SPC AC 090550

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1250 AM CDT MON MAY 09 2016

   VALID 091200Z - 101200Z

   ...THERE IS AN ENH RISK OF SVR TSTMS ACROSS ERN OK...NERN TX...NWRN
   LA...MUCH OF AR...

   ...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN NEB/SRN IA SWD INTO
   ERN TX...

   ...THERE IS A MRGL RISK OF SVR TSTMS IMMEDIATELY SURROUNDING THE
   SLIGHT RISK AREA...

   ...SUMMARY...
   SEVERE STORMS ARE LIKELY MONDAY INTO MONDAY NIGHT FROM PARTS OF THE
   SOUTHERN AND CENTRAL PLAINS EASTWARD INTO THE LOWER TO MID MISSOURI
   VALLEY...OZARKS AND ARKLATEX. TORNADOES AND VERY LARGE HAIL WILL BE
   POSSIBLE ACROSS THE ENHANCED RISK AREA FROM EASTERN OKLAHOMA AND
   NORTHEASTERN TEXAS INTO CENTRAL ARKANSAS AND NORTHERN LOUISIANA.

   ...SYNOPSIS...
   A SHARPLY DEFINED SHORTWAVE TROUGH WILL ROTATE EWD ACROSS THE SRN
   PLAINS DURING THE DAY AND INTO THE MID TO LOWER MS VALLEY BY LATE
   EVENING...WITH MAIN JET MAX ALOFT EXTENDING FROM ERN TX INTO THE
   ARKLATEX BY 00Z THE 10TH. MEANWHILE...ANOTHER SHORTWAVE TROUGH WILL
   MOVE SWD ACROSS THE NRN ROCKIES...DEEPENING A SFC TROUGH FROM WRN
   OK/KS INTO THE NRN HIGH PLAINS DURING THE AFTERNOON. AHEAD OF THE
   UPPER SYSTEM...A BROAD AREA OF SLY 30-40 KT 850 MB FLOW WILL HELP
   BRING MOISTURE NWD ACROSS THE PLAINS INTO THE MS VALLEY WHICH WILL
   RESULT IN DESTABILIZATION AND AREAS OF PRECIPITATION THROUGHOUT THE
   PERIOD.

   DESPITE THE RAPID MOTION OF THE SRN PLAINS SHORTWAVE...THE DRYLINE
   IS FORECAST TO LAG...LOCATED JUST E OF I-35 BY LATE AFTERNOON AND
   ROUGHLY BENEATH THE MIDLEVEL THERMAL TROUGH WITH COLD TEMPERATURES
   AND STEEP LAPSE RATES. THE MOIST SECTOR SHOULD BE CHARACTERIZED BY
   MID 60S F DEWPOINTS FROM SE OK INTO CNTRL AR...WITH UPPER 60S F
   ADVECTING NWD ACROSS ERN TX. THE GREATEST OVERLAP BETWEEN STRONG
   INSTABILITY...LIFT...AND ENLARGED HODOGRAPHS WILL EXIST ACROSS THE
   ENH RISK AREA DURING THE AFTERNOON AND EVENING.

   ...ERN OK AND THE ARKLATEX INTO AR AND FAR SRN MO AND KS...
   STRONG HEATING OVER MUCH OF THE REGION AND STEEP LAPSE RATES ALOFT
   WILL RESULT IN STRONG INSTABILITY FROM ERN TX NWD ACROSS ERN
   OK...WRN AR AND KS. EARLY DAY STORMS ARE LIKELY TO EXIST NEAR THE
   RED RIVER WHICH WILL THEN SHIFT EWD INTO AR BY AFTERNOON. THIS
   ACTIVITY MAY POSE A WIND AND HAIL THREAT FOR THE DURATION...WITH
   POSSIBLE OUTFLOW FOCUSING NEW STORMS LATER IN THE DAY. LOW-LEVEL
   MOISTURE AND INSTABILITY WILL BE MAXIMIZED BY LATE AFTERNOON...AS
   WILL SHEAR PROFILES WHICH WILL CLEARLY FAVOR SUPERCELLS AND SUPPORT
   TORNADOES GIVEN DISCRETE STORM MODE. THE MOST LIKELY AREA FOR
   TORNADOES WILL BE FAR ERN OK INTO W CNTRL AR...AND PERHAPS SWD
   ACROSS THE ARKLATEX. IN ADDITION...ISOLATED SUPERCELLS MAY ALSO
   MATERIALIZE FARTHER S WITHIN THE MOIST AXIS TOWARD THE SHREVEPORT
   VICINITY. ALTHOUGH CONVERGENCE WILL BE WEAK...RAPID MOISTENING AND
   CONFLUENCE LINES MAY BE ENOUGH TO INITIATE DISCRETE STORMS.

   SEVERE STORM CHANCES ARE MORE CONDITIONAL ALONG THE DRYLINE DURING
   THE MID AFTERNOON NEAR 21Z OVER CNTRL OK INTO CNTRL KS...BUT SEVERAL
   MODELS DO PRODUCE STORMS WHICH WOULD CLEARLY HAVE A LARGE HAIL RISK.

   ...MO INTO WRN IL...
   A DISTURBANCE ALOFT IS FORECAST TO PRECEDE THE MAIN SHORTWAVE
   TROUGH...RAPIDLY MOVING NEWD ACROSS MO WITH SUBSTANTIAL HEIGHT FALLS
   AND LIFT. STRONG WARM ADVECTION WILL DEVELOP BY AFTERNOON IN THE
   WAKE OF EARLY RAIN/WEAK THUNDERSTORMS WHICH WILL RESULT IN
   DESTABILIZATION AND INCREASING SHEAR PROFILES WITH SRH ON THE ORDER
   OF 200-300 M2/S2. WITH A DIFFUSE WARM FRONT IN PLACE...A FEW SEVERE
   STORMS CAPABLE OF HAIL AND ALSO A TORNADO OR TWO CANNOT BE RULED
   OUT. HOWEVER...LACK OF STRONG INSTABILITY AND POTENTIAL FOR AIRMASS
   CONTAMINATION LENDS UNCERTAINTY TO THIS AREA.

   ..JEWELL/COOK.. 05/09/2016

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z