Day 1 Convective Outlook – Overall

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0239 PM CDT MON APR 07 2008

VALID 072000Z – 081200Z

…THERE IS A MDT RISK OF SVR TSTMS ACROSS A PORTION OF SWRN/SCNTRL
OK AND WRN NORTH TX…

…THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF THE CNTRL/SRN
PLAINS…

….CNTRL/SRN PLAINS…
19Z SFC ANALYSIS PLACES A WEAK SFC LOW OVER THE ERN TX PNHDL WITH A
WARM FRONT DEVELOPING NWD INTO CNTRL OK. A DRYLINE EXTENDS S FROM
THE LOW INTO WRN NORTH TX AND THE ERN LOW ROLLING PLAINS. AHEAD OF
THE DRYLINE…NEAR 60F DEW POINTS HAD ADVECTED NWD INTO CNTRL/SRN OK
BENEATH AROUND 8 DEG C/KM MID-LVL LAPSE RATES. GIVEN RAPIDLY
WARMING TEMPERATURES…MLCAPES WERE APPROACHING 2000 J/KG WITH
WEAKENING INHIBITION.

CONTINUED WARMING INTO THE UPR 70S/NEAR 80F AND APPROACH OF A LARGER
SCALE MID-LVL WAVE OVER THE SRN HIGH PLAINS WILL LIKELY RESULT IN
SUSTAINED TSTM INITIATION ALONG/E OF THE DRYLINE FROM SWRN OK SWD
INTO WRN N TX/BIG COUNTRY BY 21Z. EFFECTIVE BULK SHEAR AROUND 50
KTS AND MAGNITUDE OF LAPSE RATES/INSTABILITY SUGGEST THAT SUPERCELLS
WILL BE POSSIBLE WITH VERY LARGE HAIL. MOREOVER…TORNADO
PROBABILITIES WILL BECOME MAXIMIZED EARLY THIS EVENING OVER
SWRN…CNTRL…SCNTRL OK AND WRN NORTH TX WHERE BOUNDARY LAYER WINDS
REMAIN BACKED /SRH 250+ M2/S2/ IN A REGION WITH A RELATIVELY MOIST
BOUNDARY LAYER. LATEST TORNADO PROBABILITIES HAVE INCLUDED A
SIGNIFICANT TORNADO RISK OVER THE MDT RISK AREA ALONG WITH AN
UPGRADE TO VERY LARGE HAIL PROBABILITIES. GIVEN A MERE 5 DEG F
INCREASE IN THE SFC DEW POINTS WOULD BOOST THE CONFIDENCE LEVEL FOR
MORE ROBUST TORNADO PROBABILITIES…BUT THIS LEVEL OF CONFIDENCE IS
LACKING ATTM. ACTIVITY WILL MOVE ENEWD INTO PORTION OF ERN OK
OVERNIGHT WITH A CONTINUED RISK FOR LARGE HAIL…DMGG WIND GUSTS AND
ISOLD TORNADOES.

FARTHER N…TSTMS WILL CONTINUE TO FORM N OF THE WARM FRONT
THROUGHOUT SRN KS. STEEP MID-LEVEL LAPSE RATES AND STRONG EFFECTIVE
SHEAR WILL FOSTER HAIL PRODUCTION IN ANY STRONGER STORMS.

…ERN LWR MI…
OCCLUDED FRONT ASSOCD WITH A STRONG MID-LEVEL IMPULSE CONTINUES TO
RAPIDLY SHIFT EWD ACROSS THE CNTRL GRTLKS REGION AT MID-AFTN. AHEAD
OF THE FRONT…SFC TEMPS HAVE RISEN WELL INTO THE 50S/60S WITH MID
40 DEW POINTS COMMON… CONTRIBUTING TO A FEW HUNDRED J/KG SBCAPE.
ISOLD-WDLY SCT TSTMS WILL BE POSSIBLE BEFORE THE FRONT CLEARS ERN
LWR MI BY 00Z. ACTIVITY MAY YIELD ISOLD DMGG WIND GUSTS OR
HAIL…BUT WIDESPREAD SVR TSTMS ARE NOT ANTICIPATED.

..RACY.. 04/07/2008