[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 031244
SWODY1
SPC AC 031242

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0742 AM CDT TUE AUG 03 2004

VALID 031300Z - 041200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 65 NNE
OLF 10 NE DIK 20 SW ABR 35 ENE MKT 35 E MSN 30 WSW SBN 15 SE DNV 10
SE ALN 35 ENE SZL TOP 35 N RSL 35 S MCK 35 WSW IML 30 SSE BFF 45 WSW
GCC 25 E DLN 20 SSW MSO 45 N MSO 65 NNE FCA.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 60 NNW MOT 20 NW JMS
AXN 35 S CWA 35 SSW MBL 35 N MBS 70 ENE OSC ...CONT... 55 WNW MFE 20
NW VCT 25 ESE CLL 40 N LFT 20 E JAN 15 ENE RMG 30 SW BLF 40 WSW BKW
30 W LOZ 35 SW CKV 30 NW DYR 55 NW POF 15 SSW VIH 50 N SGF 35 NE OKC
45 N CDS 25 SSE LBB 40 SW P07 ...CONT... 65 SW GBN 20 SSW PRC 20 NE
P38 60 NW ENV 30 N TWF 20 NE SUN 50 N SUN 80 S S80 20 NNW BKE 45 W
PUW 40 NNE EPH 15 N EAT 10 ESE YKM 40 SSE RDM 70 SSW RDM 35 SE EUG
50 NNE PDX 30 ENE SEA 25 NE BLI.

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN ROCKIES INTO THE
UPPER MIDWEST...

...SYNOPSIS...
ACTIVE WAVE TRAIN IS FORECAST BETWEEN OMEGA-TYPE BLOCKING PATTERN
EVOLVING ACROSS CANADA AND DOMINANT MID-LEVEL RIDGE OVER THE SRN
ROCKIES INTO SRN PLAINS. SEVERAL VORTICITY MAXIMA /OBSERVED ON WATER
VAPOR IMAGERY OVER THE NRN/CNTRL ROCKIES/ WILL TRANSLATE EWD THROUGH
THE MEAN RIDGE POSITION WITH RESULTANT DOWNSTREAM HEIGHT FALLS
OCCURRING ACROSS THE WRN GREAT LAKES INTO MID MS VALLEY. AT THE
SURFACE...IT APPEARS THAT PRIMARY FOCUS FOR SEVERE TSTM DEVELOPMENT
THIS PERIOD WILL BE QUASI-STATIONARY BOUNDARY EXTENDING FROM THE NRN
ROCKIES SEWD TO LOW PRESSURE OVER CNTRL NEB AND THEN EWD INTO THE
UPPER MIDWEST.

...NRN/CNTRL PLAINS INTO THE MID MS VALLEY...
STEEP LAPSE RATE PLUME /OBSERVED IN 12Z OMA/DVN SOUNDINGS/...
DIABATIC HEATING AND MOIST LOW-LEVEL AIRMASS /PRESENT FROM THE SRN
LOW PLAINS INTO THE MID MO VALLEY/ WILL CONTRIBUTE TO AFTERNOON
MLCAPES APPROACHING 2000-3000 J/KG ALONG AND S OF AFOREMENTIONED
QUASI-STATIONARY BOUNDARY. MCS IN PROGRESS THIS MORNING OVER CNTRL
SD SHOULD CONTINUE TO PROPAGATE SEWD ALONG COOL SIDE OF
BOUNDARY...BEING FEED BY DESTABILIZING AIRMASS TO THE S ACROSS ERN
NEB INTO IA. IF COMPLEX CAN PERSIST INTO THE AFTERNOON...
DEEPENING/WARMING OF INFLOW BOUNDARY-LAYER SHOULD PROMOTE
INCREASINGLY STRONG DOWNDRAFTS AND THE POTENTIAL FOR WIDESPREAD
DAMAGING WIND POTENTIAL.

ADDITIONAL STORMS WILL LIKELY DEVELOP TO THE W ACROSS PORTIONS OF SD
AND NEB LATER TODAY AS SHORTWAVE TROUGHS /CURRENTLY OVER S-CNTRL MT
INTO WRN WY AND OVER CNTRL CO/ TRANSLATE EWD INTO DEVELOPING
INSTABILITY AXIS.  MODERATE TO STRONG INSTABILITY COUPLED WITH
MODEST DEEP-LAYER SHEAR OF 30-40KTS SUGGESTS THE POTENTIAL FOR
ORGANIZED SEVERE STORMS /INCLUDING SUPERCELLS/ WITH LARGE HAIL AND
DAMAGING WINDS BEING THE PRIMARY SEVERE WEATHER THREATS. UPSCALE
EVOLUTION INTO AN MCS OR SEVERAL STORM CLUSTERS WILL BE POSSIBLE
OVERNIGHT...ESPECIALLY ALONG NOSE OF LLJ AXIS AND AHEAD OF MIGRATORY
SURFACE LOW FROM CNTRL/ERN NEB INTO IA.

