ZCZC SPCSWODY1 ALL
ACUS01 KWNS 041950
SPC AC 041950

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0250 PM CDT MON AUG 04 2003

VALID 042000Z - 051200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 10 ENE
WMC 30 NNE SVE MHS 40 SW MFR 40 NW MFR 40 SE EUG RDM 10 E BNO 75 N
WMC 10 ENE WMC

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 20 NNE
ART 10 SE UCA 10 ESE CXY LYH 40 SSE AND 10 SE CSG 45 SW TCL 20 W GWO
40 SE PGO 25 S GAG 30 NNE CAO LHX LIC RAP 60 S Y22 20 SSW MBG 10 N
9V9 30 SW OFK FNB 30 NNW SZL 35 NW CGI 40 NW HOP 40 N SDF 20 WSW JXN
30 ESE MTC

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 35 WSW FHU 40 ESE INW
30 ESE U17 15 SW MLF 30 NW TPH 55 NE MER ACV ...CONT... ONP 20 NE
DLS 35 NE ALW 25 E S80 30 WNW MQM WEY 40 NNW COD BIL 40 E LWT 30 NNW
HVR ...CONT... 30 W RRT 25 NNE AXN 30 N DSM 35 NE COU BLV 10 ESE MTO
20 ESE MKE 30 SE CMX ...CONT... 25 SW BPT 50 N BPT 10 E TYR 40 E DAL
40 SSE SPS 60 S CDS 20 SSE INK 75 S MRF

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE PLAINS EWD ACROSS THE
TN VALLEY INTO THE LOWER GREAT LAKES...

...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF ORE/NRN CA AND
NWRN NV...

...SYNOPSIS...
CLOSED MID/UPPER-LEVEL LOW OVER THE SRN GREAT LAKES WILL SLOWLY
PROGRESS EWD THROUGH THE REMAINDER OF THE FORECAST PERIOD AS
SHORTWAVE TROUGH OVER THE CNTRL OH VALLEY ROTATES NEWD INTO THE
CNTRL APPALACHIANS. FARTHER W...SHORTWAVE TROUGHS OVER ERN MT/WRN ND
AND CNTRL NEB WILL TRANSLATE EWD/SEWD AROUND UPPER-LEVEL RIDGE WHICH
WILL REMAIN IN PLACE OVER THE SRN ROCKIES. OVER THE PACIFIC
NW...EARLY AFTERNOON WATER VAPOR IMAGERY SHOWS UPPER-LEVEL LOW
SLOWLY PROGRESSING EWD TOWARD THE NRN CA COAST.

IN THE LOW LEVELS...SURFACE FRONT ASSOCIATED WITH THE ERN CONUS
MID-LEVEL TROUGH CURRENTLY EXTENDS FROM WRN/CNTRL OH SWWD THROUGH
THE LOWER OH/MID MS VALLEY TO A LOW PRESSURE AREA OVER NWRN OK. THE
ERN END OF THIS FRONT WILL MOVE EWD/SEWD TONIGHT AHEAD OF SHORTWAVE
TROUGH OVER THE CNTRL OH VALLEY. A NNW-SSE BOUNDARY ALSO EXISTS
EARLY THIS AFTERNOON FROM EXTREME ERN MT/WRN ND SWD TO THE LOW OVER
NWRN OK.

...OH VALLEY AND LOWER GREAT LAKES...
DIABATIC HEATING AND SURFACE DEWPOINTS IN THE MID TO UPPER 60S
BENEATH MODESTLY COOL MID-LEVEL TEMPERATURES /-12 TO -13C AT 500MB/
HAVE CONTRIBUTED MLCAPES OF 500-1500 J/KG THIS AFTERNOON FROM THE
SRN GREAT LAKES INTO CNTRL OH VALLEY. DPVA JUST E OF MID-LEVEL
TROUGH AXIS AND LOW-LEVEL CONVERGENCE ALONG SURFACE BOUNDARY HAVE
ALLOWED TSTMS TO DEVELOP THIS AFTERNOON FROM MI SWD THROUGH IND/OH
AND CNTRL KY. ALTHOUGH REGIONAL VWP DATA INDICATE RELATIVELY WEAK
0-6KM SHEAR...STRONGER FLOW EXISTS ABOVE 8KM...ESPECIALLY ACROSS ERN
PARTS OF KY AND OH. THUS...IT APPEARS THAT SOME STORM ORGANIZATION
IS POSSIBLE THROUGH THE REMAINDER OF THE AFTERNOON AND EARLY THIS
EVENING. WBZ HEIGHTS OF 8.5 TO 9.5 KFT SUGGEST THE POTENTIAL FOR
LARGE HAIL WITH THE STRONGEST STORMS. CONVECTION SHOULD BEGIN TO
DIMINISH LATER THIS EVENING AS BOUNDARY LAYER COOLS AND STABILIZES.

