[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 160440
SWODY1
SPC AC 160439

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1139 PM CDT SUN MAY 15 2005

VALID 161200Z - 171200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 25 E
U31 15 N BYI 15 NNE IDA 35 ESE JAC 35 N RKS 25 ENE VEL 35 SW 4HV 50
SW SGU 25 NNW LAS 60 S TPH 25 E U31.

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 40 S
PHP 35 W PIR 40 SSW ABR BKX 20 NE YKN 35 WNW OFK 25 E HLC 40 WSW GAG
25 W CDS 20 W PVW 35 S DHT 35 WSW IML 40 S PHP.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 50 NNE MOT 20 NW FAR
50 NNE MSP 35 NNW RST 20 N FOD OMA 40 N CNK 30 SSE RSL 40 ENE GAG 10
ENE LTS 35 WNW TPL 30 SSW PSX ...CONT... 25 S MOB 25 SSW MGM CAE 25
ESE ECG ...CONT... 15 W ELP 25 NE ALM 50 S LVS 50 W RTN 65 S 4BL 35
ESE GCN 15 SSE EED 40 NW TRM PMD 50 ENE PRB SCK 40 SE RBL 55 SSW 4LW
25 S BKE 50 WNW CTB.

...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE GREAT
BASIN INTO THE NRN AND CNTRL ROCKIES...

...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF CNTRL/ERN SD
SWD INTO THE TX PNHDL...

...SYNOPSIS...
VIGOROUS...MID/UPPER-LEVEL TROUGH CURRENTLY APPROACHING THE PACIFIC
NW COAST IS FORECAST TO AMPLIFY THROUGH THE PERIOD AS IT TRANSLATES
EWD THROUGH THE PACIFIC NW AND GREAT BASIN...EVENTUALLY INTO THE NRN
AND CNTRL ROCKIES BY TUESDAY MORNING. THIS WILL RESULT IN DOWNSTREAM
BUILDING OF RIDGE OVER THE PLAINS WITH MID/UPPER LOW REMAINING
QUASI-STATIONARY OVER HUDSON BAY INTO THE ST. LAWRENCE VALLEY.

IN THE LOW-LEVELS...SURFACE LOW ATTENDANT TO PACIFIC NW SYSTEM
INITIALLY OVER ERN ORE/WRN ID AT 16/12Z WILL DEVELOP NEWD AND
CONSOLIDATE WITH BROADER LOW PRESSURE AREA OVER CNTRL MT TONIGHT.
MEANWHILE...STRONG...TRAILING PACIFIC COLD FRONT WILL PUSH EWD
THROUGH THE INTERMOUNTAIN W AND WILL LIKELY BE THE FOCUS FOR STRONG
TO SEVERE TSTM DEVELOPMENT THIS AFTERNOON AND TONIGHT. FARTHER
E...LEE TROUGH/DRYLINE WILL SHARPEN THROUGH THE DAY FROM WRN NEB SWD
INTO THE TX PNHDL WITH LITTLE EWD MOVEMENT OWING TO INCREASING
PRESSURE FALLS TO THE W. WEAK WARM FRONT OR QUASI-STATIONARY
BOUNDARY IS FORECAST TO MOVE LITTLE FROM IT/S INTERSECTION WITH LEE
TROUGH EWD INTO THE MIDDLE MO VALLEY.

...GREAT BASIN EWD INTO PORTIONS OF THE NRN AND CNTRL ROCKIES...
AS MENTIONED ABOVE...TSTMS ARE EXPECTED TO BECOME INCREASINGLY
WIDESPREAD LATER TODAY AS HEIGHT FALLS/DYNAMIC FORCING FOR ASCENT
AHEAD OF UPPER TROUGH OVERSPREAD FRONTAL ZONE. THOUGH LOW-LEVEL
MOISTURE WILL REMAIN QUITE LIMITED...THE DEVELOPMENT OF STEEP...LOW
TO MID-LEVEL LAPSE RATES AND STRONG AMBIENT WIND FIELDS SUGGEST THE
POTENTIAL FOR A FEW SEVERE TSTMS CAPABLE OF LARGE HAIL AND DAMAGING
WINDS.

FARTHER TO THE NE...INCREASINGLY DIFFLUENT UPPER PATTERN AHEAD OF
AMPLIFYING TROUGH MAY SUPPORT ADDITIONAL STORM DEVELOPMENT INTO
PORTIONS OF MT AND WY ALONG LEE TROUGH. GIVEN COMPARATIVELY WEAKER
MID-LEVEL LAPSE RATES AND VERTICAL SHEAR...SEVERE THREAT DOES NOT
APPEAR TO WARRANT A CATEGORICAL RISK OVER THIS AREA.

...CNTRL SD/NEB SWD INTO THE TX PNHDL...
PERSISTENT STEEP LAPSE RATES COUPLED WITH DEWPOINTS LARGELY IN THE
50S ARE EXPECTED TO CONTRIBUTE TO A MODERATELY UNSTABLE AIR MASS BY
AFTERNOON E OF LEE TROUGH/DRY LINE AND S OF WARM FRONT. PRIMARY
CONCERN IS WHETHER DEEP MOIST CONVECTION CAN INITIATE GIVEN: 1)
BUILDING HEIGHTS/STRENGTHENING CAP ACROSS INSTABILITY AXIS...AND 2)
ANTICIPATED WEAK LOW-LEVEL CONVERGENCE ALONG LEE TROUGH/DRYLINE.
INSPECTION OF DETERMINISTIC AND ENSEMBLE MODEL DATA INDICATE SOME
PRECIPITATION SIGNAL LATE THIS AFTERNOON/EARLY EVENING FROM S-CNTRL
SD/CNTRL NEB SWD INTO THE TX PNHDL. SHOULD STORMS DEVELOP...SLY
LOW-LEVEL FLOW BENEATH NWLY MID-LEVEL WINDS OF 20-25 KTS WILL RESULT
IN SUFFICIENT DEEP-LAYER SHEAR FOR ORGANIZED UPDRAFTS...POSSIBLY
EVEN A COUPLE OF SUPERCELLS CAPABLE OF DAMAGING WINDS AND LARGE
HAIL.

ADDITIONAL...MORE ELEVATED TSTMS MAY TEND TO DEVELOP TONIGHT NEWD
ACROSS PORTIONS OF ERN SD INTO SRN MN ALONG STRENGTHENING LLJ AXIS.
THOUGH INSTABILITY IS FORECAST TO REMAIN QUITE LIMITED...THE
STRONGEST STORMS MAY BE CAPABLE OF PRODUCING MARGINALLY SEVERE HAIL.


...SERN U.S...
A MODERATELY UNSTABLE AIR MASS IS FORECAST TO DEVELOP BY AFTERNOON
ALONG AND S OF STALLED FRONTAL BOUNDARY FROM SRN SC ACROSS SRN GA
INTO THE FL PNHDL WITH MLCAPES OF 1500-2000 J/KG. DESPITE RATHER
WEAK VERTICAL WIND SHEAR...DEGREE OF INSTABILITY MAY SUPPORT A FEW
VIGOROUS UPDRAFTS WITH THE POTENTIAL FOR MARGINAL HAIL AND/OR
LOCALLY STRONG WIND GUSTS.

..MEAD/BANACOS.. 05/16/2005

...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.