000
FXUS63 KBIS 190124
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
824 PM CDT SAT MAY 18 2013

.UPDATE...
ISSUED AT 824 PM CDT SAT MAY 18 2013

SEVERE THUNDERSTORM WATCH CONTINUES UNTIL 1 AM CDT SUNDAY FOR
SOUTH CENTRAL NORTH DAKOTA AND PORTIONS OF SOUTHWEST NORTH DAKOTA.
LATEST RADAR IMAGERY SHOWS A LARGE ARE OF MODERATE TO HEAVY
SHOWERS AND THUNDERSTORMS...ISOLATED SEVERE WITH LARGE HAIL AND
HEAVY RAINFALL THE MAIN THREATS THUS FAR. THIS IS ESSENTIALLY
OCCURRING FROM NEAR TUTTLE...SOUTHWEST TO PRAIRIE NIGHTS RESORT.
WATCHING THUNDERSTORMS UPSTREAM IN SOUTH DAKOTA FOR POTENTIAL
HYDRO ISSUES LATER TONIGHT AS MORE HEAVY RAIN IS FORECAST TO
ADVANCE INTO SOUTHEAST NORTH DAKOTA. STILL HAVE THUNDERSTORMS IN
EASTERN MONTANA AND FAR WESTERN NORTH DAKOTA...BUT MIGHT SCALE
BACK THE SEVERE THUNDERSTORM WATCH IN THE NEXT COUPLE OF HOURS
ACROSS PORTIONS OF THE SOUTHWEST.

UPDATE ISSUED AT 554 PM CDT SAT MAY 18 2013

A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR MOST OF SOUTH
CENTRAL AND PORTIONS OF SOUTHWESTERN NORTH DAKOTA. MONITORING
RADAR AND THIS WILL BE THE FOCUS THROUGH THE EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 302 PM CDT SAT MAY 18 2013

THE MAIN FOCUS THIS AFTERNOON IS ON THE POTENTIAL FOR SEVERE
THUNDERSTORMS THROUGH TONIGHT.

LOW LEVEL CONVERGENCE STRETCHING FROM DICKINSON TO THE BLACK HILLS
HAS PROVEN TO BE SUFFICIENT TO BREAK THE CAP THIS AFTERNOON. VISIBLE
SATELLITE INDICATES SOME AGITATED CUMULUS THERE...AND AT LEAST ONE
THUNDERSTORM HAS BEEN WARNED THERE. BASED ON ANVIL BLOW
OFF...THERE WILL PROBABLY BE ONLY LIMITED SURFACE HEATING INTO
NORTHWESTERN SOUTH DAKOTA...SO IT APPEARS THAT THE BEST CHANCE FOR
SEVERE WILL HOLD OFF AT LEAST A FEW MORE HOURS UNTIL MID LEVEL
HEIGHT FALLS SPREAD INTO THE CENTRAL DAKOTAS ATOP BETTER
INSTABILITY AND MORE FAVORABLE SHEAR THAN THAT CURRENTLY OVER
SOUTHWESTERN NORTH DAKOTA. THIS IS SUPPORTED BY THE SHOWER THAT
FORMED AROUND 19 UTC AND FAILED TO GAIN STEAM NEAR HETTINGER.

USING VISIBLE SATELLITE AND RADAR...IT APPEARS THAT THE MOST
LIKELY SCENARIO IS FOR CONVECTION TO SLOWLY SPREAD INTO
SOUTHWESTERN NORTH DAKOTA OVER THE NEXT 5 HOURS...THEN MOVE
EASTWARD. THESE STORMS SHOULD THEN PROPAGATE EAST-NORTHEASTWARD
INTO SOUTHEASTERN NORTH DAKOTA...WITH THE BEST CHANCE FOR SEVERE
WEATHER BEING ALONG AND SOUTH OF I-94.

THEREAFTER...LINGERING SHOWERS AND THUNDERSTORMS ARE FORECAST
THROUGH THE WEEKEND AS BROAD LOW PRESSURE IS CUT OFF OVER THE
NORTHERN PLAINS.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 302 PM CDT SAT MAY 18 2013

THE MAIN FORECAST HIGHLIGHT OF THE EXTENDED PERIOD WILL BE
PRECIPITATION CHANCES AND AMOUNTS SUNDAY NIGHT THROUGH LATE
TUESDAY.

