Severe Thunderstorm Warning 110, NWS Aberdeen, SD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ABERDEEN SD
320 PM CDT SAT JUL 5 2003

VISIBLE SATELLITE HAS SHOWERS/THUNDERSTORMS DEVELOPING ACROSS
NORTHWESTERN SD AND THE BLACK HILLS. A FEW BOUNDARIES FROM
CONVECTION IN NORTHERN NEBRASKA THIS MORNING SHOW UP ON VIS SAT AS
LINES OF TCU. WILL NEED TO WATCH THESE AS TROUGH OF LOW PRESSURE
MOVES INTO SD THIS EVENING. MODELS HAVE SURFACE LOW PRESSURE MOVING
INTO SD THIS EVENING AND SLOWLY MOVING ACROSS THE STATE ON SUNDAY.
THIS TROUGH WILL GIVE ANOTHER CHANCE OF THUNDERSTORMS FOR THE
EASTERN CWA SUNDAY AFTERNOON AND EVENING. MONDAY...A WEAK HIGH
PRESSURE SYSTEM MOVES INTO THE REGION ALLOWING FOR A BREAK IN THE
PRECIP. ANOTHER SURFACE LOW PRESSURE SYSTEM DEVELOPS ALONG THE
EASTERN SLOPES OF THE ROCKIES ON TUESDAY BEFORE PUSHING INTO WESTERN
SD EARLY WEDNESDAY. ALL OF THE MODELS ARE FAIRLY SIMILAR IN THE WAY
THEY HANDLE THESE SYSTEMS PUSHING THROUGH TONIGHT THROUGH TUESDAY
NIGHT. THE BEST CHANCE OF PRECIPITATION TONIGHT IS IN THE KPIR AREA
TONIGHT. WITH THE CURRENT CONVECTION IN THE NORTHWEST PART OF THE
STATE WILL HAVE A SLIGHT CHANCE OF THUNDERSTORMS IN THE NORTHERN
PART OF THE CWA. TUESDAY NIGHT PRECIPITATION CHANCES ARE EXPECTED TO
BE GREATEST IN THE CENTRAL PART OF THE STATE AS THE FRONT IS STILL
FURTHER WEST. TEMPERATURES SHOULD BE MOSTLY IN THE 80S FOR HIGHS AND
IN THE UPPER 50S AND 60S FOR LOWS.

.LONG TERM...WEDNESDAY THROUGH SATURDAY
MDLS ALL INDICATE 50H UPPER LEVEL RIDGING DEVELOPING INTO THE
CENTRAL PART OF THE COUNTRY FOR MID AND LATE WEEK BUT DISAGREE ON
THE AMPLITUDE OF THE RIDGE. THE CANADIAN AND THE GFS SHOW A FLATTER
RIDGE WITH S/W ENERGY MOVG ACROSS THE UPPER MIDWEST WHILE THE NOGAPS
AND ECMWF SHOW STRONGER RIDGING BUILDING INTO THE CENTRAL US
THUS...S/WS TRAVELING FURTHER NORTH AND OVER THE RIDGE. THE 12Z GFS
SHOWS A DECENT S/W AFFECTING THE CWA WED BUT DONT QUITE BUY IT AT
THIS POINT WITH THE DISAGREEMENT AMONGST THE MDLS. ALSO...THE GFS
SHOWS THE UPPER RIDGE SLIDING EAST SAT WITH SOME STRONGER S/W ENERGY
COMING IN FROM THE WEST. THIS MAY BRING SOME TSRAS TO THE AREA ON
SAT AFTN AND NIGHT. AT THIS POINT WILL CHOOSE TO KEEP IT DRY FOR
NOW. OTHERWISE...WITH THICKNESSES RISING THROUGH THE EXTENDED PERIOD
SO WILL THE DAY AND NIGHTTIME TEMPS. SKIES WILL BE CLEAR TO P/C
THROUGH THE LONG TERM PERIOD.

.ABR...NONE

JCB/ALBRECHT/MOHR

MNZ039-046-SDZ003>011-015>023-033>037-045-048-051-061030-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ABERDEEN SD
534 AM CDT SAT JUL 5 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 THUNDERSTORMS WILL DEVELOP ACROSS NORTH CENTRAL AND CENTRAL
SOUTH DAKOTA LATE THIS AFTERNOON.  BY TONIGHT THE THREAT OF
THUNDERSTORMS WILL ALSO SPREAD INTO NORTHEAST SOUTH DAKOTA AND FAR
WEST CENTRAL MINNESOTA.  THERE IS A SLIGHT RISK THAT SOME OF
THUNDERSTORMS WILL BE SEVERE LATE THIS AFTERNOON AND TONIGHT.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

SCATTERED THUNDERSTORMS WILL DEVELOP EARLY SUNDAY AFTERNOON ACROSS
CENTRAL AND NORTH CENTRAL SOUTH DAKOTA.  THUNDERSTORMS WILL THEN
OVERSPREAD NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA ON
SUNDAY EVENING.  DAMAGING WINDS AND LARGE HAIL ARE THE MAIN THREATS
WITH THESE THUNDERSTORMS.  THE THREAT FOR SEVERE WEATHER WILL
DIMINISH BY LATE SUNDAY EVENING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED LATER TODAY OR TONIGHT.

MARSILI