Heres the offical SPC heads up the night before indicating this would evolve into a PDS, or particularly dangerous situation. Heres the release around 2:42pm.
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0242 PM CDT SAT APR 14 2012
VALID 142000Z - 151200Z
...THERE IS A HIGH RISK OF SVR TSTMS FOR CNTRL AND ERN KS AND
NEB...AND MUCH OF NRN OK...
...THERE IS A MDT RISK OF SVR TSTMS FROM CNTRL OK NWD ACROSS
KS...NEB...SWRN IA AND NWRN MO...
...THERE IS A SLGT RISK OF SVR TSTMS FROM N TX INTO SERN SD AND SRN
MN...
...OK/KS...
VISIBLE SATELLITE IMAGERY SHOWS THICK STRATUS RELATED TO THE
ADVECTION OF MID 60S F BOUNDARY LAYER DEWPOINTS FROM NRN TX INTO
CNTRL OK AND CNTRL KS...WITH SSELY SURFACE WINDS GUSTING OVER 30
MPH. A SPECIAL 17Z OUN SOUNDING SHOWS THE PRESENCE OF A WARM LAYER
NEAR 650 MB...WITH RELATIVELY COOL...BUT MOIST...PROFILES IN THE
LOWEST 3 KM. LATEST RUC FORECAST SOUNDINGS INDICATES CAPPING
INCREASING AFTER 21Z OVER PORTIONS OF SRN AND ERN OK. THUS...THE
THREAT APPEARS MORE CONDITIONAL THERE...BUT VERY CLOSE TO THE EDGE
OF THE ONGOING HIGH RISK AREA. THUS...NO CHANGES WILL BE MADE.
TO THE W...CLEARING WAS TAKING PLACE ALONG AND E OF THE DRYLINE FROM
SW KS INTO THE OK AND TX PANHANDLES AND WRN OK. SURFACE OBSERVATIONS
SHOWED TEMPERATURES RISING INTO THE MID TO UPPER 70S OVER WRN
OK...AND AT OR ABOVE 80 F IN THE PANHANDLES. AS A RESULT...THE
ATMOSPHERE HAS BECOME UNCAPPED IN THESE AREAS. INDEED...SEVERE
STORMS WERE ALREADY ONGOING OVER WRN KS INTO FAR NW OK ALONG THE
DRYLINE...WITH TOWERING CU FARTHER S.
WAVES OF STORMS SHOULD CONTINUE TO FORM ON THE DRYLINE...WHERE
CONVERGENCE IS INCREASING AS SURFACE WINDS VEER OVER THE PANHANDLES.
THESE STORMS SHOULD BECOME PROGRESSIVELY MORE SEVERE...AS LOW LEVEL
SHEAR CONTINUES TO INCREASE ACROSS THE WARM SECTOR. FORECAST
SOUNDINGS SUGGEST THAT UPPER 70S TO LOWER 80S TEMPERATURES WILL BE
NEEDED TO INITIATE STORMS.
MEANWHILE...LATEST RUC MODEL GUIDANCE SUGGESTS THAT COOLING ALOFT
WITH THE UPPER TROUGH MAY BE MORE ADVANCED THAT PREVIOUSLY FORECAST
WITH 500 MB TEMPS OF -12 TO -13 C TO THE DRYLINE BY 00Z. THIS WILL
ONLY HELP TO INCREASE UPDRAFT ACCELERATION IN AN ALREADY VOLATILE
SETUP. AT THIS TIME...IT APPEARS THE MOST LIKELY CORRIDOR FOR
VIOLENT TORNADOES WILL BE FROM NW OK ACROSS NRN OK INTO CNTRL AND
S-CNTRL KS. VERY LARGE HAIL WILL ALSO OCCUR. WITH ONGOING CELLS OVER
CNTRL KS...THE LOCATION OF OUTFLOW BOUNDARIES MAY ALSO PLAY A KEY
ROLE IN TORNADOGENESIS AS SUPERCELLS INTERACT WITH THEM LATER. SOME
OF THE CITIES WITH THE HIGHEST RISK INCLUDE ENID...PRATT...GREAT
BEND...SALINA...HUTCHINSON...WICHITA.
...NRN KS/NEB...
LARGE SUPERCELLS ARE ONGOING ACROSS NRN KS...WITH STRONG
MESOCYCLONES NOTED ON RADAR AND PROBABLY TORNADOES. THESE CELLS WILL
CONTINUE TO TREK NEWD INTO NEB WHERE SHEAR REMAINS STRONG AND
INSTABILITY IS SUFFICIENT WITH RELATIVELY COOL TEMPERATURES. IN
ADDITION TO A TORNADO THREAT...SOME OF THESE HP CELLS MAY EVENTUALLY
BOW WITH DAMAGING WIND THREAT AS WELL.
