[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 020620
SWODY1
SPC AC 020619

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0119 AM CDT MON AUG 02 2004

VALID 021200Z - 031200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 50 N
ISN 20 NNW P24 25 WSW JMS 60 W AXN 20 E STC 30 ENE EAU 10 NNW OSH 10
WNW MKE 25 SW CGX 15 ESE BMI 20 NW STL 35 W COU 20 ESE FNB 15 ENE
GRI 25 SE MHN 35 ENE AIA 25 N CDR 10 SE 81V 40 NE COD 20 SW WEY 55
SSE 27U 50 WSW BOI 40 SSE BNO 55 ESE RDM 40 SE DLS 40 S EPH 70 ENE
63S.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 65 ESE YUM 35 SSE EED
50 SSW DRA 55 W TPH 65 NE SVE 50 NNW SVE 15 W RBL 55 SSE EKA 15 NNE
ACV 20 N EUG 45 NE PDX 25 SSE EAT 40 NNE 63S ...CONT... 25 N PBG 35
NE BFD 35 NNE SDF 40 ESE POF 30 SSE SGF 25 SSW TOP 30 S HSI 20 S LBF
35 SE SNY LIC 40 E RTN 20 ESE TCC 15 WNW LBB 30 W ABI GGG 20 NNE MEI
15 S ANB 25 SW CSV 15 SSW JKL 20 SSW MGW 25 WNW CXY 30 ESE BOS.

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN INTERMOUNTAIN
REGION TO MT AND SEWD ACROSS THE NRN PLAINS TO THE UPPER MS
VALLEY...

...SYNOPSIS...
STRONG ZONAL FLOW CURRENTLY LOCATED ALONG THE U.S./CANADA BORDER IS
EXPECTED TO BECOME MORE AMPLIFIED TODAY.  AN UPPER RIDGE WILL BUILD
NWD ACROSS THE NRN PLAINS AND CENTRAL CANADIAN PROVINCES...AS
HEIGHTS FALL OVER THE NERN PACIFIC AND WA/ORE IN ADVANCE OF A TROUGH
MOVING SWD ALONG THE BRITISH COLUMBIA COAST.  HEIGHTS WILL ALSO FALL
ACROSS THE GREAT LAKES REGION BY LATE IN THE FORECAST PERIOD.

...ERN NEB/IA/SRN MN TO MIDWEST STATES THIS MORNING/AFTERNOON...
MCS...POTENTIALLY SEVERE...IS EXPECTED TO BE OVER PORTIONS OF ERN
NEB AND WRN/CENTRAL IA AT THE START OF THE PERIOD.  ADDITIONAL
STORMS...CURRENTLY OVER ERN ND...ARE PROGGED TO BE OVER CENTRAL MN/
WEST CENTRAL WI BY 12Z THIS MORNING.  MOSTLY CLEAR SKIES DOWNSTREAM
OF THIS EARLY MORNING ACTIVITY WILL ALLOW THE MOIST AIR MASS TO
BECOME MODERATELY UNSTABLE BY EARLY AFTERNOON. MODELS SUGGEST
CONVECTION WILL REDEVELOP AS THE EARLY MORNING CONVECTION MOVES SEWD
INTO THE DESTABILIZING ENVIRONMENT.  30-40 KT OF DEEP LAYER SHEAR
INDICATES STORMS SHOULD BE SEVERE WITH HAIL AND DAMAGING WINDS THE
PRIMARY THREATS.  MARGINAL INSTABILITY FARTHER EAST ACROSS LOWER MI
AND MODEST DEEP LAYER SHEAR MAY SUPPORT A FEW SEVERE STORMS LATE
THIS AFTERNOON AND EARLY EVENING.

...SD/NEB EWD TO SRN MN/IA THIS AFTERNOON INTO TONIGHT...
OUTFLOW BOUNDARY...LEFT OVER FROM THE MCS MOVING ACROSS ERN NEB/IA
AT THE START OF THE PERIOD...IS EXPECTED TO EXTEND FROM CENTRAL/SRN
SD TO WRN IA.  THIS BOUNDARY SHOULD BE THE EFFECTIVE FOCUS FOR
SEVERE STORMS OVER SD/NRN NEB THIS AFTERNOON...AND THEN EWD THIS
EVENING AND TONIGHT ACROSS IA AND POTENTIALLY SRN MN.  STEEP LAPSE
RATES COMBINED WITH SURFACE DEWPOINTS ALREADY IN THE 70S ACROSS
SRN-SERN SD AND NERN NEB WILL RESULT IN EXTREME INSTABILITY /MLCAPE
UP TO 4000 J/KG/ BY 21-00Z FROM SOUTH CENTRAL SD/NORTH CENTRAL NEB
ESEWD INTO WRN IA.

