672  
ACUS01 KWNS 281302  
SWODY1  
SPC AC 281300  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0800 AM CDT SAT MAY 28 2016  
 
VALID 281300Z - 291200Z  
   
..THERE IS A SLGT RISK OF SVR TSTMS PORTIONS CENTRAL/SW TX
 
 
...THERE IS A MRGL RISK OF SVR TSTMS ELSEWHERE FROM SW TX TO RED  
RIVER VALLEY REGION...  
 
...THERE IS A MRGL RISK OF SVR TSTMS PORTIOSN MID/UPER MS VALLEY  
REGION...  
   
..SUMMARY
 
 
SCATTERED THUNDERSTORMS...SOME SEVERE...ARE EXPECTED THIS AFTERNOON  
AND EVENING OVER PARTS OF THE EDWARDS PLATEAU REGION AND NEARBY  
AREAS OF CENTRAL AND SOUTHWEST TEXAS. ISOLATED SEVERE THUNDERSTORMS  
MAY FORM OVER PARTS OF THE MIDDLE AND UPPER MISSISSIPPI VALLEY  
REGIONS THIS AFTERNOON.  
   
..SYNOPSIS
 
 
IN MID/UPPER LEVELS...HEIGHTS WILL BE RISING THROUGH MUCH OF PERIOD  
OVER CENTRAL CONUS AND ROCKY MOUNTAIN REGION. WEAK LOW NOW OVER ERN  
NEB IS FCST TO DEVOLVE INTO OPEN-WAVE TROUGH AND SLOWLY EJECT ENEWD  
TODAY...REACHING SWRN MN...WRN IA AND KS/MO BORDER REGION BY 00Z.  
NEAR END OF PERIOD...TROUGH SHOULD REACH TO NEAR DLH...UIN...PAH  
LINE. IN SRN STREAM...WEAK TROUGH WITH BROADLY CYCLONIC FLOW WILL  
SLOWLY MOVE ASHORE CA TONIGHT....PRECEDED BY SHORTWAVE RIDGE  
BUILDING OVER PORTIONS UT/AZ/NM.  
 
AT SFC...LOW ASSOCIATED WITH CENTRAL PLAINS PERTURBATION WAS  
ANALYZED AT 11Z IN YKN/FSD AREA...WITH WAVY WARM FRONT ENEWD THROUGH  
SECONDARY LOW NEAR LSE AND ACROSS S-CENTRAL WI...CENTRAL LOWER MI...  
AND NRN NY. WEAK COLD FRONT ARCHED FROM WRN LOW THROUGH ERN KS...  
CENTRAL OK...NW TX AND SERN NM. ENTIRE AREA OF LOW PRESSURE SHOULD  
MOVE SLOWLY NEWD THROUGH PERIOD...REACHING LS BY 12Z...AND PROBABLY  
CONTINUING TO EXHIBIT MULTIPLE/WEAK PRESSURE MINIMA. WARM FRONT  
SHOULD MOVE NWD ACROSS GREAT LAKES AND INTO CANADA...WHILE TRAILING  
COLD FRONT STALLS AND BECOMES MORE DIFFUSE WITH TIME. OUTFLOW  
BOUNDARY FROM PRIOR MCS ACTIVITY EXTENDS FROM NWRN GULF WNWWD ACROSS  
S-CENTRAL TX BETWEEN SAT-COT AND INTO WEAK SFC LOW AND DRYLINE  
INTERSECTION JUST UPRIVER FROM DRT. THIS BOUNDARY SHOULD RETREAT  
NWD ACROSS SWRN/CENTRAL TX THROUGH PERIOD...PERMITTING NWWD RETURN  
OF RICH GULF MOISTURE WITH DEW POINTS COMMONLY UPPER 60S TO 70S F.  
   
..TX
 
 
HEIGHTS WILL BE RISING SUBSTANTIALLY ACROSS THIS AREA THROUGH  
TONIGHT IN WAKE OF SHORTWAVE TROUGH DEPARTING CENTRAL PLAINS. AS  
SUCH...UPPER SUPPORT FOR CONVECTION WILL BE WEAK AT BEST...THOUGH  
RETURNING LOW-LEVEL MOISTURE AND STRONG SFC HEATING SHOULD  
CONTRIBUTE TO MDT TO LOCALLY EXTREME BUOYANCY...ESPECIALLY NEAR AND  
S OF BOUNDARY. MLCAPE MAY REACH 3500-5000 J/KG OVER PORTIONS  
CENTRAL/S-CENTRAL/SW TX...BENEATH STEEP MIDLEVEL LAPSE RATES. AS  
MLCINH WEAKENS...ESPECIALLY INVOF OUTFLOW BOUNDARY WHERE CONVERGENCE  
WILL BE RELATIVELY MAXIMIZED AMIDST OTHERWISE WEAK LOW-LEVEL FLOW...  
SCATTERED TSTMS SHOULD FORM WITH POTENTIAL FOR LARGE HAIL AND  
DAMAGING GUSTS. 35-40 KT EFFECTIVE-SHEAR MAGNITUDE INDICATES  
POTENTIAL FOR MIXED MODES OF ACTIVITY EARLY...INCLUDING ORGANIZED  
MULTICELLS...SHORT-LIVED/HP SUPERCELLS...AND CLUSTERED CONVECTION.  
THESE MAY ORGANIZE INTO LARGER CLUSTERS OR A SMALL MCS THIS EVENING.  
 
