[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 062123
SWODY1
SPC AC 062121

DAY 1 CONVECTIVE OUTLOOK AMEND 1
NWS STORM PREDICTION CENTER NORMAN OK
0421 PM CDT FRI AUG 06 2004

VALID 062130Z - 071200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 70 NE
MOT 50 W DVL 60 WNW JMS 40 NE MBG 30 NE PIR 35 W VTN 30 NW MHN 40 NW
IML 20 W SNY 20 NNW WRL 15 NNE WEY 40 NNE 27U 20 SSW S80 20 WNW LWS
10 SSE GEG 35 NE 63S.

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 50 ENE
HOB 20 NE CVS 15 W DHT 60 NNE AMA 45 SE AMA 45 SE LBB 55 E HOB 50
ENE HOB.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 ESE YUM 15 SSE EED
40 SW SGU 40 NW CDC 35 ENE U24 20 WNW IDA 35 S 27U 75 E BKE 60 N BNO
45 NNW RDM 35 S AST ...CONT... 45 NW ELO 40 ESE BRD 35 E FRM 35 SSW
SPW 20 NE CNK 40 S PNC 25 NNW ACT 50 ENE CLL 20 W 7R4 30 NW BVE
...CONT... 25 WNW PFN 30 NNE SSI.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NRN HIGH PLAINS AND
NRN ROCKIES...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF W TX...

AMENDED TO ADD SLGT RISK FOR PARTS OF TX PNHDL/W TX

...PARTS OF W TX...
STRONG-SEVERE TSTMS CONTINUE TO DEVELOP ALONG BOUNDARY ORIENTED N-S
ACROSS W TX.  SBCAPES TO 4000 J/KG AND ENHANCED DEEP LAYER SHEAR
OWING TO STRONGLY VEERING WIND PROFILES WILL CONTRIBUTE TO THE
POTENTIAL FOR SUPERCELLS.  LARGE HAIL AND DAMAGING WINDS WILL BE THE
PRIMARY THREATS...THOUGH A BRIEF ISOLD SPIN-UP WILL BE POSSIBLE.

***REMAINDER OF THE FORECAST UNCHANGED FROM 2000 UTC***


...NRN ROCKIES/NRN HIGH PLAINS...
SURFACE OBS AND 18Z GREAT FALLS SOUNDING SHOW THAT BOUNDARY LAYER
DEW POINTS ARE DRIER THAN RECENT DAYS ACROSS THE NRN ROCKIES AREA
WITH DEW POINTS GENERALLY IN THE MID 40S.  AS A RESULT...AIR MASS IS
NOT AS UNSTABLE AS ON THURSDAY WITH PRIMARY INSTABILITY AXIS
SITUATED FROM SERN MT/NERN WY INTO WRN SD.

WATER VAPOR IMAGERY HAS INDICATED A WEAKENING OF THE MIDLEVEL
SHORTWAVE TROUGH EJECTING NEWD THROUGH WRN ID RECENTLY.  THIS
IMPULSE WILL MOVE NEWD INTO CNTRL MT/NRN WY THROUGH TONIGHT. CBS ARE
DEVELOPING OVER THE SWRN MT/ID MOUNTAINS AND A FEW TSTMS ARE
EXPECTED TO EVOLVE LATER THIS AFTERNOON AND MOVE NEWD INTO WRN/CNTRL
MT.  GIVEN THE HIGH SHEAR/LOW INSTABILITY ENVIRONMENT...THESE TSTMS
WILL LIKELY BE HIGH BASED GIVING SEVERE WIND GUSTS.  VERTICAL SHEAR
WILL BE SUFFICIENT FOR SUPERCELLS AS WELL AND LARGE HAIL COULD
OCCUR.

