SPC AC 111711
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1211 PM CDT SAT OCT 11 2008
VALID 121200Z - 131200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN AND
CNTRL HIGH PLAINS...
...SRN AND CNTRL HIGH PLAINS...
A STRONG UPPER-LEVEL LOW OVER THE INTERMOUNTAIN WEST IS FORECAST IS
TO LIFT QUICKLY NEWD TONIGHT AND INTO THE NRN HIGH PLAINS SUNDAY. A
LARGE UPPER-LEVEL TROUGH ASSOCIATED WITH THE SYSTEM SHOULD REMAIN
NEARLY STATIONARY WITH A LONG FETCH OF SOUTHWEST FLOW IN PLACE FROM
THE SRN ROCKIES INTO THE SRN AND CNTRL HIGH PLAINS. AT THE SFC...A
LOW SHOULD BE LOCATED IN ERN CO BY MIDDAY SUNDAY WITH A PACIFIC COLD
FRONT EXTENDING SWD ACROSS THE SRN ROCKIES. SCATTERED CONVECTION
MOSTLY ELEVATED IN NATURE IS FORECAST BY THE MODELS TO BE ONGOING
ALONG OR AHEAD OF THE BOUNDARY EARLY IN THE PERIOD DUE TO LIFT
ASSOCIATED WITH THE LOW-LEVEL JET AND LARGE-SCALE ASCENT AHEAD OF A
SUBTLE SHORTWAVE. DAYTIME SFC HEATING AND DESTABILIZATION SHOULD
ALLOW FOR SFC-BASED THUNDERSTORM DEVELOPMENT DURING THE AFTERNOON
ESPECIALLY ACROSS ERN NM AND WEST TX WHERE SFC DEWPOINTS MAY REACH
THE LOWER 60S F AND THE MOIST LAYER IS FORECAST TO EXTEND TO ABOUT
700 MB.
CONCERNING THE SEVERE POTENTIAL...A POWERFUL 90 TO 110 KT MID-LEVEL
JET IS FORECAST TO EJECT OUT OF THE BASE OF THE TROUGH INTO THE
CNTRL ROCKIES DURING THE DAY ON SUNDAY. THE ERN PART OF THIS JET
SHOULD INFLUENCE THE SLIGHT RISK AREA CREATING MODERATE TO STRONG
VERTICAL SHEAR PROFILES WITH 0-6 KM SHEAR VALUES REACHING 45 TO 55
KT. THIS ALONG WITH ALONG WITH A GRADUALLY VEERING WINDS WITH HEIGHT
BELOW 700 MB EVIDENT ON FORECAST SOUNDINGS SHOULD PROVIDE SUPPORT
FOR ROTATING STORMS. DUE TO THE RATHER WEAK INSTABILITY
FORECAST...THE SEVERE THREAT WILL LIKELY REMAIN ISOLATED ACROSS THE
SLIGHT RISK AREA. THE AMOUNT OF LOW-LEVEL SHEAR COULD RESULT IN A
TORNADO WITH ANY DOMINANT SUPERCELL THAT CAN PERSIST DURING MAX
HEATING. ANY ROTATING STORM WOULD LIKELY HAVE A THREAT FOR WIND
DAMAGE AND/OR A LOW-END THREAT FOR HAIL. THE WIND DAMAGE POTENTIAL
WOULD LIKELY BE MORE LIMITED ACROSS THE NRN PART OF THE SLIGHT RISK
AREA WHERE STORMS ARE LESS LIKELY TO BE SFC-BASED.
..BROYLES.. 10/11/2008
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0600Z
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