ELSEWHERE OVER THIS REGION...CAPPING COMBINED WITH NEBULOUS FOCI FOR  
CONVECTION INITIATION RENDER POTENTIAL COVERAGE ONLY ISOLATED TO  
WIDELY SCATTERED...AND HEAVILY DEPENDENT ON MORE SUBTLE...MESOBETA-  
AND SMALLER-SCALE BOUNDARIES.  
   
..UPPER MS VALLEY TO NRN MO/WRN IL REGION
 
 
GRADUAL EXPANSION/INTENSIFICATION OF CONVECTION IS EXPECTED THROUGH  
MID/LATE AFTN ACROSS THIS REGION WHILE ENTIRE REGIME SHIFTS  
GENERALLY NEWD. ONE OR MORE ARCS OF CONVECTION MAY DEVELOP FROM  
NRN/ERN MO ACROSS IA TOWARD SERN MN...MOVING INTO PORTIONS IL/WI  
WITH TIME. FRAGMENTED MOISTURE FIELD AND WEAK MID/UPPER-LEVEL LAPSE  
RATES SHOULD KEEP MLCAPE GENERALLY LESS THAN 1000 J/KG OVER MOST OF  
THIS AREA...WHILE DEEP SHEAR REMAINS MRGL AS UPPER SYSTEM WEAKENS.  
MRGLLY SVR HAIL AND LOCALLY DAMAGING GUSTS ARE POSSIBLE FROM MORE  
INTENSE/PERSISTENT CELLS. WHILE TORNADO POTENTIAL CANNOT BE RULED  
OUT INVOF SLOWLY MIGRATING LOW-PRESSURE AREA...WEAKNESS OF THAT AS  
WELL AS OF ASSOCIATED ISALLOBARIC FIELDS AND NEAR-SFC WIND FIELDS  
SHOULD KEEP HODOGRAPHS AND LOW-LEVEL SHEAR VECTORS RELATIVELY SMALL.  
EXCEPTION MAY BE WHERE LOCALIZED/LOW-PREDICTABILITY BOUNDARY OR  
STORM-SCALE PROCESSES DOMINATE MESOSCALE TO SUBSYNOPTIC FORCINGS.  
AS SUCH...OVERALL SVR POTENTIAL REMAINS TOO ISOLATED/CONDITIONAL FOR  
MORE THAN MRGL PROBABILITIES.  
   
..OZARKS AND VICINITY
 
 
LACK OF BOUNDARY-LAYER LIFT ALONG/AHEAD OF WEAKENING FRONT FARTHER S  
LIKELY ACCOUNTS FOR DEARTH OF CONVECTION IN MOST PROGS FROM CENTRAL  
MO THROUGH OZARKS TO ERN OK/WRN AR. PRIND CONVECTIVE COVERAGE/  
INTENSITY WILL BE TOO LOW TODAY TO MAINTAIN EVEN MRGL SVR  
PROBABILITIES.  
   
..COASTAL CAROLINAS -- T.D. 2
 
 
LATEST NHC GUIDANCE BRINGS CENTER OF CIRCULATION CLOSE TO COAST AS  
MRGL TROPICAL STORM AFTER END OF PERIOD...BUT WITH INCREASE IN BOTH  
CONVECTION AND LOW-LEVEL SHEAR POSSIBLE OVERNIGHT AROUND NRN  
PERIPHERY OF CIRCULATION...OVER EXTREME ERN SC AND SRN NC COASTS.  
ATTM...FCST WIND FIELDS APPEAR TOO WEAK FOR UNCONDITIONAL TORNADO  
PROBABILITIES...WITH CURVED BUT RATHER SMALL LOW-LEVEL HODOGRAPHS  
AND 0-1 KM SRH BELOW 100 J/KG IN FCST SOUNDINGS. 06-12Z TIME FRAME  
ALSO WILL REPRESENT NOCTURNAL MIN IN INLAND BUOYANCY. FOR NOW...  
GIVEN THOSE FACTORS...WILL HOLD OFF INTRODUCING MRGL TORNADO  
PROBABILITIES FOR LATE PERIOD AND CONTINUE TO MONITOR INSTABILITY/  
WIND TRENDS. SOME RISK MAY NEED TO BE INTRODUCED FOR SMALL SEGMENT  
OF COASTAL CAROLINAS FOR LATE TONIGHT IF WHAT NOW IS STILL T.D. 2  
BECOMES STRONGER AND/OR MORE EXPANSIVE THAN CURRENTLY FCST. SEE NHC  
BULLETINS UNDER WMO HEADER WTNT32 KNHC FOR LATEST GUIDANCE ON TRACK  
AND INTENSITY...AS WELL AS TROPICAL WATCHES AND WARNINGS FOR THIS  
SYSTEM.  
 
..EDWARDS/ROGERS.. 05/28/2016  
 

 
 
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