SPC AC 160722
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0222 AM CDT THU APR 16 2009
VALID 181200Z - 191200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
SLOW MOVING NATURE TO UPPER LOW WILL RESULT IN FURTHER COMPLEXITY
DURING THE DAY3 PERIOD AS SIGNIFICANT THUNDERSTORM CLUSTERS WILL
OVERTURN AN OTHERWISE RECOVERING AIRMASS ACROSS THE SRN/CNTRL
PLAINS/LOWER MS VALLEY. IN THE ABSENCE OF STRONG SYNOPTIC SCALE
INFLOW/LLJ IT APPEARS INTENSITY OF THUNDERSTORM ACTIVITY WILL BE
MODULATED MORE AT THE LOCAL LEVEL...DESPITE THE MODEST MID-HIGH
LEVEL FLOW AND RELATIVELY STRONG DEEP LAYER SHEAR. LATEST THINKING
IS THERE WILL BE TWO PRIMARY AREAS FOR CONCENTRATED DEEP CONVECTION.
THE FIRST AREA OF CONCERN...AND POTENTIALLY MORE CONCENTRATED AND
PREDICTABLE...WILL BE BENEATH THE RESIDUAL UPPER LOW WHERE H5
TEMPERATURES WILL BE ON THE ORDER OF -20C. VERY COLD PROFILES AND
STEEP LAPSE RATES SHOULD RESULT IN MORE THAN ADEQUATE BUOYANCY FOR
THUNDERSTORM DEVELOPMENT ACROSS MUCH OF KS INTO CNTRL OK. IT/S NOT
ENTIRELY CLEAR HOW MUCH LOW LEVEL MOISTURE WILL REMAIN ACROSS THIS
REGION IN THE WAKE OF EARLIER MCS ACTIVITY...FOR THIS REASON WILL
NOT ISSUE A SLIGHT RISK AT THIS TIME. HOWEVER IF SFC DEW POINTS CAN
HOLD IN THE 50S THEN SIGNIFICANT INSTABILITY WOULD SUPPORT AT LEAST
HAIL BENEATH UPPER LOW.
FARTHER SOUTH...MODELS SUGGEST CONSIDERABLE AMOUNT OF THUNDERSTORM
ACTIVITY WILL EVOLVE ALONG AN AXIS FROM SCNTRL TX INTO AR/LA.
FORECAST SOUNDINGS SUGGEST LAPSE RATES WILL REMAIN RATHER WEAK AND
THIS SHOULD LIMIT DESTABILIZATION BENEATH AN OTHERWISE FAVORABLE
ZONE FOR ORGANIZED SEVERE DEVELOPMENT. ADDITIONALLY...LLJ IS NOT
FORECAST TO BE THAT STRONG WHICH MAY RESULT IN MULTIPLE THUNDERSTORM
CLUSTERS AND EXTENSIVE CLOUDINESS. UNTIL IT BECOMES CLEAR THIS
REGION WILL BE MORE UNSTABLE WILL OPT FOR LOW PROBABILITIES FOR
GUSTY WINDS/ISOLATED TORNADOES.
..DARROW.. 04/16/2009
CLICK TO GET WUUS03 PTSDY3 PRODUCT
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z
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