SWODY1
SPC AC 151604
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
ISSUED BY 15TH OWS SCOTT AIR FORCE BASE IL
1104 AM CDT THU MAR 15 2012
VALID 151630Z - 161200Z
...THERE IS A SLGT RISK OF SVR TSTMS OZARKS TO OH/TN VALLEYS AND ERN
GREAT LAKES...
...SYNOPSIS...
RELATIVELY WEAK SWLY MID LEVEL FLOW EXISTS OVER MUCH OF THE U.S.
THIS MORNING WITH STRONGER WINDS ALOFT CONFINED TO THE NORTHWEST/NRN
PLAINS AND NRN NEW ENGLAND. ELSEWHERE...A BROAD BELT OF 10-30KT
500MB FLOW EXTENDS FROM THE SOUTHWEST TO THE OH VALLEY ATOP SLIGHTLY
STRONGER LOW LEVEL SWLY FLOW ON THE WRN FLANK OF ANTICYCLONE
ANCHORED OVER THE SOUTHEAST AND ADJACENT ATLANTIC. MOST PRONOUNCED
HEIGHT FALLS THIS PERIOD WILL OCCUR IN ASSOCIATION WITH A PACIFIC
TROUGH SPREADING INLAND ACROSS WA/ORE. A LOW AMPLITUDE SHORT WAVE
TROUGH EMBEDDED WITHIN THE WEAK FLOW ACROSS THE PLAINS...IN TANDEM
WITH A SOMEWHAT STRONGER IMPULSE OVER CANADA...WILL RESULT IN WEAK
HEIGHT FALLS SPREADING EAST FROM SRN PLAINS TO THE OH VALLEY/GREAT
LAKES THROUGH TONIGHT.
...OZARKS TO OH/TN VALLEYS AND ERN GREAT LAKES...
ANOMALOUSLY HIGH PW/MOISTURE AND MEAGER MID LEVEL FLOW/SHEAR WILL
CONTINUE TO SUPPORT AN ATYPICAL SETUP FOR MID-MARCH TSTM DEVELOPMENT
ACROSS AREAS FROM THE OZARKS ACROSS THE MID/LOWER MS VALLEY TO THE
MIDWEST THROUGH TODAY. ONGOING STORMS FROM SRN IND TO OH/KY/WV AND
ERN TN ARE IN RESPONSE TO MASS CONVERGENCE AND ISENTROPIC LIFT ON
THE ERN EDGE OF EXTENSIVE CNTRL U.S. EML PLUME. RECENT TRENDS AND
UPWIND PROPAGATION VECTORS SUGGEST THE MCS ROOTED ABOVE THE BOUNDARY
LAYER IN OH/WV MAY PRODUCE LOCALLY HEAVY RAIN THIS MORNING. DESPITE
THE LACK OF STRONGER VERTICAL SHEAR OVER THE AREA BASED ON MORNING
SOUNDINGS AND OBJECTIVE ANALYSIS DATA SOME HAIL POTENTIAL WILL
PERSIST DUE TO STEEP LAPSE RATES AND LOW FREEZING LEVELS.
...ARKLATEX AREA...
CONTINUING TO MONITOR AREA FOR ISOLATED SEVERE POTENTIAL AS WEAK
SHORTWAVE AND WEAK SPEED MAX MOVES EASTWARD FROM NORTHERN TX. SHEAR
CONDITIONS REMAIN WEAK, HOWEVER ANALYSIS DATA AND SATELLITE INDICATE
AMPLE EXHAUST IN UPPER TROPOSPHERE WITH LOW LEVEL INSTABILITY
ALREADY PRESENT.
...ELSEWHERE...
THE AFOREMENTIONED WEAK CIRCULATION/DISTURBANCE SPREADING EAST
ACROSS THE SRN PLAINS THIS MORNING WILL BE ACCOMPANIED BY 10-30KT
MID LEVEL FLOW PER LATEST PROFILER AND VWP OBSERVATIONS. LIFT
ASSOCIATED WITH THIS IMPULSE WILL SPREAD EAST TOWARD THE MIDWEST AND
MS VALLEY ATOP THE BROAD LOW LEVEL WARM/MOIST CONVEYOR BELT. POCKETS
OF GREATER DIURNAL HEATING WILL CONTRIBUTE TO AREAS OF STRONG
DESTABILIZATION OVER THE CNTRL AND SRN U.S. THIS AFTERNOON. MODEL
GUIDANCE SUGGESTS THAT WEAKER INHIBITION EAST OF THE GREAT PLAINS
SHOULD BE OVERCOME/ELIMINATED THROUGH A COMBINATION OF BACKGROUND
ASCENT AND BOUNDARY LAYER DIABATIC HEATING/MIXING. MULTICELLULAR
TSTM DEVELOPMENT IS EXPECTED IN THIS REGIME AND DESPITE LACK OF
STRONGER DEEP-LAYER SHEAR THE THREAT FOR SCATTERED TO NUMEROUS HAIL
AND GUSTY WIND EVENTS SEEMS POSSIBLE INTO THIS EVENING. IF GREATER
STORM-SCALE ORGANIZATION CAN DEVELOP/EVOLVE THROUGH THE DAY IT MAY
BE POSSIBLE TO PROVIDE A MORE DETAILED/FOCUSED TSTM WIND THREAT AREA
BUT HAIL APPEARS TO BE THE PREDOMINANT SEVERE THREAT AT THIS TIME.
WEAK FRONT WILL AID LIFT AMIDST INCREASINGLY UNSTABLE AIRMASS ACROSS
LOWER MI AND OH LATER TODAY TO SUPPORT A FEW CLUSTERS/LINES OF
STORMS ALSO CAPABLE OF PRODUCING HAIL AND GUSTY WINDS.
..15_OWS.. 03/15/2012
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.
No comments:
Post a Comment