A SHORT WAVE TROUGH...CURRENTLY LOCATED OVER ERN ID...IS PROGGED TO
MOVE EWD INTO WRN SD BY THIS AFTERNOON.  LARGE SCALE ASCENT IN
ADVANCE OF THIS FEATURE SHOULD WEAKEN THE CAP ALONG THE SURFACE
BOUNDARY OVER PORTIONS OF CENTRAL SD/NORTH CENTRAL NEB BY MID-LATE
AFTERNOON...ALLOWING THUNDERSTORMS TO INITIATE OVER THIS AREA. 
STRONG DEEP LAYER SHEAR AND VERY STRONG TO EXTREME INSTABILITY WILL
SUPPORT SUPERCELLS WITH VERY LARGE HAIL.  BACKED LOW-LEVEL FLOW
ALONG AND NORTH OF THE BOUNDARY WILL INCREASE HODOGRAPH CURVATURE
FOR A TORNADO THREAT.

A STRENGTHENING AND VEERING LLJ OVER THE CENTRAL PLAINS AS THE ID
SHORT WAVE TROUGH MOVES INTO IA TONIGHT WILL FAVOR THE UPSCALE
DEVELOPMENT OF AFTERNOON/EARLY EVENING STORMS INTO A LINEAR MCS...
WITH THE POTENTIAL FOR WIDESPREAD DAMAGING WINDS INTO IA/SRN MN.
FORECAST INSTABILITY OVERNIGHT SUPPORTS THE WIDESPREAD DAMAGING WIND
THREAT.  THUS...PORTIONS OF THE SLIGHT RISK FROM SD/NEB EWD TO MN/IA
MAY REQUIRE AN UPGRADE TO A MODERATE RISK IN LATER OUTLOOKS...AS
PLACEMENT OF THE OUTFLOW BOUNDARY AND THE DEVELOPMENT OF AFTERNOON
ACTIVITY BECOMES MORE APPARENT IN TIME.

...MT/WRN ND...
SURFACE BOUNDARY WILL EXTEND FROM WRN MT ESEWD ALONG THE MT/WY
BORDER.  RESIDUAL SURFACE DEWPOINTS IN THE 50S COMBINED WITH STEEP
LAPSE RATES WILL RESULT IN AN AXIS OF MODERATE INSTABILITY ALONG THE
SURFACE BOUNDARY BY THIS AFTERNOON.  SWLY MID-LEVEL FLOW... THOUGH
SOMEWHAT WEAK...ATOP ESELY UPSLOPE FLOW WILL SUPPORT 30-35 KT OF
DEEP LAYER SHEAR AND THE POTENTIAL FOR SEVERE STORMS.  HAIL AND
DAMAGING WINDS WILL BE THE PRIMARY THREATS.  ACTIVITY SHOULD
CONTINUE THIS EVENING AND OVERNIGHT WITH DEVELOPMENT ALSO LIKELY
INTO WRN ND AS WAA AND ELEVATED INSTABILITY SUPPORT ISOLATED LARGE
HAIL.

...NRN INTERMOUNTAIN REGION...
HEIGHT FALLS OVER THE NERN PACIFIC WILL RESULT IN THE NWRN CA CLOSED
UPPER LOW MOVING NEWD ACROSS THE PAC NW/NRN INTERMOUNTAIN REGION
TODAY. ALTHOUGH MARGINAL INSTABILITY IS EXPECTED ACROSS THIS
REGION....COLD MID-LEVEL TEMPERATURES /-12 TO -14C AT 500 MB/ AND 35
KT SWLY MID-LEVEL FLOW IS EXPECTED TO SUPPORT NUMEROUS THUNDERSTORMS
FROM ERN PORTIONS OF WA/ORE ACROSS CENTRAL/NRN ID THIS AFTERNOON AND
EVENING.  STRONGLY MIXED BOUNDARY LAYER RESULTING IN INVERTED-V
THERMODYNAMIC PROFILES WILL FAVOR STRONG DAMAGING WINDS...BUT STEEP
LAPSE RATES SHOULD ALSO SUPPORT HAIL.

...GREAT BASIN...
FARTHER SOUTH ACROSS THE GREAT BASIN...THUNDERSTORMS ARE EXPECTED TO
DEVELOP AGAIN OVER THE HIGHER TERRAIN. WEAKER INSTABILITY WILL
LIMIT THE SEVERE COVERAGE.  HOWEVER...INVERTED-V THERMODYNAMIC
PROFILES WILL SUPPORT STRONG WIND GUSTS WITH THE MOST INTENSE
ACTIVITY.

..PETERS/GUYER.. 08/02/2004

...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.