WESTERN KS
AHEAD OF THE MAIN UPPER SYSTEM. PRESENT INDICATIONS ARE THAT THESE
STORMS MAY CONTINUE THROUGH THE MORNING AND INTENSIFY FURTHER BY
EARLY AFTERNOON OVER CENTRAL KS AS A COMBINATION OF DAYTIME HEATING
AND MOISTURE ADVECTION DESTABILIZE THE REGION. THE CLUSTER OF
STORMS IS EXPECTED TO TRACK EASTWARD ALONG/NORTH OF PRIMARY
INSTABILITY GRADIENT THROUGH THE DAY ACROSS CENTRAL/EASTERN KS AND
EVENTUALLY TOWARD THE KC AREA BY EARLY EVENING. BACKED LOW LEVEL
WINDS AND ENHANCED VERTICAL SHEAR NEAR THE WARM FRONT WILL PROMOTE
SUPERCELL STRUCTURES CAPABLE OF LARGE HAIL. STORMS MAY EVENTUALLY
BECOME SURFACE BASED BY LATE AFTERNOON WITH AN INCREASING RISK OF
TORNADOES /POSSIBLY STRONG/.

FARTHER SOUTH...MODEL SOLUTIONS ARE IN GOOD AGREEMENT THAT DISCRETE
CONVECTION WILL FORM ALONG THE DRYLINE OVER SOUTH CENTRAL KS BY LATE
AFTERNOON. THIS ACTIVITY WILL FORM IN A REGION OF STRONG
INSTABILITY AND FAVORABLE VERTICAL SHEAR FOR DISCRETE SUPERCELLS
CAPABLE OF VERY LARGE HAIL AND TORNADOES. THE WARM SECTOR WILL BE
RATHER NARROW...BUT WILL BE SHIFTING SLOWLY EASTWARD THROUGH THE
EVENING. IT CURRENTLY APPEARS THE MOST INTENSE STORMS WILL TRACK AS
FAR EAST AS WESTERN MO BEFORE A SLOW WEAKENING PROCESS THIS EVENING.


...SOUTHEAST STATES...
A WEAK SURFACE BOUNDARY WILL EXTEND FROM NORTHERN AL INTO SC LATER
TODAY. STRONG HEATING AND A MOIST AIR MASS WILL PROMOTE A RISK OF
SCATTERED THUNDERSTORMS ALONG THE BOUNDARY. VERTICAL SHEAR WILL BE
RELATIVELY WEAK. HOWEVER...A FEW OF THE STRONGER MULTICELL STORMS
MAY POSE A RISK OF LOCALLY GUSTY WINDS AND HAIL DURING THE LATE
AFTERNOON AND EVENING HOURS.

..HART/SMITH.. 04/27/2012

[helpdeskian]

Just ran across this on twitter.

@TWCMikeBettes: Just spoke with @drgregforbes. He's upping the TORCON to 8 in Southeast Kansas today. Be prepared!

twitter

[jdrenken]

Just ran across this on twitter.
twitter

Rightfully so...

MESOSCALE DISCUSSION 0603
NWS STORM PREDICTION CENTER NORMAN OK
1015 AM CDT FRI APR 27 2012

AREAS AFFECTED...CNTRL KS...FAR N-CNTRL OK

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

VALID 271515Z - 271715Z

SUPERCELLS SHOULD FORM ALONG EWD SURGING DRYLINE IN CNTRL KS TO
PERHAPS N-CNTRL OK BY EARLY AFTERNOON. STRONG LOW/DEEP-LAYER SHEAR
COMBINED WITH STEEP MID-LEVEL LAPSE RATES AMIDST MODERATELY LARGE
BUOYANCY WILL LIKELY YIELD PRIMARY INITIAL THREATS OF LARGE HAIL AND
TORNADOES. THE PROBABILITY OF A TORNADO WATCH ISSUANCE IS 95
PERCENT.

