[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 151730
SWODY2
SPC AC 151729

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1229 PM CDT TUE AUG 15 2006

VALID 161200Z - 171200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
PROGRESSIVE NRN STREAM SHORTWAVE PATTERN WILL CONTINUE THROUGH
PERIOD IN MID/UPPER LEVELS...DOWNSTREAM FROM AMPLIFYING TROUGH OVER
PACIFIC NW.  BROAD FETCH OF SWLY FLOW ALOFT...FROM NRN GREAT BASIN
ACROSS NRN ROCKIES AND NRN HIGH PLAINS...WILL CONTRIBUTE TO LEE-SIDE
PRESSURE FALLS AND LOW LEVEL WAA ACROSS CENTRAL/NRN HIGH PLAINS.  BY
17/00Z...QUASISTATIONARY FRONTAL ZONE IS EXPECTED FROM SRN MB SWWD
INTO CENTRAL WY.  SFC FRONTAL ZONE -- STRONGLY MODULATED BY
CONVECTIVE OUTFLOWS -- SHOULD LINGER FROM VA/NC TIDEWATER REGION
SWWD ACROSS MS...BECOMING DIFFUSE NWWD ACROSS CENTRAL PLAINS.

FARTHER S...SHORTWAVE TROUGH -- EVIDENT IN MOISTURE CHANNEL IMAGERY
OVER NWRN MEX -- MAY LIFT NEWD ACROSS PORTIONS SRN ROCKIES AND/OR
SRN HIGH PLAINS DURING PERIOD. MEANWHILE...TROUGH NOW OVER NM
SHOULD LIFT NEWD ACROSS PORTIONS NEB/IA.  PROGS ARE VERY
INCONSISTENT WITH SRN FEATURE...WHICH IS NOT SURPRISING GIVEN ITS
ORIGIN IN RELATIVE VOID OF MEX UPPER AIR DATA. THEREFORE
CONSIDERABLE UNCERTAINTY REMAINS WITH ITS POTENTIAL TRACK...AND BY
EXTENSION...GEN THUNDER POTENTIAL WITHIN ASSOCIATED PLUME OF LARGE
SCALE ASCENT.

...CENTRAL/NRN PLAINS...
LOW LEVEL MOISTURE IS EXPECTED TO INCREASE WITH SWD
EXTENT...REMAINING MRGL OVER NRN PLAINS WITH DEW POINTS UPPER 40S TO
UPPER 50S F...BUT WITH 60S TO LOW 70S OVER PORTIONS KS.  BY
CONTRAST...MID/UPPER LEVEL LAPSE RATES AND DEEP-LAYER SHEAR
GENERALLY SHOULD INCREASE WITH NWRN EXTENT.  CAP MAY WEAKEN DURING
MID-LATE AFTERNOON SUFFICIENTLY FOR TSTMS OVER PORTIONS CENTRAL/ERN
MT...DAKOTAS...NEB AND WRN/NRN KS.  BOUNDARY LAYER FORCING FOR
SFC-BASED CONVECTION APPEARS RATHER ILL-DEFINED S OF FRONT AND AWAY
FROM POSTFRONTAL OROGRAPHIC LIFT ZONE IN MT.  CONVERGENCE IS NOT
EXPECTED TO BE PARTICULARLY STRONG ALONG FRONT...WHILE MOISTURE WILL
BE IN QUESTION OVER OROGRAPHIC LIFT REGION.  GIVEN THESE OFFSETS IN
MOST FAVORABLE INGREDIENTS FOR SVR POTENTIAL...AND CONVECTIVE
SPATIAL/COVERAGE UNCERTAINTIES...WILL KEEP UNCONDITIONAL SVR
PROBABILITIES BELOW CATEGORICAL OUTLOOK CRITERIA ATTM.

...SERN STATES...
WIDELY SCATTERED TSTMS -- IN PULSE FORM AND IN MULTICELLULAR
CLUSTERS -- ARE EXPECTED ACROSS MUCH OF REGION ALONG AND S OF FRONT.
 CONVECTIVE POTENTIAL ACROSS COASTAL PLAIN OF CAROLINAS MAY BE
INFLUENCED BY POTENTIAL TROPICAL DEVELOPMENT ASSOCIATED WITH AREA OF
LOW LEVEL LOW PRESSURE NOW EVIDENT OVER ATLANTIC SE OF SC COAST. 
SEE NHC OUTLOOKS UNDER WMO HEADER ABNT20 KNHC FOR MORE INFO.  MORE
ROBUST DIURNAL DESTABILIZATION IS FCST FROM GA SWWD ACROSS SRN
PORTIONS MS/AL/LA...WHERE STRONG SFC HEATING AND DEW POINTS 70S F
WILL YIELD MODERATE-STRONG BUOYANCY.  LOCALIZED POTENTIAL FOR
STG-SVR GUSTS MAY DEVELOP...ESPECIALLY WITH TSTMS DEVELOPING INVOF
BOUNDARIES RELATED TO OUTFLOW...SEA BREEZE AND RESIDUAL SYNOPTIC
FRONT.

...INTERIOR NWRN CONUS...
STRONG LARGE SCALE ASCENT/COOLING WILL OCCUR AHEAD OF DIGGING
MID/UPPER LEVEL TROUGH...RESULTING IN STEEPENED LOW/MIDDLE LEVEL
LAPSE RATES...IN TANDEM WITH DAYTIME SFC HEATING.  THIS SHOULD
RESULT IN WEAK AFTERNOON CINH AND POTENTIAL FOR WIDELY SCATTERED
TSTMS TO DEVELOP...IN ENVIRONMENT OF AT LEAST MRGL BOUNDARY LAYER
MOISTURE.  STRONGEST ACTIVITY MAY PRODUCE HAIL AND/OR GUSTS NEAR
SEVERE LEVELS.

..EDWARDS.. 08/15/2006