[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 082027
SWODY2
SPC AC 082026

DAY 2 CONVECTIVE OUTLOOK CORR 1
NWS STORM PREDICTION CENTER NORMAN OK
0326 PM CDT MON MAY 08 2006

VALID 091200Z - 101200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN PLAINS
AND ACROSS THE LOWER MS VALLEY...

CORRECTED FOR NDFD PROBS

...SYNOPSIS...
AN ACTIVE SEVERE WEATHER PATTERN APPEARS TO BE SETTING UP FOR
TUESDAY. DETAILS WITH REGARD TO WHERE GREATEST SEVERE POTENTIAL WILL
EVOLVE ARE NOT YET CLEAR. HOWEVER...CHANCES FOR SEVERE STORMS SHOULD
INCREASE FROM THE TX/OK PNHDLS EWD ACROSS THE OZARKS DURING THE DAY
AND EVENING TUESDAY.

A NRN BRANCH MID/UPPER LEVEL TROUGH WILL UNDERGO AMPLIFICATION
ACROSS THE NRN AND CNTRL PLAINS THROUGH TUESDAY AS A NUMBER OF
SMALLER SCALE PERTURBATIONS ROTATE THROUGH THE LARGE SCALE CYCLONIC
FLOW FROM THE ROCKIES TO THE MS VALLEY.

AT THE SURFACE...VARIOUS MCS OUTFLOW BOUNDARIES WILL BE INTERSPERSED
WITH SYNOPTIC FRONTAL ZONES FROM THE SRN PLAINS/OZARKS NWD TO THE
UPPER MS VALLEY. LATEST MODEL GUIDANCE WAS IN RELATIVELY GOOD
AGREEMENT THAT ONE MCS WILL BE LOCATED OVER THE OZARKS EARLY TUESDAY
WITHIN WARM CONVEYOR BELT AHEAD OF LEE-TROUGH AND SRN PLAINS COLD
FRONT. ANOTHER MCS MAY BE ONGOING EARLY IN THE PERIOD ACROSS MN/WI
NEAR A MID LEVEL SHORT WAVE TROUGH BEING EJECTED EWD AHEAD OF NEXT
STRONG UPSTREAM SYSTEM DEVELOPING EAST FROM THE ROCKIES/HIGH PLAINS.


SYNOPTIC FRONTS WILL ALSO INCLUDE A WARM FRONT EXTENDING FROM THE
MCS OVER ERN OK/OZARKS SEWD TO THE DEEP SOUTH...AND A SECONDARY COLD
FRONT ASSOCIATED WITH THE NRN BRANCH SYSTEM DEVELOPING SEWD ACROSS
THE NRN/CNTRL PLAINS.

LARGE SCALE HEIGHT FALLS AND DIFFERENTIAL HEATING WILL REINFORCE THE
SRN PLAINS COLD FRONT FROM SERN CO TO THE NRN TX PNHDL AND INTO NWRN
OK BY LATE AFTERNOON. MEANWHILE...DRYLINE WILL SHARPEN OVER THE ERN
TX PNHDL AS TRIPLE POINT LOW EVOLVES ACROSS NWRN TX/SWRN OK.
STRENGTHENING MESOSCALE FORCING ASSOCIATED WITH THESE
FEATURES...COUPLED WITH INCREASING INSTABILITY AND SHEAR...SHOULD
PROMOTE WIDESPREAD SEVERE TSTM ACTIVITY FROM THE SRN PLAINS TO THE
LOWER MS VALLEY THROUGH TUESDAY NIGHT.

...SRN PLAINS/OZARKS EAST ACROSS THE LOWER MS VALLEY...
MCS EVOLUTION ACROSS THE PLAINS THROUGH TUESDAY MORNING WILL PLAY A
SIGNIFICANT ROLE IN SEVERE WEATHER FORMATION AND STORM MODE ACROSS
PARTS OF OK AND AR LATER TUESDAY AFTERNOON. GIVEN THAT THE MCS HAS
YET TO FORM...AND CONVECTIVE INHIBITION ACROSS THE WARM SECTOR MAY
BE QUITE STRONG WITH 700MB TEMPERATURES AROUND 10C...A LOWER
CONFIDENCE FORECAST SUGGESTS MAINTAINING ONLY A SLGT RISK AT THIS
TIME.

