Severe Thunderstorm Warning 129, NWS Aberdeen, SD

AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST
SOUTH DAKOTA AND WEST CENTRAL MINNESOTA
NATIONAL WEATHER SERVICE ABERDEEN SD
300 PM CDT THU JUL 19 2001

LOOKS LIKE ANOTHER INTERESTING NIGHT ON TAP.  FOCUS FOR THIS PACKAGE
IS CONVECTION CHANCES AND EXTENT TONIGHT.  MODELS HAVING SOME
TROUBLE RESOLVING DETAILS.  SEVERAL THINGS ARE GIVEN...UPPER RIDGE
AXIS CURRENTLY OVER CENTRAL SOUTH DAKOTA.  MINOR WAVES ARE RIDING
THE WEST SIDE OF THIS FLOW.  WATER VAPOR SHOWS MINOR DISTURBANCE
CURRENTLY OVER WESTERN SOUTH DAKOTA.  VISIBLE SATELLITE SHOWING
CLOUDS FORMING IN THIS AREA.  THIS AREA HAS BOUNDARY LAYER LIFTED
INDEX VALUES OF -8.  CAPE VALUES ARE GREATER THAN 3K J/KG.
DEWPOINTS ARE NOT AS HIGH AS YESTERDAY BUT STILL IN THE 70S F.  LOW
LEVEL JET GETS ORGANIZED LATER TONIGHT AND FEEDS LIKELY AREA OF
CONVECTION.  WITH THUNDERSTORMS STARTING NOW IN THE WEST PART OF THE
AREA EXPECT STORMS TO CONTINUE THIS EVENING.  AGREE WITH SPC
DISCUSSION ABOUT STORMS LIKELY FORMING MCS THAT WILL FOLLOW THE
RIDGE TONIGHT.  WILL PUT IN ANOTHER CHANCE OF STORMS SATURDAY NIGHT
AS ANOTHER MID LEVEL WAVE MOVES OVER THE AREA.

.EXTENDED DISCUSSION...
THE STRONG UPPER RIDGE THAT HAS PLAGUED THE REGION WILL CONTINUE TO
DO SO THROUGH THE EXTENDED PERIOD. H5 HEIGHTS LOWER SOME ON THE
NORTH SIDE OF THE RIDGE DURING THE MID PART OF THE WEEK AS A SERIES
OF SHORTWAVES RIDES OVER THE RIDGE AND ACROSS THE NORTHERN PLAINS.
AT THIS TIME...IT APPEARS THE STRONGEST WAVES WILL TRACK THROUGH ON
TUESDAY AND WEDNESDAY...AT THE SAME TIME THAT A STATIONARY FRONT
SETS UP ACROSS SOUTHERN SOUTH DAKOTA AND NORTHERN NEBRASKA. HIGH
PRESSURE MOVES INTO THE AREA FOR THE LATTER PART OF THE WEEK. WILL
SEE SOME SLIGHT MODERATING TO THE TEMPS AS THE UPPER RIDGE DAMPENS
SOME...BUT EXPECT TEMPS TO STILL REMAIN NEAR OR ABOVE NORMAL.

.ABR...NONE.

KEEFE/PARKIN

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ABERDEEN SD
1114 AM CDT THU JUL 19 2001

.AFTERNOON HEATING WILL HELP TO INITIATE THUNDERSTORMS ESPECIALLY
ALONG AN OLD FRONTAL BOUNDARY ACROSS NORTHERN SOUTH DAKOTA.

SDZ003>005-009-010-015>017-033>037-045-048-051-192209-BUFFALO-CAMPBEL
L-CORSON-DEWEY-EDMUNDS-FAULK-HAND-HUGHES-HYDE-JONES-LYMAN-MCPHERSON-P
OTTER-STANLEY-SULLY-WALWORTH-
INCLUDING THE CITIES OF...EUREKA...FAULKTON...FORT PIERRE...FORT
THOMPSON...GETTYSBURG...HIGHMORE...IPSWICH...LOWER BRULE...
MCLAUGHLIN...MILLER...MOBRIDGE...MURDO...ONIDA...PIERRE...PRESHO AND
SELBY
1114 AM CDT THU JUL 19 2001

...HAZARDOUS WEATHER OUTLOOK THROUGH FRIDAY
AFTERNOON...THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND TONIGHT.
THERE IS A CHANCE THAT SOME STORMS MAY BECOME SEVERE.  THE MAIN
THREAT WILL BE LARGE HAIL AND WIND.

SPOTTER ACTIVATION MAY BE REQUIRED THIS EVENING.

MNZ039-046-SDZ006>008-011-018>023-192209-
BIG
STONE-BROWN-CLARK-CODINGTON-DAY-DEUEL-GRANT-HAMLIN-MARSHALL-ROBERTS-
SPINK-TRAVERSE-
INCLUDING THE CITIES OF...ABERDEEN...BIG STONE CITY...BRITTON...
CLARK...CLEAR LAKE...ESTELLINE...GROTON...MILBANK...ORTONVILLE...
REDFIELD...SISSETON...WATERTOWN...WEBSTER AND WHEATON
1114 AM CDT THU JUL 19 2001

...HAZARDOUS WEATHER OUTLOOK THROUGH FRIDAY AFTERNOON...
THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND TONIGHT.  THERE IS A
SLIGHT CHANCE THAT SOME STORMS MA#Y BECOME SEVERE.  THE MAIN THREAT
WILL BE LARGE HAIL AND WIND.

SPOTTER ACTIVATION MAY BE REQUIRED THIS EVENING.