[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 221254
SWODY1
SPC AC 221251

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0751 AM CDT SAT MAY 22 2004

VALID 221300Z - 231200Z

THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 10 WNW
MCK IML 30 ESE AIA 40 WSW VTN 60 ENE ANW 10 NNW SPW 20 SW RST 25 SSE
ALO 45 WSW CID 15 NE LWD 20 SE BIE 40 SSE HSI 10 WNW MCK.

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM ART 35
SSE SLK RUT EEN BDL 35 NNE EWR TTN PHL 15 NW NHK 40 ENE LYH ROA BKW
PKB CMH MIE BMI UIN 30 N SZL PNC FSI CDS 30 W RSL 25 WNW HLC 35 W
GLD 10 NNE LIC 30 ENE DEN 55 N DGW SHR BIL 70 WNW MLS 45 SSE GDV 55
NW PHP 20 NNW 9V9 35 NW OTG 40 N RST CWA 45 NW MBL 15 S OSC.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 S MOB 45 ESE LUL
20 WSW MSL 50 NNE MSL 25 WNW BNA 35 N HOP 45 SW BLV 40 NNW SGF BVO
35 NNW ADM MWL 30 S BWD 15 NW DRT ...CONT... 50 SW MRF 20 ENE MRF 15
W MAF 35 WNW CDS 25 W GAG 40 WSW RSL 40 W HLC LIC ASE 20 SSE U24 ELY
4LW 40 SE EUG 20 NNW ONP ...CONT... 55 N FCA 20 WSW HVR 30 W GGW 20
SSW ISN 20 N BIS 50 NW ABR 25 ENE ABR 45 NE ATY 70 SSW DLH 30 WNW
IMT 40 E PLN ...CONT... 30 N BML 40 SW BHB ...CONT... 20 SE DAB 35 N
PIE.

...THERE IS A MDT RISK OF SVR TSTMS W-CENTRAL NEB TO E-CENTRAL IA...

...THERE IS A SLGT RISK OF SVR TSTMS CENTRAL HIGH PLAINS TO MID
ATLANTIC/PIEDMONT REGION AND WRN OK...

...SYNOPSIS...
SHORTWAVE TRANSITION UNDERWAY WITHIN BROADER WRN CONUS TROUGH. 
MID-UPPER LEVEL CYCLONE IS DEVELOPING ATTM OVER SRN BC...AND WILL
MAKE CYCLONICALLY CURVING PATH ACROSS PACIFIC NW TO NRN ROCKIES BY
END OF PERIOD. AS THIS OCCURS...SHORTWAVE TROUGH -- NOW EVIDENT IN
MOISTURE CHANNEL IMAGERY OVER LOWER CO RIVER VALLEY -- IS EXPECTED
TO EJECT ENEWD TO NEWD TODAY ACROSS 4-CORNERS AREA AND SRN ROCKIES. 
THIS WILL MAINTAIN -- PERHAPS SLIGHTLY DEEPEN -- COMBINED
LEE-SIDE/FRONTAL-WAVE SFC CYCLONE NOW ANALYZED OVER W-CENTRAL
PORTION KS/NEB BORDER. THIS LOW SHOULD MOVE EWD OR ENEWD TOWARD
SERN NEB/SWRN IA REGION BY 23/06Z...WHILE COLD FRONT MOVES SEWD
ACROSS CENTRAL HIGH PLAINS.  MEANWHILE...DRYLINE PRESENTLY FROM
KS/NEB LOW SWWD ACROSS NWRN TX PANHANDLE AND ERN NM IS FCST TO MIX
EWD TODAY TOWARD 100TH MERIDIAN IN KS...SWD ALONG TX/OK BORDER THEN
SWWD ACROSS W TX.

