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000
FXUS63 KFSD 022355
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
655 PM CDT TUE SEP 2 2014

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 331 PM CDT TUE SEP 2 2014

MAIN CONCERN FOR THE NEXT 24 HOURS WILL BE THE POTENTIAL FOR
THUNDERSTORMS LATE TONIGHT AND TOMORROW AND HOW WARM AND HUMID IT
WILL BE TOMORROW AFTERNOON.

TONIGHT WILL START OFF CLEAR WITH SOUTH TO SOUTHWEST WINDS. AS THE
PRESSURE GRADIENT TIGHTENS THIS EVENING...EXPECT THAT WINDS WILL
GRADUALLY TURN TO THE SOUTHEAST ...ESPECIALLY ALONG AND WEST OF I29.
IN ADDITION...A STRONG LOW LEVEL JET IS EXPECTED TO DEVELOP TOWARD
MIDNIGHT AND CONTINUE INTO WEDNESDAY MORNING. WITH A FAIRLY STRONG
NEAR SURFACE INVERSION IN PLACE ACROSS SOUTHWEST MINNESOTA...THIS
HAS THE POTENTIAL TO RESULT IN A DOWNSLOPE WINDS FROM MARSHALL DOWN
TO TRACY OVERNIGHT WITH GUSTS OVER 20 MPH POSSIBLE AROUND DAWN.
MEANWHILE...700-500 MB LAPSE RATES WILL BE INCREASING THROUGH THE
NIGHT. WITH MOISTURE INCREASING BELOW THE ELEVATED MIXED
LAYER...CAPES WILL BE INCREASING AFTER MIDNIGHT. THE NAM IS LIKELY
OVERDONE WITH MUCAPES APPROACHING 2500 J/KG IN SW MN BUT MUCAPES
APPROACHING 1000 J/KG ARE POSSIBLE BY 12Z WED. AT THE SAME
TIME...WITH STRONG WARM AIR ADVECTION AND WEAK SYNOPTIC SCALE
FORCING FOR ASCENT...EXPECT THE POSSIBILITY OF ELEVATED
THUNDERSTORMS WILL INCREASE AFTER 06Z. THE FIRST STORMS MAY DEVELOP
AS FAR WEST OF HURON...SIOUX FALLS AND STORM LAKE BUT THE MOST
LIKELY AREA WILL BE IN SW MN AFTER 09Z. EFFECTIVE SHEAR WILL BE
LIMITED...20 TO 30 KTS...AS WILL INSTABILITY...BUT STRONG ENOUGH
UPDRAFTS MAY DEVELOP TO RESULT IN SMALL HAIL IN THE STRONGEST STORMS
PRIOR TO 12Z. LOWS TONIGHT WILL GENERALLY BE IN THE 60S...WITH
WARMEST READINGS IN SOUTH CENTRAL SD AND COOLEST READINGS AROUND SPW.

ELEVATED CONVECTION IS EXPECTED TO CONTINUE TOMORROW
MORNING...PRIMARILY IN SW MN. LAPSE RATES AND MOISTURE WILL CONTINUE
TO INCREASE THROUGH THE MORNING ACROSS THE AREA. A VERY WARM LAYER
FROM 800 TO 700 HPA WILL BECOME ESTABLISHED OVER MUCH OF SE SD...NE
NEBRASKA...AND NW IA BY LATE MORNING WHICH IS EXPECTED TO SUPPRESS
CONVECTION IN THESE AREAS. HOWEVER...IF STORMS ARE ABLE TO DEVELOP
ON THE SW SIDE OF THE PRECIPITATION BAND OVER DURING THE MID TO LATE
MORNING...INCREASING CAPES...APPROACHING 1500 TO 2000 J/KG AND
SHEAR...APPROACHING 40 KTS...WOULD SUPPORT UP TO HALF DOLLAR SIZE
HAIL. BUT CONFIDENCE OF THIS HAPPENING IS LOW. THERE IS ANOTHER WAVE
MOVING FROM EAST CENTRAL SD INTO CENTRAL MN LATE WED AFTERNOON. AT
THIS POINT...THE BEST CHANCE FOR LATE AFTERNOON DEVELOPMENT WILL BE
ALONG AND EAST OF THE MINNESOTA RIVER. HOWEVER...IT IS POSSIBLE THAT
THE PRESENCE OF LEFT OVER OUTFLOW BOUNDARIES AND/OR DIFFERENTIAL
DIABATIC HEATING COULD RESULT IN A ONE OR TWO STORMS DEVELOPING IN
THE VICINITY OF MARSHALL. WHILE A VERY LOW PROBABILITY...LESS THAN
20 PERCENT...IF STORMS DO DEVELOP...THEY WOULD HAVE THE POTENTIAL TO
EVOLVE INTO SEVERE SUPERCELLS AS CAPES WOULD BE GREATER THAN 2000
J/KG AND EFFECTIVE SHEAR GREATER THAN 40 KTS. FOR NOW WILL HIGHLIGHT
THE LOW PROBABILITY OF SEVERE STORMS IN THE MORNING. HIGHS TOMORROW
ARE VERY DEPENDENT ON CLOUD COVER. WEST OF THE JAMES RIVER...EXPECT
HIGHS TO REACH THE LOW 90S WITH LOTS OF SUN...WHILE IN SW MN LOWER
80S ARE EXPECTED WITH CLOUDS MUCH OF THE DAY. WITH A STRONG
INVERSION IN PLACE...DEW POINTS WILL RISE INTO THE 70S RESULTING IN
HEAT INDICES OF 90 TO 100 DEGREES WEST OF I29 WEDNESDAY AFTERNOON.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CDT TUE SEP 2 2014

MODELS ARE IN PRETTY GOOD AGREEMENT THAT SURFACE LOW PRESSURE WILL
DEEPEN OVER CENTRAL SOUTH DAKOTA ON WEDNESDAY NIGHT...THEN RAPIDLY
LIFT NORTHEAST INTO NORTHERN MINNESOTA BY MIDDAY THURSDAY. A MID
LEVEL SHORTWAVE LIFTING INTO EAST CENTRAL MINNESOTA WILL ALLOW ANY
ISOLATED THUNDERSTORM ACTIVITY NEAR THE BUFFALO RIDGE AREA EARLY
WEDNESDAY EVENING TO EXIT THE FORECAST AREA QUICKLY. EARLY WEDNESDAY
NIGHT HOWEVER...A FAIRLY POTENT COLD FRONT DROPS INTO CENTRAL SOUTH
DAKOTA AND MOVES INTO THE JAMES VALLEY REGION LATE AT NIGHT.
SCATTERED TO ISOLATED SHOWERS WITH A FEW RUMBLES OF THUNDER WILL
DEVELOP ALONG AND JUST BEHIND THE FRONT. DID SPEED UP THE TIMING OF
THE FRONT SLIGHTLY...WHICH BRINGS IT INTO THE I29 CORRIDOR LATE
MORNING AND ACROSS OUR SOUTHEASTERN CWA THURSDAY LATE AFTERNOON.
STRONG CAPPING AND SOMEWHAT WEAK SUPPORT ATTENDING THE FRONT WILL
KEEP PRECIPITATION CHANCES LIMITED TO LOW END CHANCES FOR SHOWERS AND
NON SEVERE THUNDERSTORMS.

DRY AIR FILTERS INTO THE REGION THURSDAY NIGHT AS SURFACE HIGH
PRESSURE RAPIDLY EXPANDS INTO THE REGION. COOL AND DRY NORTHWEST
FLOW SETS UP FRIDAY INTO THE WEEKEND...LEADING TO SOME
PLEASANT...BUT UNSEASONABLY COOL WEATHER CONDITIONS. AFTERNOON HIGHS
ONLY TOP OUT IN THE UPPER 60S AND LOWER 70S ON FRIDAY AND
SATURDAY...AND IMPROVING A FEW DEGREES ON SUNDAY. OVERNIGHT LOWS
HAVE THE POTENTIAL TO BE QUITE COOL AS WELL WITH MOSTLY CLEAR SKIES
AND RELATIVELY LIGHT WINDS. LOWS SHOULD DROP INTO MID 40S TO LOW
50S...AND HAVE CONTINUED TO TREND BELOW THE ALLBLEND GUIDANCE.

MODELS SHOWING BETTER AGREEMENT THIS AFTERNOON REGARDING THE PATTERN
EVOLUTION EARLY NEXT WEEK. FLOW TURNS MORE ZONAL ON SUNDAY AND
SUNDAY EVENING...WITH A SOUTHERLY LOW LEVEL FETCH. THIS WILL ALLOW A
GREATER MOISTURE RETURN SUNDAY NIGHT INTO MONDAY NIGHT AHEAD OF THE
STRONG WAVE EMERGING FROM THE INTERMOUNTAIN WEST INTO CENTRAL HIGH
PLAINS MONDAY AFTERNOON. WITH WARM AIR ADVECTION AND INCREASED
MOISTURE...THUNDERSTORM CHANCES INCREASE MONDAY AND TUESDAY. MODELS
SUGGEST SOME CYCLOGENESIS FORMS IN THE VICINITY OF WESTERN SOUTH
DAKOTA EARLY TUESDAY. GIVEN THE DECENT AGREEMENT IN PLACEMENT
BETWEEN THE GFS AND ECMWF...AGREE WITH THE HIGH END CHANCE POPS FOR
MUCH OF THE FORECAST AREA. TEMPERATURES CONTINUE TO WARM A FEW
DURING THIS PERIOD...BUT SHOULD REMAIN NEAR OR JUST BELOW NORMAL.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 655 PM CDT TUE SEP 2 2014

MAIN ISSUES FOR TAFS ARE CONVECTION...POTENTIAL FOR LOW LEVEL WIND
SHEAR AND LOW CLOUDS. THROUGH 06Z WED...VFR CONDITIONS EXPECTED
ALTHOUGH WINDS WILL GRADUALLY BACK TO SOUTHEAST IN ALL LOCATIONS IN
THE EVENING. AFTER 06Z...STRENGTHENING LOW LEVEL JET AND INCREASING
INSTABILITY ARE EXPECTED TO SPARK DEVELOPMENT OF THUNDERSTORMS PRIOR
TO DAWN. WHILE A STORM IS POSSIBLE IN KFSD OR KHON...THE BEST CHANCE
WILL BE IN SW MN. THEREFORE DID NOT INCLUDE TSRA IN TAF FOR EITHER
SITE. HOWEVER...WITH A 40-50 KT LOW LEVEL JET FROM EASTERN NEBRASKA
INTO SOUTHWEST MN LATE TONIGHT AND EARLY THU MORNING...THERE IS THE
POTENTIAL FOR NON CONVECTIVE LOW LEVEL WIND SHEAR. CORE OF THE JET
EXPECTED TO REMAIN EAST OF KHON...BUT COULD AFFECT KFSD/KSUX...WITH
DIRECTIONAL SHEAR LOCALLY ENHANCED AT KSUX DUE TO EXPECTED LOCAL
EFFECT IN MISSOURI RIVER VALLEY CAUSING MORE OF AN EAST-SOUTHEAST
COMPONENT IN THE SURFACE WIND.

THE OTHER CONCERN IS DEVELOPMENT OF MVFR CEILINGS WEDNESDAY MORNING.
ALL MODELS SHOW MOISTURE INCREASING BELOW A FAIRLY STRONG INVERSION
SO EXPECT CIGS FROM 1000 TO 2000 FT TO DEVELOP AT KFSD AND KSUX
SHORTLY AFTER SUNRISE. WITH LESS MOISTURE EXPECTED AT KHON...KEPT
MAINLY VFR CONDITIONS FOR NOW...THOUGH DID INTRODUCE A SMALL WINDOW
OF HIGHER MVFR CEILINGS AROUND MIDDAY/EARLY AFTERNOON.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...SCHUMACHER
LONG TERM...
AVIATION...JH




000
FXUS63 KFSD 022355
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
655 PM CDT TUE SEP 2 2014

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 331 PM CDT TUE SEP 2 2014

MAIN CONCERN FOR THE NEXT 24 HOURS WILL BE THE POTENTIAL FOR
THUNDERSTORMS LATE TONIGHT AND TOMORROW AND HOW WARM AND HUMID IT
WILL BE TOMORROW AFTERNOON.

TONIGHT WILL START OFF CLEAR WITH SOUTH TO SOUTHWEST WINDS. AS THE
PRESSURE GRADIENT TIGHTENS THIS EVENING...EXPECT THAT WINDS WILL
GRADUALLY TURN TO THE SOUTHEAST ...ESPECIALLY ALONG AND WEST OF I29.
IN ADDITION...A STRONG LOW LEVEL JET IS EXPECTED TO DEVELOP TOWARD
MIDNIGHT AND CONTINUE INTO WEDNESDAY MORNING. WITH A FAIRLY STRONG
NEAR SURFACE INVERSION IN PLACE ACROSS SOUTHWEST MINNESOTA...THIS
HAS THE POTENTIAL TO RESULT IN A DOWNSLOPE WINDS FROM MARSHALL DOWN
TO TRACY OVERNIGHT WITH GUSTS OVER 20 MPH POSSIBLE AROUND DAWN.
MEANWHILE...700-500 MB LAPSE RATES WILL BE INCREASING THROUGH THE
NIGHT. WITH MOISTURE INCREASING BELOW THE ELEVATED MIXED
LAYER...CAPES WILL BE INCREASING AFTER MIDNIGHT. THE NAM IS LIKELY
OVERDONE WITH MUCAPES APPROACHING 2500 J/KG IN SW MN BUT MUCAPES
APPROACHING 1000 J/KG ARE POSSIBLE BY 12Z WED. AT THE SAME
TIME...WITH STRONG WARM AIR ADVECTION AND WEAK SYNOPTIC SCALE
FORCING FOR ASCENT...EXPECT THE POSSIBILITY OF ELEVATED
THUNDERSTORMS WILL INCREASE AFTER 06Z. THE FIRST STORMS MAY DEVELOP
AS FAR WEST OF HURON...SIOUX FALLS AND STORM LAKE BUT THE MOST
LIKELY AREA WILL BE IN SW MN AFTER 09Z. EFFECTIVE SHEAR WILL BE
LIMITED...20 TO 30 KTS...AS WILL INSTABILITY...BUT STRONG ENOUGH
UPDRAFTS MAY DEVELOP TO RESULT IN SMALL HAIL IN THE STRONGEST STORMS
PRIOR TO 12Z. LOWS TONIGHT WILL GENERALLY BE IN THE 60S...WITH
WARMEST READINGS IN SOUTH CENTRAL SD AND COOLEST READINGS AROUND SPW.

ELEVATED CONVECTION IS EXPECTED TO CONTINUE TOMORROW
MORNING...PRIMARILY IN SW MN. LAPSE RATES AND MOISTURE WILL CONTINUE
TO INCREASE THROUGH THE MORNING ACROSS THE AREA. A VERY WARM LAYER
FROM 800 TO 700 HPA WILL BECOME ESTABLISHED OVER MUCH OF SE SD...NE
NEBRASKA...AND NW IA BY LATE MORNING WHICH IS EXPECTED TO SUPPRESS
CONVECTION IN THESE AREAS. HOWEVER...IF STORMS ARE ABLE TO DEVELOP
ON THE SW SIDE OF THE PRECIPITATION BAND OVER DURING THE MID TO LATE
MORNING...INCREASING CAPES...APPROACHING 1500 TO 2000 J/KG AND
SHEAR...APPROACHING 40 KTS...WOULD SUPPORT UP TO HALF DOLLAR SIZE
HAIL. BUT CONFIDENCE OF THIS HAPPENING IS LOW. THERE IS ANOTHER WAVE
MOVING FROM EAST CENTRAL SD INTO CENTRAL MN LATE WED AFTERNOON. AT
THIS POINT...THE BEST CHANCE FOR LATE AFTERNOON DEVELOPMENT WILL BE
ALONG AND EAST OF THE MINNESOTA RIVER. HOWEVER...IT IS POSSIBLE THAT
THE PRESENCE OF LEFT OVER OUTFLOW BOUNDARIES AND/OR DIFFERENTIAL
DIABATIC HEATING COULD RESULT IN A ONE OR TWO STORMS DEVELOPING IN
THE VICINITY OF MARSHALL. WHILE A VERY LOW PROBABILITY...LESS THAN
20 PERCENT...IF STORMS DO DEVELOP...THEY WOULD HAVE THE POTENTIAL TO
EVOLVE INTO SEVERE SUPERCELLS AS CAPES WOULD BE GREATER THAN 2000
J/KG AND EFFECTIVE SHEAR GREATER THAN 40 KTS. FOR NOW WILL HIGHLIGHT
THE LOW PROBABILITY OF SEVERE STORMS IN THE MORNING. HIGHS TOMORROW
ARE VERY DEPENDENT ON CLOUD COVER. WEST OF THE JAMES RIVER...EXPECT
HIGHS TO REACH THE LOW 90S WITH LOTS OF SUN...WHILE IN SW MN LOWER
80S ARE EXPECTED WITH CLOUDS MUCH OF THE DAY. WITH A STRONG
INVERSION IN PLACE...DEW POINTS WILL RISE INTO THE 70S RESULTING IN
HEAT INDICES OF 90 TO 100 DEGREES WEST OF I29 WEDNESDAY AFTERNOON.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CDT TUE SEP 2 2014

MODELS ARE IN PRETTY GOOD AGREEMENT THAT SURFACE LOW PRESSURE WILL
DEEPEN OVER CENTRAL SOUTH DAKOTA ON WEDNESDAY NIGHT...THEN RAPIDLY
LIFT NORTHEAST INTO NORTHERN MINNESOTA BY MIDDAY THURSDAY. A MID
LEVEL SHORTWAVE LIFTING INTO EAST CENTRAL MINNESOTA WILL ALLOW ANY
ISOLATED THUNDERSTORM ACTIVITY NEAR THE BUFFALO RIDGE AREA EARLY
WEDNESDAY EVENING TO EXIT THE FORECAST AREA QUICKLY. EARLY WEDNESDAY
NIGHT HOWEVER...A FAIRLY POTENT COLD FRONT DROPS INTO CENTRAL SOUTH
DAKOTA AND MOVES INTO THE JAMES VALLEY REGION LATE AT NIGHT.
SCATTERED TO ISOLATED SHOWERS WITH A FEW RUMBLES OF THUNDER WILL
DEVELOP ALONG AND JUST BEHIND THE FRONT. DID SPEED UP THE TIMING OF
THE FRONT SLIGHTLY...WHICH BRINGS IT INTO THE I29 CORRIDOR LATE
MORNING AND ACROSS OUR SOUTHEASTERN CWA THURSDAY LATE AFTERNOON.
STRONG CAPPING AND SOMEWHAT WEAK SUPPORT ATTENDING THE FRONT WILL
KEEP PRECIPITATION CHANCES LIMITED TO LOW END CHANCES FOR SHOWERS AND
NON SEVERE THUNDERSTORMS.

DRY AIR FILTERS INTO THE REGION THURSDAY NIGHT AS SURFACE HIGH
PRESSURE RAPIDLY EXPANDS INTO THE REGION. COOL AND DRY NORTHWEST
FLOW SETS UP FRIDAY INTO THE WEEKEND...LEADING TO SOME
PLEASANT...BUT UNSEASONABLY COOL WEATHER CONDITIONS. AFTERNOON HIGHS
ONLY TOP OUT IN THE UPPER 60S AND LOWER 70S ON FRIDAY AND
SATURDAY...AND IMPROVING A FEW DEGREES ON SUNDAY. OVERNIGHT LOWS
HAVE THE POTENTIAL TO BE QUITE COOL AS WELL WITH MOSTLY CLEAR SKIES
AND RELATIVELY LIGHT WINDS. LOWS SHOULD DROP INTO MID 40S TO LOW
50S...AND HAVE CONTINUED TO TREND BELOW THE ALLBLEND GUIDANCE.

MODELS SHOWING BETTER AGREEMENT THIS AFTERNOON REGARDING THE PATTERN
EVOLUTION EARLY NEXT WEEK. FLOW TURNS MORE ZONAL ON SUNDAY AND
SUNDAY EVENING...WITH A SOUTHERLY LOW LEVEL FETCH. THIS WILL ALLOW A
GREATER MOISTURE RETURN SUNDAY NIGHT INTO MONDAY NIGHT AHEAD OF THE
STRONG WAVE EMERGING FROM THE INTERMOUNTAIN WEST INTO CENTRAL HIGH
PLAINS MONDAY AFTERNOON. WITH WARM AIR ADVECTION AND INCREASED
MOISTURE...THUNDERSTORM CHANCES INCREASE MONDAY AND TUESDAY. MODELS
SUGGEST SOME CYCLOGENESIS FORMS IN THE VICINITY OF WESTERN SOUTH
DAKOTA EARLY TUESDAY. GIVEN THE DECENT AGREEMENT IN PLACEMENT
BETWEEN THE GFS AND ECMWF...AGREE WITH THE HIGH END CHANCE POPS FOR
MUCH OF THE FORECAST AREA. TEMPERATURES CONTINUE TO WARM A FEW
DURING THIS PERIOD...BUT SHOULD REMAIN NEAR OR JUST BELOW NORMAL.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 655 PM CDT TUE SEP 2 2014

MAIN ISSUES FOR TAFS ARE CONVECTION...POTENTIAL FOR LOW LEVEL WIND
SHEAR AND LOW CLOUDS. THROUGH 06Z WED...VFR CONDITIONS EXPECTED
ALTHOUGH WINDS WILL GRADUALLY BACK TO SOUTHEAST IN ALL LOCATIONS IN
THE EVENING. AFTER 06Z...STRENGTHENING LOW LEVEL JET AND INCREASING
INSTABILITY ARE EXPECTED TO SPARK DEVELOPMENT OF THUNDERSTORMS PRIOR
TO DAWN. WHILE A STORM IS POSSIBLE IN KFSD OR KHON...THE BEST CHANCE
WILL BE IN SW MN. THEREFORE DID NOT INCLUDE TSRA IN TAF FOR EITHER
SITE. HOWEVER...WITH A 40-50 KT LOW LEVEL JET FROM EASTERN NEBRASKA
INTO SOUTHWEST MN LATE TONIGHT AND EARLY THU MORNING...THERE IS THE
POTENTIAL FOR NON CONVECTIVE LOW LEVEL WIND SHEAR. CORE OF THE JET
EXPECTED TO REMAIN EAST OF KHON...BUT COULD AFFECT KFSD/KSUX...WITH
DIRECTIONAL SHEAR LOCALLY ENHANCED AT KSUX DUE TO EXPECTED LOCAL
EFFECT IN MISSOURI RIVER VALLEY CAUSING MORE OF AN EAST-SOUTHEAST
COMPONENT IN THE SURFACE WIND.

THE OTHER CONCERN IS DEVELOPMENT OF MVFR CEILINGS WEDNESDAY MORNING.
ALL MODELS SHOW MOISTURE INCREASING BELOW A FAIRLY STRONG INVERSION
SO EXPECT CIGS FROM 1000 TO 2000 FT TO DEVELOP AT KFSD AND KSUX
SHORTLY AFTER SUNRISE. WITH LESS MOISTURE EXPECTED AT KHON...KEPT
MAINLY VFR CONDITIONS FOR NOW...THOUGH DID INTRODUCE A SMALL WINDOW
OF HIGHER MVFR CEILINGS AROUND MIDDAY/EARLY AFTERNOON.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...SCHUMACHER
LONG TERM...
AVIATION...JH





000
FXUS63 KFSD 022032
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
332 PM CDT TUE SEP 2 2014

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 331 PM CDT TUE SEP 2 2014

MAIN CONCERN FOR THE NEXT 24 HOURS WILL BE THE POTENTIAL FOR
THUNDERSTORMS LATE TONIGHT AND TOMORROW AND HOW WARM AND HUMID IT
WILL BE TOMORROW AFTERNOON.

TONIGHT WILL START OFF CLEAR WITH SOUTH TO SOUTHWEST WINDS. AS THE
PRESSURE GRADIENT TIGHTENS THIS EVENING...EXPECT THAT WINDS WILL
GRADUALLY TURN TO THE SOUTHEAST ...ESPECIALLY ALONG AND WEST OF I29.
IN ADDITION...A STRONG LOW LEVEL JET IS EXPECTED TO DEVELOP TOWARD
MIDNIGHT AND CONTINUE INTO WEDNESDAY MORNING. WITH A FAIRLY STRONG
NEAR SURFACE INVERSION IN PLACE ACROSS SOUTHWEST MINNESOTA...THIS
HAS THE POTENTIAL TO RESULT IN A DOWNSLOPE WINDS FROM MARSHALL DOWN
TO TRACY OVERNIGHT WITH GUSTS OVER 20 MPH POSSIBLE AROUND DAWN.
MEANWHILE...700-500 MB LAPSE RATES WILL BE INCREASING THROUGH THE
NIGHT. WITH MOISTURE INCREASING BELOW THE ELEVATED MIXED
LAYER...CAPES WILL BE INCREASING AFTER MIDNIGHT. THE NAM IS LIKELY
OVERDONE WITH MUCAPES APPROACHING 2500 J/KG IN SW MN BUT MUCAPES
APPROACHING 1000 J/KG ARE POSSIBLE BY 12Z WED. AT THE SAME
TIME...WITH STRONG WARM AIR ADVECTION AND WEAK SYNOPTIC SCALE
FORCING FOR ASCENT...EXPECT THE POSSIBILITY OF ELEVATED
THUNDERSTORMS WILL INCREASE AFTER 06Z. THE FIRST STORMS MAY DEVELOP
AS FAR WEST OF HURON...SIOUX FALLS AND STORM LAKE BUT THE MOST
LIKELY AREA WILL BE IN SW MN AFTER 09Z. EFFECTIVE SHEAR WILL BE
LIMITED...20 TO 30 KTS...AS WILL INSTABILITY...BUT STRONG ENOUGH
UPDRAFTS MAY DEVELOP TO RESULT IN SMALL HAIL IN THE STRONGEST STORMS
PRIOR TO 12Z. LOWS TONIGHT WILL GENERALLY BE IN THE 60S...WITH
WARMEST READINGS IN SOUTH CENTRAL SD AND COOLEST READINGS AROUND SPW.

ELEVATED CONVECTION IS EXPECTED TO CONTINUE TOMORROW
MORNING...PRIMARILY IN SW MN. LAPSE RATES AND MOISTURE WILL CONTINUE
TO INCREASE THROUGH THE MORNING ACROSS THE AREA. A VERY WARM LAYER
FROM 800 TO 700 HPA WILL BECOME ESTABLISHED OVER MUCH OF SE SD...NE
NEBRASKA...AND NW IA BY LATE MORNING WHICH IS EXPECTED TO SUPPRESS
CONVECTION IN THESE AREAS. HOWEVER...IF STORMS ARE ABLE TO DEVELOP
ON THE SW SIDE OF THE PRECIPITATION BAND OVER DURING THE MID TO LATE
MORNING...INCREASING CAPES...APPROACHING 1500 TO 2000 J/KG AND
SHEAR...APPROACHING 40 KTS...WOULD SUPPORT UP TO HALF DOLLAR SIZE
HAIL. BUT CONFIDENCE OF THIS HAPPENING IS LOW. THERE IS ANOTHER WAVE
MOVING FROM EAST CENTRAL SD INTO CENTRAL MN LATE WED AFTERNOON. AT
THIS POINT...THE BEST CHANCE FOR LATE AFTERNOON DEVELOPMENT WILL BE
ALONG AND EAST OF THE MINNESOTA RIVER. HOWEVER...IT IS POSSIBLE THAT
THE PRESENCE OF LEFT OVER OUTFLOW BOUNDARIES AND/OR DIFFERENTIAL
DIABATIC HEATING COULD RESULT IN A ONE OR TWO STORMS DEVELOPING IN
THE VICINITY OF MARSHALL. WHILE A VERY LOW PROBABILITY...LESS THAN
20 PERCENT...IF STORMS DO DEVELOP...THEY WOULD HAVE THE POTENTIAL TO
EVOLVE INTO SEVERE SUPERCELLS AS CAPES WOULD BE GREATER THAN 2000
J/KG AND EFFECTIVE SHEAR GREATER THAN 40 KTS. FOR NOW WILL HIGHLIGHT
THE LOW PROBABILITY OF SEVERE STORMS IN THE MORNING. HIGHS TOMORROW
ARE VERY DEPENDENT ON CLOUD COVER. WEST OF THE JAMES RIVER...EXPECT
HIGHS TO REACH THE LOW 90S WITH LOTS OF SUN...WHILE IN SW MN LOWER
80S ARE EXPECTED WITH CLOUDS MUCH OF THE DAY. WITH A STRONG
INVERSION IN PLACE...DEW POINTS WILL RISE INTO THE 70S RESULTING IN
HEAT INDICES OF 90 TO 100 DEGREES WEST OF I29 WEDNESDAY AFTERNOON.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CDT TUE SEP 2 2014

MODELS ARE IN PRETTY GOOD AGREEMENT THAT SURFACE LOW PRESSURE WILL
DEEPEN OVER CENTRAL SOUTH DAKOTA ON WEDNESDAY NIGHT...THEN RAPIDLY
LIFT NORTHEAST INTO NORTHERN MINNESOTA BY MIDDAY THURSDAY. A MID
LEVEL SHORTWAVE LIFTING INTO EAST CENTRAL MINNESOTA WILL ALLOW ANY
ISOLATED THUNDERSTORM ACTIVITY NEAR THE BUFFALO RIDGE AREA EARLY
WEDNESDAY EVENING TO EXIT THE FORECAST AREA QUICKLY. EARLY WEDNESDAY
NIGHT HOWEVER...A FAIRLY POTENT COLD FRONT DROPS INTO CENTRAL SOUTH
DAKOTA AND MOVES INTO THE JAMES VALLEY REGION LATE AT NIGHT.
SCATTERED TO ISOLATED SHOWERS WITH A FEW RUMBLES OF THUNDER WILL
DEVELOP ALONG AND JUST BEHIND THE FRONT. DID SPEED UP THE TIMING OF
THE FRONT SLIGHTLY...WHICH BRINGS IT INTO THE I29 CORRIDOR LATE
MORNING AND ACROSS OUR SOUTHEASTERN CWA THURSDAY LATE AFTERNOON.
STRONG CAPPING AND SOMEWHAT WEAK SUPPORT ATTENDING THE FRONT WILL
KEEP PRECIPITATION CHANCES LIMITED TO LOW END CHANCES FOR SHOWERS AND
NON SEVERE THUNDERSTORMS.

DRY AIR FILTERS INTO THE REGION THURSDAY NIGHT AS SURFACE HIGH
PRESSURE RAPIDLY EXPANDS INTO THE REGION. COOL AND DRY NORTHWEST
FLOW SETS UP FRIDAY INTO THE WEEKEND...LEADING TO SOME
PLEASANT...BUT UNSEASONABLY COOL WEATHER CONDITIONS. AFTERNOON HIGHS
ONLY TOP OUT IN THE UPPER 60S AND LOWER 70S ON FRIDAY AND
SATURDAY...AND IMPROVING A FEW DEGREES ON SUNDAY. OVERNIGHT LOWS
HAVE THE POTENTIAL TO BE QUITE COOL AS WELL WITH MOSTLY CLEAR SKIES
AND RELATIVELY LIGHT WINDS. LOWS SHOULD DROP INTO MID 40S TO LOW
50S...AND HAVE CONTINUED TO TREND BELOW THE ALLBLEND GUIDANCE.

