[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 131249
SWODY1
SPC AC 131247

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0747 AM CDT TUE JUL 13 2004

VALID 131300Z - 141200Z

THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 55 WNW
ERI 10 WNW YNG 30 SE UNI 20 WSW LEX 10 E EVV 25 NW SLO 40 W MLI 45
NE ALO 30 W GRB 10 N MBL 55 NNE MTC.

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 25 N
ROC 15 S PSB 40 W SHD 35 ESE TRI 10 ESE CHA 20 NNW MKL 20 NNW POF 15
SSE SZL 40 SW FNB 30 NE MCK 45 ESE CYS 15 E LAR 25 NNW CPR 35 SE SHR
30 SE 4BQ 25 S PHP 35 W YKN SPW 40 WNW EAU 75 N IWD.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 10 N GLS 35 SW LFK 25
S TYR 40 SE PRX 45 NE TXK 15 N PBF 15 SSW UNO 30 NNW CNU 15 WSW SLN
50 WNW GLD 25 WSW LIC 25 E LVS ROW 25 WNW INK 15 SSW P07 ...CONT...
10 SW IPL IGM 30 SSE SGU 10 NNE MLF 35 NNW PIH 25 S 27U 30 E BKE 60
SSW RDM 30 SSE EUG 35 WNW BLI ...CONT... 65 NNW GGW 35 N PIR 25 NE
MHE 25 NNW OTG 25 NE RWF 25 ESE BRD 35 NW HIB 40 WNW INL ...CONT...
60 W 3B1 25 NE PSM.

...THERE IS A MDT RISK OF SVR TSTMS OVER EXTREME ERN IA...SRN
WI...SRN LOWER MI...MUCH OF IL...IND AND OH...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER OH/TN VLYS INTO
THE CNTRL-NRN HIGH PLAINS...

...SYNOPSIS...
VIGOROUS MIDLEVEL SHORTWAVE TROUGH MOVING INTO NRN MN ATTM IS
EXPECTED TO DIG SEWD ACROSS THE GREAT LAKES REGION AND UPPER MIDWEST
THROUGH TONIGHT.  ASSOCIATED COLD FRONT WILL SWEEP RAPIDLY
SEWD...REACHING THE UPPER OH VLY TO MID MS VLY BY EARLY WEDNESDAY. 
TAIL END OF THE FRONT WILL MOVE SLOWER...AND EXTEND NWWD INTO THE
NRN HIGH PLAINS.  

UPPER ANTICYCLONE CENTERED VCNTY CO WILL REMAIN IN PLACE THROUGH THE
PERIOD WITH MIDLEVEL DISTURBANCES ROTATING ALONG THE PERIPHERY OF
THE HIGH INTO THE PAC NW.  INVERTED TROUGH/CLOSED LOW NEAR THE TX
BIG BEND WILL MOVE WWD INTO CHIHUAHUA...SONORA AND SRN AZ BY
TONIGHT.

...UPPER MS VLY SEWD TO THE OH/TN VLYS...
RATHER ACTIVE SEVERE WEATHER DAY ANTICIPATED ACROSS THE REGION WITH
PARTICULARLY DAMAGING WIND GUSTS AND GIANT HAIL ACROSS THE MDT RISK
AREA.

AS H5 HEIGHT FALLS OF 60-90 METERS BEGINS TO ACCELERATE SEWD...
TSTMS ARE EXPECTED TO INITIATE ACROSS THE UPPER MS VLY AND UPPER
GREAT LAKES LATE THIS MORNING. AIR MASS DOWNSTREAM WILL BECOME VERY
UNSTABLE THROUGHOUT THE DAY AS 70-75F SURFACE DEW POINTS COINCIDE
WITH ERN EDGE OF STEEP MIDLEVEL LAPSE RATES.  THUS... TSTMS ARE APT
TO RAPIDLY ORGANIZE AND BECOME SEVERE. WHILE HODOGRAPHS ARE MORE
INDICATIVE OF BOW ECHOS AS THE FLOW BECOMES NWLY THROUGH A DEEP
LAYER...SUFFICIENT VERTICAL SHEAR WILL EXIST FOR EMBEDDED
SUPERCELLS.  INITIAL TSTMS MAY PRODUCE HAILSTONES GREATER THAN 2
INCHES...PRIMARILY FROM ERN IA/SRN WI INTO CNTRL/ NRN IL. 
ADDITIONALLY...A TORNADO OR TWO WILL BE POSSIBLE...MAINLY ALONG SWRN
PARTS OF THE MDT RISK WHERE LOW LEVEL SRH WILL BE HIGHER AND
SMALLER-SCALE ROTATING COMMA HEADS. 