CLUSTER OF STORMS OVER SERN IA/NERN MO MAY POSE A DAMAGING WIND
THREAT AS IT PROGRESSES SEWD ALONG WEAK SECONDARY BOUNDARY EXTENDING
FROM N-CNTRL MO INTO SRN IL. WIND SHEAR IS EXPECTED TO REMAIN
RELATIVELY WEAK...HOWEVER MODERATE INSTABILITY SHOULD SUPPORT
VIGOROUS UPDRAFT DEVELOPMENT ALONG LEADING EDGE OF COLD POOL.

...NRN ROCKIES...
VIGOROUS VORTICITY CENTER /CURRENTLY OVER NERN ORE/ WILL LIFT NEWD
ACROSS THE ID PNHDL/FAR WRN MT AND INTO SRN ALBERTA TODAY.
EXTRAPOLATION PLACES CORRESPONDING REGION OF STRONGEST LARGE-SCALE
ASCENT INTO CANADA PRIOR TO PEAK HEATING. LATEST MODEL GUIDANCE DOES
SUGGEST THAT PERSISTENT LOW-LEVEL UPSLOPE COMPONENT ALONG TRAILING
EDGE OF THIS FORCING MAY BE SUFFICIENT TO INITIATE STORMS LATER
TODAY ACROSS WRN MT WITHIN WEAKLY TO MODERATELY UNSTABLE AIRMASS
WITH MLCAPES OF 500-1500 J/KG. PRESENCE OF STEEP LAPSE RATES AND
MODEST SHEAR SHOULD SUPPORT A FEW ORGANIZED STORMS CAPABLE OF
DAMAGING WINDS OR LARGE HAIL.

...NC OUTER BANKS...
PER 11Z TPC HURRICANE FORECAST/ADVISORY...CENTER OF ALEX IS EXPECTED
PASS VERY NEAR THE OUTER BANKS TODAY...PRIOR TO ACCELERATING NEWD
INTO THE ATLANTIC. THIS TRACK SUGGESTS MOST FAVORABLE REGION FOR
TROPICAL CYCLONE-SPAWNED TORNADOES WILL LIKELY REMAIN OFF THE COAST.
NONETHELESS...RUC FORECAST SOUNDINGS VALID FOR MID TO LATE MORNING
INDICATE SUFFICIENT SHEAR/INSTABILITY /I.E. 100-150 M2/S2 0-3KM SRH
AND 500-1000 J/KG MLCAPES/ TO SUPPORT ISOLATED TORNADOES WITH
CONVECTIVE BANDS WRAPPING WWD AROUND THE HURRICANE CENTER.

FOR ADDITIONAL SHORT-TERM GUIDANCE...PLEASE SEE MCD 1849.

...NORTHEASTERN STATES...
LOOSELY ORGANIZED BAND OF STORMS IS IN PROGRESS THIS MORNING ALONG
AND JUST S/E OF ST. LAWRENCE VALLEY AHEAD OF SHORTWAVE TROUGH AND
ASSOCIATED SURFACE FRONT PROGRESSING EWD ACROSS SERN ONTARIO. THOUGH
MID-LEVEL LAPSE RATES ARE EXPECTED TO REMAIN WEAK AND NEAR MOIST
ADIABATIC...DAYTIME HEATING COUPLED WITH SURFACE DEWPOINTS GENERALLY
IN THE 60S SHOULD CONTRIBUTE TO AIRMASS DESTABILIZATION AHEAD OF
FRONT AND ANY ONGOING STORMS LATER TODAY. UNIDIRECTIONAL WIND FIELDS
AND MODEST DEEP-LAYER SHEAR OF 25-30KTS MAY SUPPORT SOME POTENTIAL
FOR ORGANIZED LINE SEGMENTS/BOWING STRUCTURES CAPABLE OF MARGINALLY
SEVERE WIND GUSTS. OVERALL SEVERE WEATHER THREAT WILL LIKELY BE
LIMITED BY THE LACK OF STRONGER INSTABILITY.

..MEAD.. 08/03/2004

...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.