MODELS SHOWING BETTER AGREEMENT THIS AFTERNOON REGARDING THE PATTERN
EVOLUTION EARLY NEXT WEEK. FLOW TURNS MORE ZONAL ON SUNDAY AND
SUNDAY EVENING...WITH A SOUTHERLY LOW LEVEL FETCH. THIS WILL ALLOW A
GREATER MOISTURE RETURN SUNDAY NIGHT INTO MONDAY NIGHT AHEAD OF THE
STRONG WAVE EMERGING FROM THE INTERMOUNTAIN WEST INTO CENTRAL HIGH
PLAINS MONDAY AFTERNOON. WITH WARM AIR ADVECTION AND INCREASED
MOISTURE...THUNDERSTORM CHANCES INCREASE MONDAY AND TUESDAY. MODELS
SUGGEST SOME CYCLOGENESIS FORMS IN THE VICINITY OF WESTERN SOUTH
DAKOTA EARLY TUESDAY. GIVEN THE DECENT AGREEMENT IN PLACEMENT
BETWEEN THE GFS AND ECMWF...AGREE WITH THE HIGH END CHANCE POPS FOR
MUCH OF THE FORECAST AREA. TEMPERATURES CONTINUE TO WARM A FEW
DURING THIS PERIOD...BUT SHOULD REMAIN NEAR OR JUST BELOW NORMAL.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1222 PM CDT TUE SEP 2 2014

MAIN ISSUE FOR TAFS ARE CONVECTION...POTENTIAL FOR LOW LEVEL WIND
SHEAR AND LOW CLOUDS. THROUGH 06Z WED...VFR CONDITIONS EXPECTED
ALTHOUGH WINDS WILL GRADUALLY BACK TO SOUTHEAST IN ALL LOCATION IN
THE EVENING. AFTER 06Z...A STRENGTHENING LOW LEVEL JET AND
INCREASING INSTABILITY ARE EXPECTED TO RESULT IN THE DEVELOPMENT
OF THUNDERSTORMS PRIOR TO DAWN. WHILE A STORM IS POSSIBLE IN KFSD
OR KHON...THE BEST CHANCE WILL BE IN SW MN. THEREFORE DID NOT
INCLUDE TSRA IN TAF FOR EITHER SITE. HOWEVER...WITH A 40 TO 50 KT
LOW LEVEL JET FROM SOUTHEAST SD IN SW MN LATE TONIGHT AND EARLY
THU MORNING...THERE IS THE POTENTIAL FOR NON CONVECTIVE LOW LEVEL
WIND SHEAR. WITH CORE OF THE JET GOING THROUGH THE KFSD AREA...DID
ADD LOW LEVEL WIND SHEAR FOR SIOUX FALLS...BUT SUBSEQUENT SHIFTS
WILL NEED TO EXAMINE POTENTIAL IN KHON. THE OTHER CONCERN IS
DEVELOPMENT OF MVFR CEILINGS WEDNESDAY MORNING. ALL MODELS SHOW
MOISTURE INCREASING BELOW A FAIRLY STRONG INVERSION SO EXPECT CIGS
FROM 1000 TO 2000 FT TO DEVELOP AT KFSD AND KSUX SHORTLY AFTER
SUNRISE. WITH LESS MOISTURE EXPECTED AT KHON...KEPT VFR CONDITIONS
FOR NOW.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...SCHUMACHER
LONG TERM...
AVIATION...SCHUMACHER




000
FXUS63 KFSD 022032
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
332 PM CDT TUE SEP 2 2014

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 331 PM CDT TUE SEP 2 2014

MAIN CONCERN FOR THE NEXT 24 HOURS WILL BE THE POTENTIAL FOR
THUNDERSTORMS LATE TONIGHT AND TOMORROW AND HOW WARM AND HUMID IT
WILL BE TOMORROW AFTERNOON.

TONIGHT WILL START OFF CLEAR WITH SOUTH TO SOUTHWEST WINDS. AS THE
PRESSURE GRADIENT TIGHTENS THIS EVENING...EXPECT THAT WINDS WILL
GRADUALLY TURN TO THE SOUTHEAST ...ESPECIALLY ALONG AND WEST OF I29.
IN ADDITION...A STRONG LOW LEVEL JET IS EXPECTED TO DEVELOP TOWARD
MIDNIGHT AND CONTINUE INTO WEDNESDAY MORNING. WITH A FAIRLY STRONG
NEAR SURFACE INVERSION IN PLACE ACROSS SOUTHWEST MINNESOTA...THIS
HAS THE POTENTIAL TO RESULT IN A DOWNSLOPE WINDS FROM MARSHALL DOWN
TO TRACY OVERNIGHT WITH GUSTS OVER 20 MPH POSSIBLE AROUND DAWN.
MEANWHILE...700-500 MB LAPSE RATES WILL BE INCREASING THROUGH THE
NIGHT. WITH MOISTURE INCREASING BELOW THE ELEVATED MIXED
LAYER...CAPES WILL BE INCREASING AFTER MIDNIGHT. THE NAM IS LIKELY
OVERDONE WITH MUCAPES APPROACHING 2500 J/KG IN SW MN BUT MUCAPES
APPROACHING 1000 J/KG ARE POSSIBLE BY 12Z WED. AT THE SAME
TIME...WITH STRONG WARM AIR ADVECTION AND WEAK SYNOPTIC SCALE
FORCING FOR ASCENT...EXPECT THE POSSIBILITY OF ELEVATED
THUNDERSTORMS WILL INCREASE AFTER 06Z. THE FIRST STORMS MAY DEVELOP
AS FAR WEST OF HURON...SIOUX FALLS AND STORM LAKE BUT THE MOST
LIKELY AREA WILL BE IN SW MN AFTER 09Z. EFFECTIVE SHEAR WILL BE
LIMITED...20 TO 30 KTS...AS WILL INSTABILITY...BUT STRONG ENOUGH
UPDRAFTS MAY DEVELOP TO RESULT IN SMALL HAIL IN THE STRONGEST STORMS
PRIOR TO 12Z. LOWS TONIGHT WILL GENERALLY BE IN THE 60S...WITH
WARMEST READINGS IN SOUTH CENTRAL SD AND COOLEST READINGS AROUND SPW.

ELEVATED CONVECTION IS EXPECTED TO CONTINUE TOMORROW
MORNING...PRIMARILY IN SW MN. LAPSE RATES AND MOISTURE WILL CONTINUE
TO INCREASE THROUGH THE MORNING ACROSS THE AREA. A VERY WARM LAYER
FROM 800 TO 700 HPA WILL BECOME ESTABLISHED OVER MUCH OF SE SD...NE
NEBRASKA...AND NW IA BY LATE MORNING WHICH IS EXPECTED TO SUPPRESS
CONVECTION IN THESE AREAS. HOWEVER...IF STORMS ARE ABLE TO DEVELOP
ON THE SW SIDE OF THE PRECIPITATION BAND OVER DURING THE MID TO LATE
MORNING...INCREASING CAPES...APPROACHING 1500 TO 2000 J/KG AND
SHEAR...APPROACHING 40 KTS...WOULD SUPPORT UP TO HALF DOLLAR SIZE
HAIL. BUT CONFIDENCE OF THIS HAPPENING IS LOW. THERE IS ANOTHER WAVE
MOVING FROM EAST CENTRAL SD INTO CENTRAL MN LATE WED AFTERNOON. AT
THIS POINT...THE BEST CHANCE FOR LATE AFTERNOON DEVELOPMENT WILL BE
ALONG AND EAST OF THE MINNESOTA RIVER. HOWEVER...IT IS POSSIBLE THAT
THE PRESENCE OF LEFT OVER OUTFLOW BOUNDARIES AND/OR DIFFERENTIAL
DIABATIC HEATING COULD RESULT IN A ONE OR TWO STORMS DEVELOPING IN
THE VICINITY OF MARSHALL. WHILE A VERY LOW PROBABILITY...LESS THAN
20 PERCENT...IF STORMS DO DEVELOP...THEY WOULD HAVE THE POTENTIAL TO
EVOLVE INTO SEVERE SUPERCELLS AS CAPES WOULD BE GREATER THAN 2000
J/KG AND EFFECTIVE SHEAR GREATER THAN 40 KTS. FOR NOW WILL HIGHLIGHT
THE LOW PROBABILITY OF SEVERE STORMS IN THE MORNING. HIGHS TOMORROW
ARE VERY DEPENDENT ON CLOUD COVER. WEST OF THE JAMES RIVER...EXPECT
HIGHS TO REACH THE LOW 90S WITH LOTS OF SUN...WHILE IN SW MN LOWER
80S ARE EXPECTED WITH CLOUDS MUCH OF THE DAY. WITH A STRONG
INVERSION IN PLACE...DEW POINTS WILL RISE INTO THE 70S RESULTING IN
HEAT INDICES OF 90 TO 100 DEGREES WEST OF I29 WEDNESDAY AFTERNOON.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CDT TUE SEP 2 2014

MODELS ARE IN PRETTY GOOD AGREEMENT THAT SURFACE LOW PRESSURE WILL
DEEPEN OVER CENTRAL SOUTH DAKOTA ON WEDNESDAY NIGHT...THEN RAPIDLY
LIFT NORTHEAST INTO NORTHERN MINNESOTA BY MIDDAY THURSDAY. A MID
LEVEL SHORTWAVE LIFTING INTO EAST CENTRAL MINNESOTA WILL ALLOW ANY
ISOLATED THUNDERSTORM ACTIVITY NEAR THE BUFFALO RIDGE AREA EARLY
WEDNESDAY EVENING TO EXIT THE FORECAST AREA QUICKLY. EARLY WEDNESDAY
NIGHT HOWEVER...A FAIRLY POTENT COLD FRONT DROPS INTO CENTRAL SOUTH
DAKOTA AND MOVES INTO THE JAMES VALLEY REGION LATE AT NIGHT.
SCATTERED TO ISOLATED SHOWERS WITH A FEW RUMBLES OF THUNDER WILL
DEVELOP ALONG AND JUST BEHIND THE FRONT. DID SPEED UP THE TIMING OF
THE FRONT SLIGHTLY...WHICH BRINGS IT INTO THE I29 CORRIDOR LATE
MORNING AND ACROSS OUR SOUTHEASTERN CWA THURSDAY LATE AFTERNOON.
STRONG CAPPING AND SOMEWHAT WEAK SUPPORT ATTENDING THE FRONT WILL
KEEP PRECIPITATION CHANCES LIMITED TO LOW END CHANCES FOR SHOWERS AND
NON SEVERE THUNDERSTORMS.

DRY AIR FILTERS INTO THE REGION THURSDAY NIGHT AS SURFACE HIGH
PRESSURE RAPIDLY EXPANDS INTO THE REGION. COOL AND DRY NORTHWEST
FLOW SETS UP FRIDAY INTO THE WEEKEND...LEADING TO SOME
PLEASANT...BUT UNSEASONABLY COOL WEATHER CONDITIONS. AFTERNOON HIGHS
ONLY TOP OUT IN THE UPPER 60S AND LOWER 70S ON FRIDAY AND
SATURDAY...AND IMPROVING A FEW DEGREES ON SUNDAY. OVERNIGHT LOWS
HAVE THE POTENTIAL TO BE QUITE COOL AS WELL WITH MOSTLY CLEAR SKIES
AND RELATIVELY LIGHT WINDS. LOWS SHOULD DROP INTO MID 40S TO LOW
50S...AND HAVE CONTINUED TO TREND BELOW THE ALLBLEND GUIDANCE.

MODELS SHOWING BETTER AGREEMENT THIS AFTERNOON REGARDING THE PATTERN
EVOLUTION EARLY NEXT WEEK. FLOW TURNS MORE ZONAL ON SUNDAY AND
SUNDAY EVENING...WITH A SOUTHERLY LOW LEVEL FETCH. THIS WILL ALLOW A
GREATER MOISTURE RETURN SUNDAY NIGHT INTO MONDAY NIGHT AHEAD OF THE
STRONG WAVE EMERGING FROM THE INTERMOUNTAIN WEST INTO CENTRAL HIGH
PLAINS MONDAY AFTERNOON. WITH WARM AIR ADVECTION AND INCREASED
MOISTURE...THUNDERSTORM CHANCES INCREASE MONDAY AND TUESDAY. MODELS
SUGGEST SOME CYCLOGENESIS FORMS IN THE VICINITY OF WESTERN SOUTH
DAKOTA EARLY TUESDAY. GIVEN THE DECENT AGREEMENT IN PLACEMENT
BETWEEN THE GFS AND ECMWF...AGREE WITH THE HIGH END CHANCE POPS FOR
MUCH OF THE FORECAST AREA. TEMPERATURES CONTINUE TO WARM A FEW
DURING THIS PERIOD...BUT SHOULD REMAIN NEAR OR JUST BELOW NORMAL.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1222 PM CDT TUE SEP 2 2014

MAIN ISSUE FOR TAFS ARE CONVECTION...POTENTIAL FOR LOW LEVEL WIND
SHEAR AND LOW CLOUDS. THROUGH 06Z WED...VFR CONDITIONS EXPECTED
ALTHOUGH WINDS WILL GRADUALLY BACK TO SOUTHEAST IN ALL LOCATION IN
THE EVENING. AFTER 06Z...A STRENGTHENING LOW LEVEL JET AND
INCREASING INSTABILITY ARE EXPECTED TO RESULT IN THE DEVELOPMENT
OF THUNDERSTORMS PRIOR TO DAWN. WHILE A STORM IS POSSIBLE IN KFSD
OR KHON...THE BEST CHANCE WILL BE IN SW MN. THEREFORE DID NOT
INCLUDE TSRA IN TAF FOR EITHER SITE. HOWEVER...WITH A 40 TO 50 KT
LOW LEVEL JET FROM SOUTHEAST SD IN SW MN LATE TONIGHT AND EARLY
THU MORNING...THERE IS THE POTENTIAL FOR NON CONVECTIVE LOW LEVEL
WIND SHEAR. WITH CORE OF THE JET GOING THROUGH THE KFSD AREA...DID
ADD LOW LEVEL WIND SHEAR FOR SIOUX FALLS...BUT SUBSEQUENT SHIFTS
WILL NEED TO EXAMINE POTENTIAL IN KHON. THE OTHER CONCERN IS
DEVELOPMENT OF MVFR CEILINGS WEDNESDAY MORNING. ALL MODELS SHOW
MOISTURE INCREASING BELOW A FAIRLY STRONG INVERSION SO EXPECT CIGS
FROM 1000 TO 2000 FT TO DEVELOP AT KFSD AND KSUX SHORTLY AFTER
SUNRISE. WITH LESS MOISTURE EXPECTED AT KHON...KEPT VFR CONDITIONS
FOR NOW.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...SCHUMACHER
LONG TERM...
AVIATION...SCHUMACHER





000
FXUS63 KFSD 021723
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1223 PM CDT TUE SEP 2 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CDT TUE SEP 2 2014

WAVE WILL EXIT TO OUR EAST THIS MORNING...GIVING WAY TO A MOSTLY
SUNNY DAY ACROSS THE REGION. TEMPERATURES ALOFT CONTINUE TO
WARM...BUT AS FLOW TURNS MORE SOUTHERLY...DO NOT THINK MIXING WILL
BE AS GOOD. EITHER WAY...MOST GUIDANCE SEEMS TOO LOW GIVEN MODEL 850
AND 925 MB TEMPERATURES...THUS CONTINUED ON THE WARM SIDE OF
GUIDANCE. LOOKING FOR UPPER 70S TO LOW 80S ACROSS THE AREA...WHICH
IS AROUND OR JUST ABOVE AVERAGE FOR THIS TIME OF YEAR.

LOW LEVEL JET PICKS UP TONIGHT...INCREASING THETA E ADVECTION AND
ISENTROPIC LIFT OVER THE REGION. INSTABILITY WILL INCREASE AS A
RESULT...ALTHOUGH EXPECT THE LOWER LEVELS TO REMAIN CAPPED AS
WARMER TEMPERATURES ALOFT ADVECT IN AS WELL. THUS LOOKING LIKE ANY
CONVECTIVE ACTIVITY WILL PROBABLY END UP BASED AROUND 800 MB OR
SO. MODEL CONSENSUS SUGGESTS BEST CHANCE OF SEEING SOME ELEVATED
SHOWER OR THUNDERSTORM ACTIVITY WILL BE ALONG AND NORTHEAST OF A
HURON TO SIOUX FALLS TO STORM LAKE LINE. BASED ON LOW LEVEL JET
LOCATION AND ORIENTATION THIS MAKES SENSE AS WELL...SO FOCUSED
POPS IN THIS AREA. THINK ACTIVITY WILL PROBABLY JUST REMAIN
ISOLATED TO SCATTERED BETWEEN 3 AM AND 7 AM. NAM SEEMS OVERDONE
WITH INSTABILITY ORIGINATING FROM 800 MB...SUGGESTING OVER 2000
J/KG. GFS AND ECMWF SOLUTIONS SEEM MORE REASONABLE...WITH 1000
J/KG OR LESS OF ELEVATED CAPE. STORMS WILL BE BASED ABOVE THE BEST
SHEAR AS WELL...SO OTHER THAN MAYBE SOME SMALL HAIL...WOULD NOT
EXPECT ANYTHING TOO STRONG THROUGH 12Z. WITH SOUTHERLY FLOW
INCREASING OVERNIGHT...WARMED LOWS A FEW DEGREES INTO THE LOW TO
MID 60S.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 403 AM CDT TUE SEP 2 2014

LIKELY THAT ISOLATED TO SCATTERED NOCTURNAL ELEVATED CONVECTION
WILL BE ONGOING AT THE START OF WEDNESDAY OVER THE NORTHEAST HALF
OF THE CWA. NAM SOLUTION REJECTED FOR SEVERAL REASONS...NOT THE
LEAST BEING SOME VERY UNREALISTIC THERMODYNAMIC PROFILES...WHICH
ARE ALLOWING A MUCH FURTHER SOUTH DEVELOPMENT INTO THE APPROACHING
CAP. WILL WATCH MID LEVEL FOCUS FOR THIS CONVECTION PULL OFF TO
THE NORTHEAST DURING THE DAY. OTHER ISSUE WITH WEDNESDAY WILL BE
THREAT FOR STRATUS DEVELOPMENT EARLY MORNING TO PERSIST LONGER
INTO THE DAY IN THE EAST TO GREATLY IMPACT TEMPERATURES. EAST OF
I 29 LIKELY TO SEE VERY LIMITED SUNSHINE INTO EARLY AFTERNOON...
PERHAPS EVEN A BIT MORE PESSIMISTIC THAN GOING FORECAST. AREAS TO
THE WEST WILL BE POISED TO HOLD ON TO OR BREAK OUT INTO SUNSHINE
MUCH EARLIER...WITH TEMPS VARYING FROM LOWER 80S EAST TO LOWER 90S
WEST BY AFTERNOON. VERY STRONG CAP INDICATED BY WEDNESDAY
AFTERNOON...SO HARD TO PICTURE BEING ABLE TO CONTINUE ANY THREAT
OF CONVECTION PAST A SMALL CHANCE MIDDAY FOR EVACUATING HIGH BASED
STORMS ON NOSE OF THE 7-9C/KM MID LEVEL LAPSE RATES.

STRONG PACIFIC NW WAVE WILL START TO KNOCK DOWN THE FLAT RIDGING
ACROSS THE NORTHERN PLAINS BY LATER WEDNESDAY NIGHT...WITH
CYCLOGENESIS ACROSS THE NORTHERN PLAINS...DRAGGING A FAIRLY STRONG
COLD FRONT TOWARD THE I 29 CORRIDOR BY EARLY THURSDAY MORNING.
BOUNDARY STRONGLY CAPPED AND CONVERGENCE LACKING...WITH DEEPER
DYNAMICAL LIFT FORCING LAGGING BEHIND WITH MID/HIGH LEVEL
MOISTURE. PROSPECT FOR ANY MEANINGFUL PRECIPITATION CHANCES ON
LATER THURSDAY AND THURSDAY NIGHT ARE REALLY NOT THERE...WITH JUST
A MINIMAL THREAT FOR A HIGHER BASED SHOWER OR EVEN LESS LIKELY A
THUNDERSTORM ALONG WITH DIV Q AXIS SLIPPING SOUTHEASTWARD BEHIND
BOUNDARY. LOW LEVEL FRONTAL BOUNDARY IS VERY WELL REMOVED TO THE
SOUTH OF THE AREA BY LATER AFTERNOON...WITH PERHAPS THE LEADING
HINT OF LOWER BASED DEVELOPMENT BY VERY LATE AFTERNOON OR EARLY
EVENING ALONG THE FAR SOUTHEAST CORNER OF THE CWA.

THE PERIOD FROM FRIDAY THROUGH SUNDAY WILL TRANSITION BACK TO
NORTHWESTERLY FLOW...WITH A LARGE COOL AREA OF HIGH PRESSURE
SETTLING THROUGH THE NORTHERN PLAINS. THIS WILL DRIVE BOUNDARY
SOUTHWARD...AND OTHER THAN A REMOTE CHANCE FOR A HIGH PLAINS
DEVELOPMENT TO BRUSH THE FAR SOUTHWEST CWA WITH AN ILL-TIMED
WEAK WAVE AROUND FRIDAY OR SATURDAY...WILL BE DRY AND QUITE
COOL...WITH HIGHS IN THE UPPER 60S TO LOWER 70S...AND LOWS IN
THE MID 40S TO LOWER 50S.

TRANSITION BACK TOWARD ZONAL TO WEAKLY SOUTHWEST FLOW TOWARD THE
END OF THE PERIOD...WITH LOW LEVEL SOUTHERLY FLOW INCREASING ALONG
WITH MOISTURE CONTENT OF AIR. WITH NORTHERN STREAM WAVE INDUCING
INCREASE LOWER TO MID LEVEL THETA E ADVECTION BY SUNDAY NIGHT AND
MONDAY...CONTINUED TO INDICATE A LOWER CHANCE FOR THUNDERSTORMS.
TEMPS START TO MODERATE WITH MORE CLOUDS AND INCREASED MOISTURE...
BUT STILL REMAIN BELOW NORMAL THROUGH MONDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1222 PM CDT TUE SEP 2 2014

MAIN ISSUE FOR TAFS ARE CONVECTION...POTENTIAL FOR LOW LEVEL WIND
SHEAR AND LOW CLOUDS. THROUGH 06Z WED...VFR CONDITIONS EXPECTED
ALTHOUGH WINDS WILL GRADUALLY BACK TO SOUTHEAST IN ALL LOCATION IN
THE EVENING. AFTER 06Z...A STRENGTHENING LOW LEVEL JET AND
INCREASING INSTABILITY ARE EXPECTED TO RESULT IN THE DEVELOPMENT
OF THUNDERSTORMS PRIOR TO DAWN. WHILE A STORM IS POSSIBLE IN KFSD
OR KHON...THE BEST CHANCE WILL BE IN SW MN. THEREFORE DID NOT
INCLUDE TSRA IN TAF FOR EITHER SITE. HOWEVER...WITH A 40 TO 50 KT
LOW LEVEL JET FROM SOUTHEAST SD IN SW MN LATE TONIGHT AND EARLY
THU MORNING...THERE IS THE POTENTIAL FOR NON CONVECTIVE LOW LEVEL
WIND SHEAR. WITH CORE OF THE JET GOING THROUGH THE KFSD AREA...DID
ADD LOW LEVEL WIND SHEAR FOR SIOUX FALLS...BUT SUBSEQUENT SHIFTS
WILL NEED TO EXAMINE POTENTIAL IN KHON. THE OTHER CONCERN IS
DEVELOPMENT OF MVFR CEILINGS WEDNESDAY MORNING. ALL MODELS SHOW
MOISTURE INCREASING BELOW A FAIRLY STRONG INVERSION SO EXPECT CIGS
FROM 1000 TO 2000 FT TO DEVELOP AT KFSD AND KSUX SHORTLY AFTER
SUNRISE. WITH LESS MOISTURE EXPECTED AT KHON...KEPT VFR CONDITIONS
FOR NOW.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...SCHUMACHER





000
FXUS63 KFSD 021723
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1223 PM CDT TUE SEP 2 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CDT TUE SEP 2 2014

WAVE WILL EXIT TO OUR EAST THIS MORNING...GIVING WAY TO A MOSTLY
SUNNY DAY ACROSS THE REGION. TEMPERATURES ALOFT CONTINUE TO
WARM...BUT AS FLOW TURNS MORE SOUTHERLY...DO NOT THINK MIXING WILL
BE AS GOOD. EITHER WAY...MOST GUIDANCE SEEMS TOO LOW GIVEN MODEL 850
AND 925 MB TEMPERATURES...THUS CONTINUED ON THE WARM SIDE OF
GUIDANCE. LOOKING FOR UPPER 70S TO LOW 80S ACROSS THE AREA...WHICH
IS AROUND OR JUST ABOVE AVERAGE FOR THIS TIME OF YEAR.

LOW LEVEL JET PICKS UP TONIGHT...INCREASING THETA E ADVECTION AND
ISENTROPIC LIFT OVER THE REGION. INSTABILITY WILL INCREASE AS A
RESULT...ALTHOUGH EXPECT THE LOWER LEVELS TO REMAIN CAPPED AS
WARMER TEMPERATURES ALOFT ADVECT IN AS WELL. THUS LOOKING LIKE ANY
CONVECTIVE ACTIVITY WILL PROBABLY END UP BASED AROUND 800 MB OR
SO. MODEL CONSENSUS SUGGESTS BEST CHANCE OF SEEING SOME ELEVATED
SHOWER OR THUNDERSTORM ACTIVITY WILL BE ALONG AND NORTHEAST OF A
HURON TO SIOUX FALLS TO STORM LAKE LINE. BASED ON LOW LEVEL JET
LOCATION AND ORIENTATION THIS MAKES SENSE AS WELL...SO FOCUSED
POPS IN THIS AREA. THINK ACTIVITY WILL PROBABLY JUST REMAIN
ISOLATED TO SCATTERED BETWEEN 3 AM AND 7 AM. NAM SEEMS OVERDONE
WITH INSTABILITY ORIGINATING FROM 800 MB...SUGGESTING OVER 2000
J/KG. GFS AND ECMWF SOLUTIONS SEEM MORE REASONABLE...WITH 1000
J/KG OR LESS OF ELEVATED CAPE. STORMS WILL BE BASED ABOVE THE BEST
SHEAR AS WELL...SO OTHER THAN MAYBE SOME SMALL HAIL...WOULD NOT
EXPECT ANYTHING TOO STRONG THROUGH 12Z. WITH SOUTHERLY FLOW
INCREASING OVERNIGHT...WARMED LOWS A FEW DEGREES INTO THE LOW TO
MID 60S.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 403 AM CDT TUE SEP 2 2014

LIKELY THAT ISOLATED TO SCATTERED NOCTURNAL ELEVATED CONVECTION
WILL BE ONGOING AT THE START OF WEDNESDAY OVER THE NORTHEAST HALF
OF THE CWA. NAM SOLUTION REJECTED FOR SEVERAL REASONS...NOT THE
LEAST BEING SOME VERY UNREALISTIC THERMODYNAMIC PROFILES...WHICH
ARE ALLOWING A MUCH FURTHER SOUTH DEVELOPMENT INTO THE APPROACHING
CAP. WILL WATCH MID LEVEL FOCUS FOR THIS CONVECTION PULL OFF TO
THE NORTHEAST DURING THE DAY. OTHER ISSUE WITH WEDNESDAY WILL BE
THREAT FOR STRATUS DEVELOPMENT EARLY MORNING TO PERSIST LONGER
INTO THE DAY IN THE EAST TO GREATLY IMPACT TEMPERATURES. EAST OF
I 29 LIKELY TO SEE VERY LIMITED SUNSHINE INTO EARLY AFTERNOON...
PERHAPS EVEN A BIT MORE PESSIMISTIC THAN GOING FORECAST. AREAS TO
THE WEST WILL BE POISED TO HOLD ON TO OR BREAK OUT INTO SUNSHINE
MUCH EARLIER...WITH TEMPS VARYING FROM LOWER 80S EAST TO LOWER 90S
WEST BY AFTERNOON. VERY STRONG CAP INDICATED BY WEDNESDAY
AFTERNOON...SO HARD TO PICTURE BEING ABLE TO CONTINUE ANY THREAT
OF CONVECTION PAST A SMALL CHANCE MIDDAY FOR EVACUATING HIGH BASED
STORMS ON NOSE OF THE 7-9C/KM MID LEVEL LAPSE RATES.

STRONG PACIFIC NW WAVE WILL START TO KNOCK DOWN THE FLAT RIDGING
ACROSS THE NORTHERN PLAINS BY LATER WEDNESDAY NIGHT...WITH
CYCLOGENESIS ACROSS THE NORTHERN PLAINS...DRAGGING A FAIRLY STRONG
COLD FRONT TOWARD THE I 29 CORRIDOR BY EARLY THURSDAY MORNING.
BOUNDARY STRONGLY CAPPED AND CONVERGENCE LACKING...WITH DEEPER
DYNAMICAL LIFT FORCING LAGGING BEHIND WITH MID/HIGH LEVEL
MOISTURE. PROSPECT FOR ANY MEANINGFUL PRECIPITATION CHANCES ON
LATER THURSDAY AND THURSDAY NIGHT ARE REALLY NOT THERE...WITH JUST
A MINIMAL THREAT FOR A HIGHER BASED SHOWER OR EVEN LESS LIKELY A
THUNDERSTORM ALONG WITH DIV Q AXIS SLIPPING SOUTHEASTWARD BEHIND
BOUNDARY. LOW LEVEL FRONTAL BOUNDARY IS VERY WELL REMOVED TO THE
SOUTH OF THE AREA BY LATER AFTERNOON...WITH PERHAPS THE LEADING
HINT OF LOWER BASED DEVELOPMENT BY VERY LATE AFTERNOON OR EARLY
EVENING ALONG THE FAR SOUTHEAST CORNER OF THE CWA.

THE PERIOD FROM FRIDAY THROUGH SUNDAY WILL TRANSITION BACK TO
NORTHWESTERLY FLOW...WITH A LARGE COOL AREA OF HIGH PRESSURE
SETTLING THROUGH THE NORTHERN PLAINS. THIS WILL DRIVE BOUNDARY
SOUTHWARD...AND OTHER THAN A REMOTE CHANCE FOR A HIGH PLAINS
DEVELOPMENT TO BRUSH THE FAR SOUTHWEST CWA WITH AN ILL-TIMED
WEAK WAVE AROUND FRIDAY OR SATURDAY...WILL BE DRY AND QUITE
COOL...WITH HIGHS IN THE UPPER 60S TO LOWER 70S...AND LOWS IN
THE MID 40S TO LOWER 50S.

TRANSITION BACK TOWARD ZONAL TO WEAKLY SOUTHWEST FLOW TOWARD THE
END OF THE PERIOD...WITH LOW LEVEL SOUTHERLY FLOW INCREASING ALONG
WITH MOISTURE CONTENT OF AIR. WITH NORTHERN STREAM WAVE INDUCING
INCREASE LOWER TO MID LEVEL THETA E ADVECTION BY SUNDAY NIGHT AND
MONDAY...CONTINUED TO INDICATE A LOWER CHANCE FOR THUNDERSTORMS.
TEMPS START TO MODERATE WITH MORE CLOUDS AND INCREASED MOISTURE...
BUT STILL REMAIN BELOW NORMAL THROUGH MONDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1222 PM CDT TUE SEP 2 2014

MAIN ISSUE FOR TAFS ARE CONVECTION...POTENTIAL FOR LOW LEVEL WIND
SHEAR AND LOW CLOUDS. THROUGH 06Z WED...VFR CONDITIONS EXPECTED
ALTHOUGH WINDS WILL GRADUALLY BACK TO SOUTHEAST IN ALL LOCATION IN
THE EVENING. AFTER 06Z...A STRENGTHENING LOW LEVEL JET AND
INCREASING INSTABILITY ARE EXPECTED TO RESULT IN THE DEVELOPMENT
OF THUNDERSTORMS PRIOR TO DAWN. WHILE A STORM IS POSSIBLE IN KFSD
OR KHON...THE BEST CHANCE WILL BE IN SW MN. THEREFORE DID NOT
INCLUDE TSRA IN TAF FOR EITHER SITE. HOWEVER...WITH A 40 TO 50 KT
LOW LEVEL JET FROM SOUTHEAST SD IN SW MN LATE TONIGHT AND EARLY
THU MORNING...THERE IS THE POTENTIAL FOR NON CONVECTIVE LOW LEVEL
WIND SHEAR. WITH CORE OF THE JET GOING THROUGH THE KFSD AREA...DID
ADD LOW LEVEL WIND SHEAR FOR SIOUX FALLS...BUT SUBSEQUENT SHIFTS
WILL NEED TO EXAMINE POTENTIAL IN KHON. THE OTHER CONCERN IS
DEVELOPMENT OF MVFR CEILINGS WEDNESDAY MORNING. ALL MODELS SHOW
MOISTURE INCREASING BELOW A FAIRLY STRONG INVERSION SO EXPECT CIGS
FROM 1000 TO 2000 FT TO DEVELOP AT KFSD AND KSUX SHORTLY AFTER
SUNRISE. WITH LESS MOISTURE EXPECTED AT KHON...KEPT VFR CONDITIONS
FOR NOW.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...SCHUMACHER




000
FXUS63 KFSD 021133
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
633 AM CDT TUE SEP 2 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CDT TUE SEP 2 2014

WAVE WILL EXIT TO OUR EAST THIS MORNING...GIVING WAY TO A MOSTLY
SUNNY DAY ACROSS THE REGION. TEMPERATURES ALOFT CONTINUE TO
WARM...BUT AS FLOW TURNS MORE SOUTHERLY...DO NOT THINK MIXING WILL
BE AS GOOD. EITHER WAY...MOST GUIDANCE SEEMS TOO LOW GIVEN MODEL 850
AND 925 MB TEMPERATURES...THUS CONTINUED ON THE WARM SIDE OF
GUIDANCE. LOOKING FOR UPPER 70S TO LOW 80S ACROSS THE AREA...WHICH
IS AROUND OR JUST ABOVE AVERAGE FOR THIS TIME OF YEAR.

