[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 220528
SWODY1
SPC AC 220526

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1226 AM CDT SUN AUG 22 2004

VALID 221200Z - 231200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 50 W
4BQ 45 SW BIL 30 SSE HLN 30 NNW HLN 30 NW GTF 20 WSW HVR 40 NW GGW
20 NE GDV 55 NW REJ 50 W 4BQ.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 60 WNW MRF 55 ESE ALM
65 SSW GNT 30 WSW CDC 40 S TVL 50 WNW SVE 30 SSW MHS 55 ESE EKA 15
ENE EKA 40 ENE CEC 35 ENE BLI ...CONT... 65 NNW DVL 45 NNE ATY 40
NNE RWF 55 ENE ELO.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 35 SSE MTC 30 N BRL
45 SW UIN 20 ESE BLV 40 NNE MKL 15 ENE MSL 35 NNW HSE ...CONT... 20
WNW EFK 20 SW SYR 25 NW JHW.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF CENTRAL AND ERN
MT...

...SYNOPSIS...
SURFACE BOUNDARY AT THE LEADING EDGE OF COOL AIR ASSOCIATED WITH
CANADIAN HIGH PRESSURE IS FORECAST TO BE MOVING SEWD ACROSS THE NRN
PLAINS TOWARD THE UPPER MS VALLEY...AND SWWD TOWARD THE NRN ROCKIES
AT THE START OF THE PERIOD.  THE FRONT WILL CONTINUE EWD ACROSS THE
GREAT LAKES THROUGH THE PERIOD AS SURFACE LOW INITIALLY FORECAST
NEAR THE MN ARROWHEAD DEEPENS AND MOVES RAPIDLY NEWD INTO CENTRAL
QUEBEC.  MEANWHILE...THE FRONT WILL MOVE ONLY SLOWLY SWD ACROSS NEB
/ IA...AND SHOULD LINGER ACROSS MT THROUGH THE AFTERNOON BEFORE
SHIFTING EWD AS A WARM FRONT THROUGH THE SECOND HALF OF THE PERIOD.

ALOFT...STRONG SHORT-WAVE TROUGH ASSOCIATED WITH AFOREMENTIONED
SURFACE LOW IS INITIALLY FORECAST ACROSS S CENTRAL QUEBEC / THE WRN
UPPER LAKES REGION.  THIS FEATURE WILL ALSO SHIFT RAPIDLY ENEWD INTO
QUEBEC BY THE END OF THE PERIOD.  MEANWHILE...A SECOND STRONG
SHORT-WAVE TROUGH INITIALLY OVER THE PAC NW WILL MOVE EWD ACROSS ID
AND INTO MT / WY WITH TIME WHILE TAKING ON A SLIGHT NEGATIVE TILT. 
FURTHER S -- ACROSS THE SRN 2/3 OF THE COUNTRY...A GENERALLY WEAK
UPPER FLOW PATTERN IS FORECAST.

...CENTRAL AND ERN MT...
QG FORCING IS FORECAST TO INCREASE DURING THE AFTERNOON / EVENING
ACROSS MT AS UPPER TROUGH SHIFTS EWD AND SELY LOW-LEVEL JET
INCREASES IN RESPONSE. HOWEVER...LIMITED LOW-LEVEL MOISTURE -- AND
THUS ONLY MARGINAL DESTABILIZATION -- IS FORECAST ACROSS THIS REGION
THROUGH THE AFTERNOON. 

EXPECT SCATTERED TO ISOLATED / HIGH-BASED STORMS TO DEVELOP OVER /
MOVE OFF THE HIGHER TERRAIN OF WRN MT DURING THE MID TO LATE
AFTERNOON.  WITH 40 TO 50 KT SWLY MID-LEVEL FLOW...SHEAR WILL
SUPPORT ROTATING UPDRAFTS...THOUGH LIMITED MOISTURE / INSTABILITY
AND HIGH CLOUD BASES SUGGEST THAT SEVERE THREAT SHOULD BE LIMITED TO
LOCALLY DAMAGING WINDS WITH A FEW OF THE STRONGER STORMS.  