15Z SURFACE ANALYSIS PLACED A 996 MB CYCLONE AROUND 30 SE GLD WITH A
SLOWLY ADVANCING WARM FRONT ARCING SEWD TOWARDS THE OZARK PLATEAU
AND A SURGING DRYLINE EXTENDING SWD INTO WRN OK. SHOWERS AND TSTMS
HAVE BEEN PREVALENT NEAR THE TRIPLE POINT WITH ABUNDANT STRATUS IN
THE WARM/MOIST SECTOR OVER MUCH OF KS. HOWEVER...STRONGER HEATING IS
OCCURRING IN NRN OK WHERE TEMPERATURES HAVE WARMED INTO THE LOWER TO
MIDDLE 70S AND CLOUD BREAKS APPEAR TO BE OCCURRING IN A NARROW
CORRIDOR FROM COMANCHE TO PAWNEE COUNTIES IN SWRN KS. MODIFIED 12Z
DDC RAOB AND MODEL FORECAST SOUNDINGS SUGGEST THAT EVEN WITH MODEST
HEATING...THE STRENGTH OF THE FORCING WILL BE SUFFICIENT FOR MINIMAL
INHIBITION ALONG THE DRYLINE BY MIDDAY.

ALTHOUGH LOW-LEVEL SLYS HAVE COMMENCED WEAKENING WITH SRN EXTENT IN
THE WARM/MOIST SECTOR /PER TIME SERIES OF HAVILAND KS
PROFILER/...0-1 KM SHEAR SHOULD REMAIN AOA 15 KT WITH STRONGER
LOW-LEVEL SHEAR RELEGATED ALONG AND NE OF THE WARM FRONT. WITH
EFFECTIVE SHEAR OF 40-50 KT AND MLCAPE EXPECTED TO APPROACH 2500
J/KG IN S-CNTRL KS/N-CNTRL OK...THIS SETUP WILL BE FAVORABLE FOR
SUPERCELLS WITH THREATS OF LARGE HAIL AND TORNADOES PRIMARILY IN
CNTRL KS.

..GRAMS.. 04/27/2012

[jdrenken]

12Z NAM sounding for Joplin....

21z


HODO

[Burr@Work]

NWS confirms the damage at the ballpark in Franklin, TN last night was consistent with an EF0 tornado, EF0...WIND SPEEDS 65 TO 85 MPH. My family and the hundreds of others out for little league last night were very lucky.

http://www.srh.noaa.gov/productview.php?pil=OHXPNSOHX

For those in the warning areas today/tonight, be ready and stay safe! (I'm from the northeast and not accustomed to these suckers like ya'll are in the midwest and the south. Don't know what to tell you - you already know more than I do about how to prepare and what to do).

[WeatherMonger]

Extended a smidgeon SE into MO

[WeatherMonger]

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1113 AM CDT FRI APR 27 2012

VALID 271630Z - 281200Z

...THERE IS A MDT RISK OF SVR TSTMS OVER CENTRAL/ERN KS INTO WRN
MO...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CENTRAL PLAINS INTO
THE LOWER MO VALLEY...

...THERE IS A SLGT RISK OF SVR TSTMS FROM NERN GA INTO SC...

...KS/WRN MO AREA...
WATER VAPOR IMAGERY INDICATES AN INTENSE UPPER VORTICITY MAX OVER
EXTREME NWRN KS. THIS SYSTEM IS EXPECTED TO MOVE ENEWD AND THEN
NEWD OVER THE MO RIVER VALLEY AND WEAKEN TONIGHT AS THE PRIMARY
UPPER LOW OVER DEVELOPS OVER THE NRN ROCKIES...AND PROVIDE STRONG
DYNAMIC FORCING FOR ASCENT. AT THE SURFACE...A CO-LOCATED DEEP LOW
OVER EXTREME NWRN KS IS FORECAST TO MOVE EWD INTO CENTRAL KS THIS
AFTERNOON...CONTINUING TOWARD NWRN MO TONIGHT. A WARM FRONT
EXTENDING ESEWD FROM THE LOW WILL SLOWLY LIFT NWD AS EXTENSIVE
CLOUDS OVER CENTRAL/ERN KS WILL BE SLOW TO DIMINISH. A DRY LINE
ARCING SWD FROM THE LOW ACROSS WRN OK WILL SURGE EWD ACROSS SRN KS
AND OK THIS AFTERNOON IN RESPONSE TO INCREASING DEEP LAYER WESTERLY
FLOW ON THE SRN PERIPHERY OF THE UPPER SYSTEM.