LOW LEVEL JET PICKS UP TONIGHT...INCREASING THETA E ADVECTION AND
ISENTROPIC LIFT OVER THE REGION. INSTABILITY WILL INCREASE AS A
RESULT...ALTHOUGH EXPECT THE LOWER LEVELS TO REMAIN CAPPED AS
WARMER TEMPERATURES ALOFT ADVECT IN AS WELL. THUS LOOKING LIKE ANY
CONVECTIVE ACTIVITY WILL PROBABLY END UP BASED AROUND 800 MB OR
SO. MODEL CONSENSUS SUGGESTS BEST CHANCE OF SEEING SOME ELEVATED
SHOWER OR THUNDERSTORM ACTIVITY WILL BE ALONG AND NORTHEAST OF A
HURON TO SIOUX FALLS TO STORM LAKE LINE. BASED ON LOW LEVEL JET
LOCATION AND ORIENTATION THIS MAKES SENSE AS WELL...SO FOCUSED
POPS IN THIS AREA. THINK ACTIVITY WILL PROBABLY JUST REMAIN
ISOLATED TO SCATTERED BETWEEN 3 AM AND 7 AM. NAM SEEMS OVERDONE
WITH INSTABILITY ORIGINATING FROM 800 MB...SUGGESTING OVER 2000
J/KG. GFS AND ECMWF SOLUTIONS SEEM MORE REASONABLE...WITH 1000
J/KG OR LESS OF ELEVATED CAPE. STORMS WILL BE BASED ABOVE THE BEST
SHEAR AS WELL...SO OTHER THAN MAYBE SOME SMALL HAIL...WOULD NOT
EXPECT ANYTHING TOO STRONG THROUGH 12Z. WITH SOUTHERLY FLOW
INCREASING OVERNIGHT...WARMED LOWS A FEW DEGREES INTO THE LOW TO
MID 60S.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 403 AM CDT TUE SEP 2 2014

LIKELY THAT ISOLATED TO SCATTERED NOCTURNAL ELEVATED CONVECTION
WILL BE ONGOING AT THE START OF WEDNESDAY OVER THE NORTHEAST HALF
OF THE CWA. NAM SOLUTION REJECTED FOR SEVERAL REASONS...NOT THE
LEAST BEING SOME VERY UNREALISTIC THERMODYNAMIC PROFILES...WHICH
ARE ALLOWING A MUCH FURTHER SOUTH DEVELOPMENT INTO THE APPROACHING
CAP. WILL WATCH MID LEVEL FOCUS FOR THIS CONVECTION PULL OFF TO
THE NORTHEAST DURING THE DAY. OTHER ISSUE WITH WEDNESDAY WILL BE
THREAT FOR STRATUS DEVELOPMENT EARLY MORNING TO PERSIST LONGER
INTO THE DAY IN THE EAST TO GREATLY IMPACT TEMPERATURES. EAST OF
I 29 LIKELY TO SEE VERY LIMITED SUNSHINE INTO EARLY AFTERNOON...
PERHAPS EVEN A BIT MORE PESSIMISTIC THAN GOING FORECAST. AREAS TO
THE WEST WILL BE POISED TO HOLD ON TO OR BREAK OUT INTO SUNSHINE
MUCH EARLIER...WITH TEMPS VARYING FROM LOWER 80S EAST TO LOWER 90S
WEST BY AFTERNOON. VERY STRONG CAP INDICATED BY WEDNESDAY
AFTERNOON...SO HARD TO PICTURE BEING ABLE TO CONTINUE ANY THREAT
OF CONVECTION PAST A SMALL CHANCE MIDDAY FOR EVACUATING HIGH BASED
STORMS ON NOSE OF THE 7-9C/KM MID LEVEL LAPSE RATES.

STRONG PACIFIC NW WAVE WILL START TO KNOCK DOWN THE FLAT RIDGING
ACROSS THE NORTHERN PLAINS BY LATER WEDNESDAY NIGHT...WITH
CYCLOGENESIS ACROSS THE NORTHERN PLAINS...DRAGGING A FAIRLY STRONG
COLD FRONT TOWARD THE I 29 CORRIDOR BY EARLY THURSDAY MORNING.
BOUNDARY STRONGLY CAPPED AND CONVERGENCE LACKING...WITH DEEPER
DYNAMICAL LIFT FORCING LAGGING BEHIND WITH MID/HIGH LEVEL
MOISTURE. PROSPECT FOR ANY MEANINGFUL PRECIPITATION CHANCES ON
LATER THURSDAY AND THURSDAY NIGHT ARE REALLY NOT THERE...WITH JUST
A MINIMAL THREAT FOR A HIGHER BASED SHOWER OR EVEN LESS LIKELY A
THUNDERSTORM ALONG WITH DIV Q AXIS SLIPPING SOUTHEASTWARD BEHIND
BOUNDARY. LOW LEVEL FRONTAL BOUNDARY IS VERY WELL REMOVED TO THE
SOUTH OF THE AREA BY LATER AFTERNOON...WITH PERHAPS THE LEADING
HINT OF LOWER BASED DEVELOPMENT BY VERY LATE AFTERNOON OR EARLY
EVENING ALONG THE FAR SOUTHEAST CORNER OF THE CWA.

THE PERIOD FROM FRIDAY THROUGH SUNDAY WILL TRANSITION BACK TO
NORTHWESTERLY FLOW...WITH A LARGE COOL AREA OF HIGH PRESSURE
SETTLING THROUGH THE NORTHERN PLAINS. THIS WILL DRIVE BOUNDARY
SOUTHWARD...AND OTHER THAN A REMOTE CHANCE FOR A HIGH PLAINS
DEVELOPMENT TO BRUSH THE FAR SOUTHWEST CWA WITH AN ILL-TIMED
WEAK WAVE AROUND FRIDAY OR SATURDAY...WILL BE DRY AND QUITE
COOL...WITH HIGHS IN THE UPPER 60S TO LOWER 70S...AND LOWS IN
THE MID 40S TO LOWER 50S.

TRANSITION BACK TOWARD ZONAL TO WEAKLY SOUTHWEST FLOW TOWARD THE
END OF THE PERIOD...WITH LOW LEVEL SOUTHERLY FLOW INCREASING ALONG
WITH MOISTURE CONTENT OF AIR. WITH NORTHERN STREAM WAVE INDUCING
INCREASE LOWER TO MID LEVEL THETA E ADVECTION BY SUNDAY NIGHT AND
MONDAY...CONTINUED TO INDICATE A LOWER CHANCE FOR THUNDERSTORMS.
TEMPS START TO MODERATE WITH MORE CLOUDS AND INCREASED MOISTURE...
BUT STILL REMAIN BELOW NORMAL THROUGH MONDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 628 AM CDT TUE SEP 2 2014

VFR CONDITIONS EXPECTED TODAY. LATER TONIGHT...COULD SEE ISOLATED
TO SCATTERED THUNDERSTORMS...MAINLY ALONG AND NORTHEAST OF A HURON
TO SIOUX FALLS TO STORM LAKE LINE. HOWEVER COVERAGE IS EXPECTED TO
BE TOO LOW TO INCLUDE IN TAFS AT THIS TIME. ALSO WILL HAVE TO
WATCH THE LOW LEVEL JET TONIGHT. COULD BE NEAR LLWS AT KHON...BUT
CURRENTLY LOOKS LIKE IT MAY STAY JUST SHORT. THIS INCREASING
SOUTHERLY FLOW WILL ALSO ADVECT MOISTURE NORTH...AND COULD HAVE
SOME LOW STRATUS OR FOG BY MORNING. ALTHOUGH AT THIS TIME LOOKS
LIKE PROBABILITY OF THIS THROUGH 12Z IS LOW ENOUGH TO KEEP OUT OF
THE TAFS...BUT FUTURE SHIFTS WILL HAVE TO MONITOR MODEL TRENDS.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...CHENARD




000
FXUS63 KFSD 021133
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
633 AM CDT TUE SEP 2 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CDT TUE SEP 2 2014

WAVE WILL EXIT TO OUR EAST THIS MORNING...GIVING WAY TO A MOSTLY
SUNNY DAY ACROSS THE REGION. TEMPERATURES ALOFT CONTINUE TO
WARM...BUT AS FLOW TURNS MORE SOUTHERLY...DO NOT THINK MIXING WILL
BE AS GOOD. EITHER WAY...MOST GUIDANCE SEEMS TOO LOW GIVEN MODEL 850
AND 925 MB TEMPERATURES...THUS CONTINUED ON THE WARM SIDE OF
GUIDANCE. LOOKING FOR UPPER 70S TO LOW 80S ACROSS THE AREA...WHICH
IS AROUND OR JUST ABOVE AVERAGE FOR THIS TIME OF YEAR.

LOW LEVEL JET PICKS UP TONIGHT...INCREASING THETA E ADVECTION AND
ISENTROPIC LIFT OVER THE REGION. INSTABILITY WILL INCREASE AS A
RESULT...ALTHOUGH EXPECT THE LOWER LEVELS TO REMAIN CAPPED AS
WARMER TEMPERATURES ALOFT ADVECT IN AS WELL. THUS LOOKING LIKE ANY
CONVECTIVE ACTIVITY WILL PROBABLY END UP BASED AROUND 800 MB OR
SO. MODEL CONSENSUS SUGGESTS BEST CHANCE OF SEEING SOME ELEVATED
SHOWER OR THUNDERSTORM ACTIVITY WILL BE ALONG AND NORTHEAST OF A
HURON TO SIOUX FALLS TO STORM LAKE LINE. BASED ON LOW LEVEL JET
LOCATION AND ORIENTATION THIS MAKES SENSE AS WELL...SO FOCUSED
POPS IN THIS AREA. THINK ACTIVITY WILL PROBABLY JUST REMAIN
ISOLATED TO SCATTERED BETWEEN 3 AM AND 7 AM. NAM SEEMS OVERDONE
WITH INSTABILITY ORIGINATING FROM 800 MB...SUGGESTING OVER 2000
J/KG. GFS AND ECMWF SOLUTIONS SEEM MORE REASONABLE...WITH 1000
J/KG OR LESS OF ELEVATED CAPE. STORMS WILL BE BASED ABOVE THE BEST
SHEAR AS WELL...SO OTHER THAN MAYBE SOME SMALL HAIL...WOULD NOT
EXPECT ANYTHING TOO STRONG THROUGH 12Z. WITH SOUTHERLY FLOW
INCREASING OVERNIGHT...WARMED LOWS A FEW DEGREES INTO THE LOW TO
MID 60S.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 403 AM CDT TUE SEP 2 2014

LIKELY THAT ISOLATED TO SCATTERED NOCTURNAL ELEVATED CONVECTION
WILL BE ONGOING AT THE START OF WEDNESDAY OVER THE NORTHEAST HALF
OF THE CWA. NAM SOLUTION REJECTED FOR SEVERAL REASONS...NOT THE
LEAST BEING SOME VERY UNREALISTIC THERMODYNAMIC PROFILES...WHICH
ARE ALLOWING A MUCH FURTHER SOUTH DEVELOPMENT INTO THE APPROACHING
CAP. WILL WATCH MID LEVEL FOCUS FOR THIS CONVECTION PULL OFF TO
THE NORTHEAST DURING THE DAY. OTHER ISSUE WITH WEDNESDAY WILL BE
THREAT FOR STRATUS DEVELOPMENT EARLY MORNING TO PERSIST LONGER
INTO THE DAY IN THE EAST TO GREATLY IMPACT TEMPERATURES. EAST OF
I 29 LIKELY TO SEE VERY LIMITED SUNSHINE INTO EARLY AFTERNOON...
PERHAPS EVEN A BIT MORE PESSIMISTIC THAN GOING FORECAST. AREAS TO
THE WEST WILL BE POISED TO HOLD ON TO OR BREAK OUT INTO SUNSHINE
MUCH EARLIER...WITH TEMPS VARYING FROM LOWER 80S EAST TO LOWER 90S
WEST BY AFTERNOON. VERY STRONG CAP INDICATED BY WEDNESDAY
AFTERNOON...SO HARD TO PICTURE BEING ABLE TO CONTINUE ANY THREAT
OF CONVECTION PAST A SMALL CHANCE MIDDAY FOR EVACUATING HIGH BASED
STORMS ON NOSE OF THE 7-9C/KM MID LEVEL LAPSE RATES.

STRONG PACIFIC NW WAVE WILL START TO KNOCK DOWN THE FLAT RIDGING
ACROSS THE NORTHERN PLAINS BY LATER WEDNESDAY NIGHT...WITH
CYCLOGENESIS ACROSS THE NORTHERN PLAINS...DRAGGING A FAIRLY STRONG
COLD FRONT TOWARD THE I 29 CORRIDOR BY EARLY THURSDAY MORNING.
BOUNDARY STRONGLY CAPPED AND CONVERGENCE LACKING...WITH DEEPER
DYNAMICAL LIFT FORCING LAGGING BEHIND WITH MID/HIGH LEVEL
MOISTURE. PROSPECT FOR ANY MEANINGFUL PRECIPITATION CHANCES ON
LATER THURSDAY AND THURSDAY NIGHT ARE REALLY NOT THERE...WITH JUST
A MINIMAL THREAT FOR A HIGHER BASED SHOWER OR EVEN LESS LIKELY A
THUNDERSTORM ALONG WITH DIV Q AXIS SLIPPING SOUTHEASTWARD BEHIND
BOUNDARY. LOW LEVEL FRONTAL BOUNDARY IS VERY WELL REMOVED TO THE
SOUTH OF THE AREA BY LATER AFTERNOON...WITH PERHAPS THE LEADING
HINT OF LOWER BASED DEVELOPMENT BY VERY LATE AFTERNOON OR EARLY
EVENING ALONG THE FAR SOUTHEAST CORNER OF THE CWA.

THE PERIOD FROM FRIDAY THROUGH SUNDAY WILL TRANSITION BACK TO
NORTHWESTERLY FLOW...WITH A LARGE COOL AREA OF HIGH PRESSURE
SETTLING THROUGH THE NORTHERN PLAINS. THIS WILL DRIVE BOUNDARY
SOUTHWARD...AND OTHER THAN A REMOTE CHANCE FOR A HIGH PLAINS
DEVELOPMENT TO BRUSH THE FAR SOUTHWEST CWA WITH AN ILL-TIMED
WEAK WAVE AROUND FRIDAY OR SATURDAY...WILL BE DRY AND QUITE
COOL...WITH HIGHS IN THE UPPER 60S TO LOWER 70S...AND LOWS IN
THE MID 40S TO LOWER 50S.

TRANSITION BACK TOWARD ZONAL TO WEAKLY SOUTHWEST FLOW TOWARD THE
END OF THE PERIOD...WITH LOW LEVEL SOUTHERLY FLOW INCREASING ALONG
WITH MOISTURE CONTENT OF AIR. WITH NORTHERN STREAM WAVE INDUCING
INCREASE LOWER TO MID LEVEL THETA E ADVECTION BY SUNDAY NIGHT AND
MONDAY...CONTINUED TO INDICATE A LOWER CHANCE FOR THUNDERSTORMS.
TEMPS START TO MODERATE WITH MORE CLOUDS AND INCREASED MOISTURE...
BUT STILL REMAIN BELOW NORMAL THROUGH MONDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 628 AM CDT TUE SEP 2 2014

VFR CONDITIONS EXPECTED TODAY. LATER TONIGHT...COULD SEE ISOLATED
TO SCATTERED THUNDERSTORMS...MAINLY ALONG AND NORTHEAST OF A HURON
TO SIOUX FALLS TO STORM LAKE LINE. HOWEVER COVERAGE IS EXPECTED TO
BE TOO LOW TO INCLUDE IN TAFS AT THIS TIME. ALSO WILL HAVE TO
WATCH THE LOW LEVEL JET TONIGHT. COULD BE NEAR LLWS AT KHON...BUT
CURRENTLY LOOKS LIKE IT MAY STAY JUST SHORT. THIS INCREASING
SOUTHERLY FLOW WILL ALSO ADVECT MOISTURE NORTH...AND COULD HAVE
SOME LOW STRATUS OR FOG BY MORNING. ALTHOUGH AT THIS TIME LOOKS
LIKE PROBABILITY OF THIS THROUGH 12Z IS LOW ENOUGH TO KEEP OUT OF
THE TAFS...BUT FUTURE SHIFTS WILL HAVE TO MONITOR MODEL TRENDS.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...CHENARD





000
FXUS63 KFSD 020903
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
403 AM CDT TUE SEP 2 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CDT TUE SEP 2 2014

WAVE WILL EXIT TO OUR EAST THIS MORNING...GIVING WAY TO A MOSTLY
SUNNY DAY ACROSS THE REGION. TEMPERATURES ALOFT CONTINUE TO
WARM...BUT AS FLOW TURNS MORE SOUTHERLY...DO NOT THINK MIXING WILL
BE AS GOOD. EITHER WAY...MOST GUIDANCE SEEMS TOO LOW GIVEN MODEL 850
AND 925 MB TEMPERATURES...THUS CONTINUED ON THE WARM SIDE OF
GUIDANCE. LOOKING FOR UPPER 70S TO LOW 80S ACROSS THE AREA...WHICH
IS AROUND OR JUST ABOVE AVERAGE FOR THIS TIME OF YEAR.

LOW LEVEL JET PICKS UP TONIGHT...INCREASING THETA E ADVECTION AND
ISENTROPIC LIFT OVER THE REGION. INSTABILITY WILL INCREASE AS A
RESULT...ALTHOUGH EXPECT THE LOWER LEVELS TO REMAIN CAPPED AS
WARMER TEMPERATURES ALOFT ADVECT IN AS WELL. THUS LOOKING LIKE ANY
CONVECTIVE ACTIVITY WILL PROBABLY END UP BASED AROUND 800 MB OR
SO. MODEL CONSENSUS SUGGESTS BEST CHANCE OF SEEING SOME ELEVATED
SHOWER OR THUNDERSTORM ACTIVITY WILL BE ALONG AND NORTHEAST OF A
HURON TO SIOUX FALLS TO STORM LAKE LINE. BASED ON LOW LEVEL JET
LOCATION AND ORIENTATION THIS MAKES SENSE AS WELL...SO FOCUSED
POPS IN THIS AREA. THINK ACTIVITY WILL PROBABLY JUST REMAIN
ISOLATED TO SCATTERED BETWEEN 3 AM AND 7 AM. NAM SEEMS OVERDONE
WITH INSTABILITY ORIGINATING FROM 800 MB...SUGGESTING OVER 2000
J/KG. GFS AND ECMWF SOLUTIONS SEEM MORE REASONABLE...WITH 1000
J/KG OR LESS OF ELEVATED CAPE. STORMS WILL BE BASED ABOVE THE BEST
SHEAR AS WELL...SO OTHER THAN MAYBE SOME SMALL HAIL...WOULD NOT
EXPECT ANYTHING TOO STRONG THROUGH 12Z. WITH SOUTHERLY FLOW
INCREASING OVERNIGHT...WARMED LOWS A FEW DEGREES INTO THE LOW TO
MID 60S.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 403 AM CDT TUE SEP 2 2014

LIKELY THAT ISOLATED TO SCATTERED NOCTURNAL ELEVATED CONVECTION
WILL BE ONGOING AT THE START OF WEDNESDAY OVER THE NORTHEAST HALF
OF THE CWA. NAM SOLUTION REJECTED FOR SEVERAL REASONS...NOT THE
LEAST BEING SOME VERY UNREALISTIC THERMODYNAMIC PROFILES...WHICH
ARE ALLOWING A MUCH FURTHER SOUTH DEVELOPMENT INTO THE APPROACHING
CAP. WILL WATCH MID LEVEL FOCUS FOR THIS CONVECTION PULL OFF TO
THE NORTHEAST DURING THE DAY. OTHER ISSUE WITH WEDNESDAY WILL BE
THREAT FOR STRATUS DEVELOPMENT EARLY MORNING TO PERSIST LONGER
INTO THE DAY IN THE EAST TO GREATLY IMPACT TEMPERATURES. EAST OF
I 29 LIKELY TO SEE VERY LIMITED SUNSHINE INTO EARLY AFTERNOON...
PERHAPS EVEN A BIT MORE PESSIMISTIC THAN GOING FORECAST. AREAS TO
THE WEST WILL BE POISED TO HOLD ON TO OR BREAK OUT INTO SUNSHINE
MUCH EARLIER...WITH TEMPS VARYING FROM LOWER 80S EAST TO LOWER 90S
WEST BY AFTERNOON. VERY STRONG CAP INDICATED BY WEDNESDAY
AFTERNOON...SO HARD TO PICTURE BEING ABLE TO CONTINUE ANY THREAT
OF CONVECTION PAST A SMALL CHANCE MIDDAY FOR EVACUATING HIGH BASED
STORMS ON NOSE OF THE 7-9C/KM MID LEVEL LAPSE RATES.

STRONG PACIFIC NW WAVE WILL START TO KNOCK DOWN THE FLAT RIDGING
ACROSS THE NORTHERN PLAINS BY LATER WEDNESDAY NIGHT...WITH
CYCLOGENESIS ACROSS THE NORTHERN PLAINS...DRAGGING A FAIRLY STRONG
COLD FRONT TOWARD THE I 29 CORRIDOR BY EARLY THURSDAY MORNING.
BOUNDARY STRONGLY CAPPED AND CONVERGENCE LACKING...WITH DEEPER
DYNAMICAL LIFT FORCING LAGGING BEHIND WITH MID/HIGH LEVEL
MOISTURE. PROSPECT FOR ANY MEANINGFUL PRECIPITATION CHANCES ON
LATER THURSDAY AND THURSDAY NIGHT ARE REALLY NOT THERE...WITH JUST
A MINIMAL THREAT FOR A HIGHER BASED SHOWER OR EVEN LESS LIKELY A
THUNDERSTORM ALONG WITH DIV Q AXIS SLIPPING SOUTHEASTWARD BEHIND
BOUNDARY. LOW LEVEL FRONTAL BOUNDARY IS VERY WELL REMOVED TO THE
SOUTH OF THE AREA BY LATER AFTERNOON...WITH PERHAPS THE LEADING
HINT OF LOWER BASED DEVELOPMENT BY VERY LATE AFTERNOON OR EARLY
EVENING ALONG THE FAR SOUTHEAST CORNER OF THE CWA.

THE PERIOD FROM FRIDAY THROUGH SUNDAY WILL TRANSITION BACK TO
NORTHWESTERLY FLOW...WITH A LARGE COOL AREA OF HIGH PRESSURE
SETTLING THROUGH THE NORTHERN PLAINS. THIS WILL DRIVE BOUNDARY
SOUTHWARD...AND OTHER THAN A REMOTE CHANCE FOR A HIGH PLAINS
DEVELOPMENT TO BRUSH THE FAR SOUTHWEST CWA WITH AN ILL-TIMED
WEAK WAVE AROUND FRIDAY OR SATURDAY...WILL BE DRY AND QUITE
COOL...WITH HIGHS IN THE UPPER 60S TO LOWER 70S...AND LOWS IN
THE MID 40S TO LOWER 50S.

TRANSITION BACK TOWARD ZONAL TO WEAKLY SOUTHWEST FLOW TOWARD THE
END OF THE PERIOD...WITH LOW LEVEL SOUTHERLY FLOW INCREASING ALONG
WITH MOISTURE CONTENT OF AIR. WITH NORTHERN STREAM WAVE INDUCING
INCREASE LOWER TO MID LEVEL THETA E ADVECTION BY SUNDAY NIGHT AND
MONDAY...CONTINUED TO INDICATE A LOWER CHANCE FOR THUNDERSTORMS.
TEMPS START TO MODERATE WITH MORE CLOUDS AND INCREASED MOISTURE...
BUT STILL REMAIN BELOW NORMAL THROUGH MONDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 611 PM CDT MON SEP 1 2014

SCATTERED CONVECTION DEVELOPING OVER CENTRAL SOUTH DAKOTA WILL
MOVE EASTWARD OVERNIGHT...AFFECTING THE TAF SITES IN THE EVENING
HOURS. MAY SEE PATCHY FOG DEVELOPMENT LATER AT NIGHT AROUND KFSD
AND KSUX AFTER SHOWERS END WITH LIGHT WINDS SITUATED ACROSS THE
AREA.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...JM




000
FXUS63 KFSD 020903
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
403 AM CDT TUE SEP 2 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CDT TUE SEP 2 2014

WAVE WILL EXIT TO OUR EAST THIS MORNING...GIVING WAY TO A MOSTLY
SUNNY DAY ACROSS THE REGION. TEMPERATURES ALOFT CONTINUE TO
WARM...BUT AS FLOW TURNS MORE SOUTHERLY...DO NOT THINK MIXING WILL
BE AS GOOD. EITHER WAY...MOST GUIDANCE SEEMS TOO LOW GIVEN MODEL 850
AND 925 MB TEMPERATURES...THUS CONTINUED ON THE WARM SIDE OF
GUIDANCE. LOOKING FOR UPPER 70S TO LOW 80S ACROSS THE AREA...WHICH
IS AROUND OR JUST ABOVE AVERAGE FOR THIS TIME OF YEAR.

LOW LEVEL JET PICKS UP TONIGHT...INCREASING THETA E ADVECTION AND
ISENTROPIC LIFT OVER THE REGION. INSTABILITY WILL INCREASE AS A
RESULT...ALTHOUGH EXPECT THE LOWER LEVELS TO REMAIN CAPPED AS
WARMER TEMPERATURES ALOFT ADVECT IN AS WELL. THUS LOOKING LIKE ANY
CONVECTIVE ACTIVITY WILL PROBABLY END UP BASED AROUND 800 MB OR
SO. MODEL CONSENSUS SUGGESTS BEST CHANCE OF SEEING SOME ELEVATED
SHOWER OR THUNDERSTORM ACTIVITY WILL BE ALONG AND NORTHEAST OF A
HURON TO SIOUX FALLS TO STORM LAKE LINE. BASED ON LOW LEVEL JET
LOCATION AND ORIENTATION THIS MAKES SENSE AS WELL...SO FOCUSED
POPS IN THIS AREA. THINK ACTIVITY WILL PROBABLY JUST REMAIN
ISOLATED TO SCATTERED BETWEEN 3 AM AND 7 AM. NAM SEEMS OVERDONE
WITH INSTABILITY ORIGINATING FROM 800 MB...SUGGESTING OVER 2000
J/KG. GFS AND ECMWF SOLUTIONS SEEM MORE REASONABLE...WITH 1000
J/KG OR LESS OF ELEVATED CAPE. STORMS WILL BE BASED ABOVE THE BEST
SHEAR AS WELL...SO OTHER THAN MAYBE SOME SMALL HAIL...WOULD NOT
EXPECT ANYTHING TOO STRONG THROUGH 12Z. WITH SOUTHERLY FLOW
INCREASING OVERNIGHT...WARMED LOWS A FEW DEGREES INTO THE LOW TO
MID 60S.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 403 AM CDT TUE SEP 2 2014

LIKELY THAT ISOLATED TO SCATTERED NOCTURNAL ELEVATED CONVECTION
WILL BE ONGOING AT THE START OF WEDNESDAY OVER THE NORTHEAST HALF
OF THE CWA. NAM SOLUTION REJECTED FOR SEVERAL REASONS...NOT THE
LEAST BEING SOME VERY UNREALISTIC THERMODYNAMIC PROFILES...WHICH
ARE ALLOWING A MUCH FURTHER SOUTH DEVELOPMENT INTO THE APPROACHING
CAP. WILL WATCH MID LEVEL FOCUS FOR THIS CONVECTION PULL OFF TO
THE NORTHEAST DURING THE DAY. OTHER ISSUE WITH WEDNESDAY WILL BE
THREAT FOR STRATUS DEVELOPMENT EARLY MORNING TO PERSIST LONGER
INTO THE DAY IN THE EAST TO GREATLY IMPACT TEMPERATURES. EAST OF
I 29 LIKELY TO SEE VERY LIMITED SUNSHINE INTO EARLY AFTERNOON...
PERHAPS EVEN A BIT MORE PESSIMISTIC THAN GOING FORECAST. AREAS TO
THE WEST WILL BE POISED TO HOLD ON TO OR BREAK OUT INTO SUNSHINE
MUCH EARLIER...WITH TEMPS VARYING FROM LOWER 80S EAST TO LOWER 90S
WEST BY AFTERNOON. VERY STRONG CAP INDICATED BY WEDNESDAY
AFTERNOON...SO HARD TO PICTURE BEING ABLE TO CONTINUE ANY THREAT
OF CONVECTION PAST A SMALL CHANCE MIDDAY FOR EVACUATING HIGH BASED
STORMS ON NOSE OF THE 7-9C/KM MID LEVEL LAPSE RATES.

STRONG PACIFIC NW WAVE WILL START TO KNOCK DOWN THE FLAT RIDGING
ACROSS THE NORTHERN PLAINS BY LATER WEDNESDAY NIGHT...WITH
CYCLOGENESIS ACROSS THE NORTHERN PLAINS...DRAGGING A FAIRLY STRONG
COLD FRONT TOWARD THE I 29 CORRIDOR BY EARLY THURSDAY MORNING.
BOUNDARY STRONGLY CAPPED AND CONVERGENCE LACKING...WITH DEEPER
DYNAMICAL LIFT FORCING LAGGING BEHIND WITH MID/HIGH LEVEL
MOISTURE. PROSPECT FOR ANY MEANINGFUL PRECIPITATION CHANCES ON
LATER THURSDAY AND THURSDAY NIGHT ARE REALLY NOT THERE...WITH JUST
A MINIMAL THREAT FOR A HIGHER BASED SHOWER OR EVEN LESS LIKELY A
THUNDERSTORM ALONG WITH DIV Q AXIS SLIPPING SOUTHEASTWARD BEHIND
BOUNDARY. LOW LEVEL FRONTAL BOUNDARY IS VERY WELL REMOVED TO THE
SOUTH OF THE AREA BY LATER AFTERNOON...WITH PERHAPS THE LEADING
HINT OF LOWER BASED DEVELOPMENT BY VERY LATE AFTERNOON OR EARLY
EVENING ALONG THE FAR SOUTHEAST CORNER OF THE CWA.

THE PERIOD FROM FRIDAY THROUGH SUNDAY WILL TRANSITION BACK TO
NORTHWESTERLY FLOW...WITH A LARGE COOL AREA OF HIGH PRESSURE
SETTLING THROUGH THE NORTHERN PLAINS. THIS WILL DRIVE BOUNDARY
SOUTHWARD...AND OTHER THAN A REMOTE CHANCE FOR A HIGH PLAINS
DEVELOPMENT TO BRUSH THE FAR SOUTHWEST CWA WITH AN ILL-TIMED
WEAK WAVE AROUND FRIDAY OR SATURDAY...WILL BE DRY AND QUITE
COOL...WITH HIGHS IN THE UPPER 60S TO LOWER 70S...AND LOWS IN
THE MID 40S TO LOWER 50S.

TRANSITION BACK TOWARD ZONAL TO WEAKLY SOUTHWEST FLOW TOWARD THE
END OF THE PERIOD...WITH LOW LEVEL SOUTHERLY FLOW INCREASING ALONG
WITH MOISTURE CONTENT OF AIR. WITH NORTHERN STREAM WAVE INDUCING
INCREASE LOWER TO MID LEVEL THETA E ADVECTION BY SUNDAY NIGHT AND
MONDAY...CONTINUED TO INDICATE A LOWER CHANCE FOR THUNDERSTORMS.
TEMPS START TO MODERATE WITH MORE CLOUDS AND INCREASED MOISTURE...
BUT STILL REMAIN BELOW NORMAL THROUGH MONDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 611 PM CDT MON SEP 1 2014

SCATTERED CONVECTION DEVELOPING OVER CENTRAL SOUTH DAKOTA WILL
MOVE EASTWARD OVERNIGHT...AFFECTING THE TAF SITES IN THE EVENING
HOURS. MAY SEE PATCHY FOG DEVELOPMENT LATER AT NIGHT AROUND KFSD
AND KSUX AFTER SHOWERS END WITH LIGHT WINDS SITUATED ACROSS THE
AREA.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...JM





000
FXUS63 KFSD 012329
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
629 PM CDT MON SEP 1 2014

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 355 PM CDT MON SEP 1 2014

ISOLATED STORMS IN THE EASTERN CWA PRIMARILY DIURNALLY DRIVEN AND
SHOULD DIMINISH TOWARD SUNSET. FARTHER WEST...UPPER WAVE TRACKING
OUT OF THE WESTERN HIGH PLAINS WILL CONTINUE TO SPARK MAINLY MID
LEVEL BASED THUNDERSTORMS AS IT MOVES EAST ACROSS THE FORECAST AREA
OVERNIGHT. WHILE MOST STORMS SHOULD REMAIN BELOW SEVERE LIMITS...
WITH RELATIVELY DRY SUB-CLOUD LAYER...CANNOT RULE OUT ISOLATED
STRONGER WIND GUSTS INTO THE EARLY EVENING. WITH EXPECTED CLOUD
COVER AS THE WAVE MOVES THROUGH...BUMPED UP LOWS A BIT FROM PREVIOUS
FORECAST...WITH MID TO UPPER 50S EXPECTED IN MOST AREAS.

