SPC AC 140625
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1225 AM CST FRI JAN 14 2011
VALID 151200Z - 161200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
SYNOPTIC PATTERN WILL UNDERGO LITTLE CHANGE SATURDAY WITH A BROAD
LOW AMPLITUDE TROUGH PERSISTING OVER THE ERN HALF OF THE COUNTRY AND
A CORRESPONDING UPSTREAM RIDGE OVER THE WRN STATES. PRIMARY FEATURE
OF INTEREST WILL BE THE SHORTWAVE TROUGH CURRENTLY MOVING THROUGH
THE GREAT BASIN. THIS FEATURE WILL ADVANCE SEWD INTO NRN MEXICO BY
EARLY SATURDAY...DECELERATING AS IT BECOMES CUTOFF FROM THE NRN
STREAM...THEN CONTINUE INTO S TX BY THE END OF THE PERIOD. MODELS
DIFFER SLIGHTLY ON TIMING OF THIS FEATURE.
...S TX...
ELY LOW-LEVEL TRAJECTORIES EMANATING FROM CP HIGH PRESSURE OVER THE
SERN STATES WILL PERSIST OVER THE WRN GULF SATURDAY. THIS WILL
SIGNIFICANTLY SLOW THE MODIFICATION OF THE GULF BOUNDARY LAYER AND
MAINTAIN STABLE AIR AT THE SURFACE. NEVERTHELESS...ESTABLISHMENT OF
A LEE TROUGH AND SLY LLJ WILL CONTRIBUTE TO PARTIALLY MODIFIED GULF
AIR ADVECTING NWD ABOVE THE STABLE LAYER AND BENEATH STEEPER LAPSE
RATES ACCOMPANYING THE SHORTWAVE TROUGH. THIS PROCESS WILL RESULT IN
MARGINAL ELEVATED INSTABILITY OVER S TX SATURDAY NIGHT. INITIALLY
SHALLOW CONVECTION WILL LIKELY DEVELOP WITHIN THE ZONE OF PERSISTENT
WARM ADVECTION AND ISENTROPIC LIFT. A FEW THUNDERSTORMS WILL BECOME
INCREASINGLY LIKELY AS DEEPER ASCENT INCREASES AND LAPSE RATES
STEEPEN WITH APPROACH OF THE SHORTWAVE TROUGH. THE THERMODYNAMIC
ENVIRONMENT AND EFFECTIVE SHEAR ARE EXPECTED TO REMAIN TOO MARGINAL
FOR ANY SEVERE THREAT.
...PACIFIC NW THROUGH NRN ROCKIES...
OTHER CONVECTION WILL ACCOMPANY IMPULSE EMBEDDED WITHIN LARGE SCALE
UPPER RIDGE AND DROPPING SEWD THROUGH THE PACIFIC NW AND NRN
ROCKIES...BUT ANY LIGHTNING COVERAGE IS EXPECTED TO REMAIN LESS THAN
10% DUE TO WEAK INSTABILITY.
..DIAL.. 01/14/2011
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z
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