[SWODY2] SWODY2

[SWODY2 at goshenarc.org]

ACUS02 KWNS 171742
SWODY2
SPC AC 171740

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1240 PM CDT MON MAY 17 2004

VALID 181200Z - 191200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM HUL 20
NNE PSM 10 N BDR DOV HGR 20 W MGW EVV HRO 10 SE END GAG EHA 10 SSE
LAA DEN CPR 20 ENE COD 10 NW BIL GDV 20 NW MBG OFK 15 SE OMA 50 NNE
SZL UIN 25 N PIA 20 S ARB 20 SE DTW.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 70 NNE DVL FAR 20 SSW
BKX FSD DSM 10 SE JVL MKG 60 ESE OSC ...CONT... 35 NNW ORF 10 NE RDU
CAE AGS AYS GNV 55 W ORL 10 SSE SRQ ...CONT... 35 S PSX 60 E CLL 35
ESE SHV 40 SSW JBR MKO CSM 10 SE DHT PUB 45 ESE ASE MTJ U17 10 SE
CDC 55 NW MLF 10 SE ENV 20 SE OWY SVE 10 S RBL MFR 10 SE RDM SEA 35
W BLI.

...THERE IS A SLGT RISK OF SVR TSTMS TUESDAY/TUESDAY NIGHT ACROSS A
LARGE PART OF THE NRN/CNTRL U.S....

...OHIO VALLEY/GREAT LAKES INTO NORTHEAST STATES...
SERIES OF SHORT WAVES ARE EVIDENT IN LATEST WATER VAPOR IMAGERY...
PROGRESSING THROUGH BROAD UPPER TROUGH WHICH PERSISTS ACROSS MUCH OF
THE CENTRAL/EASTERN CANADIAN PROVINCES.  THIS INCLUDES POSITIVELY
TILTED SHORT WAVE TROUGH OVER MANITOBA/SASKATCHEWAN...WHICH ALREADY
APPEARS TO BE TURNING EASTWARD TOWARD ONTARIO/QUEBEC AND THE UPPER
GREAT LAKES REGION. MODELS SUGGEST THAT AS THIS MOTION CONTINUES...
SYSTEM WILL GRADUALLY MERGE WITH WEAKER SHORT WAVE TROUGH EMANATING
FROM BROADER SCALE NORTHWESTERN U.S. UPPER TROUGH.

BY EARLY TUESDAY ...A STRENGTHENING LOW-LEVEL BAROCLINIC ZONE AND
INTENSIFYING MID/UPPER JET STREAK IS PROGGED OVER THE LOWER GREAT
LAKES REGION.  AS UPPER TROUGH AXIS CONTINUES EASTWARD INTO/THROUGH
THE ST. LAWRENCE VALLEY DURING THE COURSE OF THE REMAINDER OF THE
FORECAST PERIOD...FRONTAL ZONE WILL ADVANCE SOUTHWARD/SOUTHEASTWARD
INTO THE OHIO VALLEY AND NORTH ATLANTIC COASTAL AREAS. DURING THE
LATE AFTERNOON HOURS...NEAR/SHORTLY AFTER PEAK HEATING...MODELS
SUGGEST FRONT WILL PROGRESS SOUTHEAST OF LAKES
ONTARIO/ERIE...PROVIDING FORCING/FOCUS FOR INCREASING CONVECTIVE
DEVELOPMENT.

THOUGH MID-LEVEL LAPSE RATES DO NOT APPEAR LIKELY TO BECOME
PARTICULARLY STEEP...FAIRLY STRONG SURFACE HEATING SHOULD OCCUR
ACROSS MUCH OF OHIO/PENNSYLVANIA/AND NEW YORK STATE.  THIS WILL
CONTRIBUTE TO STEEP LOW-LEVEL LAPSE RATES...WITH SUFFICIENT BOUNDARY
LAYER MOISTURE FOR MEAN MIXED LAYER CAPE IN EXCESS OF 1000 J/KG...
SUPPORTIVE OF VIGOROUS UPDRAFTS WITH POTENTIAL FOR LARGE HAIL. 
THERMODYNAMIC ENVIRONMENT WILL ALSO BE FAVORABLE FOR DAMAGING WIND
GUSTS...WITH THIS RISK ENHANCED BY 40 KT MEAN FLOW REGIME ON
SOUTHERN FRINGE OF STRONGER WESTERLIES.