SHOWERS/THUNDERSTORMS SHOULD EXIT THE EASTERN CWA EARLY TUESDAY
MORNING...FOLLOWED BY MOSTLY SUNNY SKIES AND MILD TEMPERATURES
WARMING INTO THE UPPER 70S TO LOWER 80S.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 PM CDT MON SEP 1 2014

MID LEVEL WARM AIR ADVECTION DEVELOPS TUESDAY NIGHT...ALLOWING
CLOUDS TO INCREASE FROM THE SOUTH OVERNIGHT. COULD SEE ENOUGH WEAK
CONVERGENCE TO TRIGGER SOME ISOLATED SHOWERS AND PERHAPS A FEW
RUMBLES OF THUNDER ACROSS OUR WESTERN AND NORTHERN FORECAST
AREA...MAINLY LATE AT NIGHT INTO WEDNESDAY MORNING AS THE LOW LEVEL
JET NOSES INTO SOUTH CENTRAL SOUTH DAKOTA AND A WEAK MID LEVEL
IMPULSE LIFTS NORTHEAST INTO THE AREA. WITH SOME DECENT WARMING AND
BREEZY SOUTHERLY WINDS DOMINATING WEDNESDAY...TEMPERATURES WILL WARM
SIGNIFICANTLY IN OUR WEST...APPROACHING HIGHS NEAR 90. FURTHER
EAST...TEMPERATURES WILL ALSO IMPROVE IMPROVE INTO THE MID TO UPPER
80S...BUT COULD BE TEMPERED SOME BY RESIDUAL MID LEVEL CLOUDS INTO
THE AFTERNOON HOURS.

SURFACE LOW DEEPENS OVER THE CENTRAL DAKOTAS WEDNESDAY NIGHT AND
LIFTS INTO NORTHERN MINNESOTA THURSDAY AFTERNOON AS AN UPPER TROUGH
SKIMS THE NORTH DAKOTA AND CANADIAN BORDER. ISOLATED WARM AIR
ADVECTION SHOWERS AND THUNDERSTORMS WILL AGAIN BE POSSIBLE ACROSS
OUR NORTHEASTERN HALF...MAINLY IN THE LATE AFTERNOON AND EVENING ON
WEDNESDAY. A COLD FRONT TRACKS EAST ACROSS THE FORECAST AREA DURING
THE DAY ON THURSDAY...BRINGING ANOTHER CHANCE OF SHOWERS AND
THUNDERSTORMS ALONG WITH THE FRONT...MAINLY IN THE EVENING ACROSS
NORTHWEST IOWA AND ADJACENT COUNTIES. STILL QUITE A BIT OF
UNCERTAINTY IN THE TIMING AND LOCATION OF THIS FRONT...WITH THE GEM
DROPPING THE FRONT MUCH FURTHER SOUTH THAN THE OTHER
MODELS...AND WELL AWAY FROM THE FORECAST AREA ON THURSDAY.

SURFACE RIDGE EXPANDS INTO THE REGION FRIDAY THROUGH
SUNDAY...LEADING TO SOME PLEASANT...COOL AND DRY WEATHER CONDITIONS.
HIGHS WILL DROP WELL BELOW NORMAL...ONLY TOPPING OUT IN THE UPPER
60S AND LOWER 70S ON FRIDAY AND SATURDAY...AND IMPROVING A FEW
DEGREES ON SUNDAY. MODELS DIVERGE SIGNFICANTLY EARLY NEXT
WEEK...WITH THE GFS DEVELOPING SOME STRONG WARM AIR ADVECTION INTO
WESTERN AND CENTRAL SOUTH DAKOTA AND SOME SCATTERED SHOWERS AND
THUNDERSTORMS AS EARLY AS SUNDAY NIGHT. CONFIDENCE REMAINS LOW
HOWEVER...GIVEN THE MUCH DRIER PATTERN SEEN IN THE ECMWF.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 611 PM CDT MON SEP 1 2014

SCATTERED CONVECTION DEVELOPING OVER CENTRAL SOUTH DAKOTA WILL
MOVE EASTWARD OVERNIGHT...AFFECTING THE TAF SITES IN THE EVENING
HOURS. MAY SEE PATCHY FOG DEVELOPMENT LATER AT NIGHT AROUND KFSD
AND KSUX AFTER SHOWERS END WITH LIGHT WINDS SITUATED ACROSS THE
AREA.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...
LONG TERM...
AVIATION...JM





000
FXUS63 KFSD 012329
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
629 PM CDT MON SEP 1 2014

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 355 PM CDT MON SEP 1 2014

ISOLATED STORMS IN THE EASTERN CWA PRIMARILY DIURNALLY DRIVEN AND
SHOULD DIMINISH TOWARD SUNSET. FARTHER WEST...UPPER WAVE TRACKING
OUT OF THE WESTERN HIGH PLAINS WILL CONTINUE TO SPARK MAINLY MID
LEVEL BASED THUNDERSTORMS AS IT MOVES EAST ACROSS THE FORECAST AREA
OVERNIGHT. WHILE MOST STORMS SHOULD REMAIN BELOW SEVERE LIMITS...
WITH RELATIVELY DRY SUB-CLOUD LAYER...CANNOT RULE OUT ISOLATED
STRONGER WIND GUSTS INTO THE EARLY EVENING. WITH EXPECTED CLOUD
COVER AS THE WAVE MOVES THROUGH...BUMPED UP LOWS A BIT FROM PREVIOUS
FORECAST...WITH MID TO UPPER 50S EXPECTED IN MOST AREAS.

SHOWERS/THUNDERSTORMS SHOULD EXIT THE EASTERN CWA EARLY TUESDAY
MORNING...FOLLOWED BY MOSTLY SUNNY SKIES AND MILD TEMPERATURES
WARMING INTO THE UPPER 70S TO LOWER 80S.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 PM CDT MON SEP 1 2014

MID LEVEL WARM AIR ADVECTION DEVELOPS TUESDAY NIGHT...ALLOWING
CLOUDS TO INCREASE FROM THE SOUTH OVERNIGHT. COULD SEE ENOUGH WEAK
CONVERGENCE TO TRIGGER SOME ISOLATED SHOWERS AND PERHAPS A FEW
RUMBLES OF THUNDER ACROSS OUR WESTERN AND NORTHERN FORECAST
AREA...MAINLY LATE AT NIGHT INTO WEDNESDAY MORNING AS THE LOW LEVEL
JET NOSES INTO SOUTH CENTRAL SOUTH DAKOTA AND A WEAK MID LEVEL
IMPULSE LIFTS NORTHEAST INTO THE AREA. WITH SOME DECENT WARMING AND
BREEZY SOUTHERLY WINDS DOMINATING WEDNESDAY...TEMPERATURES WILL WARM
SIGNIFICANTLY IN OUR WEST...APPROACHING HIGHS NEAR 90. FURTHER
EAST...TEMPERATURES WILL ALSO IMPROVE IMPROVE INTO THE MID TO UPPER
80S...BUT COULD BE TEMPERED SOME BY RESIDUAL MID LEVEL CLOUDS INTO
THE AFTERNOON HOURS.

SURFACE LOW DEEPENS OVER THE CENTRAL DAKOTAS WEDNESDAY NIGHT AND
LIFTS INTO NORTHERN MINNESOTA THURSDAY AFTERNOON AS AN UPPER TROUGH
SKIMS THE NORTH DAKOTA AND CANADIAN BORDER. ISOLATED WARM AIR
ADVECTION SHOWERS AND THUNDERSTORMS WILL AGAIN BE POSSIBLE ACROSS
OUR NORTHEASTERN HALF...MAINLY IN THE LATE AFTERNOON AND EVENING ON
WEDNESDAY. A COLD FRONT TRACKS EAST ACROSS THE FORECAST AREA DURING
THE DAY ON THURSDAY...BRINGING ANOTHER CHANCE OF SHOWERS AND
THUNDERSTORMS ALONG WITH THE FRONT...MAINLY IN THE EVENING ACROSS
NORTHWEST IOWA AND ADJACENT COUNTIES. STILL QUITE A BIT OF
UNCERTAINTY IN THE TIMING AND LOCATION OF THIS FRONT...WITH THE GEM
DROPPING THE FRONT MUCH FURTHER SOUTH THAN THE OTHER
MODELS...AND WELL AWAY FROM THE FORECAST AREA ON THURSDAY.

SURFACE RIDGE EXPANDS INTO THE REGION FRIDAY THROUGH
SUNDAY...LEADING TO SOME PLEASANT...COOL AND DRY WEATHER CONDITIONS.
HIGHS WILL DROP WELL BELOW NORMAL...ONLY TOPPING OUT IN THE UPPER
60S AND LOWER 70S ON FRIDAY AND SATURDAY...AND IMPROVING A FEW
DEGREES ON SUNDAY. MODELS DIVERGE SIGNFICANTLY EARLY NEXT
WEEK...WITH THE GFS DEVELOPING SOME STRONG WARM AIR ADVECTION INTO
WESTERN AND CENTRAL SOUTH DAKOTA AND SOME SCATTERED SHOWERS AND
THUNDERSTORMS AS EARLY AS SUNDAY NIGHT. CONFIDENCE REMAINS LOW
HOWEVER...GIVEN THE MUCH DRIER PATTERN SEEN IN THE ECMWF.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 611 PM CDT MON SEP 1 2014

SCATTERED CONVECTION DEVELOPING OVER CENTRAL SOUTH DAKOTA WILL
MOVE EASTWARD OVERNIGHT...AFFECTING THE TAF SITES IN THE EVENING
HOURS. MAY SEE PATCHY FOG DEVELOPMENT LATER AT NIGHT AROUND KFSD
AND KSUX AFTER SHOWERS END WITH LIGHT WINDS SITUATED ACROSS THE
AREA.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...
LONG TERM...
AVIATION...JM




000
FXUS63 KFSD 012056
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
356 PM CDT MON SEP 1 2014

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 355 PM CDT MON SEP 1 2014

AS OF 20Z...COLD FRONT HAD WORKED ITS WAY EAST TO JUST WEST OF
MARSHALL MN TO SIOUX FALLS SD TO JUST WEST OF SIOUX CITY. EXPECT
DEEP CONVECTION TO BE FOCUSED ALONG AND EAST OF THE BOUNDARY. HAVE
ADJUSTED THE HWO TO FOCUS ON THE HIGHWAY 60 AND EAST
CORRIDOR...WHERE STORMS ARE EXPECTED TO DEVELOP AROUND 22Z WITH THE
POTENTIAL FOR LARGE HAIL...DAMAGING WINDS AND ISOLATE TORNADOES.
WITH NEAR SURFACE LAYER FLOW BECOMING SOUTHWEST...STILL NOT A TON OF
DIRECTIONAL SHEAR...BUT STILL SOME DECENT SPEED SHEAR TO AID IN
STORM ORGANIZATION.  BETTER BACKED FLOW FURTHER TO THE SOUTH ALONG
THE I-80 CORRIDOR IN WESTERN AND CENTRAL IOWA AIDING IN BETTER
FELICITY. DO NOT EXPECT THIS BOUNDARY TO WORK MUCH FURTHER NORTH
THAN HIGHWAY 30 SOUTH OF OUR FORECAST AREA...THEREFORE...MAIN SEVERE
WEATHER THREATS SHOULD BE PRIMARILY WIND AND HAIL DRIVEN FOR THE
EASTERN PORTIONS OF OUR FORECAST AREA.  WITH AFOREMENTIONED SPEED
SHEAR AND CAPE VALUES AROUND 1500-2000 J/KG AND MINIMAL CAP...EXPECT
STORMS TO DEVELOP AS SHORTWAVE LIFTING FROM SOUTHEAST AIDS IN UPPER
LEVEL SUPPORT AND LIFT.

EXPECT SEVERE THREAT TO SHIFT EAST OF THE AREA AFTER 03Z.  STILL MAY
HAVE SOME POST FRONTAL SHOWERS SHIFT THROUGH THE AREA OVERNIGHT.

COOLER AND DRIER CONDITIONS ARE EXPECTED ON MONDAY...WITH NEAR
NORMAL HIGHS IN THE MID AND UPPER 70S.  FAST MOVING SHORT WAVE
APPROACHING FROM THE WEST MAY GENERATE A FEW LATE AFTERNOON
THUNDERSTORMS ACROSS CENTRAL SOUTH DAKOTA...BUT SHOULD REMAIN BELOW
SEVERE LIMITS WITH LIMITED AMOUNTS OF MOISTURE AND INSTABILITY.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 PM CDT MON SEP 1 2014

MID LEVEL WARM AIR ADVECTION DEVELOPS TUESDAY NIGHT...ALLOWING
CLOUDS TO INCREASE FROM THE SOUTH OVERNIGHT. COULD SEE ENOUGH WEAK
CONVERGENCE TO TRIGGER SOME ISOLATED SHOWERS AND PERHAPS A FEW
RUMBLES OF THUNDER ACROSS OUR WESTERN AND NORTHERN FORECAST
AREA...MAINLY LATE AT NIGHT INTO WEDNESDAY MORNING AS THE LOW LEVEL
JET NOSES INTO SOUTH CENTRAL SOUTH DAKOTA AND A WEAK MID LEVEL
IMPULSE LIFTS NORTHEAST INTO THE AREA. WITH SOME DECENT WARMING AND
BREEZY SOUTHERLY WINDS DOMINATING WEDNESDAY...TEMPERATURES WILL WARM
SIGNIFICANTLY IN OUR WEST...APPROACHING HIGHS NEAR 90. FURTHER
EAST...TEMPERATURES WILL ALSO IMPROVE IMPROVE INTO THE MID TO UPPER
80S...BUT COULD BE TEMPERED SOME BY RESIDUAL MID LEVEL CLOUDS INTO
THE AFTERNOON HOURS.

SURFACE LOW DEEPENS OVER THE CENTRAL DAKOTAS WEDNESDAY NIGHT AND
LIFTS INTO NORTHERN MINNESOTA THURSDAY AFTERNOON AS AN UPPER TROUGH
SKIMS THE NORTH DAKOTA AND CANADIAN BORDER. ISOLATED WARM AIR
ADVECTION SHOWERS AND THUNDERSTORMS WILL AGAIN BE POSSIBLE ACROSS
OUR NORTHEASTERN HALF...MAINLY IN THE LATE AFTERNOON AND EVENING ON
WEDNESDAY. A COLD FRONT TRACKS EAST ACROSS THE FORECAST AREA DURING
THE DAY ON THURSDAY...BRINGING ANOTHER CHANCE OF SHOWERS AND
THUNDERSTORMS ALONG WITH THE FRONT...MAINLY IN THE EVENING ACROSS
NORTHWEST IOWA AND ADJACENT COUNTIES. STILL QUITE A BIT OF
UNCERTAINTY IN THE TIMING AND LOCATION OF THIS FRONT...WITH THE GEM
DROPPING THE FRONT MUCH FURTHER SOUTH THAN THE OTHER
MODELS...AND WELL AWAY FROM THE FORECAST AREA ON THURSDAY.

SURFACE RIDGE EXPANDS INTO THE REGION FRIDAY THROUGH
SUNDAY...LEADING TO SOME PLEASANT...COOL AND DRY WEATHER CONDITIONS.
HIGHS WILL DROP WELL BELOW NORMAL...ONLY TOPPING OUT IN THE UPPER
60S AND LOWER 70S ON FRIDAY AND SATURDAY...AND IMPROVING A FEW
DEGREES ON SUNDAY. MODELS DIVERGE SIGNFICANTLY EARLY NEXT
WEEK...WITH THE GFS DEVELOPING SOME STRONG WARM AIR ADVECTION INTO
WESTERN AND CENTRAL SOUTH DAKOTA AND SOME SCATTERED SHOWERS AND
THUNDERSTORMS AS EARLY AS SUNDAY NIGHT. CONFIDENCE REMAINS LOW
HOWEVER...GIVEN THE MUCH DRIER PATTERN SEEN IN THE ECMWF.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1232 PM CDT MON SEP 1 2014

FOCUS THIS SET OF TAFS WAS THE CONVECTION THAT IS EXPECTED TO
DEVELOP ACROSS WEST CENTRAL SOUTH DAKOTA THIS AFTERNOON...AND
SPREAD EAST OVERNIGHT. HAVE ADDED HIGH BASED SHOWERS TO THE
FORECAST..THOUGH LIMITED INSTABILITY MAY LEAD TO A RUMBLE OF
THUNDER OR TWO AT TAF SITES. WESTERLY FLOW PREVAILS THROUGH THE
PERIOD...GENERALLY REMAINLY AT OR BELOW 10 KNOTS.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...
LONG TERM...
AVIATION...





000
FXUS63 KFSD 012056
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
356 PM CDT MON SEP 1 2014

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 355 PM CDT MON SEP 1 2014

AS OF 20Z...COLD FRONT HAD WORKED ITS WAY EAST TO JUST WEST OF
MARSHALL MN TO SIOUX FALLS SD TO JUST WEST OF SIOUX CITY. EXPECT
DEEP CONVECTION TO BE FOCUSED ALONG AND EAST OF THE BOUNDARY. HAVE
ADJUSTED THE HWO TO FOCUS ON THE HIGHWAY 60 AND EAST
CORRIDOR...WHERE STORMS ARE EXPECTED TO DEVELOP AROUND 22Z WITH THE
POTENTIAL FOR LARGE HAIL...DAMAGING WINDS AND ISOLATE TORNADOES.
WITH NEAR SURFACE LAYER FLOW BECOMING SOUTHWEST...STILL NOT A TON OF
DIRECTIONAL SHEAR...BUT STILL SOME DECENT SPEED SHEAR TO AID IN
STORM ORGANIZATION.  BETTER BACKED FLOW FURTHER TO THE SOUTH ALONG
THE I-80 CORRIDOR IN WESTERN AND CENTRAL IOWA AIDING IN BETTER
FELICITY. DO NOT EXPECT THIS BOUNDARY TO WORK MUCH FURTHER NORTH
THAN HIGHWAY 30 SOUTH OF OUR FORECAST AREA...THEREFORE...MAIN SEVERE
WEATHER THREATS SHOULD BE PRIMARILY WIND AND HAIL DRIVEN FOR THE
EASTERN PORTIONS OF OUR FORECAST AREA.  WITH AFOREMENTIONED SPEED
SHEAR AND CAPE VALUES AROUND 1500-2000 J/KG AND MINIMAL CAP...EXPECT
STORMS TO DEVELOP AS SHORTWAVE LIFTING FROM SOUTHEAST AIDS IN UPPER
LEVEL SUPPORT AND LIFT.

EXPECT SEVERE THREAT TO SHIFT EAST OF THE AREA AFTER 03Z.  STILL MAY
HAVE SOME POST FRONTAL SHOWERS SHIFT THROUGH THE AREA OVERNIGHT.

COOLER AND DRIER CONDITIONS ARE EXPECTED ON MONDAY...WITH NEAR
NORMAL HIGHS IN THE MID AND UPPER 70S.  FAST MOVING SHORT WAVE
APPROACHING FROM THE WEST MAY GENERATE A FEW LATE AFTERNOON
THUNDERSTORMS ACROSS CENTRAL SOUTH DAKOTA...BUT SHOULD REMAIN BELOW
SEVERE LIMITS WITH LIMITED AMOUNTS OF MOISTURE AND INSTABILITY.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 PM CDT MON SEP 1 2014

MID LEVEL WARM AIR ADVECTION DEVELOPS TUESDAY NIGHT...ALLOWING
CLOUDS TO INCREASE FROM THE SOUTH OVERNIGHT. COULD SEE ENOUGH WEAK
CONVERGENCE TO TRIGGER SOME ISOLATED SHOWERS AND PERHAPS A FEW
RUMBLES OF THUNDER ACROSS OUR WESTERN AND NORTHERN FORECAST
AREA...MAINLY LATE AT NIGHT INTO WEDNESDAY MORNING AS THE LOW LEVEL
JET NOSES INTO SOUTH CENTRAL SOUTH DAKOTA AND A WEAK MID LEVEL
IMPULSE LIFTS NORTHEAST INTO THE AREA. WITH SOME DECENT WARMING AND
BREEZY SOUTHERLY WINDS DOMINATING WEDNESDAY...TEMPERATURES WILL WARM
SIGNIFICANTLY IN OUR WEST...APPROACHING HIGHS NEAR 90. FURTHER
EAST...TEMPERATURES WILL ALSO IMPROVE IMPROVE INTO THE MID TO UPPER
80S...BUT COULD BE TEMPERED SOME BY RESIDUAL MID LEVEL CLOUDS INTO
THE AFTERNOON HOURS.

SURFACE LOW DEEPENS OVER THE CENTRAL DAKOTAS WEDNESDAY NIGHT AND
LIFTS INTO NORTHERN MINNESOTA THURSDAY AFTERNOON AS AN UPPER TROUGH
SKIMS THE NORTH DAKOTA AND CANADIAN BORDER. ISOLATED WARM AIR
ADVECTION SHOWERS AND THUNDERSTORMS WILL AGAIN BE POSSIBLE ACROSS
OUR NORTHEASTERN HALF...MAINLY IN THE LATE AFTERNOON AND EVENING ON
WEDNESDAY. A COLD FRONT TRACKS EAST ACROSS THE FORECAST AREA DURING
THE DAY ON THURSDAY...BRINGING ANOTHER CHANCE OF SHOWERS AND
THUNDERSTORMS ALONG WITH THE FRONT...MAINLY IN THE EVENING ACROSS
NORTHWEST IOWA AND ADJACENT COUNTIES. STILL QUITE A BIT OF
UNCERTAINTY IN THE TIMING AND LOCATION OF THIS FRONT...WITH THE GEM
DROPPING THE FRONT MUCH FURTHER SOUTH THAN THE OTHER
MODELS...AND WELL AWAY FROM THE FORECAST AREA ON THURSDAY.

SURFACE RIDGE EXPANDS INTO THE REGION FRIDAY THROUGH
SUNDAY...LEADING TO SOME PLEASANT...COOL AND DRY WEATHER CONDITIONS.
HIGHS WILL DROP WELL BELOW NORMAL...ONLY TOPPING OUT IN THE UPPER
60S AND LOWER 70S ON FRIDAY AND SATURDAY...AND IMPROVING A FEW
DEGREES ON SUNDAY. MODELS DIVERGE SIGNFICANTLY EARLY NEXT
WEEK...WITH THE GFS DEVELOPING SOME STRONG WARM AIR ADVECTION INTO
WESTERN AND CENTRAL SOUTH DAKOTA AND SOME SCATTERED SHOWERS AND
THUNDERSTORMS AS EARLY AS SUNDAY NIGHT. CONFIDENCE REMAINS LOW
HOWEVER...GIVEN THE MUCH DRIER PATTERN SEEN IN THE ECMWF.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1232 PM CDT MON SEP 1 2014

FOCUS THIS SET OF TAFS WAS THE CONVECTION THAT IS EXPECTED TO
DEVELOP ACROSS WEST CENTRAL SOUTH DAKOTA THIS AFTERNOON...AND
SPREAD EAST OVERNIGHT. HAVE ADDED HIGH BASED SHOWERS TO THE
FORECAST..THOUGH LIMITED INSTABILITY MAY LEAD TO A RUMBLE OF
THUNDER OR TWO AT TAF SITES. WESTERLY FLOW PREVAILS THROUGH THE
PERIOD...GENERALLY REMAINLY AT OR BELOW 10 KNOTS.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...
LONG TERM...
AVIATION...




000
FXUS63 KFSD 011735
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1235 PM CDT MON SEP 1 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM CDT MON SEP 1 2014

UPPER LOW OVER THE CWA EARLY THIS MORNING GENERATING ISOLATED TO
SCATTERED SHOWERS. THESE ARE IN A WEAKENING STATE...AND THINKING
SHOULD GENERALLY BE DRY BY 12Z. WILL LIKELY SEE SOME CU AND
EVENTUALLY SOME CIRRUS MOVING IN FROM THE WEST TODAY...BUT SHOULD
GENERALLY BE A PARTLY TO MOSTLY SUNNY DAY. BASED ON THERMAL FIELDS
AND EXPECTED SUNSHINE...DID BUMP UP HIGHS A BIT...LOOKING FOR MID TO
UPPER 70S OVER THE AREA. A WAVE CURRENTLY ENTERING WYOMING WILL
QUICKLY PUSH EAST TODAY...MOVING OVER OUR AREA LATER THIS AFTERNOON
AND EVENING. PRETTY GOOD UPPER LEVEL FORCING WITH THIS WAVE...BUT WE
LACK A LOW LEVEL FORCING MECHANISM. CAP IS RELATIVELY SMALL...BUT
WITHOUT THIS FORCING MECHANISM...THINK IT WILL PROBABLY HOLD OVER
MOST OF THE AREA THIS AFTERNOON...KEEPING IT MAINLY DRY.

THERE DOES APPEAR TO BE AN AREA OF LOCALLY ENHANCED CONVERGENCE
ACROSS WESTERN MINNESOTA...AND HI RES MODELS ARE ALL SHOWING
DEVELOPMENT IN THIS AREA. THINK MOST OF THE SHOWERS AND STORMS IN
THIS AREA WILL PROBABLY STAY NORTHEAST OF OUR CWA...BUT INCLUDED
SOME LOW POPS NEAR MARSHALL. OTHER AREA WHERE STORMS MAY DEVELOP
THIS AFTERNOON IS ACROSS THE WESTERN PLAINS. THESE WILL TRACK
EAST...POSSIBLY APPROACHING CHAMBERLAIN AND GREGORY BY AROUND 0Z.
THUS ALSO WILL CARRY SOME POPS IN THIS AREA. GIVEN MINIMAL
CAPE...NOT MUCH OF A SEVERE THREAT...ALTHOUGH COULD BE SOME STRONG
WINDS WITH THE ACTIVITY ACROSS THE WESTERN PLAINS...POSSIBLY GETTING
INTO OUR SOUTH CENTRAL SOUTH DAKOTA COUNTIES. THINK MOST OF THE
ACTIVITY WILL DISSIPATE AFTER SUNSET...AND THUS WILL KEEP THE
FORECAST DRY IN BETWEEN THE TWO AREAS MENTIONED ABOVE. ALTHOUGH IF
WE HEAT ENOUGH...NOT OUT OF THE QUESTION WE COULD SEE AN ISOLATED
THUNDERSTORM JUST ABOUT ANYWHERE. SKIES CLEAR TONIGHT...BUT WE MAY
HOLD ON TO JUST ENOUGH OF A BREEZE TO PREVENT TEMPS FROM FALLING TOO
LOW...THOUGH STILL EXPECTING MID 50S.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 428 AM CDT MON SEP 1 2014

TUESDAY WILL OVERALL BE A PLEASANT DAY ACROSS THE AREA...AS
SURFACE RIDGE SLIPS SOUTHEAST...WITH ZONAL FLOW WORKING TOWARD
WEAK RIDGING. POTENTIAL FOR MID LEVEL BOUNDARY TO GET CAUGHT UP
JUST TO THE SOUTH OF THE AREA DURING THE DAY...SO COULD GET A FEW
HARMLESS MID CLOUDS ACROSS THE SOUTH...AND A SPILLOVER OF A FEW
HIGHER CLOUDS INTO THE NORTHERN AREAS. HIGHS WILL BE SEASONABLE IN
THE UPPER 70S AND LOWER 80S.

ON TUESDAY NIGHT...INCREASE IN MID LEVEL WARM AIR ADVECTION AND
PUSH OF THE ELEVATED MIXED LAYER INTO THE SOUTHWESTERN CWA. JUST
ENOUGH CONVERGENCE AND WEAK QG FORCING TO BE CONCERNED TOWARD THE
LATTER HALF OF THE NIGHT...AS BOUNDARY PUSHES SLOWLY NORTHEAST.ADDED
IN AN ISOLATED LEVEL POP FOR ELEVATED SHOWERS NORTH OF A HURON TO
SIOUX FALLS TO SPENCER LINE...BUT LOOKS LIKE ANY THUNDER IN A 50
J/KG MAX CAPE ENVIRONMENT WOULD BE EVEN MORE ROGUE THAN THE SHOWERS.
KEPT A SMALL LINGERING CHANCE DURING THE MORNING ACROSS SOUTHWEST
MINNESOTA AND EAST CENTRAL SD...BUT BOUNDARY SHOULD NOT WAIT
AROUND FOR LONG AS WEAK WAVE MOVES PAST.

WILL LIKELY HAVE SOME STRATUS BUILDING NORTHWARD ON TUESDAY NIGHT
ACROSS NEBRASKA...WITH A LATE NIGHT PULSE IN COVERAGE AS HIGHER
DEWPOINTS SNEAK IN BELOW WARMING TEMPS ALOFT. THIS STRATUS IS
ALMOST UNANIMOUSLY UNDERDONE IN MODEL SOLUTIONS...AND HAVE SOME
CONCERN THAT IT WILL NOT GO AWAY QUITE AS QUIETLY AS NAM/GFS/
CANADIAN/ECMWF SUGGEST. POTENTIAL IS THERE TO MESS UP WHAT WILL
LIKELY BE THE FINAL OF THE WARMER DAYS FOR A WHILE...AT LEAST
ACROSS SW MN AND NW IA...WHILE LOOKS A BIT MORE CERTAIN WITH
VEERING LOW LEVEL FLOW THAT THE WEST WILL BREAK OUT MORE READILY.
FOR NOW...HAVE SOME READINGS APPROACHING 90 IN THE WEST...AND HAVE
LOWER TO MID 80S IN THE EAST. WITH THE WARMER AND MUCH MORE HUMID
AIR MASS...THERMODYNAMICS PROFILES ARE CONCERNING GIVEN THE
3000-3500 J/KG MEAN CAPE BETWEEN OPERATIONAL MODELS...UNTIL
CONSIDERING THAT MID LEVEL BOUNDARY PUSHED NORTHEAST DURING THE
MORNING...AND THERE IS A GOOD SOLID 75-150 J/KG CAP ON THINGS...
ALONG WITH NEXT TO NO LARGER SCALE LIFT FORCING.

IN FACT...SHOULD BE CAPPED ENOUGH THAT AS STRONG WAVE CRASHES
INTO THE FLAT RIDGE ON WEDNESDAY NIGHT...INITIATING CYCLOGENESIS
TO THE WEST AND NORTH AND FORCES A STRONG COLD FRONT THROUGH THE
DAKOTAS...THIS FRONT SHOULD REMAIN LARGELY INERT OVERNIGHT AND
EVEN WELL INTO THURSDAY AS IT PUSHES INTO NORTHWEST IOWA BY
AFTERNOON. NAM REMAINS CONSISTENT WITH TRACK RECORD AS SLOWEST...
GFS FASTEST...AND OTHERS VARYING PACE BETWEEN. ONLY BY THURSDAY
AFTERNOON IN THE SOUTHEAST CWA AS MORE ORGANIZED AREA OF POST
FRONTAL Q VECTOR SUPPORT SWINGS OUT ACROSS THE BOUNDARY. SHOULD
GET A GOOD INCREASE IN PRECIPITATION ALONG AND POST FRONTAL DURING
THE EVENING...WHICH WILL THEN BUILD SOUTH AS STRONG LOW LEVEL
NORTHERLY DRYING WITH AGEOSTROPHIC SUPPORT OF JET ENTRANCE.

FOR THE MOST PART...HAVE LEFT THE REMAINING THREE DAYS OF THE
EXTENDED DRY AS SURFACE RIDGE TO THE NORTH WEDGES A GOOD DOSE OF
LOW LEVEL DRY AIR INTO THE REGION. SEVERAL SOLUTIONS ATTEMPT TO
BRING ANOTHER POST FRONTAL WAVE WITH A LITTLE MID LEVEL MOISTURE
POOLING AROUND THE START OF THE WEEKEND...BUT WITH MODELS
UNCERTAIN ON TIMING ON TOP OF THIS LOW LEVEL DRY AIR...DID NOT
MAKE SENSE TO ADD IN ANY LOWER CHANCE POPS AT THIS TIME. PERIOD OF
FRIDAY THROUGH SUNDAY WILL REMAIN COOL...WITH HIGHS IN THE UPPER
60S TO MID 70S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1232 PM CDT MON SEP 1 2014

FOCUS THIS SET OF TAFS WAS THE CONVECTION THAT IS EXPECTED TO
DEVELOP ACROSS WEST CENTRAL SOUTH DAKOTA THIS AFTERNOON...AND
SPREAD EAST OVERNIGHT. HAVE ADDED HIGH BASED SHOWERS TO THE
FORECAST..THOUGH LIMITED INSTABILITY MAY LEAD TO A RUMBLE OF
THUNDER OR TWO AT TAF SITES. WESTERLY FLOW PREVAILS THROUGH THE
PERIOD...GENERALLY REMAINLY AT OR BELOW 10 KNOTS.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...




