[SWODY2] SWODY2

[SWODY2 at goshenarc.org]

ACUS02 KWNS 201716
SWODY2
SPC AC 201714

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1214 PM CDT FRI AUG 20 2004

VALID 211200Z - 221200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 70 NE CTB 35 W LWT 40
N WRL 20 SSE CPR 30 SW BFF 35 ESE AIA 35 E IML 25 WNW GAG 10 ENE CSM
10 NE MLC 70 ESE HRO 15 ESE CKV 25 ESE AOO 30 W ALB 30 WNW EFK
...CONT... 15 ESE PSX 20 SE DRT ...CONT... 65 WNW MRF 45 NW GDP 65
NNW SVC 25 ENE PRC 55 WSW LAS 60 ENE MER 20 SE MHS 30 SSW ONP.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 85 NE MQT 25 S RHI 30
S MCW SUX 35 WSW 9V9 50 WNW Y22 50 N GGW.

...NO SVR TSTM AREAS FORECAST...

...NRN HIGH PLAINS INTO WRN GREAT LAKES...
SHORTWAVE TROUGH CURRENTLY MOVING ONTO THE SWRN BRITISH COLUMBIA
COAST IS FORECAST TO RAPIDLY TRANSLATE SEWD...REACHING THE NRN HIGH
PLAINS BY SATURDAY AFTERNOON...AND WRN GREAT LAKES BY SUNDAY
MORNING. ATTENDANT SURFACE CYCLONE INITIALLY FORMING IN THE LEE OF
THE CANADIAN ROCKIES WILL DEEPEN AS IT CONCURRENTLY DEVELOPS SEWD
ALONG THE INTERNATIONAL BORDER. MEANWHILE...TRAILING COLD FRONT IS
EXPECTED TO SWEEP SEWD ACROSS THE NRN PLAINS DURING THE LATTER HALF
OF THE FORECAST PERIOD.

THOUGH A PLUME OF STEEP LOW- TO MID-LEVEL LAPSE RATES OF 7.5-8.5
C/KM WILL ACCOMPANY THIS SYSTEM ACROSS THE REGION...IT APPEARS THAT
THE LIMITED LOW-LEVEL MOISTURE WILL SIGNIFICANTLY IMPACT THE DEGREE
OF DESTABILIZATION /I.E. SBCAPES AOB 300-400 J/KG/ ACROSS THE WARM
SECTOR. NONETHELESS...DEEPLY-MIXED CHARACTER OF BOUNDARY-LAYER
OBSERVED IN FORECAST SOUNDINGS AHEAD OF COLD FRONT DOES SUGGEST THE
POTENTIAL FOR AT LEAST A FEW DAMAGING WIND GUSTS WITH ANY STORMS
THAT DO DEVELOP. 

STRENGTHENING SWLY LLJ ACROSS THE UPPER MS VALLEY SHOULD SUPPORT AN
INCREASE IN NOCTURNAL TSTM DEVELOPMENT SATURDAY NIGHT FROM ERN SD
ACROSS MN INTO PARTS OF WI. HOWEVER...LACK OF QUALITY LOW-LEVEL
MOISTURE WILL CONTINUE TO LIMIT INSTABILITY AND OVERALL SEVERE
THREAT.

GIVEN THE STRENGTH OF SYNOPTIC SYSTEM...DEGREE OF MOISTURE RETURN
WILL BE MONITORED. A SLIGHT RISK MAY BE REQUIRED ON SUBSEQUENT DAY 1
OUTLOOKS IF IT BECOMES APPARENT THAT GREATER INSTABILITY WILL
DEVELOP THAN IS CURRENTLY EXPECTED. 

...CNTRL/SRN HIGH PLAINS...
LEE TROUGH IS FORECAST TO SHARPEN SATURDAY IN RESPONSE TO DEEPENING
SURFACE LOW ALONG THE U.S./CANADIAN BORDER. INCREASING SLY/SELY
SURFACE WINDS E OF THIS FEATURE WILL ALLOW FOR AN INCREASE IN
BOUNDARY-LAYER MOISTURE BENEATH RATHER STEEP MID-LEVEL LAPSE RATES
OF 7-8 C/KM. WHEN COUPLED WITH STRONG DAYTIME HEATING...EXPECT
AIRMASS TO BECOME MODERATELY UNSTABLE WITH MLCAPES INCREASING TO
1000-2000 J/KG. SUSTAINED CONVERGENCE ALONG LEE TROUGH SHOULD LEAD
TO A GRADUAL EROSION OF CAP AND SUBSEQUENT INCREASE IN TSTM COVERAGE
ACROSS PARTS OF ERN CO/WRN KS SWD INTO ERN NM AND WRN TX. FORCING
FOR ASCENT AHEAD OF SHORTWAVE TROUGH APPROACHING FROM THE NW /LIKELY
FEATURE CURRENTLY OVER SERN ORE/ SHOULD ALSO AID IN AN INCREASE IN
STORM COVERAGE/INTENSITY DURING THE LATE AFTERNOON AND EVENING
HOURS.

POTENTIAL FOR ISOLATED HAIL AND/OR DAMAGING WINDS WILL EXIST WITH
STRONGEST STORMS...HOWEVER RATHER WEAK DEEP-LAYER SHEAR /AOB
25-30KT/ SHOULD TEND TO LIMIT THE SEVERE WEATHER POTENTIAL. 

...MIDDLE ATLANTIC STATES...
THOUGH WIDESPREAD CLOUDS/PRECIPITATION SHOULD EFFECTIVELY RETARD
HEATING/DESTABILIZATION AHEAD OF COLD FRONT...LATEST MODEL GUIDANCE
DOES SUGGEST SOME POTENTIAL FOR WEAK TO MODERATE INSTABILITY FROM
THE DELMARVA SWD ACROSS ERN NC. A GRADUAL INCREASE IN STORM COVERAGE
AND INTENSITY SHOULD OCCUR ALONG AND AHEAD OF FRONT THROUGH THE LATE
MORNING AND AFTERNOON HOURS...ON TRAILING EDGE OF SHORTWAVE TROUGH
SHEARING OUT ACROSS THE NERN STATES. GIVEN THE MODERATELY STRONG
WSWLY FLOW OBSERVED ON FORECAST SOUNDINGS...POTENTIAL WILL EXIST FOR
A FEW STRONG STORMS CAPABLE OF MAINLY ISOLATED DAMAGING WINDS.

..MEAD.. 08/20/2004

...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.