SPC AC 151233
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0733 AM CDT SUN OCT 15 2006
VALID 151300Z - 161200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER SERN NM AND SWRN TX...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE
MIDDLE/UPPER TX AND SWRN LA COAST...
...SERN NM/SWRN TX...
MID LEVEL LAPSE RATES WILL STEEPEN AS STRONG ASCENT SPREADS FROM
WEST TO EAST ACROSS THIS REGION TODAY AHEAD OF APPROACHING UPPER
LOW. STORMS EARLY THIS MORNING HAVE ALREADY ORGANIZED INTO SMALL
SUPERCELLS...INDICATING 500-1000 J/KG MUCAPE IS MORE THAN ADEQUATE
FOR INTENSE/ORGANIZED STORMS GIVEN VERY STRONG DEEP LAYER SHEAR.
FORECAST SOUNDINGS SUGGEST STORMS THIS MORNING REMAIN SLIGHTLY
ELEVATED ABOVE A STABLE SURFACE LAYER...THOUGH LONGER-LIVED STORMS
WILL BE CAPABLE OF MARGINALLY SEVERE HAIL AND ISOLATED
STRONG/DAMAGING WINDS.
EXPECT LACK OF MID/HIGH LEVEL CLOUDS WILL ALLOW SOME MIXING TO OCCUR
OVER HIGHER TERRAIN OF FAR SWRN TX/SRN NM/NRN CHIHUAHUA TO THE SOUTH
OF SURFACE FRONT NOW EXTENDING FROM W-CENTRAL TX SWWD INTO SWRN NM.
WHERE POCKETS OF HEATING CAN OCCUR....MLCAPE FROM 500-1000 J/KG
COULD DEVELOP ALONG NWRN EXTENT OF LOWER 60F SURFACE DEW POINT AXIS
EXTENDING INTO SWRN TX/FAR SERN NM THIS AFTERNOON. EFFECTIVE SHEAR
NEAR 50 KT WILL BE SUFFICIENT FOR A FEW SURFACE-BASED
SUPERCELLS/ORGANIZED CLUSTERS THIS AFTERNOON AND EVENING. IF
SUFFICIENT MLCAPE CAN DEVELOP...LARGE HAIL WILL BE PRIMARY SEVERE
THREAT ALONG WITH ISOLATED DAMAGING WINDS.
...MIDDLE/UPPER TX COAST INTO SWRN LA...
RICH TROPICAL MOISTURE CONTINUES TO LIFT NWD ACROSS THE WRN GULF OF
MEXICO THIS MORNING WITH PW/S IN EXCESS OF 2 INCHES AND SURFACE DEW
POINTS IN THE MID/UPPER 70S LIKELY SPREADING INTO THE UPPER TX/SWRN
LA COAST TODAY. THIS WILL OCCUR UNDER INCREASING SLY H85 FLOW AHEAD
OF APPROACHING MID/UPPER LOW NOW MOVING INTO THE SRN ROCKIES.
MODELS ARE CONSISTENT IN DEVELOPING 50+ KT LLJ INTO SERN TX BY
00Z...WHICH STRENGTHENS TO NEAR 70 KT OVERNIGHT ACCORDING TO THE
NAM/WRF.
THUNDERSTORMS WILL STEADILY INCREASE INTO THE MIDDLE/UPPER TX COAST
AND SWRN LA THROUGH THE DAY AND CONTINUE OVERNIGHT ALONG AND NORTH
OF MARITIME WARM FRONT NOW DEVELOPING ALONG AND JUST OFF THE UPPER
TX COAST. THOUGH DEEP MOIST PROFILES WILL LIMIT AVAILABLE
INSTABILITY....RICH LOW LEVEL MOISTURE AND TEMPERATURES APPROACHING
THE LOWER 80S SHOULD BE COMMON BEHIND THIS WARM FRONT. THIS IS
EXPECTED TO RESULT IN MARGINAL SURFACE-BASED INSTABILITY WITHIN
EXTREME LOW LEVEL SHEAR AND HIGH VALUES OF BOUNDARY LAYER RELATIVE
HUMIDITY. THIS WILL SUPPORT AN INCREASINGLY FAVORABLE ENVIRONMENT
FOR LOW LEVEL ROTATION WHERE POCKETS OF SURFACE-BASED CAPE CAN
MAXIMIZE...ESPECIALLY LATER TODAY AND TONIGHT UNDER STRENGTHENING
LLJ AXIS. FAST MOVING SMALL LINES AND SUPERCELLS ARE EXPECTED TO
DEVELOP DURING THIS PERIOD WITH ATTENDANT THREATS OF DAMAGING WINDS
AND ISOLATED TORNADOES.
..EVANS/GUYER.. 10/15/2006
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
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