...SRN NEB/NRN KS TO MS VALLEY...
AFTERNOON SUPERCELLS WITH HAIL/WIND/TORNADO THREAT SHOULD BE
FOLLOWED BY NOCTURNAL MCS WITH DAMAGING WIND AND OCCASIONAL LARGE
HAIL. GREATEST POTENTIAL FOR TORNADOES -- SOME STRONG -- WOULD BE
INVOF FRONTAL/OUTFLOW BOUNDARY AND N-E OF SFC LOW ACROSS
S-CENTRAL/SERN NEB INTO SWRN IA...WHERE GREATEST COMBINATION OF
SHEAR/INSTABILITY/MOISTURE IS FCST...AND LCL SHOULD BE RELATIVELY
LOW.  18Z SOUNDINGS PLANNED OVER THIS REGION TO FURTHER ASSESS
DIURNAL AIR MASS EVOLUTION.

OUTFLOW BOUNDARY FROM EARLIER CONVECTION -- NOW OVER WRN/CENTRAL IA
-- HAS SHUNTED EFFECTIVE FRONTAL ZONE SWD TO NEAR KS/NEB BORDER. 
EXPECT THIS BOUNDARY TO STALL IN THAT AREA NEXT SEVERAL HOURS THEN
DRIFT NWD...AS FLOW TO ITS N VEERS FROM NELY TO ELY AND ESELY. THIS
WILL YIELD FAVORABLE LOW LEVEL HODOGRAPHS INVOF BOUNDARY THIS
AFTERNOON FOR SUPERCELLS.  AIR MASS NEAR BOUNDARY -- E OF SFC LOW --
WILL BECOME EXTREMELY UNSTABLE AS 8-9 DEG C/KM MIDLEVEL LAPSE RATES
OVERLIE SFC DEW POINTS EVAPOTRANSPIRATIVELY BOOSTED INTO UPPER
60S/LOW 70S F. ANY CONVECTION INITIATING NEAR SFC LOW AND EWD ALONG
BOUNDARY SHOULD BECOME SEVERE QUICKLY...AMIDST MLCAPE 3500-5000
J/KG...50 KT 500 MB FLOW AND 50-60 KT 0-6 KM AGL SHEAR.  THIS
SUGGESTS DESTRUCTIVE HAIL IS LIKELY FROM A FEW STORMS IN ADDITION TO
AFOREMENTIONED TORNADO THREAT.

ANOTHER NOCTURNAL MCS OR TWO SHOULD EVOLVE FROM THIS ACTIVITY AND/OR
EWD MOVEMENT OF HIGH PLAINS CONVECTION DISCUSSED BELOW...SHIFTING
EWD ACROSS MO AND MS VALLEYS TONIGHT WITH SEVERE WIND/HAIL
POTENTIAL.

...NRN/CENTRAL HIGH PLAINS...
BOUNDARY LAYER MOIST AXIS -- N OF SFC COLD FRONT -- SHOULD EXTEND
FROM CENTRAL NEB WWD INTO HIGHER TERRAIN OF SERN WY/NERN CO/NEB
PANHANDLE DURING MID-LATE AFTERNOON AND CONTRIBUTE TO DEVELOPMENT OF
SEVERE TSTMS.  THIS POTENTIAL MAY EXTEND NWWD OVER FOOTHILLS TOWARD
SERN MT -- FOR RELATIVELY SHORT-LIVED WINDOW OF SEVERE POTENTIAL
FROM LATE AFTERNOON INTO EARLY EVENING.  LARGE HAIL AND DAMAGING
WIND ARE POSSIBLE.  SEVERE PROBABILITIES ARE RELATIVELY MAXIMIZED
ACROSS NEB WHERE DIURNAL HEATING COMBINED WITH UPSLOPE ADVECTION OF
MOISTURE CONTRIBUTE TO MLCAPE 2000-3000 J/KG -- INCREASING WITH EWD
EXTENT.  STORM-RELATIVE BOUNDARY LAYER FLOW AND ENLARGED HODOGRAPHS
ARE POSSIBLE GIVEN POTENTIAL FOR 15-20 KT ELY FLOW COMPONENT OVER
REGION.

...CENTRAL KS TO NW TX...
ISOLATED TO WIDELY SCATTERED TSTMS ARE POSSIBLE ONCE AGAIN INVOF
DRYLINE FOR SEVERAL HOURS DURING LATE AFTERNOON AND EARLY EVENING. 
ACTIVITY WILL BE STRONGLY DRIVEN BY DIABATIC HEATING AND DRYLINE
LIFT BREAKING OTHERWISE STRONG CAP...WITH RELATIVELY HIGH LFC
SUGGESTING LIMITED TORNADO POTENTIAL.  HOWEVER...LARGE HAIL AND
STRONG-SEVERE GUSTS ARE POSSIBLE...WITH FAVORABLE VERTICAL SHEAR FOR
SUPERCELLS SPREAD ACROSS GREATER PORTION OF DRYLINE THAN PREVIOUS
DAYS.  MODIFIED FCST SOUNDINGS ACROSS WRN OK INDICATE MLCAPE
APPROACHING 3000 J/KG...GRADUALLY INCREASING NWD ACROSS CENTRAL KS. 
COVERAGE/DURATION OF TSTMS -- AND ACCORDINGLY...SEVERE PROBABILITIES
-- SHOULD DECREASE WITH SWD EXTENT FROM WRN OK INTO W TX...AND SHEAR
WILL WEAKEN SWD AS WELL.

...SRN GREAT LAKES/OH VALLEY REGION...
EITHER OF TWO ONGOING MCS ACROSS NRN IL...SRN IA AND NRN MO MAY
INTENSIFY LATER THIS MORNING INTO AFTERNOON AS A FORWARD-PROPAGATING
CONVECTIVE SYSTEM.  ACTIVITY MAY MOVE EWD ACROSS PORTIONS
IL/INDIANA/OH...PRODUCING DAMAGING WIND AS FOREGOING AIR MASS
DIABATICALLY DESTABILIZES...PROVIDING SFC-BASED BUOYANCY IN INFLOW
SECTOR.  THIS PROBABILITY IS TOO CONDITIONAL ATTM TO RAISE
CATEGORICAL RISK...HOWEVER ANOTHER PROGRESSIVE DERECHO EVENT IS
POSSIBLE AND POTENTIAL CONCENTRATION OF DAMAGING WIND EVENTS COULD
COMPEL UPGRADE DURING DAY.  MIDAFTERNOON MLCAPES SHOULD BE IN
2500-3500 J/KG RANGE ATOP WELL MIXED...WEAKLY CAPPED...AND NEARLY
200 MB DEEP BOUNDARY LAYER.

...NERN CONUS...
THERMODYNAMIC AND KINEMATIC FIELDS -- FROM N-CENTRAL APPALACHIANS
AND UPPER OH VALLEY EWD TOWARD MID ATLANTIC AND TIDEWATER -- HAVE
BEEN JUMBLED BY PASSAGE OF CONVECTIVE COMPLEX FROM PREVIOUS DAY. 
STILL...SUFFICIENT DESTABILIZATION IS EXPECTED LATE THIS MORNING AND
INTO THIS AFTERNOON TO SUPPORT TSTMS WITH DAMAGING GUSTS AND
ISOLATED LARGE HAIL.  ACTIVITY MAY DEVELOP OVER AREA AS RELATIVELY 
DISCRETE CELLS OR SMALL CLUSTERS...AND/OR MOVE EWD FROM OH
VALLEY/GREAT LAKES REGION AS MORE ORGANIZED MCS.  DEEP-LAYER FLOW
SHOULD BECOME EARLY UNIDIRECTIONAL...VERTICAL SHEAR INCREASING WITH
NWD EXTENT AND BUOYANCY GENERALLY INCREASING SWD.

...INTERIOR NW...
WIDELY SCATTERED TO SCATTERED TSTMS ARE EXPECTED THIS AFTERNOON
AMIDST ENVIRONMENT OF WEAK CINH...INCREASING VERTICAL SHEAR AND
STRENGTHENING LARGE SCALE ASCENT.  LOW LEVEL COLD FRONT IS EXPECTED
TO MOVE EWD ACROSS REGION DURING PERIOD OF PEAK HEATING...FURTHER
CONTRIBUTING TO CONVECTIVE POTENTIAL.  SOME OF THIS ACTIVITY MAY
PRODUCE HAIL AND GUSTS NEAR SEVERE LEVELS WITH MLCAPE 300-800 J/KG.

..EDWARDS/GUYER.. 05/22/2004

...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.