ANOTHER LIKELY AREA OF SUPERCELL TORNADO DEVELOPMENT WILL BE FROM
NWRN KS INTO WRN AND CNTRL NEB. VISIBLE IMAGERY SHOWS A LARGE CU
FIELD...W OF THE ONGOING KS ACTIVITY...AND E OF THE DRYLINE. BACKED
SURFACE FLOW OVER NEB...ALONG WITH CONTINUED HEATING AND COOLING
ALOFT SHOULD PROVE FAVORABLE FOR A DEVELOPING TORNADO AND LARGE HAIL
THREAT. STRONG TORNADOES WILL REMAIN POSSIBLE AREA-WIDE.
...A SIGNIFICANT TORNADO OUTBREAK IS EXPECTED LATER TODAY AND
TONIGHT ACROSS PORTIONS OF NEBRASKA...KANSAS...AND OKLAHOMA...
A LARGE UPPER TROUGH REMAINS PLACED OVER THE WESTERN UNITED STATES
TODAY...WITH A STRONG MID/UPPER LEVEL JET EXTENDING FROM THE
SOUTHWEST STATES INTO THE CENTRAL PLAINS. WATER VAPOR IMAGERY AND
MORNING MODEL SOLUTIONS SUGGEST SEVERAL SUBTLE SHORTWAVE TROUGHS
EMBEDDED IN THE FASTER FLOW. THIS WILL RESULT IN THE POTENTIAL FOR
MULTIPLE ROUNDS OF SEVERE WEATHER OVER THE CENTRAL PLAINS TODAY.
THE FIRST CLUSTER OF SEVERE STORMS HAS NOW FORMED OVER SOUTHWEST KS
AND WILL LIKELY SPREAD NORTHEASTWARD INTO NEB THIS AFTERNOON AND
EVENING. THESE STORMS WILL BE IN AN INCREASINGLY VOLATILE AIR MASS
AS DAYTIME HEATING AND LOW LEVEL MOISTURE ADVECTION DESTABILIZE THE
REGION. LARGE HAIL AND DAMAGING WINDS ARE THE EARLY THREATS...BUT
AN INCREASING RISK OF SURFACE-BASED SUPERCELLS WILL POSE A THREAT OF
TORNADOES BY EARLY AFTERNOON. AS THE ACTIVITY MOVES INTO SOUTHERN
NEB...EVEN STRONGER LOW LEVEL SHEAR SUGGESTS THAT THE POTENTIAL FOR
STRONG TORNADOES WILL BE ENHANCED.
STRONG HEATING IS EXPECTED TO OCCUR ALONG THE DRYLINE LATER THIS
AFTERNOON AND EARLY EVENING OVER WESTERN KS INTO WESTERN OK. MODEL
SOLUTIONS SUGGEST THE CAP WILL BE WEAK BUT CONSIDERABLE UNCERTAINTY
REMAINS REGARDING THE EXTENT OF LARGE SCALE FORCING THIS EVENING.
AREAL COVERAGE OF STORMS COULD BE WIDELY SPACED. HOWEVER...
PARAMETERS TO THE EAST OF THE DRYLINE WILL BE EXTREMELY FAVORABLE
FOR TORNADIC SUPERCELLS CAPABLE OF LONG-TRACK... DAMAGING/VIOLENT
TORNADOES /4000 J/KG MLCAPE...50-60 KNOTS OF EFFECTIVE SHEAR...AND
0-3KM SRH VALUES OF 300-500 M2/S2/. THOSE STORMS THAT FORM MAY
PERSIST FOR SEVERAL HOURS AND TRACK ACROSS CENTRAL KS/OK AND INTO
SOUTHERN NEB.
FARTHER SOUTH...CONVECTIVE INITIATION BECOMES INCREASINGLY
UNCERTAIN. HOWEVER...WEAK CONVERGENCE ALONG THE DRYLINE COUPLED
WITH A WEAK CAP AND STEEP LOW LEVEL LAPSE RATES SUGGEST SOME THREAT
OF ISOLATED SEVERE STORMS ACROSS PARTS OF WESTERN NORTH TX.
Wicked setup for the day and I imagined every chaser across the US were heading for encounter! So, heres the SPC's maps for the day. It looks like todays gonna be a great day!
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