SPC AC 101300
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0800 AM CDT THU JUN 10 2010
VALID 101300Z - 111200Z
...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF NEB...NE CO...AND
NW KS...
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL HI PLNS ENE INTO
THE UPR MS VLY...
...SYNOPSIS...
PATTERN WILL FURTHER AMPLIFY THIS PERIOD AS PACIFIC NW TROUGH
DEEPENS SE INTO THE GRT BASIN...AND DOWNSTREAM RIDGE EXPANDS NE
ACROSS THE UPR MS VLY/UPR GRT LKS. AT THE SAME TIME...NE TX CLOSED
LOW EXPECTED TO CONTINUE SLOWLY NE INTO AR AS UPSTREAM DISTURBANCE
NOW OVER SONORA MOVES TOWARD THE TX BIG BEND.
AT THE SFC...LARGE...LOOSELY-ORGANIZED AREA OF LOW PRESSURE NOW OVER
THE HI PLNS SHOULD CONSOLIDATE INTO A MAIN CENTER OVER ERN CO BY
THIS EVE. THE LOW WILL EDGE E/NE INTO NRN KS TONIGHT/EARLY
FRI...AND BECOME ELONGATED ROUGHLY PARALLEL TO THE SWLY FLOW ALOFT.
DIFFUSE WARM FRONT EXTENDING E/SE FROM THE LOW WILL ADVANCE SLOWLY
NE ACROSS THE LWR MO VLY...WHILE A SHALLOW COOL FRONT EVOLVES NW OF
THE LOW TONIGHT/EARLY FRI.
...CNTRL HI PLNS INTO THE UPR MS VLY TODAY THROUGH EARLY FRI...
STRONGEST PORTION OF NEB BOWING MCS AND ASSOCIATED WAA STORMS SHOULD
CONTINUE GENERALLY ESE ACROSS THE REMAINDER OF THE STATE AND INTO
WRN IA THROUGH MID/LATE MORNING /REF WW 291/. THE SYSTEM SHOULD
SLOWLY WEAKEN...ALTHOUGH PERHAPS NOT AS FAST AS SOME NOCTURNAL
SYSTEMS GIVEN BREADTH OF LLJ AND TENDENCY FOR MOISTURE RETURN TO
KEEP PACE WITH ADVECTIVE COMPONENT OF MCS MOTION.
LATER TODAY AND TONIGHT...THE SVR THREAT WILL ONCE AGAIN FOCUS OVER
THE CNTRL HI PLNS...WHERE VERY MOIST AIR /PW 1.50-1.75 INCHES AND
SFC DEWPOINTS IN THE MID TO UPR 60S F/ WILL RESIDE N AND E OF QSTNRY
SFC LOW. WEAK UPSLOPE FLOW...EXISTING MOISTURE...AND SFC HEATING
SHOULD SUPPORT STRONG STORM DEVELOPMENT OVER THE NRN CO AND ERN WY
MOUNTAINS BY 20-21Z...BENEATH 40-50 KT SW MID LVL FLOW. THIS
ACTIVITY SHOULD QUICKLY EVOLVE INTO SUPERCELLS THAT MOVE/DEVELOP E
INTO THE INCREASINGLY STRONG/MOIST LOW LVL ELY FLOW N OF SFC
LOW...AIDED BY GLANCING INFLUENCE OF LOW AMPLITUDE DISTURBANCE NOW
APPARENT IN WV IMAGERY NEARING KSLC.
GIVEN THE DISCRETE NATURE OF THE STORMS...DEEP EML...AND RICH
MOISTURE...THIS ACTIVITY LIKELY WILL PRODUCE VERY LARGE HAIL.
AND...GIVEN CONSIDERABLE LOW LVL DIRECTIONAL SHEAR...TORNADOES ALSO
APPEAR LIKELY...WITH PERHAPS A STRONG ONE AFTER DARK. ATTM...THIS
THREAT APPEARS MOST LIKELY FROM FAR NE CO /INVOF THE CHEYENNE RIDGE/
E INTO SRN PARTS OF THE NEB PANHANDLE/SW NEB...WHERE COMBINATION OF
MOST FAVORABLE STORM MODE AND THERMODYNAMIC/WIND ENVIRONMENT SHOULD
EXIST.
THE TSTMS SHOULD CONTINUE TO STRENGTHEN AND INCREASE IN NUMBER THIS
EVE AS THEY MOVE/DEVELOP E OR ENE INTO NOCTURNALLY-STRENGTHENED
40-50 KT LLJ. THIS SHOULD LEAD TO THE DEVELOPMENT OF ANOTHER
OVERNIGHT MCS. EMBEDDED SUPERCELLS AND BOWING STRUCTURES WILL
EXTEND THE SVR THREAT ENE ACROSS THE NWRN HALF OF NEB...SE
SD...AND...BY EARLY FRI...SRN MN.
...SW KS TO SW TX LATE AFTN/EARLY EVE...
FARTHER S...STRONG HEATING AND WEAK UPLIFT ALONG LEE TROUGH/ DRYLINE
MAY SUPPORT WDLY SCTD TSTM DEVELOPMENT BY 22Z OVER THE SRN HALF OF
THE HI PLNS...DESPITE STOUT EML. POTENTIAL FOR DEVELOPMENT MAY BE
ENHANCED BY TERRAIN CIRCULATIONS NEAR THE MEXICAN BORDER. STRONG
INSTABILITY /SBCAPE UP TO 4000 J PER KG/ WILL BE PRESENT. ALTHOUGH
DEEP SHEAR WILL DECREASE WITH SWD EXTENT...MID LVL FLOW WILL
INCREASE TO AT LEAST 20-25 KTS AS FAR S AS THE NRN TX PANHANDLE AS
THE WRN U.S. TROUGH EDGES EWD. THIS SETUP SHOULD FAVOR SLOWLY-MOVING
MULTICELLS AND SUPERCELLS WITH A THREAT FOR LARGE HAIL AND LOCALLY
DMGG WINDS. MOST OF THIS ACTIVITY SHOULD DIMINISH AFTER SUNSET.
...FAR E TX INTO LWR MS VLY...
SLOWLY NEWD MOVEMENT OF TX UPR LOW...AND SFC HEATING...SHOULD ONCE
AGAIN SUPPORT A DIURNAL BLOSSOMING OF SFC-BASED STORMS E AND NE OF
THE LOW. CONTINUING PRESENCE OF RICH BOUNDARY LAYER MOISTURE...HIGH
PW...AND MODEST SWLY MID LVL FLOW...TOGETHER SUGGEST THAT STORMS
COULD ASSUME WEAK ORGANIZATION INTO BANDS. SMALL AMPLITUDE BOWS IN
THIS ACTIVITY COULD YIELD LOCALLY DMGG WIND...MAINLY THIS AFTN WHEN
STORM COVERAGE WILL BE GREATEST.
..CORFIDI/STOPPKOTTE.. 06/10/2010
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
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