Apr 8, 2015 0600 UTC Day 1 Convective Outlook

DAY 1 CONVECTIVE OUTLOOK  
  

NWS STORM PREDICTION CENTER NORMAN OK
   0100 AM CDT WED APR 08 2015

   VALID 081200Z - 091200Z

   ...THERE IS AN ENH RISK OF SVR TSTMS FROM A PORTION OF OK THROUGH
   SERN KS...MO INTO WRN IL...

   ...THERE IS A SLGT RISK OF SVR TSTMS FROM A PORTION OF THE SRN AND
   CNTRL PLAINS INTO THE MID MS VALLEY AND OH VALLEY REGIONS...

   ...THERE IS A MRGL RISK OF SVR TSTMS FROM A PORTION OF THE SRN AND
   CNTRL PLAINS THROUGH THE MID MS AND OH VALLEYS...

   ...SUMMARY...
   SEVERE STORMS ACCOMPANIED BY A RISK FOR VERY LARGE HAIL...DAMAGING
   WIND AND A FEW TORNADOES ARE EXPECTED ACROSS PARTS OF THE CENTRAL
   PLAINS AND LOWER MISSOURI VALLEY WEDNESDAY AFTERNOON AND EVENING.
   OTHER STRONG TO SEVERE STORMS MAY DEVELOP OVER A PORTION OF THE OHIO
   VALLEY.

   ...SYNOPSIS...

   A LOW-AMPLITUDE PROGRESSIVE SYNOPTIC REGIME WILL CHARACTERIZE THE
   UPPER PATTERN WEDNESDAY. UPPER TROUGH NOW MOVING TOWARD THE GREAT
   BASIN AREA WILL REACH THE CNTRL HIGH PLAINS WEDNESDAY EVENING. AN
   UPPER JET STREAK APPROACHING THE NRN BAJA SHOULD REACH THE SRN
   PLAINS DURING THE AFTERNOON. 

   AT SFC A QUASI-STATIONARY FRONT NOW EXTENDS FROM THE OH VALLEY WWD
   TO A SFC LOW OVER NRN MO...SWWD INTO NWRN OK AND THE TX PANHANDLE.
   WRN PORTION OF THIS BOUNDARY WILL LIFT NWD AS A WARM FRONT INTO
   SRN/CNTRL KS LATER WEDNESDAY AFTERNOON AS A LEE LOW BECOMES
   ESTABLISHED OVER THE CNTRL HIGH PLAINS. DRYLINE WILL SHARPEN FROM
   SWRN KS INTO THE ERN TX PANHANDLE...SWD THROUGH WRN TX AND MIX EWD
   INTO WRN OK BEFORE RETREATING WWD DURING THE EVENING. A PACIFIC
   FRONT WILL EVENTUALLY MERGE WITH THE DRYLINE FROM KS THROUGH WRN TX
   WEDNESDAY NIGHT.

   ...SRN AND CNTRL PLAINS THROUGH THE LOWER MO VALLEY...

   PARTIALLY MODIFIED GULF AIR IS IN PLACE OVER THE SRN PLAINS...AND
   LOW-LEVEL LOW TO MID 60S F DEWPOINTS SHOULD CHARACTERIZE MUCH OF THE
   WARM SECTOR DURING THE AFTERNOON. THE 00Z WED RAOBS INDICATE AN EML
   WITH STEEP LAPSE RATES HAS ALREADY ADVECTED ABOVE MUCH OF THIS
   REGION...AND DIABATIC WARMING OF THE BOUNDARY LAYER SHOULD BOOST
   MLCAPE TO 2500-3500 J/KG WEDNESDAY AFTERNOON. ELEVATED STORMS MAY
   DEVELOP EARLY IN THE PERIOD NORTH OF THE STALLED FRONT FROM ERN KS
   INTO MO...AND SOME OF THIS ACTIVITY MAY POSE A THREAT FOR LARGE
   HAIL. CURRENT INDICATIONS ARE THAT MOST OF THE WARM SECTOR WILL
   REMAIN CAPPED MUCH OF THE DAY. SOME MODEL SOLUTIONS INITIATE STORMS
   BY EARLY AFTERNOON FROM NRN TX INTO OK...BUT THIS ACTIVITY MIGHT BE
   MID-LEVEL CONVECTION ROOTED ABOVE THE CAP AND DEVELOPING IN RESPONSE
   TO THE SRN-STREAM JET STREAK. 

   CURRENT THINKING IS THAT SFC-BASED STORMS WILL INITIATE ALONG THE
   DRYLINE-FRONT INTERSECTION OVER NCNTRL OK OR SCNTRL KS BY LATE
   AFTERNOON...WHILE OTHER MORE ISOLATED ACTIVITY MAY DEVELOP FARTHER
   SW FROM THE ERN TX PANHANDLE INTO WRN TX WITHIN ZONE OF DEEP MIXING
   ALONG THE DRYLINE. DEEP-LAYER SHEAR PROFILES WILL STRENGTHEN TO
   40-50 KT WITH APPROACH OF THE MID-LEVEL JET STREAK SUPPORTIVE OF
   SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL. THREAT FOR
   TORNADOES /A COUPLE OF WHICH COULD BE STRONG/ WILL ALSO INCREASE BY
   LATE AFTERNOON INTO THE EARLY EVENING AS THE LLJ STRENGTHENS IN
   ASSOCIATION WITH DEEPENING LEE LOW. ACTIVITY IS EXPECTED TO DEVELOP
   NEWD THROUGH THE MID MS VALLEY AREA DURING THE EVENING WITH A
   CONTINUED THREAT FOR LARGE HAIL...DAMAGING WIND AND A FEW TORNADOES.
   GIVEN THE POTENTIAL FOR SIGNIFICANT SEVERE...AN UPGRADE TO MODERATE
   RISK MIGHT BE NEEDED IN LATER UPDATES ONCE MORE CONFIDENCE IS GAINED
   REGARDING STORM COVERAGE/EVOLUTION. 

   ...OH VALLEY AREA...

   STORMS ARE EXPECTED TO DEVELOP ONCE AGAIN WITHIN THE MODERATELY
   UNSTABLE WARM SECTOR OVER THE OH VALLEY GENERALLY ALONG AND SOUTH OF
   THE QUASI-STATIONARY FRONT AS THE BOUNDARY LAYER DESTABILIZES.
   EFFECTIVE-SHEAR PROFILES FROM 30-40 KT WILL SUPPORT STORM
   ORGANIZATION INCLUDING POTENTIAL FOR BOTH MULTICELLS AND SUPERCELLS
   WITH DAMAGING WIND AND LARGE HAIL THE MAIN THREATS.

   ..DIAL/GLEASON.. 04/08/2015