000
FXUS63 KFSD 011735
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1235 PM CDT MON SEP 1 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM CDT MON SEP 1 2014

UPPER LOW OVER THE CWA EARLY THIS MORNING GENERATING ISOLATED TO
SCATTERED SHOWERS. THESE ARE IN A WEAKENING STATE...AND THINKING
SHOULD GENERALLY BE DRY BY 12Z. WILL LIKELY SEE SOME CU AND
EVENTUALLY SOME CIRRUS MOVING IN FROM THE WEST TODAY...BUT SHOULD
GENERALLY BE A PARTLY TO MOSTLY SUNNY DAY. BASED ON THERMAL FIELDS
AND EXPECTED SUNSHINE...DID BUMP UP HIGHS A BIT...LOOKING FOR MID TO
UPPER 70S OVER THE AREA. A WAVE CURRENTLY ENTERING WYOMING WILL
QUICKLY PUSH EAST TODAY...MOVING OVER OUR AREA LATER THIS AFTERNOON
AND EVENING. PRETTY GOOD UPPER LEVEL FORCING WITH THIS WAVE...BUT WE
LACK A LOW LEVEL FORCING MECHANISM. CAP IS RELATIVELY SMALL...BUT
WITHOUT THIS FORCING MECHANISM...THINK IT WILL PROBABLY HOLD OVER
MOST OF THE AREA THIS AFTERNOON...KEEPING IT MAINLY DRY.

THERE DOES APPEAR TO BE AN AREA OF LOCALLY ENHANCED CONVERGENCE
ACROSS WESTERN MINNESOTA...AND HI RES MODELS ARE ALL SHOWING
DEVELOPMENT IN THIS AREA. THINK MOST OF THE SHOWERS AND STORMS IN
THIS AREA WILL PROBABLY STAY NORTHEAST OF OUR CWA...BUT INCLUDED
SOME LOW POPS NEAR MARSHALL. OTHER AREA WHERE STORMS MAY DEVELOP
THIS AFTERNOON IS ACROSS THE WESTERN PLAINS. THESE WILL TRACK
EAST...POSSIBLY APPROACHING CHAMBERLAIN AND GREGORY BY AROUND 0Z.
THUS ALSO WILL CARRY SOME POPS IN THIS AREA. GIVEN MINIMAL
CAPE...NOT MUCH OF A SEVERE THREAT...ALTHOUGH COULD BE SOME STRONG
WINDS WITH THE ACTIVITY ACROSS THE WESTERN PLAINS...POSSIBLY GETTING
INTO OUR SOUTH CENTRAL SOUTH DAKOTA COUNTIES. THINK MOST OF THE
ACTIVITY WILL DISSIPATE AFTER SUNSET...AND THUS WILL KEEP THE
FORECAST DRY IN BETWEEN THE TWO AREAS MENTIONED ABOVE. ALTHOUGH IF
WE HEAT ENOUGH...NOT OUT OF THE QUESTION WE COULD SEE AN ISOLATED
THUNDERSTORM JUST ABOUT ANYWHERE. SKIES CLEAR TONIGHT...BUT WE MAY
HOLD ON TO JUST ENOUGH OF A BREEZE TO PREVENT TEMPS FROM FALLING TOO
LOW...THOUGH STILL EXPECTING MID 50S.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 428 AM CDT MON SEP 1 2014

TUESDAY WILL OVERALL BE A PLEASANT DAY ACROSS THE AREA...AS
SURFACE RIDGE SLIPS SOUTHEAST...WITH ZONAL FLOW WORKING TOWARD
WEAK RIDGING. POTENTIAL FOR MID LEVEL BOUNDARY TO GET CAUGHT UP
JUST TO THE SOUTH OF THE AREA DURING THE DAY...SO COULD GET A FEW
HARMLESS MID CLOUDS ACROSS THE SOUTH...AND A SPILLOVER OF A FEW
HIGHER CLOUDS INTO THE NORTHERN AREAS. HIGHS WILL BE SEASONABLE IN
THE UPPER 70S AND LOWER 80S.

ON TUESDAY NIGHT...INCREASE IN MID LEVEL WARM AIR ADVECTION AND
PUSH OF THE ELEVATED MIXED LAYER INTO THE SOUTHWESTERN CWA. JUST
ENOUGH CONVERGENCE AND WEAK QG FORCING TO BE CONCERNED TOWARD THE
LATTER HALF OF THE NIGHT...AS BOUNDARY PUSHES SLOWLY NORTHEAST.ADDED
IN AN ISOLATED LEVEL POP FOR ELEVATED SHOWERS NORTH OF A HURON TO
SIOUX FALLS TO SPENCER LINE...BUT LOOKS LIKE ANY THUNDER IN A 50
J/KG MAX CAPE ENVIRONMENT WOULD BE EVEN MORE ROGUE THAN THE SHOWERS.
KEPT A SMALL LINGERING CHANCE DURING THE MORNING ACROSS SOUTHWEST
MINNESOTA AND EAST CENTRAL SD...BUT BOUNDARY SHOULD NOT WAIT
AROUND FOR LONG AS WEAK WAVE MOVES PAST.

WILL LIKELY HAVE SOME STRATUS BUILDING NORTHWARD ON TUESDAY NIGHT
ACROSS NEBRASKA...WITH A LATE NIGHT PULSE IN COVERAGE AS HIGHER
DEWPOINTS SNEAK IN BELOW WARMING TEMPS ALOFT. THIS STRATUS IS
ALMOST UNANIMOUSLY UNDERDONE IN MODEL SOLUTIONS...AND HAVE SOME
CONCERN THAT IT WILL NOT GO AWAY QUITE AS QUIETLY AS NAM/GFS/
CANADIAN/ECMWF SUGGEST. POTENTIAL IS THERE TO MESS UP WHAT WILL
LIKELY BE THE FINAL OF THE WARMER DAYS FOR A WHILE...AT LEAST
ACROSS SW MN AND NW IA...WHILE LOOKS A BIT MORE CERTAIN WITH
VEERING LOW LEVEL FLOW THAT THE WEST WILL BREAK OUT MORE READILY.
FOR NOW...HAVE SOME READINGS APPROACHING 90 IN THE WEST...AND HAVE
LOWER TO MID 80S IN THE EAST. WITH THE WARMER AND MUCH MORE HUMID
AIR MASS...THERMODYNAMICS PROFILES ARE CONCERNING GIVEN THE
3000-3500 J/KG MEAN CAPE BETWEEN OPERATIONAL MODELS...UNTIL
CONSIDERING THAT MID LEVEL BOUNDARY PUSHED NORTHEAST DURING THE
MORNING...AND THERE IS A GOOD SOLID 75-150 J/KG CAP ON THINGS...
ALONG WITH NEXT TO NO LARGER SCALE LIFT FORCING.

IN FACT...SHOULD BE CAPPED ENOUGH THAT AS STRONG WAVE CRASHES
INTO THE FLAT RIDGE ON WEDNESDAY NIGHT...INITIATING CYCLOGENESIS
TO THE WEST AND NORTH AND FORCES A STRONG COLD FRONT THROUGH THE
DAKOTAS...THIS FRONT SHOULD REMAIN LARGELY INERT OVERNIGHT AND
EVEN WELL INTO THURSDAY AS IT PUSHES INTO NORTHWEST IOWA BY
AFTERNOON. NAM REMAINS CONSISTENT WITH TRACK RECORD AS SLOWEST...
GFS FASTEST...AND OTHERS VARYING PACE BETWEEN. ONLY BY THURSDAY
AFTERNOON IN THE SOUTHEAST CWA AS MORE ORGANIZED AREA OF POST
FRONTAL Q VECTOR SUPPORT SWINGS OUT ACROSS THE BOUNDARY. SHOULD
GET A GOOD INCREASE IN PRECIPITATION ALONG AND POST FRONTAL DURING
THE EVENING...WHICH WILL THEN BUILD SOUTH AS STRONG LOW LEVEL
NORTHERLY DRYING WITH AGEOSTROPHIC SUPPORT OF JET ENTRANCE.

FOR THE MOST PART...HAVE LEFT THE REMAINING THREE DAYS OF THE
EXTENDED DRY AS SURFACE RIDGE TO THE NORTH WEDGES A GOOD DOSE OF
LOW LEVEL DRY AIR INTO THE REGION. SEVERAL SOLUTIONS ATTEMPT TO
BRING ANOTHER POST FRONTAL WAVE WITH A LITTLE MID LEVEL MOISTURE
POOLING AROUND THE START OF THE WEEKEND...BUT WITH MODELS
UNCERTAIN ON TIMING ON TOP OF THIS LOW LEVEL DRY AIR...DID NOT
MAKE SENSE TO ADD IN ANY LOWER CHANCE POPS AT THIS TIME. PERIOD OF
FRIDAY THROUGH SUNDAY WILL REMAIN COOL...WITH HIGHS IN THE UPPER
60S TO MID 70S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1232 PM CDT MON SEP 1 2014

FOCUS THIS SET OF TAFS WAS THE CONVECTION THAT IS EXPECTED TO
DEVELOP ACROSS WEST CENTRAL SOUTH DAKOTA THIS AFTERNOON...AND
SPREAD EAST OVERNIGHT. HAVE ADDED HIGH BASED SHOWERS TO THE
FORECAST..THOUGH LIMITED INSTABILITY MAY LEAD TO A RUMBLE OF
THUNDER OR TWO AT TAF SITES. WESTERLY FLOW PREVAILS THROUGH THE
PERIOD...GENERALLY REMAINLY AT OR BELOW 10 KNOTS.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...





000
FXUS63 KFSD 011123
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
623 AM CDT MON SEP 1 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM CDT MON SEP 1 2014

UPPER LOW OVER THE CWA EARLY THIS MORNING GENERATING ISOLATED TO
SCATTERED SHOWERS. THESE ARE IN A WEAKENING STATE...AND THINKING
SHOULD GENERALLY BE DRY BY 12Z. WILL LIKELY SEE SOME CU AND
EVENTUALLY SOME CIRRUS MOVING IN FROM THE WEST TODAY...BUT SHOULD
GENERALLY BE A PARTLY TO MOSTLY SUNNY DAY. BASED ON THERMAL FIELDS
AND EXPECTED SUNSHINE...DID BUMP UP HIGHS A BIT...LOOKING FOR MID TO
UPPER 70S OVER THE AREA. A WAVE CURRENTLY ENTERING WYOMING WILL
QUICKLY PUSH EAST TODAY...MOVING OVER OUR AREA LATER THIS AFTERNOON
AND EVENING. PRETTY GOOD UPPER LEVEL FORCING WITH THIS WAVE...BUT WE
LACK A LOW LEVEL FORCING MECHANISM. CAP IS RELATIVELY SMALL...BUT
WITHOUT THIS FORCING MECHANISM...THINK IT WILL PROBABLY HOLD OVER
MOST OF THE AREA THIS AFTERNOON...KEEPING IT MAINLY DRY.

THERE DOES APPEAR TO BE AN AREA OF LOCALLY ENHANCED CONVERGENCE
ACROSS WESTERN MINNESOTA...AND HI RES MODELS ARE ALL SHOWING
DEVELOPMENT IN THIS AREA. THINK MOST OF THE SHOWERS AND STORMS IN
THIS AREA WILL PROBABLY STAY NORTHEAST OF OUR CWA...BUT INCLUDED
SOME LOW POPS NEAR MARSHALL. OTHER AREA WHERE STORMS MAY DEVELOP
THIS AFTERNOON IS ACROSS THE WESTERN PLAINS. THESE WILL TRACK
EAST...POSSIBLY APPROACHING CHAMBERLAIN AND GREGORY BY AROUND 0Z.
THUS ALSO WILL CARRY SOME POPS IN THIS AREA. GIVEN MINIMAL
CAPE...NOT MUCH OF A SEVERE THREAT...ALTHOUGH COULD BE SOME STRONG
WINDS WITH THE ACTIVITY ACROSS THE WESTERN PLAINS...POSSIBLY GETTING
INTO OUR SOUTH CENTRAL SOUTH DAKOTA COUNTIES. THINK MOST OF THE
ACTIVITY WILL DISSIPATE AFTER SUNSET...AND THUS WILL KEEP THE
FORECAST DRY IN BETWEEN THE TWO AREAS MENTIONED ABOVE. ALTHOUGH IF
WE HEAT ENOUGH...NOT OUT OF THE QUESTION WE COULD SEE AN ISOLATED
THUNDERSTORM JUST ABOUT ANYWHERE. SKIES CLEAR TONIGHT...BUT WE MAY
HOLD ON TO JUST ENOUGH OF A BREEZE TO PREVENT TEMPS FROM FALLING TOO
LOW...THOUGH STILL EXPECTING MID 50S.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 428 AM CDT MON SEP 1 2014

TUESDAY WILL OVERALL BE A PLEASANT DAY ACROSS THE AREA...AS
SURFACE RIDGE SLIPS SOUTHEAST...WITH ZONAL FLOW WORKING TOWARD
WEAK RIDGING. POTENTIAL FOR MID LEVEL BOUNDARY TO GET CAUGHT UP
JUST TO THE SOUTH OF THE AREA DURING THE DAY...SO COULD GET A FEW
HARMLESS MID CLOUDS ACROSS THE SOUTH...AND A SPILLOVER OF A FEW
HIGHER CLOUDS INTO THE NORTHERN AREAS. HIGHS WILL BE SEASONABLE IN
THE UPPER 70S AND LOWER 80S.

ON TUESDAY NIGHT...INCREASE IN MID LEVEL WARM AIR ADVECTION AND
PUSH OF THE ELEVATED MIXED LAYER INTO THE SOUTHWESTERN CWA. JUST
ENOUGH CONVERGENCE AND WEAK QG FORCING TO BE CONCERNED TOWARD THE
LATTER HALF OF THE NIGHT...AS BOUNDARY PUSHES SLOWLY NORTHEAST.ADDED
IN AN ISOLATED LEVEL POP FOR ELEVATED SHOWERS NORTH OF A HURON TO
SIOUX FALLS TO SPENCER LINE...BUT LOOKS LIKE ANY THUNDER IN A 50
J/KG MAX CAPE ENVIRONMENT WOULD BE EVEN MORE ROGUE THAN THE SHOWERS.
KEPT A SMALL LINGERING CHANCE DURING THE MORNING ACROSS SOUTHWEST
MINNESOTA AND EAST CENTRAL SD...BUT BOUNDARY SHOULD NOT WAIT
AROUND FOR LONG AS WEAK WAVE MOVES PAST.

WILL LIKELY HAVE SOME STRATUS BUILDING NORTHWARD ON TUESDAY NIGHT
ACROSS NEBRASKA...WITH A LATE NIGHT PULSE IN COVERAGE AS HIGHER
DEWPOINTS SNEAK IN BELOW WARMING TEMPS ALOFT. THIS STRATUS IS
ALMOST UNANIMOUSLY UNDERDONE IN MODEL SOLUTIONS...AND HAVE SOME
CONCERN THAT IT WILL NOT GO AWAY QUITE AS QUIETLY AS NAM/GFS/
CANADIAN/ECMWF SUGGEST. POTENTIAL IS THERE TO MESS UP WHAT WILL
LIKELY BE THE FINAL OF THE WARMER DAYS FOR A WHILE...AT LEAST
ACROSS SW MN AND NW IA...WHILE LOOKS A BIT MORE CERTAIN WITH
VEERING LOW LEVEL FLOW THAT THE WEST WILL BREAK OUT MORE READILY.
FOR NOW...HAVE SOME READINGS APPROACHING 90 IN THE WEST...AND HAVE
LOWER TO MID 80S IN THE EAST. WITH THE WARMER AND MUCH MORE HUMID
AIR MASS...THERMODYNAMICS PROFILES ARE CONCERNING GIVEN THE
3000-3500 J/KG MEAN CAPE BETWEEN OPERATIONAL MODELS...UNTIL
CONSIDERING THAT MID LEVEL BOUNDARY PUSHED NORTHEAST DURING THE
MORNING...AND THERE IS A GOOD SOLID 75-150 J/KG CAP ON THINGS...
ALONG WITH NEXT TO NO LARGER SCALE LIFT FORCING.

IN FACT...SHOULD BE CAPPED ENOUGH THAT AS STRONG WAVE CRASHES
INTO THE FLAT RIDGE ON WEDNESDAY NIGHT...INITIATING CYCLOGENESIS
TO THE WEST AND NORTH AND FORCES A STRONG COLD FRONT THROUGH THE
DAKOTAS...THIS FRONT SHOULD REMAIN LARGELY INERT OVERNIGHT AND
EVEN WELL INTO THURSDAY AS IT PUSHES INTO NORTHWEST IOWA BY
AFTERNOON. NAM REMAINS CONSISTENT WITH TRACK RECORD AS SLOWEST...
GFS FASTEST...AND OTHERS VARYING PACE BETWEEN. ONLY BY THURSDAY
AFTERNOON IN THE SOUTHEAST CWA AS MORE ORGANIZED AREA OF POST
FRONTAL Q VECTOR SUPPORT SWINGS OUT ACROSS THE BOUNDARY. SHOULD
GET A GOOD INCREASE IN PRECIPITATION ALONG AND POST FRONTAL DURING
THE EVENING...WHICH WILL THEN BUILD SOUTH AS STRONG LOW LEVEL
NORTHERLY DRYING WITH AGEOSTROPHIC SUPPORT OF JET ENTRANCE.

FOR THE MOST PART...HAVE LEFT THE REMAINING THREE DAYS OF THE
EXTENDED DRY AS SURFACE RIDGE TO THE NORTH WEDGES A GOOD DOSE OF
LOW LEVEL DRY AIR INTO THE REGION. SEVERAL SOLUTIONS ATTEMPT TO
BRING ANOTHER POST FRONTAL WAVE WITH A LITTLE MID LEVEL MOISTURE
POOLING AROUND THE START OF THE WEEKEND...BUT WITH MODELS
UNCERTAIN ON TIMING ON TOP OF THIS LOW LEVEL DRY AIR...DID NOT
MAKE SENSE TO ADD IN ANY LOWER CHANCE POPS AT THIS TIME. PERIOD OF
FRIDAY THROUGH SUNDAY WILL REMAIN COOL...WITH HIGHS IN THE UPPER
60S TO MID 70S.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 620 AM CDT MON SEP 1 2014

GENERALLY EXPECTING VFR CONDITIONS THROUGH THE PERIOD. COULD BE
ISOLATED TO SCATTERED THUNDERSTORMS THIS AFTERNOON AND
EVENING...GREATEST COVERAGE WEST OF THE JAMES RIVER. CONFIDENCE ON
COVERAGE AND TIMING TOO LOW TO INCLUDE MENTION IN THE TAFS AT
THIS TIME.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...CHENARD





000
FXUS63 KFSD 010929
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
429 AM CDT MON SEP 1 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM CDT MON SEP 1 2014

UPPER LOW OVER THE CWA EARLY THIS MORNING GENERATING ISOLATED TO
SCATTERED SHOWERS. THESE ARE IN A WEAKENING STATE...AND THINKING
SHOULD GENERALLY BE DRY BY 12Z. WILL LIKELY SEE SOME CU AND
EVENTUALLY SOME CIRRUS MOVING IN FROM THE WEST TODAY...BUT SHOULD
GENERALLY BE A PARTLY TO MOSTLY SUNNY DAY. BASED ON THERMAL FIELDS
AND EXPECTED SUNSHINE...DID BUMP UP HIGHS A BIT...LOOKING FOR MID TO
UPPER 70S OVER THE AREA. A WAVE CURRENTLY ENTERING WYOMING WILL
QUICKLY PUSH EAST TODAY...MOVING OVER OUR AREA LATER THIS AFTERNOON
AND EVENING. PRETTY GOOD UPPER LEVEL FORCING WITH THIS WAVE...BUT WE
LACK A LOW LEVEL FORCING MECHANISM. CAP IS RELATIVELY SMALL...BUT
WITHOUT THIS FORCING MECHANISM...THINK IT WILL PROBABLY HOLD OVER
MOST OF THE AREA THIS AFTERNOON...KEEPING IT MAINLY DRY.

THERE DOES APPEAR TO BE AN AREA OF LOCALLY ENHANCED CONVERGENCE
ACROSS WESTERN MINNESOTA...AND HI RES MODELS ARE ALL SHOWING
DEVELOPMENT IN THIS AREA. THINK MOST OF THE SHOWERS AND STORMS IN
THIS AREA WILL PROBABLY STAY NORTHEAST OF OUR CWA...BUT INCLUDED
SOME LOW POPS NEAR MARSHALL. OTHER AREA WHERE STORMS MAY DEVELOP
THIS AFTERNOON IS ACROSS THE WESTERN PLAINS. THESE WILL TRACK
EAST...POSSIBLY APPROACHING CHAMBERLAIN AND GREGORY BY AROUND 0Z.
THUS ALSO WILL CARRY SOME POPS IN THIS AREA. GIVEN MINIMAL
CAPE...NOT MUCH OF A SEVERE THREAT...ALTHOUGH COULD BE SOME STRONG
WINDS WITH THE ACTIVITY ACROSS THE WESTERN PLAINS...POSSIBLY GETTING
INTO OUR SOUTH CENTRAL SOUTH DAKOTA COUNTIES. THINK MOST OF THE
ACTIVITY WILL DISSIPATE AFTER SUNSET...AND THUS WILL KEEP THE
FORECAST DRY IN BETWEEN THE TWO AREAS MENTIONED ABOVE. ALTHOUGH IF
WE HEAT ENOUGH...NOT OUT OF THE QUESTION WE COULD SEE AN ISOLATED
THUNDERSTORM JUST ABOUT ANYWHERE. SKIES CLEAR TONIGHT...BUT WE MAY
HOLD ON TO JUST ENOUGH OF A BREEZE TO PREVENT TEMPS FROM FALLING TOO
LOW...THOUGH STILL EXPECTING MID 50S.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 428 AM CDT MON SEP 1 2014

TUESDAY WILL OVERALL BE A PLEASANT DAY ACROSS THE AREA...AS
SURFACE RIDGE SLIPS SOUTHEAST...WITH ZONAL FLOW WORKING TOWARD
WEAK RIDGING. POTENTIAL FOR MID LEVEL BOUNDARY TO GET CAUGHT UP
JUST TO THE SOUTH OF THE AREA DURING THE DAY...SO COULD GET A FEW
HARMLESS MID CLOUDS ACROSS THE SOUTH...AND A SPILLOVER OF A FEW
HIGHER CLOUDS INTO THE NORTHERN AREAS. HIGHS WILL BE SEASONABLE IN
THE UPPER 70S AND LOWER 80S.

ON TUESDAY NIGHT...INCREASE IN MID LEVEL WARM AIR ADVECTION AND
PUSH OF THE ELEVATED MIXED LAYER INTO THE SOUTHWESTERN CWA. JUST
ENOUGH CONVERGENCE AND WEAK QG FORCING TO BE CONCERNED TOWARD THE
LATTER HALF OF THE NIGHT...AS BOUNDARY PUSHES SLOWLY NORTHEAST.ADDED
IN AN ISOLATED LEVEL POP FOR ELEVATED SHOWERS NORTH OF A HURON TO
SIOUX FALLS TO SPENCER LINE...BUT LOOKS LIKE ANY THUNDER IN A 50
J/KG MAX CAPE ENVIRONMENT WOULD BE EVEN MORE ROGUE THAN THE SHOWERS.
KEPT A SMALL LINGERING CHANCE DURING THE MORNING ACROSS SOUTHWEST
MINNESOTA AND EAST CENTRAL SD...BUT BOUNDARY SHOULD NOT WAIT
AROUND FOR LONG AS WEAK WAVE MOVES PAST.

WILL LIKELY HAVE SOME STRATUS BUILDING NORTHWARD ON TUESDAY NIGHT
ACROSS NEBRASKA...WITH A LATE NIGHT PULSE IN COVERAGE AS HIGHER
DEWPOINTS SNEAK IN BELOW WARMING TEMPS ALOFT. THIS STRATUS IS
ALMOST UNANIMOUSLY UNDERDONE IN MODEL SOLUTIONS...AND HAVE SOME
CONCERN THAT IT WILL NOT GO AWAY QUITE AS QUIETLY AS NAM/GFS/
CANADIAN/ECMWF SUGGEST. POTENTIAL IS THERE TO MESS UP WHAT WILL
LIKELY BE THE FINAL OF THE WARMER DAYS FOR A WHILE...AT LEAST
ACROSS SW MN AND NW IA...WHILE LOOKS A BIT MORE CERTAIN WITH
VEERING LOW LEVEL FLOW THAT THE WEST WILL BREAK OUT MORE READILY.
FOR NOW...HAVE SOME READINGS APPROACHING 90 IN THE WEST...AND HAVE
LOWER TO MID 80S IN THE EAST. WITH THE WARMER AND MUCH MORE HUMID
AIR MASS...THERMODYNAMICS PROFILES ARE CONCERNING GIVEN THE
3000-3500 J/KG MEAN CAPE BETWEEN OPERATIONAL MODELS...UNTIL
CONSIDERING THAT MID LEVEL BOUNDARY PUSHED NORTHEAST DURING THE
MORNING...AND THERE IS A GOOD SOLID 75-150 J/KG CAP ON THINGS...
ALONG WITH NEXT TO NO LARGER SCALE LIFT FORCING.

IN FACT...SHOULD BE CAPPED ENOUGH THAT AS STRONG WAVE CRASHES
INTO THE FLAT RIDGE ON WEDNESDAY NIGHT...INITIATING CYCLOGENESIS
TO THE WEST AND NORTH AND FORCES A STRONG COLD FRONT THROUGH THE
DAKOTAS...THIS FRONT SHOULD REMAIN LARGELY INERT OVERNIGHT AND
EVEN WELL INTO THURSDAY AS IT PUSHES INTO NORTHWEST IOWA BY
AFTERNOON. NAM REMAINS CONSISTENT WITH TRACK RECORD AS SLOWEST...
GFS FASTEST...AND OTHERS VARYING PACE BETWEEN. ONLY BY THURSDAY
AFTERNOON IN THE SOUTHEAST CWA AS MORE ORGANIZED AREA OF POST
FRONTAL Q VECTOR SUPPORT SWINGS OUT ACROSS THE BOUNDARY. SHOULD
GET A GOOD INCREASE IN PRECIPITATION ALONG AND POST FRONTAL DURING
THE EVENING...WHICH WILL THEN BUILD SOUTH AS STRONG LOW LEVEL
NORTHERLY DRYING WITH AGEOSTROPHIC SUPPORT OF JET ENTRANCE.

FOR THE MOST PART...HAVE LEFT THE REMAINING THREE DAYS OF THE
EXTENDED DRY AS SURFACE RIDGE TO THE NORTH WEDGES A GOOD DOSE OF
LOW LEVEL DRY AIR INTO THE REGION. SEVERAL SOLUTIONS ATTEMPT TO
BRING ANOTHER POST FRONTAL WAVE WITH A LITTLE MID LEVEL MOISTURE
POOLING AROUND THE START OF THE WEEKEND...BUT WITH MODELS
UNCERTAIN ON TIMING ON TOP OF THIS LOW LEVEL DRY AIR...DID NOT
MAKE SENSE TO ADD IN ANY LOWER CHANCE POPS AT THIS TIME. PERIOD OF
FRIDAY THROUGH SUNDAY WILL REMAIN COOL...WITH HIGHS IN THE UPPER
60S TO MID 70S.



&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1137 PM CDT SUN AUG 31 2014

HIRES MODELS ALL POINT TO MORE SHOWERS DURING THE EARLY OVERNIGHT
HOURS AND RADAR BACKS UP WITH A FEW SHOWERS IN SOUTH CENTRAL SD.
HOWEVER...CONFIDENCE ISNT TOO HIGH THAT TAF LOCATIONS WILL
EXPERIENCE MEASURABLE RAIN. SO AT THIS POINT DID NOT NOT MENTION
CHANCE FOR -SHRA BUT DID INCLUDE A TEMPO GROUP FOR CLOUDS. AFTER
WAVE GOES THROUGH...SKIES SHOULD CLEAR BY DAWN AND SKIES WOULDREMAIN
THAT WAY THROUGH MOST OF THE DAY. NEXT CHANCE FOR -TSRA WILL BE
LATER IN THE DAY ON MONDAY...BUT ONLY MENTION A PROB30 AT KHON.
CHANCES FOR KFSD AND KSUX WILL BE LATER...MORE THAN LIKELY OUTSIDE
THIS TAF PERIOD.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...HEITKAMP





000
FXUS63 KFSD 010929
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
429 AM CDT MON SEP 1 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM CDT MON SEP 1 2014

UPPER LOW OVER THE CWA EARLY THIS MORNING GENERATING ISOLATED TO
SCATTERED SHOWERS. THESE ARE IN A WEAKENING STATE...AND THINKING
SHOULD GENERALLY BE DRY BY 12Z. WILL LIKELY SEE SOME CU AND
EVENTUALLY SOME CIRRUS MOVING IN FROM THE WEST TODAY...BUT SHOULD
GENERALLY BE A PARTLY TO MOSTLY SUNNY DAY. BASED ON THERMAL FIELDS
AND EXPECTED SUNSHINE...DID BUMP UP HIGHS A BIT...LOOKING FOR MID TO
UPPER 70S OVER THE AREA. A WAVE CURRENTLY ENTERING WYOMING WILL
QUICKLY PUSH EAST TODAY...MOVING OVER OUR AREA LATER THIS AFTERNOON
AND EVENING. PRETTY GOOD UPPER LEVEL FORCING WITH THIS WAVE...BUT WE
LACK A LOW LEVEL FORCING MECHANISM. CAP IS RELATIVELY SMALL...BUT
WITHOUT THIS FORCING MECHANISM...THINK IT WILL PROBABLY HOLD OVER
MOST OF THE AREA THIS AFTERNOON...KEEPING IT MAINLY DRY.

THERE DOES APPEAR TO BE AN AREA OF LOCALLY ENHANCED CONVERGENCE
ACROSS WESTERN MINNESOTA...AND HI RES MODELS ARE ALL SHOWING
DEVELOPMENT IN THIS AREA. THINK MOST OF THE SHOWERS AND STORMS IN
THIS AREA WILL PROBABLY STAY NORTHEAST OF OUR CWA...BUT INCLUDED
SOME LOW POPS NEAR MARSHALL. OTHER AREA WHERE STORMS MAY DEVELOP
THIS AFTERNOON IS ACROSS THE WESTERN PLAINS. THESE WILL TRACK
EAST...POSSIBLY APPROACHING CHAMBERLAIN AND GREGORY BY AROUND 0Z.
THUS ALSO WILL CARRY SOME POPS IN THIS AREA. GIVEN MINIMAL
CAPE...NOT MUCH OF A SEVERE THREAT...ALTHOUGH COULD BE SOME STRONG
WINDS WITH THE ACTIVITY ACROSS THE WESTERN PLAINS...POSSIBLY GETTING
INTO OUR SOUTH CENTRAL SOUTH DAKOTA COUNTIES. THINK MOST OF THE
ACTIVITY WILL DISSIPATE AFTER SUNSET...AND THUS WILL KEEP THE
FORECAST DRY IN BETWEEN THE TWO AREAS MENTIONED ABOVE. ALTHOUGH IF
WE HEAT ENOUGH...NOT OUT OF THE QUESTION WE COULD SEE AN ISOLATED
THUNDERSTORM JUST ABOUT ANYWHERE. SKIES CLEAR TONIGHT...BUT WE MAY
HOLD ON TO JUST ENOUGH OF A BREEZE TO PREVENT TEMPS FROM FALLING TOO
LOW...THOUGH STILL EXPECTING MID 50S.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 428 AM CDT MON SEP 1 2014

TUESDAY WILL OVERALL BE A PLEASANT DAY ACROSS THE AREA...AS
SURFACE RIDGE SLIPS SOUTHEAST...WITH ZONAL FLOW WORKING TOWARD
WEAK RIDGING. POTENTIAL FOR MID LEVEL BOUNDARY TO GET CAUGHT UP
JUST TO THE SOUTH OF THE AREA DURING THE DAY...SO COULD GET A FEW
HARMLESS MID CLOUDS ACROSS THE SOUTH...AND A SPILLOVER OF A FEW
HIGHER CLOUDS INTO THE NORTHERN AREAS. HIGHS WILL BE SEASONABLE IN
THE UPPER 70S AND LOWER 80S.

ON TUESDAY NIGHT...INCREASE IN MID LEVEL WARM AIR ADVECTION AND
PUSH OF THE ELEVATED MIXED LAYER INTO THE SOUTHWESTERN CWA. JUST
ENOUGH CONVERGENCE AND WEAK QG FORCING TO BE CONCERNED TOWARD THE
LATTER HALF OF THE NIGHT...AS BOUNDARY PUSHES SLOWLY NORTHEAST.ADDED
IN AN ISOLATED LEVEL POP FOR ELEVATED SHOWERS NORTH OF A HURON TO
SIOUX FALLS TO SPENCER LINE...BUT LOOKS LIKE ANY THUNDER IN A 50
J/KG MAX CAPE ENVIRONMENT WOULD BE EVEN MORE ROGUE THAN THE SHOWERS.
KEPT A SMALL LINGERING CHANCE DURING THE MORNING ACROSS SOUTHWEST
MINNESOTA AND EAST CENTRAL SD...BUT BOUNDARY SHOULD NOT WAIT
AROUND FOR LONG AS WEAK WAVE MOVES PAST.