SEVERAL LINES OF STRONG/SEVERE STORMS APPEAR LIKELY TO EVOLVE
THROUGH THE LATE TUESDAY AFTERNOON/EVENING...PERHAPS MERGING INTO
ONE EXTENSIVE SQUALL LINE ORIENTED IN EAST-WEST BAND ALONG FRONTAL
ZONE..FROM NEW ENGLAND AND THE HUDSON VALLEY THROUGH THE OHIO
VALLEY.  ACTIVITY WILL CONTINUE SLOWLY SOUTHWARD LATE TUESDAY
NIGHT...BUT SHOULD SLOWLY DIMINISH IN INTENSITY ACROSS THE NORTHERN
MID ATLANTIC COAST REGION/NORTH CENTRAL APPALACHIANS/AND AREAS NEAR
THE OHIO RIVER.

...CENTRAL PLAINS INTO NORTHERN ROCKIES..
STRONG WESTERLY MID/UPPER JET STREAK IS CURRENTLY NOSING INTO THE
NORTH CENTRAL PACIFIC COAST.  MODELS SUGGEST THIS FEATURE...AND
ASSOCIATED EVOLVING CLOSED LOW...WILL GRADUALLY PROGRESS ACROSS THE
NORTHERN INTERMOUNTAIN REGION INTO THE NORTH CENTRAL ROCKIES LATE
TUESDAY AFTERNOON AND EVENING. IN RESPONSE...STRENGTHENING
SOUTHEASTERLY MOIST UPSLOPE FLOW WILL CONTRIBUTE TO
DESTABILIZATION...AND INCREASINGLY FAVORABLE SHEAR PROFILES FOR
SUPERCELLS BY PEAK HEATING...FROM THE FRONT RANGE OF THE ROCKIES
INTO SOUTHEAST MONTANA.

ACTIVITY WILL LIKELY CONSOLIDATE IN STRONG WARM ADVECTION REGIME
ALONG STRENGTHENING SOUTHERLY LOW-LEVEL JET AXIS ACROSS WESTERN
NEBRASKA AND THE WESTERN DAKOTAS TUESDAY EVENING. RISK OF LARGE HAIL
AND DAMAGING WIND GUSTS MAY PERSIST INTO THESE AREAS...BUT AS
LOW-LEVEL JET VEERS OVERNIGHT...LARGE HAIL WILL BECOME PRIMARY
THREAT AS ACTIVITY BECOMES INCREASINGLY BASED ABOVE SURFACE BASED
INVERSION LAYER ACROSS THE EASTERN DAKOTAS.

...SOUTH CENTRAL PLAINS INTO OZARKS...
CONSIDERABLE UNCERTAINTY EXISTS WITH REGARD TO CONVECTIVE
DEVELOPMENT OVER THE CENTRAL PLAINS.  MID-LEVEL RIDGE IS PROGGED TO
EXPAND NORTHWARD OUT OF THE SOUTHERN PLAINS...WHICH WILL LIKELY CAP
VERY MOIST AND POTENTIALLY UNSTABLE BOUNDARY LAYER. 
HOWEVER...LATEST WATER VAPOR IMAGERY SUPPORTS MODEL PROGS WHICH
SUGGEST WEAK SHORT WAVE TOPPING THIS RIDGE EARLY TUESDAY...ACROSS
THE OZARKS.  CLUSTER OF STORMS COULD DEVELOP IN ASSOCIATION WITH
THIS FEATURE...ON NOSE OF SOUTHERLY LOW-LEVEL JET...WHICH MAY
PERSIST AS STRONGER MID-LEVEL FORCING SHIFTS TOWARD THE LOWER OHIO
VALLEY TUESDAY AFTERNOON/EVENING.

..KERR.. 05/17/2004

...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.