LATEST GUIDANCE DOES SUGGEST THAT AN MCS OR TWO WILL BE ONGOING OVER
THE MID-MS VLY SWWD INTO THE OZARKS. OUTFLOW BOUNDARY SHOULD
REINFORCE THE WARM FRONT ACROSS SRN OK SEWD ACROSS SRN AR.
DESTABILIZATION AHEAD OF THE MCS...AND ALONG THE WARM FRONT TO THE
TN VALLEY...COULD RESULT IN STRONG TO SEVERE STORMS CONTINUING... OR
REDEVELOPING...EWD ACROSS THESE AREAS THROUGH THE DAY. DAMAGING
WINDS...SOME HAIL...AND PERHAPS EVEN A TORNADO OR TWO COULD OCCUR
WITH THIS ACTIVITY.

THE SWRN FLANK OF THE MCS WILL PROBABLY WEAKEN AS CONVECTIVE
INHIBITION STRENGTHENS ACROSS THE WARM SECTOR. HOWEVER...STRONG SWLY
LLJ WILL CONTINUE TO TRANSPORT VERY UNSTABLE PARCELS ACROSS THE COLD
POOL...AND CONVECTIVE CLUSTER WITH SOME HAIL POTENTIAL MAY PERSIST
ACROSS PARTS OF AR DURING THE MORNING.

SUBSIDENCE AND CAPPING IN WAKE OF THE MCS WILL ALLOW FOR THE
DEVELOPMENT OF STRONG DESTABILIZATION ACROSS TX/OK THROUGH THE
DAY WITH GREATEST CHANCE FOR STORM INITIATION OCCURRING BY AFTERNOON
ALONG/NORTH OF REMNANT OUTFLOW...ACROSS WRN AR TO NRN OK. A
SECONDARY AREA FOR STORM DEVELOPMENT SHOULD EVOLVE NEAR THE COLD
FRONT/DRYLINE TRIPLE POINT...OR NORTH OF THESE FEATURES WHERE
INCREASING LARGE SCALE FORCING FROM AMPLIFYING FLOW/HEIGHT FALLS
WILL OVERCOME INHIBITION. EFFECTIVE SHEAR WILL BE MORE THAN
SUFFICIENT FOR SUPERCELLS WITH VERY LARGE HAIL AND DAMAGING WINDS. 
TORNADOES WILL ALSO BE POSSIBLE...MAINLY ACROSS PARTS OF NRN/ERN OK
AND PERHAPS WRN AR...WHERE POST-OUTFLOW/FRONT ELY FLOW WILL RESULT
IN ENLARGED HODOGRAPHS.

FARTHER SOUTH ALONG ADVANCING DRYLINE...TSTMS WILL LIKELY BE MORE
ISOLATED GIVEN STRONG CAP AND WEAKER LARGE SCALE FORCING.

EXPECT SEVERAL TSTMS CLUSTERS WILL GROW UPSCALE INTO MCS/S TUE
NIGHT/EARLY WED...PROBABLY FROM THE OZARKS INTO THE LWR MS VLY...AND
FROM THE SRN HIGH PLAINS ACROSS OK AND NRN TX. GIVEN AVAILABLE
INSTABILITY FEEDING INTO THESE STORMS...THREAT FOR HAIL/HIGH WINDS
MAY PERSIST WELL AFTER DARK AND INTO EARLY WEDNESDAY.

...UPPER MS VLY...
IN WAKE OF MORNING CONVECTION...BOUNDARY LAYER SHOULD RECOVER
ALONG/AHEAD OF THE COLD FRONT ACROSS PORTIONS OF THE UPPER MS VLY.
RESIDUAL SFC DEW POINTS IN THE 50S BENEATH STEEPENING LAPSE RATES
ALOFT ASSOCIATED WITH APPROACHING LARGE SCALE TROUGH WILL BE
FAVORABLE FOR TSTM INITIATION ACROSS PORTIONS OF MN. VERTICAL SHEAR
WILL BE WEAK AND GIVEN NATURE OF FORCING...EVOLUTION INTO LINE
SEGMENTS IS LIKELY. A COUPLE OF DAMAGING WIND/HAIL EVENTS MAY
ACCOMPANY THE STRONGER STORMS. EXPECT SEVERE THREAT TO WANE DURING
THE EVENING HOURS.

..CARBIN.. 05/08/2006