WILL LIKELY HAVE SOME STRATUS BUILDING NORTHWARD ON TUESDAY NIGHT
ACROSS NEBRASKA...WITH A LATE NIGHT PULSE IN COVERAGE AS HIGHER
DEWPOINTS SNEAK IN BELOW WARMING TEMPS ALOFT. THIS STRATUS IS
ALMOST UNANIMOUSLY UNDERDONE IN MODEL SOLUTIONS...AND HAVE SOME
CONCERN THAT IT WILL NOT GO AWAY QUITE AS QUIETLY AS NAM/GFS/
CANADIAN/ECMWF SUGGEST. POTENTIAL IS THERE TO MESS UP WHAT WILL
LIKELY BE THE FINAL OF THE WARMER DAYS FOR A WHILE...AT LEAST
ACROSS SW MN AND NW IA...WHILE LOOKS A BIT MORE CERTAIN WITH
VEERING LOW LEVEL FLOW THAT THE WEST WILL BREAK OUT MORE READILY.
FOR NOW...HAVE SOME READINGS APPROACHING 90 IN THE WEST...AND HAVE
LOWER TO MID 80S IN THE EAST. WITH THE WARMER AND MUCH MORE HUMID
AIR MASS...THERMODYNAMICS PROFILES ARE CONCERNING GIVEN THE
3000-3500 J/KG MEAN CAPE BETWEEN OPERATIONAL MODELS...UNTIL
CONSIDERING THAT MID LEVEL BOUNDARY PUSHED NORTHEAST DURING THE
MORNING...AND THERE IS A GOOD SOLID 75-150 J/KG CAP ON THINGS...
ALONG WITH NEXT TO NO LARGER SCALE LIFT FORCING.

IN FACT...SHOULD BE CAPPED ENOUGH THAT AS STRONG WAVE CRASHES
INTO THE FLAT RIDGE ON WEDNESDAY NIGHT...INITIATING CYCLOGENESIS
TO THE WEST AND NORTH AND FORCES A STRONG COLD FRONT THROUGH THE
DAKOTAS...THIS FRONT SHOULD REMAIN LARGELY INERT OVERNIGHT AND
EVEN WELL INTO THURSDAY AS IT PUSHES INTO NORTHWEST IOWA BY
AFTERNOON. NAM REMAINS CONSISTENT WITH TRACK RECORD AS SLOWEST...
GFS FASTEST...AND OTHERS VARYING PACE BETWEEN. ONLY BY THURSDAY
AFTERNOON IN THE SOUTHEAST CWA AS MORE ORGANIZED AREA OF POST
FRONTAL Q VECTOR SUPPORT SWINGS OUT ACROSS THE BOUNDARY. SHOULD
GET A GOOD INCREASE IN PRECIPITATION ALONG AND POST FRONTAL DURING
THE EVENING...WHICH WILL THEN BUILD SOUTH AS STRONG LOW LEVEL
NORTHERLY DRYING WITH AGEOSTROPHIC SUPPORT OF JET ENTRANCE.

FOR THE MOST PART...HAVE LEFT THE REMAINING THREE DAYS OF THE
EXTENDED DRY AS SURFACE RIDGE TO THE NORTH WEDGES A GOOD DOSE OF
LOW LEVEL DRY AIR INTO THE REGION. SEVERAL SOLUTIONS ATTEMPT TO
BRING ANOTHER POST FRONTAL WAVE WITH A LITTLE MID LEVEL MOISTURE
POOLING AROUND THE START OF THE WEEKEND...BUT WITH MODELS
UNCERTAIN ON TIMING ON TOP OF THIS LOW LEVEL DRY AIR...DID NOT
MAKE SENSE TO ADD IN ANY LOWER CHANCE POPS AT THIS TIME. PERIOD OF
FRIDAY THROUGH SUNDAY WILL REMAIN COOL...WITH HIGHS IN THE UPPER
60S TO MID 70S.



&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1137 PM CDT SUN AUG 31 2014

HIRES MODELS ALL POINT TO MORE SHOWERS DURING THE EARLY OVERNIGHT
HOURS AND RADAR BACKS UP WITH A FEW SHOWERS IN SOUTH CENTRAL SD.
HOWEVER...CONFIDENCE ISNT TOO HIGH THAT TAF LOCATIONS WILL
EXPERIENCE MEASURABLE RAIN. SO AT THIS POINT DID NOT NOT MENTION
CHANCE FOR -SHRA BUT DID INCLUDE A TEMPO GROUP FOR CLOUDS. AFTER
WAVE GOES THROUGH...SKIES SHOULD CLEAR BY DAWN AND SKIES WOULDREMAIN
THAT WAY THROUGH MOST OF THE DAY. NEXT CHANCE FOR -TSRA WILL BE
LATER IN THE DAY ON MONDAY...BUT ONLY MENTION A PROB30 AT KHON.
CHANCES FOR KFSD AND KSUX WILL BE LATER...MORE THAN LIKELY OUTSIDE
THIS TAF PERIOD.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...HEITKAMP




000
FXUS63 KFSD 010442
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1142 PM CDT SUN AUG 31 2014

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 309 PM CDT SUN AUG 31 2014

JUST WEST OF MARSHALL MN TO SIOUX FALLS SD TO JUST WEST OF SIOUX
CITY. EXPECT DEEP CONVECTION TO BE FOCUSED ALONG AND EAST OF THE
BOUNDARY. HAVE ADJUSTED THE HWO TO FOCUS ON THE HIGHWAY 60 AND EAST
CORRIDOR...WHERE STORMS ARE EXPECTED TO DEVELOP AROUND 22Z WITH THE
POTENTIAL FOR LARGE HAIL...DAMAGING WINDS AND ISOLATE TORNADOES.
WITH NEAR SURFACE LAYER FLOW BECOMING SOUTHWEST...STILL NOT A TON OF
DIRECTIONAL SHEAR...BUT STILL SOME DECENT SPEED SHEAR TO AID IN
STORM ORGANIZATION.  BETTER BACKED FLOW FURTHER TO THE SOUTH ALONG
THE I-80 CORRIDOR IN WESTERN AND CENTRAL IOWA AIDING IN BETTER
FELICITY. DO NOT EXPECT THIS BOUNDARY TO WORK MUCH FURTHER NORTH
THAN HIGHWAY 30 SOUTH OF OUR FORECAST AREA...THEREFORE...MAIN SEVERE
WEATHER THREATS SHOULD BE PRIMARILY WIND AND HAIL DRIVEN FOR THE
EASTERN PORTIONS OF OUR FORECAST AREA.  WITH AFOREMENTIONED SPEED
SHEAR AND CAPE VALUES AROUND 1500-2000 J/KG AND MINIMAL CAP...EXPECT
STORMS TO DEVELOP AS SHORTWAVE LIFTING FROM SOUTHEAST AIDS IN UPPER
LEVEL SUPPORT AND LIFT.

EXPECT SEVERE THREAT TO SHIFT EAST OF THE AREA AFTER 03Z.  STILL MAY
HAVE SOME POST FRONTAL SHOWERS SHIFT THROUGH THE AREA OVERNIGHT.

COOLER AND DRIER CONDITIONS ARE EXPECTED ON MONDAY...WITH NEAR
NORMAL HIGHS IN THE MID AND UPPER 70S.  FAST MOVING SHORT WAVE
APPROACHING FROM THE WEST MAY GENERATE A FEW LATE AFTERNOON
THUNDERSTORMS ACROSS CENTRAL SOUTH DAKOTA...BUT SHOULD REMAIN BELOW
SEVERE LIMITS WITH LIMITED AMOUNTS OF MOISTURE AND INSTABILITY.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 309 PM CDT SUN AUG 31 2014

A WEAK WAVE WILL MOVE THROUGH ON MONDAY NIGHT AND WILL CONTINUE WITH
MAINLY ISOLATED SHOWERS/THUNDER POTENTIAL. LOOKS LIKE AMOUNTS WOULD
BE LIGHT AND NOTHING SEVERE EXPECTED. LOWS MAINLY IN THE 50S.

TUESDAY LOOKS LIKE A VERY NICE DAY WITH RELATIVELY LOW
HUMIDITY...WINDS MAINLY LESS THAN 15 MPH AND HIGHS IN THE UPPER 70S
TO LOWER 80S.

TUESDAY NIGHT INTO WEDNESDAY WILL SEE SOUTHERLY RETURN FLOW DEVELOP
WITH INCREASING HUMIDITY. INCREASED LOW TEMPERATURES ON TUESDAY
NIGHT AS THE CONSRAW OUTPUT GENERALLY MORE ACCURATE WITH STRONGER
WINDS...SO MAINLY LOWER TO MIDDLE 60S. WARM AIR WILL SURGE NORTH AS
WELL SO WITH HIGHS IN THE MID AND UPPER 80S AND DEW POINTS IN THE
UPPER 60S TO AROUND 70 AFTERNOON HEAT INDICES WILL LIKELY REACH THE
MID 90S IN SOME SPOTS. WARM ADVECTION AND A WEAK WAVE ALSO SUPPORT
THE THREAT FOR ISOLATED SHOWERS AND THUNDERSTORMS IN MAINLY
SOUTHWEST MINNESOTA SO WILL KEEP A LOW CHANCE IN THERE.

IN THE OUTER PERIODS (THURSDAY THROUGH SUNDAY)...THE OVERALL PATTERN
LOOKS VERY EARLY FALL LIKE WITH A TROUGH OVER THE WEST COAST AND
STRONG WEST TO SOUTHWEST FLOW OVER THE NORTHERN PLAINS. WEDNESDAY
NIGHT INTO THURSDAY STILL SEES A FRONT COMING INTO THE AREA WHICH
SHOULD LEAD TOWARDS A WARM THURSDAY MORNING AND STILL WARM
THURSDAY...BUT WITH MODIFYING OR COOLING LOW LEVEL TEMPERATURES.
THIS COOLER AIR REMAINS LOCKED IN PLACE THROUGH AT LEAST SATURDAY.
POSSIBLY A BIT BREEZY ON FRIDAY BUT LIKELY LIGHT WINDS ON SATURDAY.
MODELS DIFFER A BIT ON PATTERN LEADING INTO SUNDAY WITH SOME LOCKING
THE COOL AIR IN THROUGH SUNDAY WHILE WEAK RETURN FLOW SETS UP ON A
FEW OTHERS. EITHER WAY LIKELY BELOW NORMAL TEMPERATURES FRIDAY INTO
SUNDAY. STILL REMAINS A DECENT CHANCE FOR SHOWERS AND ISOLATED
THUNDERSTORMS THURSDAY NIGHT INTO FRIDAY AS A GOOD RIGHT ENTRANCE
REGION FOLLOWS THE SURFACE COLD FRONT WITH WHAT APPEARS TO BE GOOD
MID LEVEL MOISTURE ON MOST OF THE MODELS. MAY UP POPS A BIT DURING
THIS TIME. MORE THAN LIKELY THE WEEKEND WILL REMAIN DRY AS HIGH
PRESSURE TRYS TO STAY IN CONTROL.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1137 PM CDT SUN AUG 31 2014

HIRES MODELS ALL POINT TO MORE SHOWERS DURING THE EARLY OVERNIGHT
HOURS AND RADAR BACKS UP WITH A FEW SHOWERS IN SOUTH CENTRAL SD.
HOWEVER...CONFIDENCE ISNT TOO HIGH THAT TAF LOCATIONS WILL
EXPERIENCE MEASURABLE RAIN. SO AT THIS POINT DIDN NOT MENTION
CHANCE FOR -SHRA BUT DID INCLUDE A TEMPO GROUP FOR CLOUDS. AFTER
WAVE GOES THROUGH...SKIES SHOULD CLEAR BY DAWN AND SKIES WHOULD
REMAIN THAT WAY THROUGH MOST OF THE DAY. NEXT CHANCE FOR -TSRA
WILL BE LATER IN THE DAY ON MONDAY...BUT ONLY MENTION A PROB30 AT
KHON. CHANCES FOR KFSD AND KSUX WILL BE LATER...MORE THAN LIKELY
OUTSIDE THIS TAF PERIOD.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...
LONG TERM...08
AVIATION...HEITKAMP





000
FXUS63 KFSD 010442
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1142 PM CDT SUN AUG 31 2014

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 309 PM CDT SUN AUG 31 2014

JUST WEST OF MARSHALL MN TO SIOUX FALLS SD TO JUST WEST OF SIOUX
CITY. EXPECT DEEP CONVECTION TO BE FOCUSED ALONG AND EAST OF THE
BOUNDARY. HAVE ADJUSTED THE HWO TO FOCUS ON THE HIGHWAY 60 AND EAST
CORRIDOR...WHERE STORMS ARE EXPECTED TO DEVELOP AROUND 22Z WITH THE
POTENTIAL FOR LARGE HAIL...DAMAGING WINDS AND ISOLATE TORNADOES.
WITH NEAR SURFACE LAYER FLOW BECOMING SOUTHWEST...STILL NOT A TON OF
DIRECTIONAL SHEAR...BUT STILL SOME DECENT SPEED SHEAR TO AID IN
STORM ORGANIZATION.  BETTER BACKED FLOW FURTHER TO THE SOUTH ALONG
THE I-80 CORRIDOR IN WESTERN AND CENTRAL IOWA AIDING IN BETTER
FELICITY. DO NOT EXPECT THIS BOUNDARY TO WORK MUCH FURTHER NORTH
THAN HIGHWAY 30 SOUTH OF OUR FORECAST AREA...THEREFORE...MAIN SEVERE
WEATHER THREATS SHOULD BE PRIMARILY WIND AND HAIL DRIVEN FOR THE
EASTERN PORTIONS OF OUR FORECAST AREA.  WITH AFOREMENTIONED SPEED
SHEAR AND CAPE VALUES AROUND 1500-2000 J/KG AND MINIMAL CAP...EXPECT
STORMS TO DEVELOP AS SHORTWAVE LIFTING FROM SOUTHEAST AIDS IN UPPER
LEVEL SUPPORT AND LIFT.

EXPECT SEVERE THREAT TO SHIFT EAST OF THE AREA AFTER 03Z.  STILL MAY
HAVE SOME POST FRONTAL SHOWERS SHIFT THROUGH THE AREA OVERNIGHT.

COOLER AND DRIER CONDITIONS ARE EXPECTED ON MONDAY...WITH NEAR
NORMAL HIGHS IN THE MID AND UPPER 70S.  FAST MOVING SHORT WAVE
APPROACHING FROM THE WEST MAY GENERATE A FEW LATE AFTERNOON
THUNDERSTORMS ACROSS CENTRAL SOUTH DAKOTA...BUT SHOULD REMAIN BELOW
SEVERE LIMITS WITH LIMITED AMOUNTS OF MOISTURE AND INSTABILITY.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 309 PM CDT SUN AUG 31 2014

A WEAK WAVE WILL MOVE THROUGH ON MONDAY NIGHT AND WILL CONTINUE WITH
MAINLY ISOLATED SHOWERS/THUNDER POTENTIAL. LOOKS LIKE AMOUNTS WOULD
BE LIGHT AND NOTHING SEVERE EXPECTED. LOWS MAINLY IN THE 50S.

TUESDAY LOOKS LIKE A VERY NICE DAY WITH RELATIVELY LOW
HUMIDITY...WINDS MAINLY LESS THAN 15 MPH AND HIGHS IN THE UPPER 70S
TO LOWER 80S.

TUESDAY NIGHT INTO WEDNESDAY WILL SEE SOUTHERLY RETURN FLOW DEVELOP
WITH INCREASING HUMIDITY. INCREASED LOW TEMPERATURES ON TUESDAY
NIGHT AS THE CONSRAW OUTPUT GENERALLY MORE ACCURATE WITH STRONGER
WINDS...SO MAINLY LOWER TO MIDDLE 60S. WARM AIR WILL SURGE NORTH AS
WELL SO WITH HIGHS IN THE MID AND UPPER 80S AND DEW POINTS IN THE
UPPER 60S TO AROUND 70 AFTERNOON HEAT INDICES WILL LIKELY REACH THE
MID 90S IN SOME SPOTS. WARM ADVECTION AND A WEAK WAVE ALSO SUPPORT
THE THREAT FOR ISOLATED SHOWERS AND THUNDERSTORMS IN MAINLY
SOUTHWEST MINNESOTA SO WILL KEEP A LOW CHANCE IN THERE.

IN THE OUTER PERIODS (THURSDAY THROUGH SUNDAY)...THE OVERALL PATTERN
LOOKS VERY EARLY FALL LIKE WITH A TROUGH OVER THE WEST COAST AND
STRONG WEST TO SOUTHWEST FLOW OVER THE NORTHERN PLAINS. WEDNESDAY
NIGHT INTO THURSDAY STILL SEES A FRONT COMING INTO THE AREA WHICH
SHOULD LEAD TOWARDS A WARM THURSDAY MORNING AND STILL WARM
THURSDAY...BUT WITH MODIFYING OR COOLING LOW LEVEL TEMPERATURES.
THIS COOLER AIR REMAINS LOCKED IN PLACE THROUGH AT LEAST SATURDAY.
POSSIBLY A BIT BREEZY ON FRIDAY BUT LIKELY LIGHT WINDS ON SATURDAY.
MODELS DIFFER A BIT ON PATTERN LEADING INTO SUNDAY WITH SOME LOCKING
THE COOL AIR IN THROUGH SUNDAY WHILE WEAK RETURN FLOW SETS UP ON A
FEW OTHERS. EITHER WAY LIKELY BELOW NORMAL TEMPERATURES FRIDAY INTO
SUNDAY. STILL REMAINS A DECENT CHANCE FOR SHOWERS AND ISOLATED
THUNDERSTORMS THURSDAY NIGHT INTO FRIDAY AS A GOOD RIGHT ENTRANCE
REGION FOLLOWS THE SURFACE COLD FRONT WITH WHAT APPEARS TO BE GOOD
MID LEVEL MOISTURE ON MOST OF THE MODELS. MAY UP POPS A BIT DURING
THIS TIME. MORE THAN LIKELY THE WEEKEND WILL REMAIN DRY AS HIGH
PRESSURE TRYS TO STAY IN CONTROL.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1137 PM CDT SUN AUG 31 2014

HIRES MODELS ALL POINT TO MORE SHOWERS DURING THE EARLY OVERNIGHT
HOURS AND RADAR BACKS UP WITH A FEW SHOWERS IN SOUTH CENTRAL SD.
HOWEVER...CONFIDENCE ISNT TOO HIGH THAT TAF LOCATIONS WILL
EXPERIENCE MEASURABLE RAIN. SO AT THIS POINT DIDN NOT MENTION
CHANCE FOR -SHRA BUT DID INCLUDE A TEMPO GROUP FOR CLOUDS. AFTER
WAVE GOES THROUGH...SKIES SHOULD CLEAR BY DAWN AND SKIES WHOULD
REMAIN THAT WAY THROUGH MOST OF THE DAY. NEXT CHANCE FOR -TSRA
WILL BE LATER IN THE DAY ON MONDAY...BUT ONLY MENTION A PROB30 AT
KHON. CHANCES FOR KFSD AND KSUX WILL BE LATER...MORE THAN LIKELY
OUTSIDE THIS TAF PERIOD.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...
LONG TERM...08
AVIATION...HEITKAMP




000
FXUS63 KFSD 312010
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
310 PM CDT SUN AUG 31 2014

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 309 PM CDT SUN AUG 31 2014

JUST WEST OF MARSHALL MN TO SIOUX FALLS SD TO JUST WEST OF SIOUX
CITY. EXPECT DEEP CONVECTION TO BE FOCUSED ALONG AND EAST OF THE
BOUNDARY. HAVE ADJUSTED THE HWO TO FOCUS ON THE HIGHWAY 60 AND EAST
CORRIDOR...WHERE STORMS ARE EXPECTED TO DEVELOP AROUND 22Z WITH THE
POTENTIAL FOR LARGE HAIL...DAMAGING WINDS AND ISOLATE TORNADOES.
WITH NEAR SURFACE LAYER FLOW BECOMING SOUTHWEST...STILL NOT A TON OF
DIRECTIONAL SHEAR...BUT STILL SOME DECENT SPEED SHEAR TO AID IN
STORM ORGANIZATION.  BETTER BACKED FLOW FURTHER TO THE SOUTH ALONG
THE I-80 CORRIDOR IN WESTERN AND CENTRAL IOWA AIDING IN BETTER
FELICITY. DO NOT EXPECT THIS BOUNDARY TO WORK MUCH FURTHER NORTH
THAN HIGHWAY 30 SOUTH OF OUR FORECAST AREA...THEREFORE...MAIN SEVERE
WEATHER THREATS SHOULD BE PRIMARILY WIND AND HAIL DRIVEN FOR THE
EASTERN PORTIONS OF OUR FORECAST AREA.  WITH AFOREMENTIONED SPEED
SHEAR AND CAPE VALUES AROUND 1500-2000 J/KG AND MINIMAL CAP...EXPECT
STORMS TO DEVELOP AS SHORTWAVE LIFTING FROM SOUTHEAST AIDS IN UPPER
LEVEL SUPPORT AND LIFT.

EXPECT SEVERE THREAT TO SHIFT EAST OF THE AREA AFTER 03Z.  STILL MAY
HAVE SOME POST FRONTAL SHOWERS SHIFT THROUGH THE AREA OVERNIGHT.

COOLER AND DRIER CONDITIONS ARE EXPECTED ON MONDAY...WITH NEAR
NORMAL HIGHS IN THE MID AND UPPER 70S.  FAST MOVING SHORT WAVE
APPROACHING FROM THE WEST MAY GENERATE A FEW LATE AFTERNOON
THUNDERSTORMS ACROSS CENTRAL SOUTH DAKOTA...BUT SHOULD REMAIN BELOW
SEVERE LIMITS WITH LIMITED AMOUNTS OF MOISTURE AND INSTABILITY.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 309 PM CDT SUN AUG 31 2014

A WEAK WAVE WILL MOVE THROUGH ON MONDAY NIGHT AND WILL CONTINUE WITH
MAINLY ISOLATED SHOWERS/THUNDER POTENTIAL. LOOKS LIKE AMOUNTS WOULD
BE LIGHT AND NOTHING SEVERE EXPECTED. LOWS MAINLY IN THE 50S.

TUESDAY LOOKS LIKE A VERY NICE DAY WITH RELATIVELY LOW
HUMIDITY...WINDS MAINLY LESS THAN 15 MPH AND HIGHS IN THE UPPER 70S
TO LOWER 80S.

TUESDAY NIGHT INTO WEDNESDAY WILL SEE SOUTHERLY RETURN FLOW DEVELOP
WITH INCREASING HUMIDITY. INCREASED LOW TEMPERATURES ON TUESDAY
NIGHT AS THE CONSRAW OUTPUT GENERALLY MORE ACCURATE WITH STRONGER
WINDS...SO MAINLY LOWER TO MIDDLE 60S. WARM AIR WILL SURGE NORTH AS
WELL SO WITH HIGHS IN THE MID AND UPPER 80S AND DEW POINTS IN THE
UPPER 60S TO AROUND 70 AFTERNOON HEAT INDICES WILL LIKELY REACH THE
MID 90S IN SOME SPOTS. WARM ADVECTION AND A WEAK WAVE ALSO SUPPORT
THE THREAT FOR ISOLATED SHOWERS AND THUNDERSTORMS IN MAINLY
SOUTHWEST MINNESOTA SO WILL KEEP A LOW CHANCE IN THERE.

IN THE OUTER PERIODS (THURSDAY THROUGH SUNDAY)...THE OVERALL PATTERN
LOOKS VERY EARLY FALL LIKE WITH A TROUGH OVER THE WEST COAST AND
STRONG WEST TO SOUTHWEST FLOW OVER THE NORTHERN PLAINS. WEDNESDAY
NIGHT INTO THURSDAY STILL SEES A FRONT COMING INTO THE AREA WHICH
SHOULD LEAD TOWARDS A WARM THURSDAY MORNING AND STILL WARM
THURSDAY...BUT WITH MODIFYING OR COOLING LOW LEVEL TEMPERATURES.
THIS COOLER AIR REMAINS LOCKED IN PLACE THROUGH AT LEAST SATURDAY.
POSSIBLY A BIT BREEZY ON FRIDAY BUT LIKELY LIGHT WINDS ON SATURDAY.
MODELS DIFFER A BIT ON PATTERN LEADING INTO SUNDAY WITH SOME LOCKING
THE COOL AIR IN THROUGH SUNDAY WHILE WEAK RETURN FLOW SETS UP ON A
FEW OTHERS. EITHER WAY LIKELY BELOW NORMAL TEMPERATURES FRIDAY INTO
SUNDAY. STILL REMAINS A DECENT CHANCE FOR SHOWERS AND ISOLATED
THUNDERSTORMS THURSDAY NIGHT INTO FRIDAY AS A GOOD RIGHT ENTRANCE
REGION FOLLOWS THE SURFACE COLD FRONT WITH WHAT APPEARS TO BE GOOD
MID LEVEL MOISTURE ON MOST OF THE MODELS. MAY UP POPS A BIT DURING
THIS TIME. MORE THAN LIKELY THE WEEKEND WILL REMAIN DRY AS HIGH
PRESSURE TRYS TO STAY IN CONTROL.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1238 PM CDT SUN AUG 31 2014
CONVECTION IS THE PRIMARY AVIATION CONCERN FOR THE 18Z TAF
ISSUANCE. MODEL TRENDS HAVE BEEN TO ACCELERATE THE FRONT
SLIGHTLY...SO HAVE SHIFTED THE FOCUS FOR DEEP COMVECTION LATE THIS
AFTERNOON TO MAINLY NORTHWEST IOWA ALONG AND AHEAD OF A COLD
FRONT PUSHING THROUGH THE REGION. THESE STORMS WILL BE CAPABLE OF
PRODUCING LARGE HAIL...DAMAGING WINDS AND AN ISOLATED TORNADO OR
TWO. SIOUX CITY APPEARS TO BE ON THE WESTERN EDGE OF THE MAIN
THREAT AREA.

THERE REMAINS AN OUTSIDE POTENTIAL OF MVFR CEILING/VISIBILITY
THREAT WORKING SOUTHWARD BEHIND MAIN UPPER TROUGH AFTER 06Z INTO
KHON AND AFTER 09Z AT KFSD...BUT HAVE LEFT CLEAR AS APPEARS LOW
PROBABILITY FOR NOW.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...
LONG TERM...08
AVIATION...




000
FXUS63 KFSD 311745
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1245 PM CDT SUN AUG 31 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM CDT SUN AUG 31 2014

GREATEST CONCERN TODAY IS WITH THE SEVERE WEATHER POTENTIAL LATER
TODAY.

LEADING UPPER WAVE LIFTING THROUGH THE NORTHERN PLAINS AT PRESENT.
ENERGY WITH SYSTEM IS PULLING MOSTLY TOWARD NORTH DAKOTA...AND AS AS
RESULT HAVE SEEN EARLIER STRONGER ACTIVITY ACROSS WESTERN SOUTH
DAKOTA REALLY WEAKEN HEADING INTO SOUTHEAST SOUTH DAKOTA. STRONG LOW
LEVEL JET EXHIBITING MUCH BETTER CONVERGENCE TO THE NORTH...AND ON
VEERING NOSE ARE STARTING TO SEE EXTENSION OF MID CLOUDS SOUTHWARD
ACROSS SW MN AND NW IA...WHICH VERY WELL COULD NOT HAVE A CHANCE TO
ACTIVATE TO A BETTER CONVECTIVE BAND BEFORE EXITING THE FSD CWA...
PER SEVERAL RECENT HIGH RESOLUTION MODEL RUNS. WHAT REMAINS IN THE
AREA OF STEEPER LAPSE RATES BEHIND THIS INITIAL GRADIENT...AND
WITHIN AXIS OF MID LEVEL MOISTURE ADVECTION AND TAIL OF PV ADVECTION
JUST A FEW SHOWERS AND THUNDERSTORMS. THIS BAND WILL LIKELY NEVER
HAVE MUCH FOR COVERAGE...AND WILL LIMP EASTWARD THROUGH THE REST OF
THE NIGHT AND MORNING HOURS. HARD TO JUSTIFY MUCH MORE THAN A LOW
CHANCE/SCATTERED LEVEL POP THROUGH THE FIRST HALF OF THE DAY...AS
WILL SOON LOSE SUPPORT OF WEAK PV ADVECTION...AND THERE WILL BE A
FAIRLY SUBSTANTIAL WAIT FOR THE MAIN UPPER ENERGY SEEN PUSHING INTO
SOUTHWESTERN WYOMING AND COLORADO ON EARLY MORNING WATER VAPOR
IMAGERY.

AS PRESSURE FALL IN RESPONSE TO BETTER UPPER JET TO THE SOUTH...AS
WELL AS THE SLOWER PROGRESSION... WILL PROBABLY GET A BIT BETTER
BACKING TO LOW LEVEL WINDS AHEAD OF BOUNDARY ACROSS THE LOWER
MISSOURI VALLEY INTO PARTS OF NW IA BY LATE DAY COMPARED TO
LOCATIONS FURTHER NORTHWARD. BOTH THE DEEP LAYER SHEAR AND THE 0-1KM
SHEAR APPEAR AS IF THEY COULD END UP BETTER THAN OPERATIONAL MODELS
INDICATE...ESPECIALLY IF PRE FRONTAL TROUGH ENDS UP A BIT LESS SHARP
ACROSS SOUTHWEST MINNESOTA AND NORTHWEST IOWA. ANOTHER FACTOR TOWARD
SEVERE INTENSITY TODAY IS THE POTENTIAL DESTABILIZATION. AT THIS
TIME...DOES NOT APPEAR AS IF THERE WILL BE A GREAT DEAL OF
DISTURBANCE TO WARMING BY EARLY DAY CONVECTION...OTHER THAN HAVING
AXIS OF MID AND HIGH CLOUDS WITH A MORE SPOTTY COVERAGE TO
PRECIPITATION TO WORK PAST THROUGH MIDDAY. SEEMS AS IF THERE SHOULD
BE A WINDOW TO BOTH GET A LITTLE DIABATIC HEATING...AS WELL AS A
GRADUAL RETURN OF DEEPER MOISTURE AHEAD OF ADVANCING COLD FRONTAL
BOUNDARY. ONE THING TO WATCH IS GROWING AREA OF CONVECTION TO THE
SOUTH ACROSS NORTHERN KS...WHICH MAY SPREAD VERY CLOSE TO THE
SOUTHEASTERN CWA TOWARD MIDDAY.

HOWEVER...AS MAIN PV ADVECTION INCREASES VERY LATE THIS AFTERNOON...
EXPECT THE POTENTIAL SEVERE ACTIVITY TO FINALLY START TO DEVELOP AND
INCREASE RAPIDLY IN COVERAGE AFTER 22Z...WITH MAIN INITIATION CLOSER
TO ENHANCED CONVERGENCE NEAR THE LOWER MISSOURI VALLEY.
INITIALLY... SHEAR VECTORS WOULD SUGGEST DISCRETE DEVELOPMENT...IN
AN ENVIRONMENT WITH PERHAPS 1500-2000 J/KG MLCAPE. ALL MODES OF
SEVERE THREAT WOULD BE IN PLAY...INCLUDING ISOLATED TORNADOES AND
LARGER SIZE HAIL ACROSS NORTHWEST IOWA AND ADJACENT LOCATIONS VERY
LATE AFTERNOON AND EARLY EVENING. THE STRONG LINEAR FORCING ALONG
THE FRONT...AND GRADUAL SHIFT IN SHEAR COMPONENT AWAY FROM CROSS
GRADIENT SHOULD SPELL A CHANGE TOWARD LINEAR STRUCTURES WHICH WILL
FAVOR MORE IN THE WAY OF WIND. OVERALL...LOOKING AT THE MOST
SIGNIFICANT THREAT FOR SEVERE...INCLUDING TORNADOES...ACROSS
NORTHWEST IOWA...EASTERN PORTIONS OF SW MN...AND EXTREME NORTHEAST
NEBRASKA...WITH LESSER SEVERE TYPES BACK ACROSS FAR EASTERN SOUTH
DAKOTA AND INTO ADJACENT SW MN. RAINFALL RATES ARE A CONCERN FOR
POTENTIAL FLASH FLOODING... ESPECIALLY FOR URBAN AREAS...AND THOSE
LOCATIONS OF IDA/WOODBURY COUNTY WHICH RECEIVED VERY HEAVY
RAINFALL THE LAST COUPLE OF DAYS.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 435 AM CDT SUN AUG 31 2014

LABOR DAY HOLIDAY SHOULD BY DRY AND COOLER WITH COLD FRONT AND
ASSOCIATED PRECIP EXPECTED TO EXIT OUR FAR SOUTHEAST EARLY IN THE
DAY. WEAK UPPER WAVE COULD BRING SPOTTY SHOWERS AND STORMS TO
WESTERN PORTIONS OF THE AREA LATE IN THE DAY...BUT BETTER CHANCE
LOOKS TO HOLD OFF UNTIL AFTER SUNSET...THOUGH EVEN THIS EXPECTED TO
BE SCATTERED AT BEST WITH MOISTURE/LIFT MAINLY FOCUSED ABOVE 750MB.
HIGHS FOR THE HOLIDAY SHOULD ONLY BE IN THE MID TO UPPER 70S BEHIND
THE EXITING COLD FRONT...WITH TEMPERATURES MONDAY NIGHT COOLING INTO
THE 50S WITH LIGHT WINDS AND CLEARING SKIES LATE AS THE WAVE SHIFTS
EAST. SUNSHINE AND SLIGHTLY WARMER TUESDAY...WITH STRONGER PUSH OF
WARM AIR MOVING THROUGH TUESDAY NIGHT AND WEDNESDAY. CANNOT RULE OUT
SPOTTY PRECIP DEVELOPMENT WITH THE WARM ADVECTION TUESDAY NIGHT...
BUT FORECAST SOUNDINGS LACKING MOISTURE AND WILL LEAVE DRY FOR NOW.
MARGINALLY BETTER PRECIP CHANCE IN OUR NORTHEAST WEDNESDAY NIGHT AS
STRONGER LOW LEVEL JET DEVELOPS ACROSS THE PLAINS...BUT AREAS TO OUR
NORTHEAST APPEAR TO BE MORE FAVORED AREA AT THIS TIME.