ACTIVITY IS LIKELY TO CONGEAL QUICKLY INTO A FORWARD PROPAGATING MCS
WITH WIDESPREAD WIND DAMAGE EXPECTED IN A SWATH FROM SRN WI...ERN IA
ESEWD ACROSS THE UPPER MIDWEST AND OH VLY OVERNIGHT.  12Z SOUNDINGS
ACROSS THE MDT RISK AREA SHOW A LARGE DEGREE OF DRY AIR IN THE
CONVECTIVE GENERATING LAYER AND THIS MAY AUGMENT WIND PRODUCTION. 
LEADING EDGE OF THE MCS SHOULD APPROACH THE UPPER OH VLY BY THE END
OF THE PERIOD.

FARTHER SW...12Z OMAHA SOUNDING EXHIBITED A VERY WARM LAYER H85-H7
WITH H7 TEMPERATURE OF 14C.  THIS CAP/WARM LAYER MAY INHIBIT DEEP
MOIST CONVECTION FROM FORMING ALONG THE SWD MOVING COLD FRONT ACROSS
MO AND WRN IA. BUT...GIVEN A STORM...POTENTIAL WILL EXIST FOR VERY
LARGE HAIL AND DAMAGING WINDS. WILL MAINTAIN A CONDITIONAL SLIGHT
RISK.

...NRN HIGH PLAINS INTO SWRN SD AND SWRN NEB...
A WEAK MIDLEVEL IMPULSE WAS NOTED ON VAPOR IMAGERY VCNTY NRN/CNTRL
UT AND IS EXPECTED TO ROTATE NEWD THEN EWD THROUGH WY AND INTO NEB
BY LATE TONIGHT.  TSTMS ARE APT TO INCREASE ON THE WY/MT HIGHER
TERRAIN THIS AFTERNOON AND THEN ONTO THE HIGH PLAINS TONIGHT.  SELY
BOUNDARY LAYER FLOW SHOULD MAINTAIN UPPER 40S-LOWER 50S DEW POINTS
TODAY BENEATH 8.5 C/KM MID-TROPOSPHERIC LAPSE RATES... CONTRIBUTING
TO 1000-1500 J/KG MLCAPES FROM NEB PNHDL/ERN WY/SWRN SD AND NWWD TO
PARTS OF CNTRL/SRN MT. REGION WILL LIE ALONG SRN PERIPHERY OF THE
STRONGER NWLY FLOW AND SUFFICIENT VERTICAL SHEAR WILL EXIST FOR A
FEW STORMS TO GIVE LARGE HAIL AND DAMAGING WINDS.  LLJ DEVELOPMENT
DURING THE EVENING MAY SUSTAIN ONE OR MORE TSTM CLUSTERS INTO SRN SD
OR NEB OVERNIGHT...THOUGH THE SEVERE THREAT MAY TREND TOWARD ISOLD
LARGE HAILSTONES GIVEN MORE ELEVATED NATURE TO THE STORMS.  

...DESERT SW...
DIFFICULT TO DETERMINE MAGNITUDE OF POSSIBLE GULF SURGE THIS
MORNING...THOUGH NAME INSTRUMENT PLATFORMS IN/NEAR THE GULF OF CA DO
SHOW AN INCREASE IN PWAT AND SURFACE PRESSURE SINCE 06Z.  ANY SURGE
WILL CONTINUE TO SPREAD NWD INTO SRN AZ INTO EARLY WEDNESDAY...
MOISTENING THE BOUNDARY LAYER. EARLY MORNING VSBL IMAGERY SUGGESTS
THAT AIR MASS WILL DESTABILIZE RAPIDLY TODAY AND INCREASING UPPER
DIVERGENCE AHEAD OF THE TX BIG BEND INVERTED TROUGH/UPPER LOW WILL
ENCOURAGE TSTMS TO DEVELOP OVER THE HIGHER TERRAIN.  TSTMS MAY
CLUSTER AND PROPAGATE INTO THE VLYS OF SCNTRL AZ THIS EVENING. 
GIVEN INVERTED-V LOW LEVEL THERMODYNAMIC STRUCTURES...ISOLD DAMAGING
WINDS WILL BE POSSIBLE.  MIDLEVEL ELY FLOW IS FORECAST TO BE AOB 20
KTS...BUT IF HIGHER SPEEDS EXIST ON N SIDE OF THE UPPER LOW LATER
TODAY...POTENTIAL FOR HIGHER COVERAGE WIND DAMAGE MAY OCCUR.

..RACY/GUYER.. 07/13/2004

...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.