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000
FXUS63 KUNR 170921
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
321 AM MDT MON JUN 17 2013

.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
ISSUED AT 320 AM MDT MON JUN 17 2013

CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER NORTHERN MN...WITH
WEAK COLD FRONT STRETCHING SOUTHEASTWARD INTO EASTERN AND SOUTH
CENTRAL SD. HIGH PRESSURE IS CENTERED OVER MT INTO SOUTHERN AB/SK.
UPPER LEVEL ANALYSIS HAS WEAK RIDGING OVER THE NORTHERN
ROCKIES...WITH WEST-NORTHWEST FLOW OVER THE NORTHERN AND CENTRAL
PLAINS. WEAK SHORTWAVE ENERGY IS MOVING ACROSS NORTHEASTERN WY AND
PRODUCING ISOLATED TO SCATTERED SHOWERS AND STORMS ACROSS THIS
AREA AND INTO SOUTHWESTERN SD. SKIES ARE VARIABLY CLOUDY WITH
TEMPS IN THE 50S TO AROUND 60 DEGREES. WINDS ARE LIGHT NORTH TO
NORTHWEST ACROSS MUCH OF THE AREA.

AN OCCASIONALLY UNSETTLED PATTERN WILL CONTINUE EARLY THIS
WEEK...WITH DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS...AS AN
UPPER LEVEL LOW PRESSURE SYSTEM REMAINS OVER THE PACIFIC NW AND WEAK
RIDGING SHIFTS INTO THE NORTHERN PLAINS BY MIDWEEK. THE LOW WILL
PUSH WEAK UPPER LEVEL DISTURBANCES OVER THE RIDGE AND INTO THE
NORTHERN PLAINS. THE BEST CHANCES FOR PCPN EARLY IN THE WEEK LOOK TO
BE ACROSS WESTERN PORTIONS OF THE CWA...SHIFTING EASTWARD BY MIDWEEK
AS THE RIDGE SLIDES SLOWLY EAST. TEMPERATURES WILL REMAIN NEAR
AVERAGE TODAY...WARMING TO ABOVE AVERAGE TUESDAY AND WEDNESDAY AS
THE THERMAL RIDGE GRADUALLY BUILDS OVER THE AREA.

FOR TODAY...SKIES WILL REMAIN VARIABLY CLOUDY...WITH THE MOST SUN
LIKELY NORTH AND EAST OF THE BLACK HILLS. LINGERING SHOWERS AND
STORMS ARE LIKELY ACROSS SOUTHWESTERN INTO SOUTH CENTRAL SD EARLY
THIS MORNING...WITH MORE SHOWERS AND THUNDERSTORMS EXPECTED TO
DEVELOP OVER WY AND THE BLACK HILLS LATE THIS MORNING AND EARLY
AFTERNOON AS ANOTHER WEAK DISTURBANCE MOVES ACROSS NORTHERN WY.
ISOLATED STRONG TO SEVERE STORMS CERTAINLY LOOK POSSIBLE ACROSS
NORTHEAST WY...THE BLACK HILLS...AND INTO SOUTHWESTERN SD AS BEST
INSTABILITY REMAINS OVER THESE AREAS. SHEAR LOOKS RELATIVELY WEAK IN
MOST AREAS...SO THE STRENGTH OF STORMS COULD BE ERRATIC. THE THREAT
FOR STRONGER STORMS WILL BE THERE THROUGHOUT THE DAY...BUT LATE
MORNING INTO THE AFTERNOON WILL BE THE MOST FAVORABLE TIME. LARGE
HAIL WOULD BE THE MAIN THREAT FROM ANY STRONGER STORMS. HIGHS WILL
GENERALLY BE IN THE 70S.

SHOWERS AND STORMS SHOULD DISSIPATE THIS EVENING...WITH MAINLY DRY
CONDITIONS OVERNIGHT. WILL GENERALLY LEAVE FORECAST DRY FOR THE
OVERNIGHT...BUT WOULD NOT BE SURPRISED TO SEE AN ISOLATED SHOWER OR
STORM WITH WEAK LOW LEVEL JET IN THE AREA...ESPECIALLY SOUTHEAST OF
THE BLACK HILLS. LOWS WILL BE IN THE MID 40S TO MID 50S.

TUESDAY WILL BE A BIT WARMER AS RIDGE SLIDES FURTHER EAST...WITH
HIGHS IN THE LOW TO MID 80S ACROSS THE PLAINS...70S IN THE BLACK
HILLS. ANOTHER ROUND OF SHOWERS AND STORMS IS EXPECTED TUESDAY
AFTERNOON INTO TUESDAY NIGHT AS A STRONGER DISTURBANCE PASSES
THROUGH...WITH COVERAGE LIKELY MORE WIDESPREAD ACROSS THE CWA. CAP
MAY BE TOUGH TO BREAK ACROSS SOUTHERN AND EASTERN AREAS DURING THE
DAY...SO THE BETTER CHANCES WILL LIKELY BE FROM NORTHEASTERN WY INTO
THE BLACK HILLS DURING THE AFTERNOON AND THEN SPREADING
EAST-NORTHEEAST INTO TUESDAY NIGHT. AGAIN...ISOLATED STRONG TO
SEVERE STORMS LOOK POSSIBLE IN THE AFTERNOON AND EVENING.

&&

.LONG TERM...WEDNESDAY THROUGH SUNDAY
ISSUED AT 320 AM MDT MON JUN 17 2013

UPPER RIDGE OVER THE NRN PLAINS MID WEEK AS UPPER LOW DIGS INTO
THE PAC NW. WEAK WAVES WILL MOVE THROUGH THE RIDGE AND PROVIDE
NEARLY DAILY CHANCE FOR TSTMS. UPPER RIDGE AXIS SHIFTS EAST OF THE
REGION LATE IN THE WEEK AS UPPER LOW MOVES INTO THE NRN
ROCKIES...WITH SOUTHWEST FLOW ALOFT BRINGING BETTER CHANCE FOR
TSTMS BACK TO THE REGION. TEMPS WILL BE NEAR TO SLIGHTLY ABOVE
AVERAGE THROUGH THE PERIOD.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING
ISSUED AT 320 AM MDT MON JUN 17 2013

SCT TSTMS EXPECTED TODAY...MAINLY ACROSS NE WY AND SW
SD. STRONG AND ERRATIC WINDS ALONG WITH HAIL POSSIBLE FROM THE
TSTMS. OTHERWISE VFR CONDITIONS EXPECTED THROUGH TONIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...26
LONG TERM...7
AVIATION...7