A NARROW LINE OF CONVECTION IS CURRENTLY INDICATED BY VISIBLE
SATELLITE AND RADAR FROM NEAR HLC SWD TO EAST OF DDC...WITH BREAKS
IN CLOUD COVER NOTED IMMEDIATELY IN ADVANCE OF THE CONVECTIVE LINE.
STRONGER HEATING WILL ALSO OCCUR OVER MUCH OF OK WHERE FEWER CLOUDS
ARE PRESENT...AND AS MOISTURE SPREADS NWD IN ASSOCIATION WITH THE
WARM FRONT...SURFACE DEWPOINTS IN THE LOW/MID 60S WILL BECOME MORE
COMMON OVER PARTS OF CENTRAL/ERN KS INTO WEST CENTRAL/SWRN MO BY
LATER THIS AFTERNOON AND EVENING. 12Z REGIONAL RAOBS EXHIBIT STEEP
MID LEVEL LAPSE RATES WHICH WILL ENHANCE INSTABILITY...WITH MLCAPE
REACHING 1500-2000 J/KG. HOWEVER...THE ASSOCIATED EML WILL LIKELY
CAP DEVELOPMENT OF SURFACE BASED STORMS OVER MUCH OF OK...WITH
PRIMARY TSTM ACTIVITY SPREADING ACROSS PARTS OF KS INTO MO.
FAVORABLE DEEP LAYER SHEAR /40-50 KT OVER THE LOWEST 6 KM/ WILL
PROMOTE DEVELOPMENT OF SUPERCELLS...AND SUFFICIENT LOW LEVEL
SHEAR/SRH COUPLED WITH LOW LCL HEIGHTS SUGGEST POTENTIAL FOR
TORNADIC SUPERCELLS TO DEVELOP...ESPECIALLY ALONG/NEAR THE WARM
FRONT WHERE A FEW STRONG TORNADOES WILL BE POSSIBLE. VERY LARGE
HAIL AND DAMAGING WIND GUSTS WILL ALSO BE POSSIBLE AS STORMS
PROGRESS EWD INTO WRN MO BY EVENING. THE ACTIVITY IS EXPECTED TO
GRADUALLY WEAKEN AFTER 03Z AS DIURNAL BOUNDARY LAYER COOLING OCCURS.


...NERN GA INTO SC...
RELATIVELY FEW CLOUDS WILL ALLOW STRONG HEATING TO OCCUR THIS
AFTERNOON AS A COLD FRONT SETTLES SWD ACROSS THE AREA. SURFACE DEW
POINTS NEAR 60F WILL PERMIT DEVELOPMENT OF STEEP LOW LEVEL LAPSE
RATES IN THE PRE-CONVECTIVE ENVIRONMENT. MODEL GUIDANCE IS
CONSISTENT INDICATING STORMS WILL DEVELOP IN A CORRIDOR FROM THE SRN
APPALACHIANS ACROSS SC THIS AFTERNOON AS A WEAK PERTURBATION IN THE
MID/UPPER LEVEL FLOW TRAVERSES THE REGION. WINDS ALOFT/DEEP LAYER
SHEAR WILL BE SUFFICIENTLY STRONG TO SUPPORT ORGANIZED MULTI-CELL
CONVECTION...WITH STRONGER CELLS CAPABLE OF PRODUCING LARGE HAIL AND
STRONG WIND GUSTS. THE SEVERE THREAT IS EXPECTED TO DIMINISH AFTER
SUNSET.

..WEISS/MOSIER.. 04/27/2012

[WeatherMonger]

PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1128 AM CDT FRI APR 27 2012

...SEVERE THUNDERSTORMS EXPECTED OVER PARTS OF CENTRAL AND EASTERN
KANSAS AND WEST CENTRAL MISSOURI THIS AFTERNOON AND EVENING...

THE NWS STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING THE
DEVELOPMENT OF A FEW STRONG TORNADOES AND LARGE DESTRUCTIVE HAIL
OVER PARTS OF CENTRAL AND EASTERN KANSAS AND WEST CENTRAL MISSOURI
THIS AFTERNOON AND EVENING.

THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE

CENTRAL AND EASTERN KANSAS
WEST CENTRAL MISSOURI

ELSEWHERE...SEVERE STORMS ARE ALSO POSSIBLE SURROUNDING THE GREATEST
RISK AREA...FROM WEST CENTRAL PORTIONS OF KANSAS EASTWARD INTO
CENTRAL AND SOUTHWEST MISSOURI.