ANOTHER STRONGER WAVE AND COOL FRONT EXPECTED TO PUSH THROUGH THE
REGION LATE IN THE WORK WEEK...WITH PRECIP CHANCES RAMPING UP
THURSDAY NIGHT AND FRIDAY. TIMING DIFFERS AMONG THE MODELS...WITH
ECMWF/GEM MOVING THE FRONT AND ASSOCIATED PRECIP SOUTH OF OUR AREA
MORE QUICKLY THAN GFS. WILL HANG ONTO LOW CHANCES...MAINLY SOUTH...
INTO FRIDAY NIGHT TO ACCOUNT FOR SLOWER GFS. LATE WEEK TEMPERATURES
SHOULD STILL BE FAIRLY MILD...WITH HIGHS IN THE UPPER 70S AND 80S
THURSDAY. FASTER ECMWF/GEM ALSO HAVE A STRONGER COLD PUSH...AND IF
THEY DO VERIFY...HIGHS FRIDAY/SATURDAY COULD STRUGGLE TO REACH 70.
HOWEVER GIVEN UNCERTAINTY IN TIMING AT THIS RANGE...WILL STICK CLOSE
TO MODEL CONSENSUS IN THE LOWER TO MID 70S FOR NOW.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1238 PM CDT SUN AUG 31 2014
CONVECTION IS THE PRIMARY AVIATION CONCERN FOR THE 18Z TAF
ISSUANCE. MODEL TRENDS HAVE BEEN TO ACCELERATE THE FRONT
SLIGHTLY...SO HAVE SHIFTED THE FOCUS FOR DEEP COMVECTION LATE THIS
AFTERNOON TO MAINLY NORTHWEST IOWA ALONG AND AHEAD OF A COLD
FRONT PUSHING THROUGH THE REGION. THESE STORMS WILL BE CAPABLE OF
PRODUCING LARGE HAIL...DAMAGING WINDS AND AN ISOLATED TORNADO OR
TWO. SIOUX CITY APPEARS TO BE ON THE WESTERN EDGE OF THE MAIN
THREAT AREA.

THERE REMAINS AN OUTSIDE POTENTIAL OF MVFR CEILING/VISIBILITY
THREAT WORKING SOUTHWARD BEHIND MAIN UPPER TROUGH AFTER 06Z INTO
KHON AND AFTER 09Z AT KFSD...BUT HAVE LEFT CLEAR AS APPEARS LOW
PROBABILITY FOR NOW.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHAPMAN
LONG TERM...JH
AVIATION...





000
FXUS63 KFSD 311745
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1245 PM CDT SUN AUG 31 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM CDT SUN AUG 31 2014

GREATEST CONCERN TODAY IS WITH THE SEVERE WEATHER POTENTIAL LATER
TODAY.

LEADING UPPER WAVE LIFTING THROUGH THE NORTHERN PLAINS AT PRESENT.
ENERGY WITH SYSTEM IS PULLING MOSTLY TOWARD NORTH DAKOTA...AND AS AS
RESULT HAVE SEEN EARLIER STRONGER ACTIVITY ACROSS WESTERN SOUTH
DAKOTA REALLY WEAKEN HEADING INTO SOUTHEAST SOUTH DAKOTA. STRONG LOW
LEVEL JET EXHIBITING MUCH BETTER CONVERGENCE TO THE NORTH...AND ON
VEERING NOSE ARE STARTING TO SEE EXTENSION OF MID CLOUDS SOUTHWARD
ACROSS SW MN AND NW IA...WHICH VERY WELL COULD NOT HAVE A CHANCE TO
ACTIVATE TO A BETTER CONVECTIVE BAND BEFORE EXITING THE FSD CWA...
PER SEVERAL RECENT HIGH RESOLUTION MODEL RUNS. WHAT REMAINS IN THE
AREA OF STEEPER LAPSE RATES BEHIND THIS INITIAL GRADIENT...AND
WITHIN AXIS OF MID LEVEL MOISTURE ADVECTION AND TAIL OF PV ADVECTION
JUST A FEW SHOWERS AND THUNDERSTORMS. THIS BAND WILL LIKELY NEVER
HAVE MUCH FOR COVERAGE...AND WILL LIMP EASTWARD THROUGH THE REST OF
THE NIGHT AND MORNING HOURS. HARD TO JUSTIFY MUCH MORE THAN A LOW
CHANCE/SCATTERED LEVEL POP THROUGH THE FIRST HALF OF THE DAY...AS
WILL SOON LOSE SUPPORT OF WEAK PV ADVECTION...AND THERE WILL BE A
FAIRLY SUBSTANTIAL WAIT FOR THE MAIN UPPER ENERGY SEEN PUSHING INTO
SOUTHWESTERN WYOMING AND COLORADO ON EARLY MORNING WATER VAPOR
IMAGERY.

AS PRESSURE FALL IN RESPONSE TO BETTER UPPER JET TO THE SOUTH...AS
WELL AS THE SLOWER PROGRESSION... WILL PROBABLY GET A BIT BETTER
BACKING TO LOW LEVEL WINDS AHEAD OF BOUNDARY ACROSS THE LOWER
MISSOURI VALLEY INTO PARTS OF NW IA BY LATE DAY COMPARED TO
LOCATIONS FURTHER NORTHWARD. BOTH THE DEEP LAYER SHEAR AND THE 0-1KM
SHEAR APPEAR AS IF THEY COULD END UP BETTER THAN OPERATIONAL MODELS
INDICATE...ESPECIALLY IF PRE FRONTAL TROUGH ENDS UP A BIT LESS SHARP
ACROSS SOUTHWEST MINNESOTA AND NORTHWEST IOWA. ANOTHER FACTOR TOWARD
SEVERE INTENSITY TODAY IS THE POTENTIAL DESTABILIZATION. AT THIS
TIME...DOES NOT APPEAR AS IF THERE WILL BE A GREAT DEAL OF
DISTURBANCE TO WARMING BY EARLY DAY CONVECTION...OTHER THAN HAVING
AXIS OF MID AND HIGH CLOUDS WITH A MORE SPOTTY COVERAGE TO
PRECIPITATION TO WORK PAST THROUGH MIDDAY. SEEMS AS IF THERE SHOULD
BE A WINDOW TO BOTH GET A LITTLE DIABATIC HEATING...AS WELL AS A
GRADUAL RETURN OF DEEPER MOISTURE AHEAD OF ADVANCING COLD FRONTAL
BOUNDARY. ONE THING TO WATCH IS GROWING AREA OF CONVECTION TO THE
SOUTH ACROSS NORTHERN KS...WHICH MAY SPREAD VERY CLOSE TO THE
SOUTHEASTERN CWA TOWARD MIDDAY.

HOWEVER...AS MAIN PV ADVECTION INCREASES VERY LATE THIS AFTERNOON...
EXPECT THE POTENTIAL SEVERE ACTIVITY TO FINALLY START TO DEVELOP AND
INCREASE RAPIDLY IN COVERAGE AFTER 22Z...WITH MAIN INITIATION CLOSER
TO ENHANCED CONVERGENCE NEAR THE LOWER MISSOURI VALLEY.
INITIALLY... SHEAR VECTORS WOULD SUGGEST DISCRETE DEVELOPMENT...IN
AN ENVIRONMENT WITH PERHAPS 1500-2000 J/KG MLCAPE. ALL MODES OF
SEVERE THREAT WOULD BE IN PLAY...INCLUDING ISOLATED TORNADOES AND
LARGER SIZE HAIL ACROSS NORTHWEST IOWA AND ADJACENT LOCATIONS VERY
LATE AFTERNOON AND EARLY EVENING. THE STRONG LINEAR FORCING ALONG
THE FRONT...AND GRADUAL SHIFT IN SHEAR COMPONENT AWAY FROM CROSS
GRADIENT SHOULD SPELL A CHANGE TOWARD LINEAR STRUCTURES WHICH WILL
FAVOR MORE IN THE WAY OF WIND. OVERALL...LOOKING AT THE MOST
SIGNIFICANT THREAT FOR SEVERE...INCLUDING TORNADOES...ACROSS
NORTHWEST IOWA...EASTERN PORTIONS OF SW MN...AND EXTREME NORTHEAST
NEBRASKA...WITH LESSER SEVERE TYPES BACK ACROSS FAR EASTERN SOUTH
DAKOTA AND INTO ADJACENT SW MN. RAINFALL RATES ARE A CONCERN FOR
POTENTIAL FLASH FLOODING... ESPECIALLY FOR URBAN AREAS...AND THOSE
LOCATIONS OF IDA/WOODBURY COUNTY WHICH RECEIVED VERY HEAVY
RAINFALL THE LAST COUPLE OF DAYS.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 435 AM CDT SUN AUG 31 2014

LABOR DAY HOLIDAY SHOULD BY DRY AND COOLER WITH COLD FRONT AND
ASSOCIATED PRECIP EXPECTED TO EXIT OUR FAR SOUTHEAST EARLY IN THE
DAY. WEAK UPPER WAVE COULD BRING SPOTTY SHOWERS AND STORMS TO
WESTERN PORTIONS OF THE AREA LATE IN THE DAY...BUT BETTER CHANCE
LOOKS TO HOLD OFF UNTIL AFTER SUNSET...THOUGH EVEN THIS EXPECTED TO
BE SCATTERED AT BEST WITH MOISTURE/LIFT MAINLY FOCUSED ABOVE 750MB.
HIGHS FOR THE HOLIDAY SHOULD ONLY BE IN THE MID TO UPPER 70S BEHIND
THE EXITING COLD FRONT...WITH TEMPERATURES MONDAY NIGHT COOLING INTO
THE 50S WITH LIGHT WINDS AND CLEARING SKIES LATE AS THE WAVE SHIFTS
EAST. SUNSHINE AND SLIGHTLY WARMER TUESDAY...WITH STRONGER PUSH OF
WARM AIR MOVING THROUGH TUESDAY NIGHT AND WEDNESDAY. CANNOT RULE OUT
SPOTTY PRECIP DEVELOPMENT WITH THE WARM ADVECTION TUESDAY NIGHT...
BUT FORECAST SOUNDINGS LACKING MOISTURE AND WILL LEAVE DRY FOR NOW.
MARGINALLY BETTER PRECIP CHANCE IN OUR NORTHEAST WEDNESDAY NIGHT AS
STRONGER LOW LEVEL JET DEVELOPS ACROSS THE PLAINS...BUT AREAS TO OUR
NORTHEAST APPEAR TO BE MORE FAVORED AREA AT THIS TIME.

ANOTHER STRONGER WAVE AND COOL FRONT EXPECTED TO PUSH THROUGH THE
REGION LATE IN THE WORK WEEK...WITH PRECIP CHANCES RAMPING UP
THURSDAY NIGHT AND FRIDAY. TIMING DIFFERS AMONG THE MODELS...WITH
ECMWF/GEM MOVING THE FRONT AND ASSOCIATED PRECIP SOUTH OF OUR AREA
MORE QUICKLY THAN GFS. WILL HANG ONTO LOW CHANCES...MAINLY SOUTH...
INTO FRIDAY NIGHT TO ACCOUNT FOR SLOWER GFS. LATE WEEK TEMPERATURES
SHOULD STILL BE FAIRLY MILD...WITH HIGHS IN THE UPPER 70S AND 80S
THURSDAY. FASTER ECMWF/GEM ALSO HAVE A STRONGER COLD PUSH...AND IF
THEY DO VERIFY...HIGHS FRIDAY/SATURDAY COULD STRUGGLE TO REACH 70.
HOWEVER GIVEN UNCERTAINTY IN TIMING AT THIS RANGE...WILL STICK CLOSE
TO MODEL CONSENSUS IN THE LOWER TO MID 70S FOR NOW.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1238 PM CDT SUN AUG 31 2014
CONVECTION IS THE PRIMARY AVIATION CONCERN FOR THE 18Z TAF
ISSUANCE. MODEL TRENDS HAVE BEEN TO ACCELERATE THE FRONT
SLIGHTLY...SO HAVE SHIFTED THE FOCUS FOR DEEP COMVECTION LATE THIS
AFTERNOON TO MAINLY NORTHWEST IOWA ALONG AND AHEAD OF A COLD
FRONT PUSHING THROUGH THE REGION. THESE STORMS WILL BE CAPABLE OF
PRODUCING LARGE HAIL...DAMAGING WINDS AND AN ISOLATED TORNADO OR
TWO. SIOUX CITY APPEARS TO BE ON THE WESTERN EDGE OF THE MAIN
THREAT AREA.

THERE REMAINS AN OUTSIDE POTENTIAL OF MVFR CEILING/VISIBILITY
THREAT WORKING SOUTHWARD BEHIND MAIN UPPER TROUGH AFTER 06Z INTO
KHON AND AFTER 09Z AT KFSD...BUT HAVE LEFT CLEAR AS APPEARS LOW
PROBABILITY FOR NOW.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHAPMAN
LONG TERM...JH
AVIATION...




000
FXUS63 KFSD 311155
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
655 AM CDT SUN AUG 31 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM CDT SUN AUG 31 2014

GREATEST CONCERN TODAY IS WITH THE SEVERE WEATHER POTENTIAL LATER
TODAY.

LEADING UPPER WAVE LIFTING THROUGH THE NORTHERN PLAINS AT PRESENT.
ENERGY WITH SYSTEM IS PULLING MOSTLY TOWARD NORTH DAKOTA...AND AS AS
RESULT HAVE SEEN EARLIER STRONGER ACTIVITY ACROSS WESTERN SOUTH
DAKOTA REALLY WEAKEN HEADING INTO SOUTHEAST SOUTH DAKOTA. STRONG LOW
LEVEL JET EXHIBITING MUCH BETTER CONVERGENCE TO THE NORTH...AND ON
VEERING NOSE ARE STARTING TO SEE EXTENSION OF MID CLOUDS SOUTHWARD
ACROSS SW MN AND NW IA...WHICH VERY WELL COULD NOT HAVE A CHANCE TO
ACTIVATE TO A BETTER CONVECTIVE BAND BEFORE EXITING THE FSD CWA...
PER SEVERAL RECENT HIGH RESOLUTION MODEL RUNS. WHAT REMAINS IN THE
AREA OF STEEPER LAPSE RATES BEHIND THIS INITIAL GRADIENT...AND
WITHIN AXIS OF MID LEVEL MOISTURE ADVECTION AND TAIL OF PV ADVECTION
JUST A FEW SHOWERS AND THUNDERSTORMS. THIS BAND WILL LIKELY NEVER
HAVE MUCH FOR COVERAGE...AND WILL LIMP EASTWARD THROUGH THE REST OF
THE NIGHT AND MORNING HOURS. HARD TO JUSTIFY MUCH MORE THAN A LOW
CHANCE/SCATTERED LEVEL POP THROUGH THE FIRST HALF OF THE DAY...AS
WILL SOON LOSE SUPPORT OF WEAK PV ADVECTION...AND THERE WILL BE A
FAIRLY SUBSTANTIAL WAIT FOR THE MAIN UPPER ENERGY SEEN PUSHING INTO
SOUTHWESTERN WYOMING AND COLORADO ON EARLY MORNING WATER VAPOR
IMAGERY.

AS PRESSURE FALL IN RESPONSE TO BETTER UPPER JET TO THE SOUTH...AS
WELL AS THE SLOWER PROGRESSION... WILL PROBABLY GET A BIT BETTER
BACKING TO LOW LEVEL WINDS AHEAD OF BOUNDARY ACROSS THE LOWER
MISSOURI VALLEY INTO PARTS OF NW IA BY LATE DAY COMPARED TO
LOCATIONS FURTHER NORTHWARD. BOTH THE DEEP LAYER SHEAR AND THE 0-1KM
SHEAR APPEAR AS IF THEY COULD END UP BETTER THAN OPERATIONAL MODELS
INDICATE...ESPECIALLY IF PRE FRONTAL TROUGH ENDS UP A BIT LESS SHARP
ACROSS SOUTHWEST MINNESOTA AND NORTHWEST IOWA. ANOTHER FACTOR TOWARD
SEVERE INTENSITY TODAY IS THE POTENTIAL DESTABILIZATION. AT THIS
TIME...DOES NOT APPEAR AS IF THERE WILL BE A GREAT DEAL OF
DISTURBANCE TO WARMING BY EARLY DAY CONVECTION...OTHER THAN HAVING
AXIS OF MID AND HIGH CLOUDS WITH A MORE SPOTTY COVERAGE TO
PRECIPITATION TO WORK PAST THROUGH MIDDAY. SEEMS AS IF THERE SHOULD
BE A WINDOW TO BOTH GET A LITTLE DIABATIC HEATING...AS WELL AS A
GRADUAL RETURN OF DEEPER MOISTURE AHEAD OF ADVANCING COLD FRONTAL
BOUNDARY. ONE THING TO WATCH IS GROWING AREA OF CONVECTION TO THE
SOUTH ACROSS NORTHERN KS...WHICH MAY SPREAD VERY CLOSE TO THE
SOUTHEASTERN CWA TOWARD MIDDAY.

HOWEVER...AS MAIN PV ADVECTION INCREASES VERY LATE THIS AFTERNOON...
EXPECT THE POTENTIAL SEVERE ACTIVITY TO FINALLY START TO DEVELOP AND
INCREASE RAPIDLY IN COVERAGE AFTER 22Z...WITH MAIN INITIATION CLOSER
TO ENHANCED CONVERGENCE NEAR THE LOWER MISSOURI VALLEY.
INITIALLY... SHEAR VECTORS WOULD SUGGEST DISCRETE DEVELOPMENT...IN
AN ENVIRONMENT WITH PERHAPS 1500-2000 J/KG MLCAPE. ALL MODES OF
SEVERE THREAT WOULD BE IN PLAY...INCLUDING ISOLATED TORNADOES AND
LARGER SIZE HAIL ACROSS NORTHWEST IOWA AND ADJACENT LOCATIONS VERY
LATE AFTERNOON AND EARLY EVENING. THE STRONG LINEAR FORCING ALONG
THE FRONT...AND GRADUAL SHIFT IN SHEAR COMPONENT AWAY FROM CROSS
GRADIENT SHOULD SPELL A CHANGE TOWARD LINEAR STRUCTURES WHICH WILL
FAVOR MORE IN THE WAY OF WIND. OVERALL...LOOKING AT THE MOST
SIGNIFICANT THREAT FOR SEVERE...INCLUDING TORNADOES...ACROSS
NORTHWEST IOWA...EASTERN PORTIONS OF SW MN...AND EXTREME NORTHEAST
NEBRASKA...WITH LESSER SEVERE TYPES BACK ACROSS FAR EASTERN SOUTH
DAKOTA AND INTO ADJACENT SW MN. RAINFALL RATES ARE A CONCERN FOR
POTENTIAL FLASH FLOODING... ESPECIALLY FOR URBAN AREAS...AND THOSE
LOCATIONS OF IDA/WOODBURY COUNTY WHICH RECEIVED VERY HEAVY
RAINFALL THE LAST COUPLE OF DAYS.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 435 AM CDT SUN AUG 31 2014

LABOR DAY HOLIDAY SHOULD BY DRY AND COOLER WITH COLD FRONT AND
ASSOCIATED PRECIP EXPECTED TO EXIT OUR FAR SOUTHEAST EARLY IN THE
DAY. WEAK UPPER WAVE COULD BRING SPOTTY SHOWERS AND STORMS TO
WESTERN PORTIONS OF THE AREA LATE IN THE DAY...BUT BETTER CHANCE
LOOKS TO HOLD OFF UNTIL AFTER SUNSET...THOUGH EVEN THIS EXPECTED TO
BE SCATTERED AT BEST WITH MOISTURE/LIFT MAINLY FOCUSED ABOVE 750MB.
HIGHS FOR THE HOLIDAY SHOULD ONLY BE IN THE MID TO UPPER 70S BEHIND
THE EXITING COLD FRONT...WITH TEMPERATURES MONDAY NIGHT COOLING INTO
THE 50S WITH LIGHT WINDS AND CLEARING SKIES LATE AS THE WAVE SHIFTS
EAST. SUNSHINE AND SLIGHTLY WARMER TUESDAY...WITH STRONGER PUSH OF
WARM AIR MOVING THROUGH TUESDAY NIGHT AND WEDNESDAY. CANNOT RULE OUT
SPOTTY PRECIP DEVELOPMENT WITH THE WARM ADVECTION TUESDAY NIGHT...
BUT FORECAST SOUNDINGS LACKING MOISTURE AND WILL LEAVE DRY FOR NOW.
MARGINALLY BETTER PRECIP CHANCE IN OUR NORTHEAST WEDNESDAY NIGHT AS
STRONGER LOW LEVEL JET DEVELOPS ACROSS THE PLAINS...BUT AREAS TO OUR
NORTHEAST APPEAR TO BE MORE FAVORED AREA AT THIS TIME.

ANOTHER STRONGER WAVE AND COOL FRONT EXPECTED TO PUSH THROUGH THE
REGION LATE IN THE WORK WEEK...WITH PRECIP CHANCES RAMPING UP
THURSDAY NIGHT AND FRIDAY. TIMING DIFFERS AMONG THE MODELS...WITH
ECMWF/GEM MOVING THE FRONT AND ASSOCIATED PRECIP SOUTH OF OUR AREA
MORE QUICKLY THAN GFS. WILL HANG ONTO LOW CHANCES...MAINLY SOUTH...
INTO FRIDAY NIGHT TO ACCOUNT FOR SLOWER GFS. LATE WEEK TEMPERATURES
SHOULD STILL BE FAIRLY MILD...WITH HIGHS IN THE UPPER 70S AND 80S
THURSDAY. FASTER ECMWF/GEM ALSO HAVE A STRONGER COLD PUSH...AND IF
THEY DO VERIFY...HIGHS FRIDAY/SATURDAY COULD STRUGGLE TO REACH 70.
HOWEVER GIVEN UNCERTAINTY IN TIMING AT THIS RANGE...WILL STICK CLOSE
TO MODEL CONSENSUS IN THE LOWER TO MID 70S FOR NOW.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 655 AM CDT SUN AUG 31 2014

CONVECTION IS THE PRIMARY AVIATION CONCERN FOR THE 12Z TAF
ISSUANCE. HIGH BASED SHOWERS AND THUNDERSTORMS WILL PUSH ACROSS
AREAS MAINLY ALONG AND EAST OF INTERSTATE 29 THIS MORNING.
MORE SIGNIFICANT STORMS ARE EXPECTED TO DEVELOP BY MID TO LATE
AFTERNOON ALONG AND AHEAD OF A COLD FRONT PUSHING THROUGH THE
REGION. AREAS MAINLY ACROSS NORTHWEST IOWA AND ADJACENT AREAS OF
SWRN MN...EXTREME SERN SD...AND NERN NEBRASKA...WILL HAVE THE
GREATEST THREAT OF SEVERE STORMS CAPABLE OF LARGE HAIL...DAMAGING
WINDS... AND A FEW TORNADOES. STRONG STORMS AROUND KSUX WILL
LIKELY CONTAIN BRIEF IFR VISIBILITIES AND MVFR CEILINGS.

THERE COULD BE A LITTLE MVFR CEILING/VISIBILITY THREAT WORKING
SOUTHWARD BEHIND MAIN UPPER TROUGH AFTER 06Z INTO KHON AND AFTER
09Z AT KFSD...BUT HAVE LEFT CLEAR AS APPEARS LOW PROBABILITY FOR
NOW.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHAPMAN
LONG TERM...JH
AVIATION...CHAPMAN





000
FXUS63 KFSD 311155
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
655 AM CDT SUN AUG 31 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM CDT SUN AUG 31 2014

GREATEST CONCERN TODAY IS WITH THE SEVERE WEATHER POTENTIAL LATER
TODAY.

LEADING UPPER WAVE LIFTING THROUGH THE NORTHERN PLAINS AT PRESENT.
ENERGY WITH SYSTEM IS PULLING MOSTLY TOWARD NORTH DAKOTA...AND AS AS
RESULT HAVE SEEN EARLIER STRONGER ACTIVITY ACROSS WESTERN SOUTH
DAKOTA REALLY WEAKEN HEADING INTO SOUTHEAST SOUTH DAKOTA. STRONG LOW
LEVEL JET EXHIBITING MUCH BETTER CONVERGENCE TO THE NORTH...AND ON
VEERING NOSE ARE STARTING TO SEE EXTENSION OF MID CLOUDS SOUTHWARD
ACROSS SW MN AND NW IA...WHICH VERY WELL COULD NOT HAVE A CHANCE TO
ACTIVATE TO A BETTER CONVECTIVE BAND BEFORE EXITING THE FSD CWA...
PER SEVERAL RECENT HIGH RESOLUTION MODEL RUNS. WHAT REMAINS IN THE
AREA OF STEEPER LAPSE RATES BEHIND THIS INITIAL GRADIENT...AND
WITHIN AXIS OF MID LEVEL MOISTURE ADVECTION AND TAIL OF PV ADVECTION
JUST A FEW SHOWERS AND THUNDERSTORMS. THIS BAND WILL LIKELY NEVER
HAVE MUCH FOR COVERAGE...AND WILL LIMP EASTWARD THROUGH THE REST OF
THE NIGHT AND MORNING HOURS. HARD TO JUSTIFY MUCH MORE THAN A LOW
CHANCE/SCATTERED LEVEL POP THROUGH THE FIRST HALF OF THE DAY...AS
WILL SOON LOSE SUPPORT OF WEAK PV ADVECTION...AND THERE WILL BE A
FAIRLY SUBSTANTIAL WAIT FOR THE MAIN UPPER ENERGY SEEN PUSHING INTO
SOUTHWESTERN WYOMING AND COLORADO ON EARLY MORNING WATER VAPOR
IMAGERY.

AS PRESSURE FALL IN RESPONSE TO BETTER UPPER JET TO THE SOUTH...AS
WELL AS THE SLOWER PROGRESSION... WILL PROBABLY GET A BIT BETTER
BACKING TO LOW LEVEL WINDS AHEAD OF BOUNDARY ACROSS THE LOWER
MISSOURI VALLEY INTO PARTS OF NW IA BY LATE DAY COMPARED TO
LOCATIONS FURTHER NORTHWARD. BOTH THE DEEP LAYER SHEAR AND THE 0-1KM
SHEAR APPEAR AS IF THEY COULD END UP BETTER THAN OPERATIONAL MODELS
INDICATE...ESPECIALLY IF PRE FRONTAL TROUGH ENDS UP A BIT LESS SHARP
ACROSS SOUTHWEST MINNESOTA AND NORTHWEST IOWA. ANOTHER FACTOR TOWARD
SEVERE INTENSITY TODAY IS THE POTENTIAL DESTABILIZATION. AT THIS
TIME...DOES NOT APPEAR AS IF THERE WILL BE A GREAT DEAL OF
DISTURBANCE TO WARMING BY EARLY DAY CONVECTION...OTHER THAN HAVING
AXIS OF MID AND HIGH CLOUDS WITH A MORE SPOTTY COVERAGE TO
PRECIPITATION TO WORK PAST THROUGH MIDDAY. SEEMS AS IF THERE SHOULD
BE A WINDOW TO BOTH GET A LITTLE DIABATIC HEATING...AS WELL AS A
GRADUAL RETURN OF DEEPER MOISTURE AHEAD OF ADVANCING COLD FRONTAL
BOUNDARY. ONE THING TO WATCH IS GROWING AREA OF CONVECTION TO THE
SOUTH ACROSS NORTHERN KS...WHICH MAY SPREAD VERY CLOSE TO THE
SOUTHEASTERN CWA TOWARD MIDDAY.

HOWEVER...AS MAIN PV ADVECTION INCREASES VERY LATE THIS AFTERNOON...
EXPECT THE POTENTIAL SEVERE ACTIVITY TO FINALLY START TO DEVELOP AND
INCREASE RAPIDLY IN COVERAGE AFTER 22Z...WITH MAIN INITIATION CLOSER
TO ENHANCED CONVERGENCE NEAR THE LOWER MISSOURI VALLEY.
INITIALLY... SHEAR VECTORS WOULD SUGGEST DISCRETE DEVELOPMENT...IN
AN ENVIRONMENT WITH PERHAPS 1500-2000 J/KG MLCAPE. ALL MODES OF
SEVERE THREAT WOULD BE IN PLAY...INCLUDING ISOLATED TORNADOES AND
LARGER SIZE HAIL ACROSS NORTHWEST IOWA AND ADJACENT LOCATIONS VERY
LATE AFTERNOON AND EARLY EVENING. THE STRONG LINEAR FORCING ALONG
THE FRONT...AND GRADUAL SHIFT IN SHEAR COMPONENT AWAY FROM CROSS
GRADIENT SHOULD SPELL A CHANGE TOWARD LINEAR STRUCTURES WHICH WILL
FAVOR MORE IN THE WAY OF WIND. OVERALL...LOOKING AT THE MOST
SIGNIFICANT THREAT FOR SEVERE...INCLUDING TORNADOES...ACROSS
NORTHWEST IOWA...EASTERN PORTIONS OF SW MN...AND EXTREME NORTHEAST
NEBRASKA...WITH LESSER SEVERE TYPES BACK ACROSS FAR EASTERN SOUTH
DAKOTA AND INTO ADJACENT SW MN. RAINFALL RATES ARE A CONCERN FOR
POTENTIAL FLASH FLOODING... ESPECIALLY FOR URBAN AREAS...AND THOSE
LOCATIONS OF IDA/WOODBURY COUNTY WHICH RECEIVED VERY HEAVY
RAINFALL THE LAST COUPLE OF DAYS.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 435 AM CDT SUN AUG 31 2014

LABOR DAY HOLIDAY SHOULD BY DRY AND COOLER WITH COLD FRONT AND
ASSOCIATED PRECIP EXPECTED TO EXIT OUR FAR SOUTHEAST EARLY IN THE
DAY. WEAK UPPER WAVE COULD BRING SPOTTY SHOWERS AND STORMS TO
WESTERN PORTIONS OF THE AREA LATE IN THE DAY...BUT BETTER CHANCE
LOOKS TO HOLD OFF UNTIL AFTER SUNSET...THOUGH EVEN THIS EXPECTED TO
BE SCATTERED AT BEST WITH MOISTURE/LIFT MAINLY FOCUSED ABOVE 750MB.
HIGHS FOR THE HOLIDAY SHOULD ONLY BE IN THE MID TO UPPER 70S BEHIND
THE EXITING COLD FRONT...WITH TEMPERATURES MONDAY NIGHT COOLING INTO
THE 50S WITH LIGHT WINDS AND CLEARING SKIES LATE AS THE WAVE SHIFTS
EAST. SUNSHINE AND SLIGHTLY WARMER TUESDAY...WITH STRONGER PUSH OF
WARM AIR MOVING THROUGH TUESDAY NIGHT AND WEDNESDAY. CANNOT RULE OUT
SPOTTY PRECIP DEVELOPMENT WITH THE WARM ADVECTION TUESDAY NIGHT...
BUT FORECAST SOUNDINGS LACKING MOISTURE AND WILL LEAVE DRY FOR NOW.
MARGINALLY BETTER PRECIP CHANCE IN OUR NORTHEAST WEDNESDAY NIGHT AS
STRONGER LOW LEVEL JET DEVELOPS ACROSS THE PLAINS...BUT AREAS TO OUR
NORTHEAST APPEAR TO BE MORE FAVORED AREA AT THIS TIME.

