[SWODY2] SWODY2

[SWODY2 at goshenarc.org]

ACUS02 KWNS 200759
SWODY2
SPC AC 200758

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0258 AM CDT THU MAY 20 2004

VALID 211200Z - 221200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 35 WSW
HSE 40 NE CLT LEX 35 ESE RFD 20 NW DSM 30 S HSI 15 SE AIA 40 S 81V
65 N OLF ...CONT... 50 NNW MOT 30 ESE BIS 50 WSW AXN 45 ENE OSC 15 E
BUF 45 ENE EKN 40 ESE ORF.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 ESE JAX 40 S GNV
40 SW AGR 55 WNW MIA 20 SSE MIA ...CONT... 30 ESE 7R4 30 SSW MLU 20
ENE LIT 50 ESE VIH 30 W UIN 20 SW OJC 15 E END 35 W MWL 25 SE DRT
...CONT... 60 SSW MRF 20 NNE HOB 30 SSW EHA 50 SE LIC 20 NNW SNY 40
NNE CPR 35 NNW RIW 20 WNW EVW 30 NE ELY 50 N DRA 45 SSW BIH 30 E SCK
10 SW UKI 35 NE ACV 45 N LMT 35 NE RDM 50 SE OLM 15 NNE BLI
...CONT... 40 N ART BOS.

...THERE IS A SLGT RISK OF SVR TSTMS FROM WRN SD/NEB E ACROSS THE
MID MS VLY TO LWR GRT LKS...

...SYNOPSIS...
LONG WAVE TROUGH OVER THE WRN U.S. WILL UNDERGO A FEW CHANGES THIS
PERIOD AS UPSTREAM BLOCK HOLDS FIRM IN THE E PACIFIC.  IN SHORT...
EXPECT MAJOR PORTION OF THE TROUGH TO EJECT NEWD IN PIECEMEAL
FASHION DURING THE NEXT TWO DAYS...WHILE A NEW CLOSED LOW
/ASSOCIATED WITH SPEED MAX NOW TOPPING RIDGE IN AK/...DEVELOPS IN
ITS PLACE OVER SRN BC. AT THE SAME TIME...SRN PLNS RIDGE SHOULD
EXPAND E INTO THE WRN ATLANTIC.  THIS WILL MAINTAIN MODERATE SW TO
WSW FLOW FROM THE CNTRL/NRN PLNS ACROSS THE MID/UPR MS VLY TO THE
LWR GRT LKS.

AT LWR LEVELS...COLD FRONT CROSSING THE GRT LKS REGION TODAY SHOULD
BECOME STATIONARY FROM THE MID MS VLY TO MID ATL CST BY 12Z FRIDAY. 
WRN PART OF BOUNDARY SHOULD LIFT SLIGHTLY N ACROSS THE NRN HALF OF
THE CNTRL PLNS DURING THE PERIOD...AHEAD OF LEAD IMPULSE EJECTING NE
FROM WRN TROUGH.

...WRN SD/NEB THROUGH MID MS VLY TO LWR GRT LKS/MID ATL...
WARM/STATIONARY FRONT EXTENDING FROM THE PLNS TO THE E CST WILL
SERVE AS A FOCUS FOR PERIODIC STRONG TO SEVERE THUNDERSTORM
DEVELOPMENT THROUGH THE PERIOD.  TIMING OF THESE CONVECTIVE SYSTEMS
WILL REMAIN UNCERTAIN GIVEN /1/ LOW AMPLITUDE OF SW/WSWLY FLOW ALOFT
AND /2/ CONTINUING EFFECT OF ELEVATED MIXED LAYER CAP FROM THE PLNS
TO MID MS VLY.

A FEW AREAS OF MAINLY ELEVATED STORMS MAY BE PRESENT AT THE START OF
THE PERIOD OVER ERN SD/IA/SRN MN AND WI.  STRONG /40+ KT/ SWLY LOW
LEVEL JET IN THIS REGION WILL CONTRIBUTE TO MODERATE DEEP SHEAR AND
STRONG CLOUD-LAYER INSTABILITY /CAPE TO 2000 J/KG/... POSING A
THREAT FOR HAIL AND POSSIBLY HIGH WIND.

SCATTERED SURFACE-BASED STORMS COULD FORM LATER IN THE DAY ALONG
OUTFLOW FROM THIS ACTIVITY AND/OR ALONG MAIN SURFACE FRONT FROM SRN
WI/CNTRL AND SRN MI SEWD INTO PARTS OF IND/OH/WRN PA/WRN NY... WHERE
AMPLE /35-40 KT /DEEP WLY SHEAR WILL EXIST TO SUPPORT
ORGANIZED STORMS/SUPERCELLS WITH HIGH WIND.  SUSTAINED ROTATING
CELLS WOULD ALSO POSE A THREAT FOR HAIL AND ISOLATED TORNADOES
...ESPECIALLY IN SRN MI/IND/OH WHERE MLCAPE COULD REACH 3000 J/KG
AND SURFACE WINDS COULD REMAIN MORE SLY.  A FEW STRONG DIURNAL
CELLS/ CLUSTERS COULD ALSO DEVELOP INVOF FRONT FARTHER SE INTO WV/VA
AND NRN NC.

SURFACE-BASED ACTIVITY MAY ALSO DEVELOP WWD WITH TIME INTO MORE
STRONGLY CAPPED ENVIRONMENT ACROSS NRN IL AND IA...BUT CONFIDENCE
REMAINS LOW ON THIS SCENARIO GIVEN STRENGTH OF CAP AND ABSENCE OF A
WELL-DEFINED SHORTWAVE DISTURBANCE ALOFT.

A SEPARATE AREA OF STORM INITIATION MAY EMERGE OVER THE WRN PARTS OF
THE DAKS AND NEB FRIDAY AFTERNOON...INVOF LEE TROUGH/WARM FRONT. 
THESE FEATURES WILL LIFT NEWD THROUGH THE DAY AHEAD OF LEAD
DISTURBANCE EJECTING NEWD IN SW FLOW ALOFT /THE IMPULSE NOW ENTERING
NV/.  GIVEN PROXIMITY TO MAIN UPPER JET /SPEEDS AOA 40 KT/...STEEP
MID LEVEL LAPSE RATES AND INCREASINGLY MOIST SELY BOUNDARY LAYER
FLOW AHEAD OF FRONT...SETUP COULD SUPPORT A FEW SUPERCELLS WITH
HAIL/HIGH WIND AND A FEW TORNADOES.  POTENTIAL WOULD ALSO EXIST FOR
UPSCALE DEVELOPMENT INTO A FORWARD PROPAGATING CLUSTER.  THIS SYSTEM
MAY REACH THE LWR MO VLY BY SATURDAY MORNING...AND MERGE WITH OTHER
ACTIVITY ASSOCIATED WITH STRENGTHENING OF THE LOW LEVEL JET OVER THE
MID/UPR MS VLY.

..CORFIDI.. 05/20/2004

...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.