Severe Thunderstorm Warning 112, NWS Aberdeen, SD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ABERDEEN SD
335 PM CDT MON JUL 7 2003

.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT.
BAND OF TSRA CONTINUING ACROSS THE SOUTHERN ZONES WITH SLOW MOVEMENT
OFF TO THE EAST. EXPECT TSRA TO END THIS EVENING AS THE SFC BOUNDARY
GETS SHIFTED SOUTH AND EAST. CURRENT SFC LOW PRESSURE CENTERED OVER
WYOMING...WILL PUSH EAST THROUGH THE NIGHT. WILL HAVE SOUTHERLY FLOW
IN THE LOW LVLS...SHOWING SOME WEAK WAA OVER THE STATE TONIGHT. ALSO
HAVE A LEFT-EXIT REGION OF AN UPPER JET MAKINGS IT WAY INTO WESTERN
SD LATE TONIGHT. THE UPPER JET AND WAA SHOULD CREATE ENOUGH LIFT TO
GET SOME SHOWERS AND THUNDERSTORM DEVELOPMENT ACROSS WESTERN SOUTH
DAKOTA. THIS AREA COULD REACH FAR ENOUGH EAST INTO MY MO RIVER
COUNTIES...SO HAVE GONE WITH CHANCE POPS FOR THAT AREA AFTER 06Z
TUE. THE AREA OF LOW PRESSURE LOOKS TO TAKE MORE OF A SOUTHERLY
TRACK THAN IN PREVIOUS MODEL RUNS...BUT SHOULD STILL SEE ENOUGH LIFT
AND INSTABILITY TO WARRANT PRECIPITATION CHANCES FOR TUE INTO WED.
BY 00Z WED...ETA SHOWING UPPER DIVERGENCE BULLSEYE OVER THE AREA AS
UPPER JET CORE HAS SHIFTED EAST OVER CENTRAL SD. HAVE GONE WITH
HIGHER CHANCE POPS LATE TUE AFTERNOON INTO TUE EVENING ACROSS THE
SW...IN THE REGION OF BETTER CAPE AND INCREASED INSTABILITY. ON
WEDNESDAY...HAVE SOUTHERN SYSTEM DEPARTING THE REGION WHILE ANOTHER
WEAK WAVE IS SLIDING ACROSS SOUTHERN CANADA. THE NORTHERN SYSTEM
WILL PUSH A WEAK COLD FRONT THROUGH THE AREA WED AFTERNOON INTO WED
NIGHT. HAVE KEPT IN CHANCES FOR PRECIP AS THIS FRONT MOVES
THROUGH...WITH HIGH PRESSURE BUILDING IN BEHIND THE SYSTEM. THU
SHOULD BE DRY WITH WARMER LOW LVL TEMPS OVER THE AREA. TUE AND WED
WILL BE COOLER WITH CLOUDS AND PRECIPITATION...AS WILL GET MORE
SUNSHINE ON THU WITH SLIGHTLY WARMER TEMPERATURES.

.LONG TERM...FRIDAY THROUGH MONDAY
DURING THE PERIOD...A 500 MB RIDGE BUILDS IN THE WESTERN U.S. THEN
PROGRESSES INTO THE CENTRAL PLAINS STATES. HIGH PRESSURE IS IN
CONTROL AT THE SURFACE FOR MOST OF THE PERIOD. ON MONDAY A VORT MAX
MOVES ACROSS THE RIDGE KNOCKING IT DOWN SOMEWHAT. A LOW PRESSURE
SYSTEM ASSOCIATED WITH THIS VORT MOVES INTO THE WESTERN DAKOTAS
MONDAY. MODELS ARE SIMILAR IN HANDLING OF THESE FEATURES. WITH RIDGE
IN WESTERN U.S. TEMPS SHOULD WARM UP THOUGH IT IS NOT REFLECTED WELL
IN THE MEX GUIDANCE. RIDGE SHOULD KEEP WEATHER DRY FOR MOST OF THE
PERIOD. AT 700 MB THE VORT MOVES INTO THE DAKOTAS MONDAY. AT 850 MB
THERE IS FAIRLY STRONG WAA AND THE SURFACE FRONT ALL MOVE INTO THE
DAKOTAS ON MONDAY. THIS SHOULD BE ENOUGH TO SET OFF THUNDERSTORMS SO
HAVE INTRODUCED 30 POPS FOR LATE SUNDAY NIGHT INTO MONDAY.

.ABR...NONE

ALBRECHT/JCB

MNZ039-046-SDZ003>011-015>023-033>037-045-048-051-080945-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ABERDEEN SD
500 AM CDT MON JUL 7 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PARTS OF CENTRAL...
NORTH CENTRAL AND NORTHEAST SOUTH DAKOTA...AS WELL AS
BIG STONE AND TRAVERSE COUNTIES IN MINNESOTA.

.DAY ONE...TODAY AND TONIGHT

ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS
MORNING ACROSS PORTIONS OF NORTH CENTRAL AND CENTRAL SOUTH DAKOTA
EXTENDING EASTWARD INTO THE WATERTOWN AREA.  THE PRECIPITATION WILL
DIMINISH LATE THIS MORNING.  NONE OF THE THUNDERSTORMS ARE EXPECTED
TO BE SEVERE.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

SCATTERED THUNDERSTORMS WILL DEVELOP TUESDAY AFTERNOON ACROSS THE
AREA AND CONTINUE INTO TUESDAY NIGHT.  SOME OF THE THUNDERSTORMS MAY
BE SEVERE TUESDAY AFTERNOON AND EVENING.  THE BEST CHANCE OF SEVERE
WEATHER WILL BE ACROSS CENTRAL SOUTH DAKOTA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT.

MARSILI