[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 131952
SWODY1
SPC AC 131950

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0250 PM CDT SUN AUG 13 2006

VALID 132000Z - 141200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE UPPER MS
VLY SWWD INTO THE CNTRL PLAINS...

...UPPER MS VLY SWD INTO THE CNTRL PLAINS...
19Z SFC ANALYSIS PLACES A TROUGH FROM CNTRL IA SWWD TO A HEAT LOW
VCNTY KTOP THEN SWWD INTO WRN KS.  A 1010 MB LOW WAS SITUATED VCNTY
KFSD WITH A N-S COLD FRONT FROM NCNTRL MN SWWD THROUGH THE LOW TO
ECNTRL CO.  BOUNDARY LAYER HEATING HAS BEEN STRONGEST AHEAD OF THE
PRE-FRONTAL TROUGH FROM SCNTRL IA SWWD ACROSS NWRN MO INTO KS WHERE
TEMPERATURES HAVE RISEN TO AOA 90 DEG F AND DEW POINTS HAVE REMAINED
 70-75 DEG F.

MAJORITY OF THE LARGE SCALE FORCING FOR ASCENT ASSOCD WITH THE UPPER
TROUGH WAS PASSING WELL N OF THE MOST UNSTABLE WARM SECTOR.  THUS...
TSTMS WILL BE DRIVEN MOSTLY BY THERMODYNAMIC PROCESSES.  THIS SHOULD
CONFINE THE MOST VIGOROUS TSTM DEVELOPMENT ALONG THE SERN EDGE OF
CURRENT CONVECTION...NAMELY FROM SCNTRL IA SWWD INTO EXTREME SERN
NEB...NWRN MO AND NRN/CNTRL KS.  BULK SHEAR WAS GENERALLY 35-40 KTS
IN THIS REGION AND MID-LEVEL LAPSE RATES BLO 6 DEG C/KM.  BUT...
GIVEN PRESENCE OF A HOT AND MOIST BOUNDARY LAYER AND GENERALLY
UNIDIRECTIONAL WSWLY FLOW ALOFT...STORMS WILL LIKELY DEVELOP INTO
SHORT LINE SEGMENTS GIVING DAMAGING WINDS. FURTHERMORE...A BRIEF
ISOLD TORNADO MAY OCCUR...MAINLY ACROSS EXTREME SCNTRL IA/NCNTRL MO
WHERE OUTFLOW BOUNDARY INTERSECTIONS MAY AUGMENT LOW-LEVEL HELICITY.
 ACTIVITY SHOULD MOVE ENEWD INTO/ACROSS THE UPPER MS VLY AND PARTS
OF NRN MO OVERNIGHT...BUT LIKELY WEAKEN AS BUOYANCY DECREASES WITH
ONSET OF NOCTURNAL COOLING.

A FEW TSTMS MAY DEVELOP VCNTY THE SFC LOW/COLD FRONT ACROSS SERN SD
INTO SWRN MN AND SWD ACROSS NWRN IA...NERN NEB LATER THIS AFTN. 
THIS REGION HAS HAD SOME AIR MASS RECOVERY COINCIDENT WITH MASS
CONVERGENCE.  OTHER THAN ISOLD HAIL/GUSTY WINDS...NO WIDESPREAD SVR
TSTMS ARE EXPECTED HERE.

FARTHER N...CLOUDS/POOR LAPSE RATE ENVIRONMENT WILL BE NEGATIVE
FACTORS FOR SUSTAINED DEEP MOIST CONVECTION FROM MN/WI NWD INTO THE
GRTLKS REGION.

..RACY.. 08/13/2006