FARTHER EAST...TSTMS DEVELOPING ON THE WY MOUNTAINS AND BLACK HILLS
WILL LIKELY GROW UPSCALE AND MOVE INTO THE LOWER TERRAIN OF ERN
WY...SCNTRL/SERN MT...WRN NEB PNHDL AND WRN SD THROUGH THE
AFTERNOON/EVENING.  LATEST OBJECTIVE ANALYSIS SUGGEST THAT THE DEEP
LAYER SHEAR WAS AROUND 35 KTS AND A SUPERCELL OR TWO IS POSSIBLE
GIVEN AROUND 1500 J/KG MLCAPE. LARGE HAIL AND SEVERE WIND GUSTS
WOULD BE THE PRIMARY THREATS.

ACROSS NERN MT AND WRN ND...SLGT RISK/PROBABILITIES HAVE BEEN
MAINTAINED.  IMPULSE NOW MOVING INTO THE ERN DAKOTAS APPEARS TO BE
INFLUENCING THE DIURNAL WIND FIELDS...MAINTAINING A VEERED WLY FLOW
IN THE BOUNDARY LAYER. MOREOVER...SUBSIDENCE APPEARS TO BE
DOMINATING THE AREA ATTM.  TSTMS MAY APPROACH FROM SCNTRL/SERN MT
LATER TONIGHT...AND COULD DEVELOP ALONG THE LEE-TROUGH ACROSS CNTRL
ND/NWRN SD LATER THIS AFTERNOON AS THE DOWNSTREAM IMPULSE MOVES AWAY
FROM THE AREA. GIVEN A STORM...LARGE HAIL OR DAMAGING WINDS MAY
OCCUR. THUS...WILL MAINTAIN A CONDITIONAL SLGT RISK.

...NRN PLAINS/RED RVR VLY AREA...
ELEVATED TSTMS CONTINUE TO MOVE/DEVELOP ACROSS THE ERN ND AREA IN
ASSOCIATION WITH A MIDLEVEL SHORTWAVE TROUGH.  LOW LEVEL
TRAJECTORIES SUGGEST THAT PARCELS FEEDING THE TSTMS RESIDE IN A
RESERVOIR OF 1500 J/KG MUCAPES.  EFFECTIVE DEEP LAYER SHEAR WAS IN
THE 25-30 KT RANGE AND SUGGEST THE STORMS WILL NOT BE PARTICULARLY
LONG-LIVED.  NONETHELESS...ISOLD MARGINALLY SEVERE HAIL MAY OCCUR
WITH THE STRONGER UPDRAFTS.

...DESERT SW...
MOST VIGOROUS TSTM DEVELOPMENT THROUGH EARLY AFTERNOON HAS BEEN ON
NRN PERIPHERY OF RESIDUAL CLOUD CANOPY ACROSS NRN/NWRN AZ.  18Z
FLAGSTAFF SOUNDING SUGGESTS THAT A FEW LONGER LIVED TSTMS ARE
POSSIBLE GIVEN THE 50-55 KT HIGH LEVEL FLOW.  THE STRONGER STORMS
MAY PRODUCE HAIL APPROACHING SEVERE LIMITS.

A LATER START TO THE TSTM DEVELOPMENT IS OCCURRING ACROSS SERN AZ
AND SWRN NM.  THIS HAS ALLOWED THE BOUNDARY LAYER TO WARM
CONSIDERABLY AND 18Z TUCSON SOUNDING USING A 91/61 PARCEL EXHIBITED
SBCAPES AROUND 2000 J/KG AND AROUND 1.5 INCHES OF PWAT.  THE
STEERING FLOW IS NOT PARTICULARLY STRONG AND HEAVY RAINFALL WILL BE
THE PRIMARY THREAT.  BUT...GIVEN INVERTED-V LOW LEVEL
PROFILES...ISOLD MICROBURSTS WILL BE LIKELY.

...CNTRL/SRN FL...
COLD FRONT/PRE-FRONTAL TROUGHS CONTINUE TO SETTLE SWD ACROSS FL. 
GIVEN SLIGHTLY DRIER AIR ADVECTING IN ALOFT...ISOLD TSTMS MAY
PRODUCE DAMAGING WIND GUSTS.

..RACY.. 08/06/2004

...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.