ANOTHER STRONGER WAVE AND COOL FRONT EXPECTED TO PUSH THROUGH THE
REGION LATE IN THE WORK WEEK...WITH PRECIP CHANCES RAMPING UP
THURSDAY NIGHT AND FRIDAY. TIMING DIFFERS AMONG THE MODELS...WITH
ECMWF/GEM MOVING THE FRONT AND ASSOCIATED PRECIP SOUTH OF OUR AREA
MORE QUICKLY THAN GFS. WILL HANG ONTO LOW CHANCES...MAINLY SOUTH...
INTO FRIDAY NIGHT TO ACCOUNT FOR SLOWER GFS. LATE WEEK TEMPERATURES
SHOULD STILL BE FAIRLY MILD...WITH HIGHS IN THE UPPER 70S AND 80S
THURSDAY. FASTER ECMWF/GEM ALSO HAVE A STRONGER COLD PUSH...AND IF
THEY DO VERIFY...HIGHS FRIDAY/SATURDAY COULD STRUGGLE TO REACH 70.
HOWEVER GIVEN UNCERTAINTY IN TIMING AT THIS RANGE...WILL STICK CLOSE
TO MODEL CONSENSUS IN THE LOWER TO MID 70S FOR NOW.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 655 AM CDT SUN AUG 31 2014

CONVECTION IS THE PRIMARY AVIATION CONCERN FOR THE 12Z TAF
ISSUANCE. HIGH BASED SHOWERS AND THUNDERSTORMS WILL PUSH ACROSS
AREAS MAINLY ALONG AND EAST OF INTERSTATE 29 THIS MORNING.
MORE SIGNIFICANT STORMS ARE EXPECTED TO DEVELOP BY MID TO LATE
AFTERNOON ALONG AND AHEAD OF A COLD FRONT PUSHING THROUGH THE
REGION. AREAS MAINLY ACROSS NORTHWEST IOWA AND ADJACENT AREAS OF
SWRN MN...EXTREME SERN SD...AND NERN NEBRASKA...WILL HAVE THE
GREATEST THREAT OF SEVERE STORMS CAPABLE OF LARGE HAIL...DAMAGING
WINDS... AND A FEW TORNADOES. STRONG STORMS AROUND KSUX WILL
LIKELY CONTAIN BRIEF IFR VISIBILITIES AND MVFR CEILINGS.

THERE COULD BE A LITTLE MVFR CEILING/VISIBILITY THREAT WORKING
SOUTHWARD BEHIND MAIN UPPER TROUGH AFTER 06Z INTO KHON AND AFTER
09Z AT KFSD...BUT HAVE LEFT CLEAR AS APPEARS LOW PROBABILITY FOR
NOW.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHAPMAN
LONG TERM...JH
AVIATION...CHAPMAN




000
FXUS63 KFSD 310935
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
435 AM CDT SUN AUG 31 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM CDT SUN AUG 31 2014

GREATEST CONCERN TODAY IS WITH THE SEVERE WEATHER POTENTIAL LATER
TODAY.

LEADING UPPER WAVE LIFTING THROUGH THE NORTHERN PLAINS AT PRESENT.
ENERGY WITH SYSTEM IS PULLING MOSTLY TOWARD NORTH DAKOTA...AND AS AS
RESULT HAVE SEEN EARLIER STRONGER ACTIVITY ACROSS WESTERN SOUTH
DAKOTA REALLY WEAKEN HEADING INTO SOUTHEAST SOUTH DAKOTA. STRONG LOW
LEVEL JET EXHIBITING MUCH BETTER CONVERGENCE TO THE NORTH...AND ON
VEERING NOSE ARE STARTING TO SEE EXTENSION OF MID CLOUDS SOUTHWARD
ACROSS SW MN AND NW IA...WHICH VERY WELL COULD NOT HAVE A CHANCE TO
ACTIVATE TO A BETTER CONVECTIVE BAND BEFORE EXITING THE FSD CWA...
PER SEVERAL RECENT HIGH RESOLUTION MODEL RUNS. WHAT REMAINS IN THE
AREA OF STEEPER LAPSE RATES BEHIND THIS INITIAL GRADIENT...AND
WITHIN AXIS OF MID LEVEL MOISTURE ADVECTION AND TAIL OF PV ADVECTION
JUST A FEW SHOWERS AND THUNDERSTORMS. THIS BAND WILL LIKELY NEVER
HAVE MUCH FOR COVERAGE...AND WILL LIMP EASTWARD THROUGH THE REST OF
THE NIGHT AND MORNING HOURS. HARD TO JUSTIFY MUCH MORE THAN A LOW
CHANCE/SCATTERED LEVEL POP THROUGH THE FIRST HALF OF THE DAY...AS
WILL SOON LOSE SUPPORT OF WEAK PV ADVECTION...AND THERE WILL BE A
FAIRLY SUBSTANTIAL WAIT FOR THE MAIN UPPER ENERGY SEEN PUSHING INTO
SOUTHWESTERN WYOMING AND COLORADO ON EARLY MORNING WATER VAPOR
IMAGERY.

AS PRESSURE FALL IN RESPONSE TO BETTER UPPER JET TO THE SOUTH...AS
WELL AS THE SLOWER PROGRESSION... WILL PROBABLY GET A BIT BETTER
BACKING TO LOW LEVEL WINDS AHEAD OF BOUNDARY ACROSS THE LOWER
MISSOURI VALLEY INTO PARTS OF NW IA BY LATE DAY COMPARED TO
LOCATIONS FURTHER NORTHWARD. BOTH THE DEEP LAYER SHEAR AND THE 0-1KM
SHEAR APPEAR AS IF THEY COULD END UP BETTER THAN OPERATIONAL MODELS
INDICATE...ESPECIALLY IF PRE FRONTAL TROUGH ENDS UP A BIT LESS SHARP
ACROSS SOUTHWEST MINNESOTA AND NORTHWEST IOWA. ANOTHER FACTOR TOWARD
SEVERE INTENSITY TODAY IS THE POTENTIAL DESTABILIZATION. AT THIS
TIME...DOES NOT APPEAR AS IF THERE WILL BE A GREAT DEAL OF
DISTURBANCE TO WARMING BY EARLY DAY CONVECTION...OTHER THAN HAVING
AXIS OF MID AND HIGH CLOUDS WITH A MORE SPOTTY COVERAGE TO
PRECIPITATION TO WORK PAST THROUGH MIDDAY. SEEMS AS IF THERE SHOULD
BE A WINDOW TO BOTH GET A LITTLE DIABATIC HEATING...AS WELL AS A
GRADUAL RETURN OF DEEPER MOISTURE AHEAD OF ADVANCING COLD FRONTAL
BOUNDARY. ONE THING TO WATCH IS GROWING AREA OF CONVECTION TO THE
SOUTH ACROSS NORTHERN KS...WHICH MAY SPREAD VERY CLOSE TO THE
SOUTHEASTERN CWA TOWARD MIDDAY.

HOWEVER...AS MAIN PV ADVECTION INCREASES VERY LATE THIS AFTERNOON...
EXPECT THE POTENTIAL SEVERE ACTIVITY TO FINALLY START TO DEVELOP AND
INCREASE RAPIDLY IN COVERAGE AFTER 22Z...WITH MAIN INITIATION CLOSER
TO ENHANCED CONVERGENCE NEAR THE LOWER MISSOURI VALLEY.
INITIALLY... SHEAR VECTORS WOULD SUGGEST DISCRETE DEVELOPMENT...IN
AN ENVIRONMENT WITH PERHAPS 1500-2000 J/KG MLCAPE. ALL MODES OF
SEVERE THREAT WOULD BE IN PLAY...INCLUDING ISOLATED TORNADOES AND
LARGER SIZE HAIL ACROSS NORTHWEST IOWA AND ADJACENT LOCATIONS VERY
LATE AFTERNOON AND EARLY EVENING. THE STRONG LINEAR FORCING ALONG
THE FRONT...AND GRADUAL SHIFT IN SHEAR COMPONENT AWAY FROM CROSS
GRADIENT SHOULD SPELL A CHANGE TOWARD LINEAR STRUCTURES WHICH WILL
FAVOR MORE IN THE WAY OF WIND. OVERALL...LOOKING AT THE MOST
SIGNIFICANT THREAT FOR SEVERE...INCLUDING TORNADOES...ACROSS
NORTHWEST IOWA...EASTERN PORTIONS OF SW MN...AND EXTREME NORTHEAST
NEBRASKA...WITH LESSER SEVERE TYPES BACK ACROSS FAR EASTERN SOUTH
DAKOTA AND INTO ADJACENT SW MN. RAINFALL RATES ARE A CONCERN FOR
POTENTIAL FLASH FLOODING... ESPECIALLY FOR URBAN AREAS...AND THOSE
LOCATIONS OF IDA/WOODBURY COUNTY WHICH RECEIVED VERY HEAVY
RAINFALL THE LAST COUPLE OF DAYS.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 435 AM CDT SUN AUG 31 2014

LABOR DAY HOLIDAY SHOULD BY DRY AND COOLER WITH COLD FRONT AND
ASSOCIATED PRECIP EXPECTED TO EXIT OUR FAR SOUTHEAST EARLY IN THE
DAY. WEAK UPPER WAVE COULD BRING SPOTTY SHOWERS AND STORMS TO
WESTERN PORTIONS OF THE AREA LATE IN THE DAY...BUT BETTER CHANCE
LOOKS TO HOLD OFF UNTIL AFTER SUNSET...THOUGH EVEN THIS EXPECTED TO
BE SCATTERED AT BEST WITH MOISTURE/LIFT MAINLY FOCUSED ABOVE 750MB.
HIGHS FOR THE HOLIDAY SHOULD ONLY BE IN THE MID TO UPPER 70S BEHIND
THE EXITING COLD FRONT...WITH TEMPERATURES MONDAY NIGHT COOLING INTO
THE 50S WITH LIGHT WINDS AND CLEARING SKIES LATE AS THE WAVE SHIFTS
EAST. SUNSHINE AND SLIGHTLY WARMER TUESDAY...WITH STRONGER PUSH OF
WARM AIR MOVING THROUGH TUESDAY NIGHT AND WEDNESDAY. CANNOT RULE OUT
SPOTTY PRECIP DEVELOPMENT WITH THE WARM ADVECTION TUESDAY NIGHT...
BUT FORECAST SOUNDINGS LACKING MOISTURE AND WILL LEAVE DRY FOR NOW.
MARGINALLY BETTER PRECIP CHANCE IN OUR NORTHEAST WEDNESDAY NIGHT AS
STRONGER LOW LEVEL JET DEVELOPS ACROSS THE PLAINS...BUT AREAS TO OUR
NORTHEAST APPEAR TO BE MORE FAVORED AREA AT THIS TIME.

ANOTHER STRONGER WAVE AND COOL FRONT EXPECTED TO PUSH THROUGH THE
REGION LATE IN THE WORK WEEK...WITH PRECIP CHANCES RAMPING UP
THURSDAY NIGHT AND FRIDAY. TIMING DIFFERS AMONG THE MODELS...WITH
ECMWF/GEM MOVING THE FRONT AND ASSOCIATED PRECIP SOUTH OF OUR AREA
MORE QUICKLY THAN GFS. WILL HANG ONTO LOW CHANCES...MAINLY SOUTH...
INTO FRIDAY NIGHT TO ACCOUNT FOR SLOWER GFS. LATE WEEK TEMPERATURES
SHOULD STILL BE FAIRLY MILD...WITH HIGHS IN THE UPPER 70S AND 80S
THURSDAY. FASTER ECMWF/GEM ALSO HAVE A STRONGER COLD PUSH...AND IF
THEY DO VERIFY...HIGHS FRIDAY/SATURDAY COULD STRUGGLE TO REACH 70.
HOWEVER GIVEN UNCERTAINTY IN TIMING AT THIS RANGE...WILL STICK CLOSE
TO MODEL CONSENSUS IN THE LOWER TO MID 70S FOR NOW.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1044 PM CDT SAT AUG 30 2014

CONVECTION OVER CENTRAL SOUTH DAKOTA LOOKS TO BE DIMINISHING AS IT
MOVES EASTWARD...THOUGH ISOLATED STORMS MAY PUSH ACROSS THE AREA
OVERNIGHT. WITH THE ISOLATED NATURE OF THE CONVECTION...DID NOT
INCLUDE IN TAFS. BETTER CHANCES OF STORMS WILL OCCUR FROM NEAR THE
INTERSTATE 29 CORRIDOR AND EASTWARD LATER ON SUNDAY
AFTERNOON...EFFECTING THE KFSD AND KSUX TAF SITES INTO SUNDAY
EVENING.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHAPMAN
LONG TERM...JH
AVIATION...JM




000
FXUS63 KFSD 310935
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
435 AM CDT SUN AUG 31 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM CDT SUN AUG 31 2014

GREATEST CONCERN TODAY IS WITH THE SEVERE WEATHER POTENTIAL LATER
TODAY.

LEADING UPPER WAVE LIFTING THROUGH THE NORTHERN PLAINS AT PRESENT.
ENERGY WITH SYSTEM IS PULLING MOSTLY TOWARD NORTH DAKOTA...AND AS AS
RESULT HAVE SEEN EARLIER STRONGER ACTIVITY ACROSS WESTERN SOUTH
DAKOTA REALLY WEAKEN HEADING INTO SOUTHEAST SOUTH DAKOTA. STRONG LOW
LEVEL JET EXHIBITING MUCH BETTER CONVERGENCE TO THE NORTH...AND ON
VEERING NOSE ARE STARTING TO SEE EXTENSION OF MID CLOUDS SOUTHWARD
ACROSS SW MN AND NW IA...WHICH VERY WELL COULD NOT HAVE A CHANCE TO
ACTIVATE TO A BETTER CONVECTIVE BAND BEFORE EXITING THE FSD CWA...
PER SEVERAL RECENT HIGH RESOLUTION MODEL RUNS. WHAT REMAINS IN THE
AREA OF STEEPER LAPSE RATES BEHIND THIS INITIAL GRADIENT...AND
WITHIN AXIS OF MID LEVEL MOISTURE ADVECTION AND TAIL OF PV ADVECTION
JUST A FEW SHOWERS AND THUNDERSTORMS. THIS BAND WILL LIKELY NEVER
HAVE MUCH FOR COVERAGE...AND WILL LIMP EASTWARD THROUGH THE REST OF
THE NIGHT AND MORNING HOURS. HARD TO JUSTIFY MUCH MORE THAN A LOW
CHANCE/SCATTERED LEVEL POP THROUGH THE FIRST HALF OF THE DAY...AS
WILL SOON LOSE SUPPORT OF WEAK PV ADVECTION...AND THERE WILL BE A
FAIRLY SUBSTANTIAL WAIT FOR THE MAIN UPPER ENERGY SEEN PUSHING INTO
SOUTHWESTERN WYOMING AND COLORADO ON EARLY MORNING WATER VAPOR
IMAGERY.

AS PRESSURE FALL IN RESPONSE TO BETTER UPPER JET TO THE SOUTH...AS
WELL AS THE SLOWER PROGRESSION... WILL PROBABLY GET A BIT BETTER
BACKING TO LOW LEVEL WINDS AHEAD OF BOUNDARY ACROSS THE LOWER
MISSOURI VALLEY INTO PARTS OF NW IA BY LATE DAY COMPARED TO
LOCATIONS FURTHER NORTHWARD. BOTH THE DEEP LAYER SHEAR AND THE 0-1KM
SHEAR APPEAR AS IF THEY COULD END UP BETTER THAN OPERATIONAL MODELS
INDICATE...ESPECIALLY IF PRE FRONTAL TROUGH ENDS UP A BIT LESS SHARP
ACROSS SOUTHWEST MINNESOTA AND NORTHWEST IOWA. ANOTHER FACTOR TOWARD
SEVERE INTENSITY TODAY IS THE POTENTIAL DESTABILIZATION. AT THIS
TIME...DOES NOT APPEAR AS IF THERE WILL BE A GREAT DEAL OF
DISTURBANCE TO WARMING BY EARLY DAY CONVECTION...OTHER THAN HAVING
AXIS OF MID AND HIGH CLOUDS WITH A MORE SPOTTY COVERAGE TO
PRECIPITATION TO WORK PAST THROUGH MIDDAY. SEEMS AS IF THERE SHOULD
BE A WINDOW TO BOTH GET A LITTLE DIABATIC HEATING...AS WELL AS A
GRADUAL RETURN OF DEEPER MOISTURE AHEAD OF ADVANCING COLD FRONTAL
BOUNDARY. ONE THING TO WATCH IS GROWING AREA OF CONVECTION TO THE
SOUTH ACROSS NORTHERN KS...WHICH MAY SPREAD VERY CLOSE TO THE
SOUTHEASTERN CWA TOWARD MIDDAY.

HOWEVER...AS MAIN PV ADVECTION INCREASES VERY LATE THIS AFTERNOON...
EXPECT THE POTENTIAL SEVERE ACTIVITY TO FINALLY START TO DEVELOP AND
INCREASE RAPIDLY IN COVERAGE AFTER 22Z...WITH MAIN INITIATION CLOSER
TO ENHANCED CONVERGENCE NEAR THE LOWER MISSOURI VALLEY.
INITIALLY... SHEAR VECTORS WOULD SUGGEST DISCRETE DEVELOPMENT...IN
AN ENVIRONMENT WITH PERHAPS 1500-2000 J/KG MLCAPE. ALL MODES OF
SEVERE THREAT WOULD BE IN PLAY...INCLUDING ISOLATED TORNADOES AND
LARGER SIZE HAIL ACROSS NORTHWEST IOWA AND ADJACENT LOCATIONS VERY
LATE AFTERNOON AND EARLY EVENING. THE STRONG LINEAR FORCING ALONG
THE FRONT...AND GRADUAL SHIFT IN SHEAR COMPONENT AWAY FROM CROSS
GRADIENT SHOULD SPELL A CHANGE TOWARD LINEAR STRUCTURES WHICH WILL
FAVOR MORE IN THE WAY OF WIND. OVERALL...LOOKING AT THE MOST
SIGNIFICANT THREAT FOR SEVERE...INCLUDING TORNADOES...ACROSS
NORTHWEST IOWA...EASTERN PORTIONS OF SW MN...AND EXTREME NORTHEAST
NEBRASKA...WITH LESSER SEVERE TYPES BACK ACROSS FAR EASTERN SOUTH
DAKOTA AND INTO ADJACENT SW MN. RAINFALL RATES ARE A CONCERN FOR
POTENTIAL FLASH FLOODING... ESPECIALLY FOR URBAN AREAS...AND THOSE
LOCATIONS OF IDA/WOODBURY COUNTY WHICH RECEIVED VERY HEAVY
RAINFALL THE LAST COUPLE OF DAYS.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 435 AM CDT SUN AUG 31 2014

LABOR DAY HOLIDAY SHOULD BY DRY AND COOLER WITH COLD FRONT AND
ASSOCIATED PRECIP EXPECTED TO EXIT OUR FAR SOUTHEAST EARLY IN THE
DAY. WEAK UPPER WAVE COULD BRING SPOTTY SHOWERS AND STORMS TO
WESTERN PORTIONS OF THE AREA LATE IN THE DAY...BUT BETTER CHANCE
LOOKS TO HOLD OFF UNTIL AFTER SUNSET...THOUGH EVEN THIS EXPECTED TO
BE SCATTERED AT BEST WITH MOISTURE/LIFT MAINLY FOCUSED ABOVE 750MB.
HIGHS FOR THE HOLIDAY SHOULD ONLY BE IN THE MID TO UPPER 70S BEHIND
THE EXITING COLD FRONT...WITH TEMPERATURES MONDAY NIGHT COOLING INTO
THE 50S WITH LIGHT WINDS AND CLEARING SKIES LATE AS THE WAVE SHIFTS
EAST. SUNSHINE AND SLIGHTLY WARMER TUESDAY...WITH STRONGER PUSH OF
WARM AIR MOVING THROUGH TUESDAY NIGHT AND WEDNESDAY. CANNOT RULE OUT
SPOTTY PRECIP DEVELOPMENT WITH THE WARM ADVECTION TUESDAY NIGHT...
BUT FORECAST SOUNDINGS LACKING MOISTURE AND WILL LEAVE DRY FOR NOW.
MARGINALLY BETTER PRECIP CHANCE IN OUR NORTHEAST WEDNESDAY NIGHT AS
STRONGER LOW LEVEL JET DEVELOPS ACROSS THE PLAINS...BUT AREAS TO OUR
NORTHEAST APPEAR TO BE MORE FAVORED AREA AT THIS TIME.

ANOTHER STRONGER WAVE AND COOL FRONT EXPECTED TO PUSH THROUGH THE
REGION LATE IN THE WORK WEEK...WITH PRECIP CHANCES RAMPING UP
THURSDAY NIGHT AND FRIDAY. TIMING DIFFERS AMONG THE MODELS...WITH
ECMWF/GEM MOVING THE FRONT AND ASSOCIATED PRECIP SOUTH OF OUR AREA
MORE QUICKLY THAN GFS. WILL HANG ONTO LOW CHANCES...MAINLY SOUTH...
INTO FRIDAY NIGHT TO ACCOUNT FOR SLOWER GFS. LATE WEEK TEMPERATURES
SHOULD STILL BE FAIRLY MILD...WITH HIGHS IN THE UPPER 70S AND 80S
THURSDAY. FASTER ECMWF/GEM ALSO HAVE A STRONGER COLD PUSH...AND IF
THEY DO VERIFY...HIGHS FRIDAY/SATURDAY COULD STRUGGLE TO REACH 70.
HOWEVER GIVEN UNCERTAINTY IN TIMING AT THIS RANGE...WILL STICK CLOSE
TO MODEL CONSENSUS IN THE LOWER TO MID 70S FOR NOW.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1044 PM CDT SAT AUG 30 2014

CONVECTION OVER CENTRAL SOUTH DAKOTA LOOKS TO BE DIMINISHING AS IT
MOVES EASTWARD...THOUGH ISOLATED STORMS MAY PUSH ACROSS THE AREA
OVERNIGHT. WITH THE ISOLATED NATURE OF THE CONVECTION...DID NOT
INCLUDE IN TAFS. BETTER CHANCES OF STORMS WILL OCCUR FROM NEAR THE
INTERSTATE 29 CORRIDOR AND EASTWARD LATER ON SUNDAY
AFTERNOON...EFFECTING THE KFSD AND KSUX TAF SITES INTO SUNDAY
EVENING.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...CHAPMAN
LONG TERM...JH
AVIATION...JM





000
FXUS63 KFSD 310349
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1049 PM CDT SAT AUG 30 2014

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 303 PM CDT SAT AUG 30 2014

STRATUS ALONG AND EAST OF THE JAMES RIVER HAS BEEN QUITE STUBBORN TO
ERODE.  EXPECT STRATUS TO GRADUALLY FALL APART THROUGH THE EVENING
HOURS AS SUPPORT DIES AWAY. WITH FLOW BECOMING LIGHT ACROSS THE
EASTERN CWA...COULD SEE STRATUS REDEVELOP THROUGH THE OVERNIGHT
HOURS AND HAVE KEPT SKY COVER HIGHER.  AFTER 06Z...COULD SEE SOME
ELEVATED CONVECTION ACROSS THE WESTERN HALF OF THE FORECAST
AREA...SHIFTING TOWARDS THE I-29 CORRIDOR AT 12Z.  VERY LIMITED
AMOUNTS OF INSTABILITY ACROSS CENTRAL SOUTH DAKOTA...BUT FURTHER TO
THE EAST...THERE ARE AROUND 500-700 J/KG OF CAPE. WITH STRONG LOW
LEVEL JET...HODOGRAPHS DEPICT STRONGLY VEERING PROFILE. OUTSIDE
ELEVATED HAIL AND WIND THREAT...BUT EXPECT ANY POTENTIAL STORMS TO
REMAIN BELOW SEVERE LIMITS.

EXPECT PARTIAL CLEARING THROUGH THE MORNING HOURS TO ALLOW FOR
INCREASED INSTABILITY AHEAD OF COLD FRONT WORKING THROUGH THE AREA.
SHEAR PROFILES BECOME MUCH MORE LINEAR AHEAD OF THE FRONT...AND
WHILE CAN/T ENTIRELY RULE OUT AN ISOLATED TORNADO WITH INITIAL
CONVECTION...EXPECT MORE OF A HAIL AND WIND THREAT THROUGH THE
AFTERNOON AND EVENING HOURS.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 303 PM CDT SAT AUG 30 2014

SUNDAY NIGHT WILL SEE THUNDERSTORMS IN THE SOUTHEAST CWA AND A FEW
WILL LIKELY STILL BE SEVERE. MOST OF THIS ACTIVITY WILL COME TO AN
END BY MIDNIGHT AS THE STRONG WAVE MOVES THROUGH THE AREA. THIS WILL
SET UP A DRY AND MILD MONDAY WITH NORTHWEST WINDS LIKELY 10 TO 15
MPH...HIGHS IN THE 70S AND DEW POINTS IN THE 50S.

ANOTHER WAVE WILL MOVE THROUGH THE AREA MONDAY NIGHT SWINGING A
SMALL CHANCE FOR SHOWERS AND ISOLATED THUNDERSTORM TO THE REGION.
NOT BANKING ON ANYTHING THAT WOULD CHANGE PLANS AT THIS TIME. WITH
SOME CLOUD COVER AROUND TEMPERATURES WILL LIKELY BOTTOM OUT IN THE
MID 50S MOST LOCATIONS.

TUESDAY WILL LIKELY BE DRY AND A BIT ABOVE NORMAL AS UPPER LEVEL
RIDGING FOLLOWS THE MONDAY NIGHT WAVE. SOUTHWEST WINDS OF 10 TO 15
MPH CAN BE EXPECTED WITH HIGHS IN THE UPPER 70 TO LOWER 80S.

IN THE OUTER PERIODS (WEDNESDAY THROUGH SATURDAY)...FAST WEST TO
SOUTHWEST FLOW ALOFT FROM THE ROCKIES INTO THE DAKOTAS WILL REMAIN
IN PLACE THROUGH THE PERIOD. LOOKS DRY AND PRETTY WARM ON WEDNESDAY
AS SOUTHERLY FLOW STRENGTHENS THROUGH THE DAY. WILL AIM FOR ABOVE
NORMAL TEMPERATURES. A SLIGHTLY STRONGER WAVE WILL MOVE THROUGH THIS
FLOW THURSDAY NIGHT INTO FRIDAY AND BRING A CHANCE FOR SHOWERS AND
THUNDERSTORMS AS WELL AS AN INCREASE IN CLOUD COVER FRIDAY INTO
SATURDAY AS A MID LEVEL BOUNDARY SETTLES INTO THE AREA. THURSDAY
COULD PROVE TO BE A TRANSITION DAY AS COOLER AIR SETTLES IN BUT IF
THE BOUNDARY IS A FEW HOURS SLOWER SOME OF THE AREA COULD BECOME
PRETTY WARM. AFTER THIS BELOW NORMAL TEMPERATURES ARE EXPECTED AS
THE COOLER AIR AND A LOW LEVEL EASTERLY COMPONENT TO THE WIND WILL
LIKELY KEEP THINGS A LITTLE COOLER.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1044 PM CDT SAT AUG 30 2014

CONVECTION OVER CENTRAL SOUTH DAKOTA LOOKS TO BE DIMINISHING AS IT
MOVES EASTWARD...THOUGH ISOLATED STORMS MAY PUSH ACROSS THE AREA
OVERNIGHT. WITH THE ISOLATED NATURE OF THE CONVECTION...DID NOT
INCLUDE IN TAFS. BETTER CHANCES OF STORMS WILL OCCUR FROM NEAR THE
INTERSTATE 29 CORRIDOR AND EASTWARD LATER ON SUNDAY
AFTERNOON...EFFECTING THE KFSD AND KSUX TAF SITES INTO SUNDAY
EVENING.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...
LONG TERM...08
AVIATION...JM




000
FXUS63 KFSD 310349
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1049 PM CDT SAT AUG 30 2014

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 303 PM CDT SAT AUG 30 2014

STRATUS ALONG AND EAST OF THE JAMES RIVER HAS BEEN QUITE STUBBORN TO
ERODE.  EXPECT STRATUS TO GRADUALLY FALL APART THROUGH THE EVENING
HOURS AS SUPPORT DIES AWAY. WITH FLOW BECOMING LIGHT ACROSS THE
EASTERN CWA...COULD SEE STRATUS REDEVELOP THROUGH THE OVERNIGHT
HOURS AND HAVE KEPT SKY COVER HIGHER.  AFTER 06Z...COULD SEE SOME
ELEVATED CONVECTION ACROSS THE WESTERN HALF OF THE FORECAST
AREA...SHIFTING TOWARDS THE I-29 CORRIDOR AT 12Z.  VERY LIMITED
AMOUNTS OF INSTABILITY ACROSS CENTRAL SOUTH DAKOTA...BUT FURTHER TO
THE EAST...THERE ARE AROUND 500-700 J/KG OF CAPE. WITH STRONG LOW
LEVEL JET...HODOGRAPHS DEPICT STRONGLY VEERING PROFILE. OUTSIDE
ELEVATED HAIL AND WIND THREAT...BUT EXPECT ANY POTENTIAL STORMS TO
REMAIN BELOW SEVERE LIMITS.

EXPECT PARTIAL CLEARING THROUGH THE MORNING HOURS TO ALLOW FOR
INCREASED INSTABILITY AHEAD OF COLD FRONT WORKING THROUGH THE AREA.
SHEAR PROFILES BECOME MUCH MORE LINEAR AHEAD OF THE FRONT...AND
WHILE CAN/T ENTIRELY RULE OUT AN ISOLATED TORNADO WITH INITIAL
CONVECTION...EXPECT MORE OF A HAIL AND WIND THREAT THROUGH THE
AFTERNOON AND EVENING HOURS.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 303 PM CDT SAT AUG 30 2014

SUNDAY NIGHT WILL SEE THUNDERSTORMS IN THE SOUTHEAST CWA AND A FEW
WILL LIKELY STILL BE SEVERE. MOST OF THIS ACTIVITY WILL COME TO AN
END BY MIDNIGHT AS THE STRONG WAVE MOVES THROUGH THE AREA. THIS WILL
SET UP A DRY AND MILD MONDAY WITH NORTHWEST WINDS LIKELY 10 TO 15
MPH...HIGHS IN THE 70S AND DEW POINTS IN THE 50S.

ANOTHER WAVE WILL MOVE THROUGH THE AREA MONDAY NIGHT SWINGING A
SMALL CHANCE FOR SHOWERS AND ISOLATED THUNDERSTORM TO THE REGION.
NOT BANKING ON ANYTHING THAT WOULD CHANGE PLANS AT THIS TIME. WITH
SOME CLOUD COVER AROUND TEMPERATURES WILL LIKELY BOTTOM OUT IN THE
MID 50S MOST LOCATIONS.

TUESDAY WILL LIKELY BE DRY AND A BIT ABOVE NORMAL AS UPPER LEVEL
RIDGING FOLLOWS THE MONDAY NIGHT WAVE. SOUTHWEST WINDS OF 10 TO 15
MPH CAN BE EXPECTED WITH HIGHS IN THE UPPER 70 TO LOWER 80S.

IN THE OUTER PERIODS (WEDNESDAY THROUGH SATURDAY)...FAST WEST TO
SOUTHWEST FLOW ALOFT FROM THE ROCKIES INTO THE DAKOTAS WILL REMAIN
IN PLACE THROUGH THE PERIOD. LOOKS DRY AND PRETTY WARM ON WEDNESDAY
AS SOUTHERLY FLOW STRENGTHENS THROUGH THE DAY. WILL AIM FOR ABOVE
NORMAL TEMPERATURES. A SLIGHTLY STRONGER WAVE WILL MOVE THROUGH THIS
FLOW THURSDAY NIGHT INTO FRIDAY AND BRING A CHANCE FOR SHOWERS AND
THUNDERSTORMS AS WELL AS AN INCREASE IN CLOUD COVER FRIDAY INTO
SATURDAY AS A MID LEVEL BOUNDARY SETTLES INTO THE AREA. THURSDAY
COULD PROVE TO BE A TRANSITION DAY AS COOLER AIR SETTLES IN BUT IF
THE BOUNDARY IS A FEW HOURS SLOWER SOME OF THE AREA COULD BECOME
PRETTY WARM. AFTER THIS BELOW NORMAL TEMPERATURES ARE EXPECTED AS
THE COOLER AIR AND A LOW LEVEL EASTERLY COMPONENT TO THE WIND WILL
LIKELY KEEP THINGS A LITTLE COOLER.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1044 PM CDT SAT AUG 30 2014

CONVECTION OVER CENTRAL SOUTH DAKOTA LOOKS TO BE DIMINISHING AS IT
MOVES EASTWARD...THOUGH ISOLATED STORMS MAY PUSH ACROSS THE AREA
OVERNIGHT. WITH THE ISOLATED NATURE OF THE CONVECTION...DID NOT
INCLUDE IN TAFS. BETTER CHANCES OF STORMS WILL OCCUR FROM NEAR THE
INTERSTATE 29 CORRIDOR AND EASTWARD LATER ON SUNDAY
AFTERNOON...EFFECTING THE KFSD AND KSUX TAF SITES INTO SUNDAY
EVENING.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

SHORT TERM...
LONG TERM...08
AVIATION...JM





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