STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK 
DAY 2 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWI47 KWBC. 

VALID 011200Z - 021200Z 

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 20 WNW SHR
50 NNW MLS 15 WNW SDY 30 WSW DVL 15 NNW FAR 35 WNW AXN 35 S AXN 20 S OTG
45 E SUX 25 NW OMA 25 N GRI 20 ESE BBW 55 SW MHN 40 NW BFF 30 NNE CPR 20
WNW SHR. 

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 20 ESE SBY
40 N RIC 25 ESE SSU HTS 40 W UNI 20 NNW ZZV 10 NNW FKL 15 NNE BFD 20 NW
ITH 20 N UCA 25 SSW BTV 25 ENE MPV BHB. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 W RRT 40 NNE BRD 40
SSW LSE 20 E MMO 30 NNW FWA 45 NNE MTC. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 65 S GBN 20 NNW PRC 70
NNE INW AMA 25 SW OKC 10 NW HOT 35 ENE UNO 40 N COU 20 SSW BIE MCK 20
WNW CYS 30 SE LND 45 NNE BPI JAC 15 SSW WEY BTM 45 NNE MSO 50 NE FCA. 

...SYNOPSIS... 

INTENSE TROUGH DIGS SEWD INTO NEW ENGLAND BY SUNDAY NIGHT 
ACCOMPANIED BY A VIGOROUS COLD FRONT AND VERY STRONG MID/UPPER JET.
LARGE UPPER HIGH CENTERED OVER CENTRAL ROCKIES WILL KEEP WLYS ACROSS NRN
ROCKIES AND LOW LEVEL SLYS HIGH PLAINS. 

...NERN U.S... 

GIVEN THE FORECASTED INTENSITY OF UPPER TROUGH MOVING ACROSS NERN 
U.S. SUNDAY...POTENTIAL EXISTS FOR A SIGNIFICANT EPISODE OF SEVERE
THUNDERSTORMS ALONG AND AHEAD OF STRONG COLD FRONT.  ETA IN PARTICULAR
SEEMS TO UNDERDO AMOUNT OF INSTABILITY THAT WILL BE AVAILABLE AHEAD OF
COLD FRONT AS SUNDAY AFTERNOON TEMPERATURES SHOULD STILL BE WELL INTO
THE 80S WITH DEWPOINTS TO NEAR 70F.  THIS RESULTS IN CAPES ABOVE 2000
J/KG GENERALLY FROM PA EWD ACROSS SRN NEW ENGLAND. 

SURFACE LOW DEEPENS DURING DAY N OF ST LAWRENCE VALLEY WITH APPROACH OF
150M HEIGHT FALLS WITH STRONG TROUGH. THIS RESULTS IN GENERALLY
UNIDIRECTIONAL SHEAR PROFILES EXCEPT FOR NRN NEW ENGLAND JUST AHEAD OF
SURFACE LOW WHERE LOW LEVELS ARE MORE SLY.  

A SQUALL LINE IS EXPECTED TO FORM ALONG/AHEAD OF COLD FRONT BY EARLY
AFTERNOON ACROSS NRN NY SWWD INTO WRN PA WITH PREDOMINANTLY WIND DAMAGE
THREAT AS STORMS WILL BE MOVING VERY RAPIDLY WITH APPROACH OF 80KT 500
MB WIND MAX.  

EWD ACROSS SRN ENGLAND...GREATER POTENTIAL FOR LOW LEVEL BACKED FLOW LEE
OF APPALACHIANS...WHICH WILL POSSIBLY SUPPORT SUPERCELL DEVELOPMENT
ALONG WITH ISOLATED TORNADOES. 

MUCH OF THIS AREA WILL LIKELY BE UPGRADED IN LATER OUTLOOKS  AS
SITUATION APPEARS TO HAVE CONSIDERABLE POTENTIAL.   

..HALES.. 06/30/01



STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK 
DAY 2 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWI47 KWBC. 

VALID 011200Z - 021200Z 

THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM BOS 10 W
PVD GON ISP TTN CXY 35 ENE AOO PSB ELM UCA MPV MWN PSM BOS. 

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM ACY DCA
CRW HTS 40 N SDF BMG HUF DNV LAF FWA MFD YNG ART MSS. 

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM DGW 20 WSW
SHR LVM BZN HLN GTF 60 NNE LWT GDV Y22 30 NE PHP 25 SSE PIR HON BKX OTG
SPW 50 WSW FOD OMA 25 SSE OLU BBW 25 ESE LBF IML SNY DGW. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 80 SSE GBN PRC FLG GUP
DRO GUC ASE EGE CAG JAC DLN 3DU 55 NW CTB ...CONT... 80 NW GGW ISN BIS
FAR 35 N AXN STC 40 ENE MCW DBQ CGX 20 S MTC. 