BY EARLY EVENING...LOW-LEVEL JET IS FORECAST TO INCREASE TO AROUND
45 KT FROM THE SOUTHEAST ACROSS ERN MT.  RESULTING WARM ADVECTION
BENEATH INCREASINGLY DIFFLUENT FLOW ALOFT WILL SUPPORT A
CONTINUATION OF CONVECTION...WHICH SHOULD EVENTUALLY SPREAD INTO ND.
 

DESPITE INCREASINGLY STRONG / VEERING DEEP-LAYER WIND FIELD...SEVERE
THREAT SHOULD SLOWLY DECREASE AFTER SUNSET AS LOW-LEVEL
STABILIZATION DECREASES THE POTENTIAL FOR DAMAGING WINDS...AND
MARGINAL INSTABILITY ABOVE STABILIZING BOUNDARY LAYER LIMITS ANY
HAIL POTENTIAL. 

...WI / SRN MN / IA AREA...
ELEVATED STORMS WILL LIKELY BE ONGOING ACROSS THIS REGION IN WARM
ADVECTION REGIME ASSOCIATED WITH UPPER SHORT-WAVE TROUGH.  

THIS TROUGH IS FORECAST TO SHIFT EWD INTO THE ERN UPPER LAKES / ERN
ONTARIO REGION BY AFTERNOON...AND THUS EXPECT WEAK LARGE-SCALE
SUBSIDENCE TO DEVELOP OVER THE UPPER MS VALLEY REGION. 
NONETHELESS...LIMITED INSTABILITY AND WEAK LOW-LEVEL CONVERGENCE
ALONG SEWD-MOVING FRONT MAY SUPPORT ISOLATED STORM DEVELOPMENT.

STRONGEST MID-LEVEL NWLYS SHOULD REMAIN NE OF ANY APPRECIABLE
INSTABILITY...BUT SUFFICIENT FLOW SHOULD EXTEND SWWD ACROSS THIS
REGION TO SUPPORT A LIMITED THREAT FOR ORGANIZED UPDRAFTS.  ANY WIND
/ HAIL THREAT SHOULD DECREASE AFTER SUNSET AS LOW-LEVEL AIRMASS
STABILIZES.

...HIGH PLAINS...
MODERATE INSTABILITY IS FORECAST TO DEVELOP ONCE AGAIN ACROSS THE
HIGH PLAINS...WITHIN WEAKLY-SHEARED ENVIRONMENT.  SCATTERED TO
ISOLATED STORMS WILL LIKELY DEVELOP OVER THE HIGH PLAINS ALONG LEE
TROUGH BY AFTERNOON...AND PERHAPS ACROSS REMNANT OUTFLOW ACROSS
CENTRAL / NRN TX.  HOWEVER...GENERALLY WEAK DEEP-LAYER WIND FIELD
SUGGESTS MAINLY DISORGANIZED PULSE-TYPE CONVECTION AND ASSOCIATED
THREAT FOR LOCALLY GUSTY WINDS / HAIL WITH A FEW STRONGER STORMS.  

AS LOW-LEVEL JET DEVELOPS DURING THE EVENING...SOMEWHAT MORE
FAVORABLE SHEAR MAY SUPPORT MULTICELL OR PERHAPS WEAKLY-ROTATING
STORMS...AND THUS A PERIOD OF SOMEWHAT GREATER SEVERE POTENTIAL. 
HOWEVER...STABILIZING LOW-LEVEL AIRMASS AND LACK OF UPPER SUPPORT
SUGGEST THAT SEVERE THREAT SHOULD SLOWLY TAPER OFF OVERNIGHT.

..GOSS.. 08/22/2004

...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.