[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 211256
SWODY1
SPC AC 211253

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0753 AM CDT SAT AUG 21 2004

VALID 211300Z - 221200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 30 SSE
OAJ 45 NE RWI NHK 25 SE DOV.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 W ANJ 30 W OSH 30
NE ALO 25 WNW DSM 45 WSW YKN 40 SE PHP 15 ESE REJ 70 WSW DIK 35 NNW
SHR 45 NW RWL 25 SE FCL 20 SSE GLD 55 SW HLC 15 SW DDC 60 N CDS 35 S
LTS 30 WSW ADM 30 NNE HOT 15 SE MKL 35 NNW JKL 10 W BFD 25 SSE EFK
30 S HUL ...CONT... 20 ESE PSX 15 SE DRT ...CONT... 65 SSE ELP 45 E
DMN 35 ESE PRC 50 WSW LAS 55 SE TVL 60 SW SVE 30 SSW ONP.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS EXTREME ERN PARTS OF
NC/VA INTO DELMARVA...

...MID-ATLANTIC REGION...
EARLY VSBL SATELLITE PICTURES SUGGEST THAT THERE WILL BE POCKETS OF
HEATING THIS MORNING FROM THE CAROLINAS NWD TO DELMARVA/SRN NJ. 
MESOANALYSIS INDICATES THAT RICH BOUNDARY LAYER MOISTURE EXISTS WITH
SURFACE DEW POINTS IN THE LOW-MID 70S. GIVEN HEATING...
DESTABILIZATION WILL OCCUR...BUT 12Z SOUNDINGS SAMPLED POOR LAPSE
RATES INLAND...LIKELY A NEGATIVE FACTOR FOR WIDESPREAD SEVERE TSTMS.
 HOWEVER...MOREHEAD CITY AND WALLOPS ISLAND SOUNDINGS INDICATE
SLIGHTLY STEEPER MIDLEVEL LAPSE RATES ALONG THE COAST. 

WATER VAPOR IMAGERY SHOWS A STRONG MIDLEVEL SHORTWAVE TROUGH MOVING
RAPIDLY THROUGH THE CNTRL APPALACHIANS AND IT IS EXTRAPOLATED TO BE
OVER THE MID-ATLANTIC REGION DURING PEAK HEATING.  THUS...TSTMS
CURRENTLY ALONG THE CREST OF THE APPALACHIANS/COLD FRONT ARE LIKELY
TO INCREASE IN NUMBER AND MOVE EWD THROUGH THIS AFTERNOON.  GIVEN
THE INCREASING WSWLY UNIDIRECTIONAL FLOW THROUGH THE LOWEST 6KM AND
SLIGHTLY STEEPER LAPSE RATES ALONG THE COAST...HAVE OPTED TO ADD A
SMALL SLGT RISK FROM NERN NC NWD THROUGH SERN VA INTO THE DELMARVA
AREA FOR POSSIBLE DAMAGING WIND GUSTS WITH THE STRONGER STORMS.  

...CNTRL/SRN FL...
12Z SOUNDINGS FROM MIAMI AND TAMPA EXHIBIT PRECIPITABLE WATER VALUES
AOA 2 INCHES WITH INDICATIONS OF LESS SATURATED AIR CENTERED NEAR
H7.  H5 TEMPERATURES OF MINUS 8C COUPLED WITH THE HIGH PRECIPITABLE
WATER VALUES WILL LEAD TO A VERY UNSTABLE ENVIRONMENT TODAY WITH
SBCAPES 3500-4000 J/KG AND LIS TO MINUS 10C.  DEEP MOIST CONVECTION
SHOULD FAVOR SEABREEZE/OUTFLOW COLLISIONS AND THE THERMODYNAMIC
SET-UP APPEARS VERY FAVORABLE FOR ISOLD WET MICROBURSTS...HAIL AND
PERHAPS A BRIEF TORNADO/ WATERSPOUT.

...SRN/CNTRL HIGH PLAINS...
LONG-LIVED TSTM CLUSTER MOVING THROUGH THE TX PNHDL THIS MORNING
SEEMS TO BE TIED WITH A WEAK MIDLEVEL JET STREAK/DARKENING MOVING
THROUGH SRN NM.  THE TSTMS AND ASSOCIATED FEATURE WILL BE ENTERING A
MORE CONFLUENT MID/UPPER FLOW REGIME THROUGH THE DAY AND SHOULD
WEAKEN.

OTHERWISE...LOW-LEVEL FEATURES ARE APT TO BECOME ILL-DEFINED AS
PRESSURES FALL ALONG THE HIGH PLAINS...AIDING IN AN INCREASED SLY
FLOW ON THE PLAINS.  THIS WILL TEND TO MAINTAIN OR ADVECT THE 60S
SURFACE DEW POINTS NWD ALONG THE DEVELOPING LEE-TROUGH.  MODIFYING
THE MIDLAND SOUNDING FOR 91/62 YIELDS MLCAPES OF 2100 J/KG AND
SIMILAR VALUES ARE EXPECTED ACROSS SWRN TX INTO ERN NM/SRN CO. 
THUS...TSTMS WILL LIKELY INITIATE IN THESE AREAS THIS AFTERNOON.

DIRECTIONAL SHEAR WILL NOT BE AS STRONG TODAY GIVEN WEAKENING
BOUNDARIES AND VERTICAL SHEAR WILL BE CORRESPONDINGLY WEAK...
INDICATIVE OF MAINLY MULTICELL STORM STRUCTURES.  BUT...MAGNITUDE OF
INSTABILITY WILL STILL MAKE ISOLD LARGE HAIL AND DAMAGING WINDS
POSSIBLE.  

...NRN PLAINS AND UPPER MS VLY...
SHOWERS ASSOCIATED WITH A MIDLEVEL SHORTWAVE TROUGH/COLD FRONT OVER
SRN SASK AND MT THIS MORNING WILL TRANSLATE RAPIDLY SEWD ACROSS THE
DAKS THIS AFTERNOON AND MN TONIGHT.  THOUGH THERE WILL LIKELY BE
STRONG THERMAL/MOISTURE ADVECTION OCCURRING TODAY AHEAD OF THE
FRONT...IT IS NOT LIKELY THAT QUALITY BOUNDARY LAYER MOISTURE WILL
ARRIVE.  WHILE THIS MAY LIMIT THE SEVERITY OF THE TSTMS...THE
LIMITED LOW LEVEL MOISTURE COULD AUGMENT DOWNDRAFT/ ISOLD DAMAGING
WIND PRODUCTION.

..RACY/CROSBIE.. 08/21/2004

...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.