SPC AC 061703
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1203 PM CDT FRI OCT 06 2006
VALID 071200Z - 081200Z
...THERE IS A SLGT RISK OF SVR TSTMS SAT AFTN ACROSS PARTS OF THE
SRN PLATEAU....
STRONG SHORT WAVE TROUGH EMBEDDED WITHIN BROADER SCALE WESTERN U.S.
UPPER TROUGH IS BEGINNING TO ACCELERATE NORTHEASTWARD THROUGH THE
SOUTHERN CALIFORNIA/LOWER COLORADO VALLEY REGION. SYSTEM IS PROGGED
TO REACH THE NORTH CENTRAL ROCKIES EARLY SATURDAY...AS A STRONG
NORTHERN BRANCH SHORT WAVE PROGRESSES EAST OF THE CANADIAN ROCKIES.
MODELS SUGGEST BOTH FEATURES WILL MERGE NEAR THE CENTRAL
CANADIAN/U.S. BORDER LATER SATURDAY/SATURDAY NIGHT...WITH ASSOCIATED
FORCING CONTRIBUTING TO LOW/MID-LEVEL CYCLOGENESIS ACROSS THE
NORTHERN PLAINS INTO WESTERN ONTARIO BY 12Z SUNDAY.
IN THE WAKE OF THE PRIMARY IMPULSE...MODELS INDICATE A SERIES OF
WEAKER PERTURBATIONS WILL CONTINUE TO DIG OUT OF THE EASTERN
PACIFIC...MAINTAINING UPPER TROUGHING AND A BROAD MID-LEVEL
CIRCULATION OVER THE SOUTHWESTERN STATES. A BELT OF MODERATELY
STRONG SOUTHWESTERLY FLOW WILL PERSIST AHEAD OF UPPER TROUGH...AND
TO THE WEST OF WEAKENING CENTRAL STATES RIDGING...ACROSS THE
SOUTHERN PLATEAU THROUGH THE NORTHERN PLAINS. THIS WILL CONTINUE TO
AID A NORTHWARD TRANSPORT OF MOISTURE OFF THE LOWER LATITUDE EASTERN
PACIFIC.
ACROSS THE EAST...VARIABILITY EXISTS AMONG THE MODELS CONCERNING THE
EVOLUTION OF A CLOSED LOW...WHICH WILL BECOME INCREASINGLY CUT-OFF
FROM THE STRONGER WESTERLIES. BUT...MODELS SUGGEST SYSTEM WILL
GENERALLY DIG SOUTHWARD ALONG SOUTH ATLANTIC COASTAL AREAS... WITH
ANY SIGNIFICANT CONVECTIVE POTENTIAL LIKELY NEAR ASSOCIATED FRONTAL
ZONE OFFSHORE.
...SOUTHERN PLATEAU/SOUTHERN ROCKIES...
CONVECTIVELY UNSTABLE ENVIRONMENT NOW DEVELOPING ALONG THE WESTERN
FRINGE OF MID/UPPER MOISTURE PLUME IS EXPECTED TO PERSIST INTO
SATURDAY...FROM CENTRAL/EASTERN ARIZONA INTO PORTIONS OF THE
CENTRAL/SOUTHERN ROCKIES. AND..WEAK MID-LEVEL INHIBITION SHOULD
ALLOW FOR THE DEVELOPMENT OF SCATTERED THUNDERSTORMS WITH DAYTIME
HEATING. MODELS SUGGEST FLOW REGIME WILL REMAIN SUFFICIENTLY STRONG
AND SHEARED FOR UPDRAFT ROTATION IN STRONGER/LONGER-LIVED
CONVECTION. ISOLATED SUPERCELLS WITH ASSOCIATED SEVERE THREATS
APPEAR POSSIBLE...ESPECIALLY ACROSS THE LOWER DESERTS OF CENTRAL
ARIZONA...WHERE MIXED LAYER CAPE MAY EXCEED 1000 J/KG BY PEAK
AFTERNOON HEATING.
...NORTHERN/CENTRAL PLAINS...
CONVECTIVE DEVELOPMENT APPEARS POSSIBLE NEAR DEEPENING SURFACE LOW
ACROSS NORTH DAKOTA SATURDAY AFTERNOON AND EVENING...AND ALONG/
AHEAD OF TRAILING SURFACE FRONT ADVANCING EASTWARD THROUGH THE
NORTHERN/CENTRAL PLAINS SATURDAY NIGHT. HOWEVER...DUE PRIMARILY TO
LIMITED MOISTURE AVAILABILITY...IT APPEARS AT THE PRESENT TIME THAT
ACTIVITY WILL REMAIN SPARSE IN COVERAGE WITH SEVERE POTENTIAL
REMOTE.
..KERR.. 10/06/2006
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0800Z
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