...MIDDLE MS VALLEY INTO THE TN VALLEY...
REGIONAL PLAN VIEW VWP/PROFILER DATA SHOW MID/UPPER-LEVEL JET MAX
CURRENTLY OVER THE MID MS VALLEY DIVING SWD. AIR MASS BENEATH THESE
STRONGER WINDS CONTINUES TO DESTABILIZE THIS AFTERNOON WITH MLCAPES
NOW APPROACHING 1500-2500 J/KG. ONGOING ELEVATED TSTMS TO THE W OF
THE AREA OVER CNTRL KS/OK MAY BECOME SURFACED-BASED AS THEY BEGIN TO
MOVE EWD/SEWD INTO THE INSTABILITY AXIS. ADDITIONAL DEVELOPMENT IS
ALSO OCCURRING OVER SERN MO WHERE WSWLY 20KT LLJ IS FOCUSING
WAA/ISENTROPIC ASCENT OVER SURFACE BOUNDARY. GIVEN THE DEGREE OF
INSTABILITY AND SHEAR...ORGANIZED SEVERE TSTMS... INCLUDING A FEW
SUPERCELLS APPEAR LIKELY. DAMAGING WINDS AND LARGE HAIL WILL BE THE
PRIMARY SEVERE WEATHER THREATS WITH THESE STORMS.

TSTMS SHOULD INCREASE IN COVERAGE OVERNIGHT /POSSIBLY EVOLVING INTO
ONE OR MORE MCS/S/ ACROSS PORTIONS OF MO AND AR AS SWLY LLJ
STRENGTHENS TO 35-40KTS AHEAD OF SHORTWAVE TROUGH DIVING SEWD INTO
THE MID MS VALLEY. MOIST BOUNDARY-LAYER CONDITIONS /MODERATE
INSTABILITY/ AND MODESTLY STRONG MID-LEVEL FLOW ACROSS THIS AREA 
SHOULD SUSTAIN VIGOROUS CONVECTION WITH THE POTENTIAL FOR PRIMARILY
DAMAGING WINDS.

...NRN/CNTRL PLAINS...
FORCING FOR ASCENT AHEAD OF SHORTWAVE TROUGH OVER WRN ND AND
SLIGHTLY UNSTABLE AIR MASS FOR ELEVATED PARCELS ARE SUPPORTING
ONGOING CONVECTIVE DEVELOPMENT OVER ND ATTM. ALTHOUGH ISOLATED
MARGINALLY SEVERE HAIL REMAINS POSSIBLE WITH THE STRONGEST
CELLS...IT APPEARS THAT THE MINIMAL INSTABILITY WILL LIMIT OVERALL
SEVERE WEATHER POTENTIAL. FARTHER S...ACROSS WRN SD SWD INTO WRN
KS/ERN CO...STRONG HEATING AND DEWPOINTS IN THE 60S HAVE CONTRIBUTED
TO MLCAPES OF 1000-2000 J/KG TO THE E OF AFOREMENTIONED N-S
BOUNDARY. WATER VAPOR IMAGERY SUGGESTS THAT WEAK SYNOPTIC-SCALE
SUBSIDENCE IS OCCURRING ACROSS THIS INSTABILITY AXIS FROM WRN SD SWD
ACROSS WRN NEB. HOWEVER...FROM REGIONAL RADAR AND VISIBLE SATELLITE
IMAGERY...IT APPEARS THAT MESOSCALE CONVERGENCE/VERTICAL
CIRCULATIONS ARE SUFFICIENTLY STRONG TO INITIATE ISOLATED SCATTERED
TSTMS ALONG THIS INSTABILITY AXIS OVER THE BLACK HILLS AND WRN KS.

PLAN VIEW PROFILER/VWP DATA INDICATE THAT A BELT OF STRONGER
MID-LEVEL WINDS /25-30KTS AT 500MB/ EXISTS ACROSS ERN CO INTO KS
WITH RESULTANT 0-6KM SHEAR OF 30-35KTS. THUS...IT APPEARS THAT A FEW
OF THE DEVELOPING TSTMS COULD BECOME ORGANIZED THIS AFTERNOON AND
EVENING WITH THE POTENTIAL FOR MID-LEVEL UPDRAFT ROTATION.  
ISOLATED LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THE
STRONGEST STORMS.

...ORE/NRN CA/NWRN NV...
AIR MASS CONTINUES DESTABILIZE THIS AFTERNOON AHEAD OF
MID/UPPER-LEVEL LOW SLOWLY MOVING TOWARD THE NRN CA COAST. RUC
DIAGNOSTIC FIELDS INDICATE THAT FORCING FOR ASCENT ASSOCIATED WITH
AN UPPER-LEVEL JET STREAK IS BEGINNING TO OVERSPREAD CNTRL/NRN CA 
EARLY THIS AFTERNOON. TSTMS ARE EXPECTED TO DEVELOP LATER THIS
AFTERNOON AND EVENING AS THIS FORCING FOR ASCENT BEGINS TO ENCOUNTER
THE INSTABILITY AXIS. INCREASING MID AND UPPER-LEVEL FLOW AHEAD OF
THE APPROACHING LOW WILL RESULT IN SUFFICIENT DEEP-LAYER SHEAR FOR
ORGANIZED TSTMS...POSSIBLY EVEN SUPERCELLS WITH LARGE HAIL AND
DAMAGING WINDS.

..MEAD.. 08/04/2003

...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.

$$