MESOSCALE DISCUSSION 0537
NWS STORM PREDICTION CENTER NORMAN OK
1047 AM CDT THU APR 03 2008
AREAS AFFECTED...N-CNTRL/NERN TX INTO S-CNTRL/SERN OK
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 031547Z - 031645Z
TSTMS /INITIALLY ELEVATED/ MAY INCREASE IN COVERAGE AND INTENSITY
LATE THIS MORNING INTO AFTERNOON. INITIALLY LARGE HAIL WOULD BE THE
PRIMARY HAZARD. BUT AS STORMS BECOME MORE SURFACE-BASED...AN
ATTENDANT THREAT OF TORNADOES AND DAMAGING WINDS WILL CONCURRENTLY
INCREASE. THERE IS STILL SOME UNCERTAINTY AS TO WHETHER DEVELOPING
STORMS WILL BECOME SUSTAINED...NECESSITATING A WW THIS MORNING. IT
DOES APPEAR THAT A WW WILL LIKELY BE REQUIRED AT SOME POINT LATER
TODAY.
VISIBLE SATELLITE AND REGIONAL RADAR IMAGERY INDICATE DEEPENING
CUMULUS CONVECTION/EARLY TSTM DEVELOPMENT FROM THE METROPLEX WSWWD
TO NEAR ABI...PERHAPS IN RESPONSE TO A LOW AMPLITUDE PERTURBATION
MOVING ACROSS THE REGION. LATEST MESOANALYSIS INDICATES THAT THIS
ACTIVITY IS OCCURRING WITHIN SYSTEM WARM SECTOR WHICH IS DELINEATED
BY A RAPIDLY RETREATING WARM FRONT WHICH EXTENDED FROM JUST N OF THE
RED RIVER NW OF SPS TO JUST SW OF PRX AS OF 15Z. HOWEVER...BASED ON
THE 12Z OBSERVED SOUNDING FROM FWD AND RUC PROXIMITY SOUNDINGS IT
APPEARS THAT THE DEVELOPING STORMS MAY STILL BE SLIGHTLY ELEVATED
ABOVE A NEAR SURFACE STABLE LAYER.
GIVEN THE MOISTENING LOW-LEVELS AND PRESENCE OF VERY STEEP MIDLEVEL
LAPSE RATES OF AROUND 8.5 C/KM...ENVIRONMENT IS ALREADY MODERATELY
TO STRONGLY UNSTABLE FOR ELEVATED PARCELS WITH MUCAPES OF 2000-3000
J/KG. SHOULD TSTMS BECOME SUSTAINED...THE INITIAL SEVERE THREAT
WILL BE LARGE HAIL. WITH TIME THE BOUNDARY LAYER SHOULD WARM
SUFFICIENTLY SUCH THAT ANY ONGOING ACTIVITY WILL BECOME
PROGRESSIVELY MORE SURFACE-BASED. GIVEN 45-55 KT OF EFFECTIVE BULK
SHEARS AND MODERATELY STRONG LOW-LEVEL SHEAR...THE POTENTIAL WILL
EXIST FOR SUPERCELLS CAPABLE OF TORNADOES...DAMAGING WINDS IN
ADDITION TO THE LARGE HAIL.
..MEAD.. 04/03/2008
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment