[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 090550
SWODY1
SPC AC 090548

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1248 AM CDT MON MAY 09 2005

VALID 091200Z - 101200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 45 N
APN 20 W DAY 25 SE SDF 10 WNW HOP 25 ESE LIT 30 ESE PGO 15 W MKO 40
S CNU 50 NNE JLN 20 SW BRL 20 SE LSE 55 NW EAU 65 NW CMX.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 80 ENE 63S 25 NW LWT
55 SSW MLS 45 SE REJ 50 S 9V9 35 SSE YKN 15 WSW FOD 15 SSW FRM 15
WSW RWF ATY 25 WSW ABR 50 ESE BIS 35 WSW DVL 70 NNE DVL ...CONT...
50 ESE MTC 20 NW CRW 40 E TRI 20 SW AHN PFN ...CONT... 15 SE PSX 20
NNE CRP 25 SW ALI 70 S LRD ...CONT... DRT 10 NW ABI 30 NNE CDS 35
SSE LBL 50 E LAA 45 SSE LIC COS 35 WSW MTJ 50 ESE SGU 40 E DRA 60 W
DRA 40 SSE FAT MRY.

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER GREAT LAKES SWWD
INTO THE OZARKS...

...SYNOPSIS...
MID-LEVEL TROUGH WILL CONTINUE MOVING EWD ACROSS THE CENTRAL U.S.
THIS PERIOD...WHILE STRONGER / CLOSED LOW MOVES ONSHORE OVER THE WRN
CONUS.

SURFACE LOW ASSOCIATED WITH CENTRAL U.S. TROUGH IS FORECAST TO MOVE
EWD TOWARD THE UPPER LAKES...WHILE ATTENDANT COLD FRONT CROSSES THE
UPPER MS VALLEY DURING THE AFTERNOON.  TRAILING PORTION OF THIS
BOUNDARY -- EXTENDING SWWD INTO THE CENTRAL AND SRN PLAINS -- SHOULD
WEAKEN / RETURN NWD ACROSS KS LATER IN THE PERIOD.  THOUGH MAIN
SEVERE THREAT THIS PERIOD IS FORECAST AHEAD OF CENTRAL U.S. STORM
SYSTEM...LIMITED THREAT FOR HAIL / WIND ALSO APPEARS TO EXIST OVER
PARTS OF THE GREAT BASIN AND VICINITY AHEAD OF WRN UPPER LOW.  

...UPPER GREAT LAKES SWWD INTO THE OZARKS...
CONVECTION SHOULD BE ONGOING ACROSS PARTS OF THE UPPER MS VALLEY 
REGION AT THE START OF THE PERIOD...INVOF SURFACE LOW / VORT MAX
FORECAST OVER THE ERN DAKOTAS. NAM / NAMKF ALSO SUGGEST STORMS WELL
E OF FRONT INTO IL / INDIANA EARLY IN THE PERIOD...WHICH SEEMS
REASONABLE GIVEN STORMS NOW DEVELOPING OVER ERN IA / WRN IL.  THOUGH
THIS ONGOING CONVECTION MAY LIMIT DIURNAL HEATING / DESTABILIZATION
IN SOME AREAS...UPPER 50S / LOW 60S DEWPOINTS AHEAD OF FRONT SHOULD
CONTRIBUTE TO 500 TO 1000 J/KG MEAN-LAYER CAPE IN AREAS WHICH
RECEIVE AMPLE HEATING. 

CONVECTIVE DEVELOPMENT IS ANTICIPATED INVOF COLD FRONT BY
AFTERNOON...WHILE SOME CONVECTIVE INTENSIFICATION / REDEVELOPMENT IS
EXPECTED WITH PRE-FRONTAL STORMS WHICH SHOULD BE MOVING ACROSS
INDIANA BY AFTERNOON.  DEGREE OF INSTABILITY COMBINED WITH 30 TO 40
KT SSWLY MID-LEVEL FLOW FROM IL / IN NWD SHOULD SUPPORT ORGANIZED
CONVECTION...WITH A COMBINATION OF SMALL-SCALE LINEAR CLUSTERS AS
WELL AS MULTICELL / WEAK SUPERCELL STORMS ANTICIPATED. THOUGH MAIN
SEVERE THREATS WILL BE HAIL AND LOCALLY-DAMAGING WINDS...A TORNADO
OR TWO WILL ALSO BE POSSIBLE -- WITH GREATEST THREAT ATTM EXPECTED
ACROSS PARTS OF WI / WRN UPPER MI WHERE MORE FAVORABLY-BACKED
LOW-LEVEL FLOW AHEAD OF SURFACE LOW IS EXPECTED.

FURTHER S ACROSS THE OZARKS...DEEP-LAYER SHEAR SHOULD BE WEAKER. 
HOWEVER...WITH MUCH GREATER INSTABILITY -- UP TO 2000 J/KG
MEAN-LAYER CAPE -- FORECAST ACROSS THIS REGION...CAPE / SHEAR
COMBINATION MAY STILL BE SUFFICIENT FOR A FEW ROTATING STORMS. 
THREAT FOR LARGE HAIL APPEARS TO EXIST WITHIN THIS REGION.

STORMS SHOULD CONTINUE SHIFTING EWD ACROSS THE UPPER LAKES REGION /
OH VALLEY THROUGH THE EVENING / OVERNIGHT...THOUGH DIURNAL
BOUNDARY-LAYER STABILIZATION SHOULD RESULT IN A SLOWLY-DIMINISHING
SEVERE THREAT THROUGH THE END OF THE PERIOD.

...KS / OK / ERN HALF OF TX...
WEAKENING COLD FRONT MOVING SWD ACROSS KS / INTO OK AT THE START OF
THE PERIOD IS FORECAST TO WEAKEN / DRIFT BACK NWD TOWARD KS THROUGH
THE AFTERNOON...WHILE DRYLINE SHOULD EXTEND SWD ACROSS CENTRAL OK /
CENTRAL TX.  NAM / NAMKF SHOW A SUBTLE SHORT-WAVE TROUGH MOVING
ACROSS THE REGION BEHIND MAIN TROUGH FURTHER E...WHICH COMBINED WITH
WEAK FORCING ALONG FRONT / DRYLINE MAY WEAKEN CAP SUFFICIENTLY TO
ALLOW A FEW STORMS TO DEVELOP.

THOUGH DEVELOPMENT OF DEEP CONVECTION REMAINS THE PRIMARY
QUESTION...MODERATELY-UNSTABLE AIRMASS IS ANTICIPATED ACROSS THIS
REGION AS DAYTIME HEATING COMBINED WITH LOW 60S DEWPOINTS BENEATH
STEEP LAPSE RATES ALOFT SHOULD RESULT IN 1500 TO 2500 J/KG
MEAN-LAYER CAPE.  WITH AROUND 30 KT MID-LEVEL NWLY FLOW
EXPECTED...CAPE / SHEAR COMBINATION APPEARS MORE THAN SUFFICIENT FOR
SUPERCELLS.  ATTM...WILL CARRY ONLY CONDITIONAL / 5% SEVERE
PROBABILITY.  HOWEVER...SHOULD STORM INITIATION BECOME MORE APPARENT
IN LATER OUTLOOKS...AN UPGRADE TO SLIGHT RISK WOULD LIKELY BE
REQUIRED -- MAINLY FOR THE THREAT FOR VERY LARGE HAIL.

...ID / THE GREAT BASIN REGION...
MARGINAL AIRMASS DESTABILIZATION IS FORECAST ACROSS THIS REGION AS
DIURNAL HEATING COMBINES WITH COOLING MID-LEVEL TEMPERATURES
SPREADING EWD IN CONJUNCTION WITH UPPER LOW.  THOUGH DEGREE OF
INSTABILITY SHOULD LIMIT ANY SEVERE THREAT...MODERATE DEEP-LAYER
WIND FIELD AND DIFFLUENT FLOW ALOFT MAY SUPPORT A FEW STRONGER /
ORGANIZED STORMS.  SHOULD THIS OCCUR...MARGINAL HAIL OR A
LOCALLY-DAMAGING GUST OR TWO WILL BE POSSIBLE.

..GOSS.. 05/09/2005

...NOTICE...
THE STATION RELATIVE POINTS IN THIS PRODUCT ARE NOW AVAILABLE
SEPARATELY UNDER THE WMO HEADINGS WUUS01 PTSDY1...
WUUS02 PTSDY2...WUUS03 PTSDY3.  THE INCLUSION OF POINTS
IN THIS DISCUSSION WILL BE DISCONTINUED AFTER THE 2005
CONVECTIVE SEASON.  A PUBLIC NOTIFICATION STATEMENT (PNS)
WILL PROVIDE DETAILS ON THE TRANSITION.