Severe Storm Outlook Narrative (AC)
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574
ACUS02 KWNS 290447
SWODY2
SPC AC 290446

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1146 PM CDT THU APR 28 2016

VALID 301200Z - 011200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF MO/SRN IL TO
SERN TX...

...THERE IS A MRGL RISK OF SVR TSTMS SURROUNDING THE IMMEDIATE SLGT
RISK...

...SUMMARY...
STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS THE MID
MISSISSIPPI VALLEY SATURDAY WITH MORE ISOLATED ACTIVITY EXPECTED
ACROSS THE LOWER MISSISSIPPI VALLEY AND SOUTHEASTERN TEXAS.

...MS VALLEY...

SWRN U.S. UPPER TROUGH IS EXPECTED TO MOVE INTO THE PLAINS BY
SUNRISE SATURDAY MORNING AS H5 SPEED MAX TRANSLATES INTO THE
ARKLATEX.  EXIT REGION OF THIS FEATURE SHOULD FOCUS ASCENT OVER THE
MIDDLE MS VALLEY REGION DURING THE FIRST HALF OF THE PERIOD.

LOW-LEVEL WARM ADVECTION WILL LIKELY BE RESPONSIBLE FOR EARLY-DAY
CONVECTION ALONG/NORTH OF WARM FRONT THAT WILL BE DRAPED NEAR THE
I-70 CORRIDOR FROM MO INTO INDIANA.  CONVECTIVE UPDRAFTS SHOULD BE
ROOTED NEAR 850MB AND INSTABILITY COULD PROVE ADEQUATE FOR SMALL
HAIL.  HOWEVER...MORE ROBUST UPDRAFTS ARE EXPECTED TO DEVELOP LATER
IN THE DAY IMMEDIATELY AHEAD OF WEAK SFC LOW WHERE STRONG
BOUNDARY-LAYER HEATING IS EXPECTED.  WHILE LOW-LEVEL FLOW IS
EXPECTED TO VEER ACROSS THE WARM SECTOR IT APPEARS ISOLATED
THUNDERSTORMS WILL EVOLVE AS SFC PARCELS APPROACH THEIR CONVECTIVE
TEMPERATURES.  FORECAST SOUNDINGS FAVOR DISCRETE SUPERCELLS BUT WEAK
LOW-LEVEL SHEAR SUGGESTS HAIL WILL BE THE PRIMARY SEVERE THREAT.

FARTHER SOUTH...SUBSTANTIAL HIGH-LEVEL FLOW WILL TRANSLATE ACROSS
THE LOWER MS VALLEY DURING THE DAY AS SPEED MAX MOVES INTO NRN MS BY
01/00Z.  ENTRANCE REGION OF THIS JET MAY ENHANCE CONVECTIVE THREAT
ALONG WEAKLY CONVERGENT SFC BOUNDARY THAT SHOULD BE DRAPED ACROSS
EAST TX DURING THE PERIOD.  FORECAST SOUNDINGS SUGGEST SUPERCELLS
ARE POSSIBLE ACROSS THIS REGION WHERE ENVIRONMENTAL SHEAR IS
ADEQUATELY STRONG...SFC-6KM BULK SHEAR ON THE ORDER OF 40KT.
CORRIDOR OF STRONGEST BUOYANCY WILL EXTEND ACROSS EAST TX INTO SWRN
AR AND CONVECTION THAT EVOLVES COULD PRODUCE LARGE HAIL.

..DARROW.. 04/29/2016

$$



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