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM HLC GCK LBL 35 E AMA 55
SSW CDS 35 NNE ABI MWL FTW DAL PGO 60 ESE HRO UNO TBN OJC CNK HLC. 

--- SYNOPSIS --- 

FAST MID-UPPER LEVEL FLOW BELT ACROSS NRN CONUS AND SRN CANADA IS
FORECAST TO BUCKLE SOMEWHAT DURING DAY-2 AS WRN RIDGE AMPLIFIES AND
SEASONABLY INTENSE SHORTWAVE TROUGH DIGS SEWD THROUGH GREAT LAKES
REGION.  ASSOCIATED SURFACE COLD FRONT -- NOW OBSERVED OVER PORTIONS
SRN/WRN QUE AND NRN ONT -- WILL REMAIN QUITE STRONG AS IT SWEEPS SEWD
ACROSS NERN STATES...GREAT LAKES AND OH VALLEY. MEANWHILE...NNE-SSW
ORIENTED TROUGH FROM IL SWWD ACROSS S TX WILL WEAKEN SOMEWHAT AS PRIMARY
MID LEVEL VORTICITY MAX DRIFTS SWWD FROM OZARKS TO ARKLATEX REGION.  A
CONVECTIVELY INDUCED/ENHANCED SHORTWAVE TROUGH NOW OVER SRN SD/NRN NEB
SHOULD TURN SSWWD ACROSS SRN PLAINS BETWEEN 4-CORNERS ANTICYCLONE AND
OZARKS CIRCULATION. WRN PORTION OF SURFACE FRONT WILL STALL OVER
CENTRAL/NRN HIGH PLAINS...BENEATH SWRN PERIPHERY OF STRONGER UPPER LEVEL
NWLYS. 

--- NERN CONUS --- 

POTENTIAL EXISTS FOR SIGNIFICANT TSTM WIND DAMAGE EVENT.  UNUSUALLY
INTENSE KINEMATIC FIELDS FOR SUMMERTIME WILL OVERLIE PARTS OF A RICHLY
MOIST AND UNSTABLE WARM SECTOR.  CONVECTIVE COVERAGE SHOULD BE MAXIMIZED
ALONG FRONT AND ANY PREFRONTAL MESOSCALE CONVERGENCE ZONES WHICH MAY
DEVELOP...RESULTING IN A FEW BANDS OF SEVERE CONVECTION.  ATTM IT
APPEARS GREATEST THREAT WILL BE ERN NY INTO CENTRAL NEW ENGLAND REGION
IN 18-00Z TIME FRAME...BUT THIS IS SUBJECT TO SOME ADJUSTMENT IN FUTURE
UPDATES.  

AHEAD OF INTENSE GREAT LAKES TROUGH...110-120 KT UPPER LEVEL SPEED
MAXIMA AND 50-90 KT MID LEVEL FLOW WILL CONTRIBUTE TO STRONG VERTICAL
SHEAR OVER THIS REGION IN A LARGELY UNIDIRECTIONAL VERTICAL WIND
PROFILE.  SURFACE DEW POINTS IN UPPER 60S/LOW 70S F NOW OBSERVED OVER
MUCH OF AREA SHOULD BE MAINTAINED AFTER ANY DAY-1 CONVECTION AS LOW
LEVEL WLYS ADVECT ADDITIONAL HIGH-THETAE AIR INTO REGION.  AFTERNOON
TEMPS EXCEEDING 80 F SHOULD BE COMMON DESPITE POTENTIAL AREAS OF HIGH
CLOUD COVER...WITH 90S IN RELATIVELY CLEAR AREAS...AND SBCAPE RISING
INTO 2000-3000 J/KG RANGE.  SEVERE THREAT SHOULD EXTEND TO COASTAL AREA
BY LATE AFTERNOON/EARLY EVENING... WITH WLY COMPONENT OF BOUNDARY LAYER
FLOW KEEPING SEA BREEZE NEAR SHORE. 

SECONDARY POTENTIAL EXISTS FOR LARGE HAIL AND A FEW TORNADOES.  AIR MASS
SHOULD NOT BE STRONGLY CAPPED -- SO DISCRETE SUPERCELLS MAY DEVELOP
GIVEN THE STRENGTH OF DEEP-LAYER SHEAR...E.G. 0-6 KM AGL VECTOR SHEAR
NEAR 50 KT AND 60-70 J/KG BRN SHEAR IN FORECAST SOUNDINGS. 

..EDWARDS.. 06/30/01