DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0756 AM CDT SAT MAY 01 2010
VALID 011300Z - 021200Z
...THERE IS A HIGH RISK OF SVR TSTMS OVER PARTS OF AR...MS...TN AND
THE MO BOOTHEEL...
...THERE IS A MDT RISK OF SVR TSTMS SURROUNDING THE HIGH RISK AREA
OVER PARTS OF THE LWR MS...LWR TN AND LWR OH VLYS...
...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE ABOVE AREAS
FROM E TX NEWD INTO THE UPR OH VLY...
...SYNOPSIS...
HIGH AMPLITUDE CNTRL STATES TROUGH WILL MOVE ONLY SLOWLY E THIS
PERIOD AS ASSOCIATED NRN PLAINS UPR LOW REMAINS QSTNRY AND ATTENDANT
SHORTWAVE TROUGH NOW ENTERING CHIHUAHUA SHEARS ENE ACROSS W
TX...OK...AND...BY SUN MORNING...KS/MO. MID/UPR LVL
SPEED MAX WITH THE CHIHUAHUA SYSTEM WILL REDEVELOP NE INTO N TX/OK
BY THIS EVE...AND FURTHER EXPAND NE ACROSS MID MS VLY/UPR GRT LKS
EARLY SUN.
AT THE SFC...MAIN FRONTAL ZONE WILL REMAIN NEARLY STNRY FROM LWR MI
TO E TX TODAY...WITH COMPOSITE OUTFLOW BOUNDARY LEFT BY OVERNIGHT
STORMS LIKELY TO LIFT SLOWLY N ACROSS AR AND THE LWR TN VLY. A WAVE
SHOULD FORM OVER NE TX OR THE ARKLATEX LATER TODAY...NEAR
INTERSECTION OF OUTFLOW BOUNDARY WITH FRONT. THE WAVE SHOULD TRACK
NNE INTO THE LWR OH VLY TONIGHT/EARLY SUN.
...E TX/LWR MS VLY INTO THE LWR TN/LWR OH VLYS THROUGH TONIGHT...
WSW-ENE ORIENTED QLCS OVER THE LWR MS AND TN VLYS MAY FURTHER WEAKEN
LATER THIS MORNING AS WEAK HEIGHT RISES OVERSPREAD REGION AND SFC
TEMPERATURES REACH DIURNAL MINIMUMS. SFC HEATING AND CONTINUED
INFLOW OF VERY MOIST AIR SHOULD...HOWEVER...SUPPORT REDEVELOPMENT OF
SOME STORMS IN WHAT IS LEFT OF THE MCS BY EARLY AFTN...WITH
ADDITIONAL DEVELOPMENT POSSIBLE TO ITS S OVER SRN/CNTRL AR AND NRN
MS. OTHER STORMS MAY FORM LATER THIS MORNING AND THIS AFTN OVER NE
TX AND SE OK...AS ISENTROPIC ASCENT DOWNSTREAM FROM CHIHUAHUA UPR
IMPULSE INCREASES ATOP SHALLOW FRONT.
COMBINATION OF DAYTIME HEATING AND RICH MOISTURE /PW 1.50-1.75
INCHES WITH SFC DEWPOINTS IN THE LOW 70S/ SHOULD ALLOW FOR
SUBSTANTIAL LOW LVL DESTABILIZATION ALONG AND S OF MCS OUTFLOW
BOUNDARY AND E OF FRONT...WITH SBCAPE EXPECTED TO BE AOA 2000 J/KG
WITH MINIMAL CINH. COUPLED WITH STRONGLY-SHEARED LOW TO MID LVL
WIND FIELD...SETUP COULD SUPPORT SCTD SUSTAINED SUPERCELLS WITH
TORNADOES/SVR HAIL.
AS THE CHIHUAHUA SYSTEM AND ASSOCIATED MID/UPR LVL SPEED MAX /WITH
250 MB FLOW AROUND 150 KTS/ CONTINUE NEWD LATER THIS AFTN AND
TONIGHT...DOWNSTREAM SLY LLJ SHOULD MARKEDLY INCREASE OVER THE LWR
MS AN TN VLYS. THIS SHOULD SUPPORT ENHANCEMENT OF EXISTING
STORMS...AS WELL AS ADDITIONAL DEVELOPMENT...FROM THE ARKLATEX
E/NEWD INTO THE LWR TN AND LWR OH VLYS THROUGH THE
EVENING/OVERNIGHT.
60 KT DEEP SWLY SHEAR AND DEEPLY-MOIST ENVIRONMENT WITH NEARLY
UNIDIRECTIONAL MID/UPR LVL FLOW WILL BE FAVORABLE FOR SUPERCELL ECHO
TRAINING/LEWPS AS SFC WAVE TRACKS NE TOWARD THE OH VLY. THE SETUP
ULTIMATELY MAY SUPPORT MULTIPLE CORRIDORS HAVING A POTENTIAL FOR
STRONG TORNADOES FROM MUCH OF AR AND NRN MS NEWD INTO WRN/CNTRL
TN...WRN/CNTRL KY AND PERHAPS SRN IL/SRN INDIANA TONIGHT/EARLY SUN.
...MIDDLE/UPR OH VLY...
ERN END OF AFOREMENTIONED QLCS SHOULD CONTINUE E ACROSS ERN KY AND
CNTRL/ERN OH THROUGH LATER THIS MORNING. DIURNAL DESTABILIZATION
AND MODEST LOW LVL MOISTURE INFLOW MAY SUPPORT A MODEST SVR THREAT
/DMGG WINDS OR AN ISOLD TORNADO/ THROUGH EARLY EVE. ADDITIONAL
STRONG TO SVR ACTIVITY MAY AFFECT THE REGION LATE IN THE PERIOD
/AFTER 06Z SUN/ AS SFC WAVE MOVES NE TOWARD THE LWR OH VLY AND
ASSOCIATED LLJ STRENGTHENS OVER ERN KY/OH.
..CORFIDI/GARNER.. 05/01/2010