A STRONG UPPER LEVEL STORM SYSTEM IS FORECAST TO MOVE FROM WESTERN
KANSAS LATE THIS MORNING TO THE LOWER MISSOURI RIVER VALLEY BY THIS
EVENING. A WARM AND INCREASINGLY MOIST AND DESTABILIZING LOW LEVEL
AIR MASS WILL SPREAD NORTHWARD INTO THE AREA AS A WARM FRONT MOVES
INTO KANSAS. AS THIS OCCURS...WINDS ALOFT WILL STRENGTHEN AND
BECOME MORE FAVORABLE FOR AN EPISODE OF SEVERE THUNDERSTORMS ACROSS
THE MODERATE RISK AREA. THE THREAT FOR SEVERE THUNDERSTORMS WILL
BEGIN THIS AFTERNOON AND FEATURE A RISK FOR LARGE DESTRUCTIVE
HAIL...DAMAGING STRAIGHT-LINE WINDS...AND THE POSSIBILITY OF A FEW
STRONG TORNADOES. BY THIS EVENING...THE SEVERE RISK WILL SHIFT
EASTWARD INTO PORTIONS OF EASTERN KANSAS AND WESTERN MISSOURI...WITH
AN ATTENDANT RISK FOR LARGE HAIL...DAMAGING WINDS...AND A FEW STRONG
TORNADOES.

STATE AND LOCAL EMERGENCY MANAGERS ARE MONITORING THIS DEVELOPING
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.

..WEISS.. 04/27/2012

[jdrenken]

Multi-Media brief

[jdrenken]

SGF Multi-media Brief

[jdrenken]

700mb temps are pushing 11C as far North as Independence, KS. Gonna need more moxie to break the cap.

[WeatherMonger]

700mb temps are pushing 11C as far North as Independence, KS. Gonna need more moxie to break the cap.

Completely expected correct? Outlook mentioned capping holding storms down in OK, or is it progressing further north than forecast?

[jdrenken]

New MD regarding further northeast placement of a tornado watch.

MESOSCALE DISCUSSION 0605
NWS STORM PREDICTION CENTER NORMAN OK
0129 PM CDT FRI APR 27 2012

AREAS AFFECTED...N-CNTRL TO SERN KS

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

VALID 271829Z - 272000Z

SEVERE THREAT IS STILL EXPECTED TO INCREASE THIS AFTERNOON...BUT
APPEARS TO BE DELAYED IN TIMING AS TSTM INITIATION IN S-CNTRL KS HAS
BEEN CURTAILED BY STRONG SUBSIDENCE. WITH STRONGER HEATING NOW
OCCURRING AHEAD OF THE DRYLINE...CONVECTION WILL GROW ACROSS N-CNTRL
KS AND EVENTUALLY DEVELOP S/SEWD TOWARDS SERN KS. A TORNADO WATCH
WILL LIKELY BE ISSUED BETWEEN 19-21Z.

SUBSTANTIAL DRYING NOTED IN WATER VAPOR IMAGERY HAS SPREAD ACROSS
S-CNTRL KS WITH LARGE-SCALE SUBSIDENCE S OF THE COMPACT SHORT WAVE
IMPULSE OVER NWRN KS. THIS APPEARS TO BE THE PRIMARY LIMITING FACTOR
SUPPRESSING TSTM DEVELOPMENT THUS FAR S OF THE IMMEDIATE VICINITY OF
THE TRIPLE POINT /LOCATED AROUND 30 S HLC AT 18Z/. WITH INDIVIDUAL
CELL MOTIONS SHIFTING N/NEWD OF THE SURFACE WARM FRONT THAT ARCED
SEWD INTO SERN KS...CONVECTION THUS FAR HAS STRUGGLED TO REACH
SEVERE INTENSITY. 12Z CONVECTION-ALLOWING WRF AND RECENT HRRR RUNS
SUGGEST THAT CONVECTION MAY REMAIN TIED ALONG AND JUST N OF THE WARM
FRONT IN THE LOBE OF ASCENT ASSOCIATED WITH THE SHORT WAVE IMPULSE.
STILL...WITH A 50 MILE WIDE AREA OF STRONGER HEATING OCCURRING
BETWEEN THE DRYLINE AND REMNANT STRATUS DECK IN CNTRL KS...THIS
SHOULD PROVE FAVORABLE FOR SUSTAINING DEVELOPMENT OF A FEW
SUPERCELLS WITH ATTENDANT LARGE HAIL/TORNADO THREATS.

..GRAMS.. 04/27/2012