THERE IS STILL SOME DISAGREEMENT AMONGST THE 12Z DETERMINISTIC
MODELS REGARDING THE PLACEMENT AND MOVEMENT OF THE H500 CLOSED UPPER
LEVEL LOW OVER THE NORTHERN PLAINS. THE 12Z GFS KEEPS THE H500 LOW A
BIT FASTER AND FURTHER SOUTH THAN THE GEFS/ECWMF/GEM MONDAY AND
TUESDAY...WHICH INTRODUCES SOME DIFFERENCES IN THE TIMING AND
PLACEMENT OF PRECIPITATION ACROSS NORTH DAKOTA EARLY IN THE
EXTENDED. AS A CONSEQUENCE HAVE KEPT CHANCE/LIKELY POPS THROUGH MID
TUESDAY BEFORE BRINGING DOWN POPS FROM NORTHWEST TO SOUTHEAST AS THE
H500 LOW SLOWLY DRIFTS EAST AND AWAY FROM THE NORTHERN PLAINS. FOR
QPF...HAVE USED A BLEND OF MODEL GUIDANCE AS WELL AS THE WPC
GUIDANCE FOR AMOUNTS...WHICH HAS AN ADDITIONAL 1 TO 2 INCHES OF
RAINFALL FROM SUNDAY EVENING THROUGH LATE TUESDAY FOR LOCATIONS
SOUTH OF STATE HIGHWAY 2. TO THE NORTH (INCLUDING THE SOURIS RIVER
BASIN)...UP TO AN INCH OF ADDITIONAL RAINFALL IS POSSIBLE. AS SAID
WITH PREVIOUS FORECAST ISSUANCES...SIGNIFICANT RESPONSES ARE NOT
EXPECTED ON AREA RIVERS...BUT WILL BE WATCHING SMALLER CREEKS AND
STREAMS...AS WELL AS THE POTENTIAL FOR URBAN FLOODING.

BEYOND WEDNESDAY...THE ECWMF AND GFS SOLUTIONS DIVERGE WITH THE
PLACEMENT AND MOVEMENT OF THE NEXT WESTERN CONUS UPPER LEVEL
TROUGH...HOWEVER...THERE IS AGREEMENT THAT AN UPPER LEVEL RIDGE WILL
BEGIN TO BUILD OVER THE CENTRAL US AS THE AFOREMENTIONED CLOSED LOW
DEPARTS EAST. A SLOW WARMING TREND THROUGH THE END OF THIS COMING
WEEK AND CLEARING SKIES THURSDAY ARE EXPECTED ACROSS NORTH DAKOTA.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 554 PM CDT SAT MAY 18 2013

SCATTERED SHOWERS AND THUNDERSTORMS WITH MVFR TO IFR CIGS/VSBYS
THROUGH THE PERIOD. THE FOCUS SATURDAY NIGHT INTO 12Z SUNDAY WILL
BE OVER KBIS/KJMS. AFTER 12Z SUNDAY...EXPECT WIDESPREAD SHOWERS
AND THUNDERSTORMS TO INITIATE AND AFFECT ALL AERODROMES.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...KS
SHORT TERM...JWS
LONG TERM...LTH
AVIATION...KS

000
FXUS63 KFGF 190016
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
716 PM CDT SAT MAY 18 2013

.UPDATE...
ISSUED AT 716 PM CDT SAT MAY 18 2013

THE SITUATION FOR TONIGHT IS BECOMING A LITTLE MORE CLEAR. THERE
IS SUBTLE SHORTWAVE ACROSS THE WESTERN DAKOTAS WHICH HAS INITIATED
A THUNDERSTORM COMPLEX THAT IS HEADING TO THE EAST. THERE IS ALSO
AN ISOLATED SEVERE STORM WITHIN BECKER COUNTY ALONG A WEAK
SURFACE BOUNDARY...AND ANOTHER AREA OF STORMS JUST SOUTH OF THE FA
ALONG ANOTHER WEAK BOUNDARY. THE GENERAL IDEA IS THAT THE COMPLEX
TO THE WEST WILL MOVE THROUGH THE REGION LATER THIS EVENING AND
OVERNIGHT. MEANWHILE...ACTIVITY FROM THE SOUTH WILL GROW IN
COVERAGE AND MOVE INTO THE SOUTHERN FA (GRADUALLY MOVING NORTH
THROUGH THE REGION ON SUNDAY). UPDATED POP GRIDS TO REFLECT THIS
THINKING (ISOLATED THIS EVENING WITH POPS INCREASING).

OVERALL THE SEVERE THREAT APPEARS LIMITED...WITH THE BEST THREAT
ACROSS THE SOUTHERN FA WHERE MLCAPE IS CURRENTLY AROUND 1000 J/KG.
THE ISOLATED ACTIVITY AHEAD OF THE WESTERN COMPLEX HAS THE
POTENTIAL TO PRODUCE LARGE HAIL AND STRONG WIND GUSTS...BUT
COVERAGE WILL BE LIMITED. THE MAIN CONCERN WILL BE THE COMPLEX
APPROACHING FROM THE WEST. LATEST HRRR INDICATES THE POTENTIAL FOR
BOWING AND STRONG WINDS ACROSS SOUTHERN NORTH DAKOTA. NOT SURE IF
THIS WILL HOLD TOGETHER BY THE TIME IT ENTERS SE ND...BUT WILL
MONITOR.

ALSO STILL NOT SURE ABOUT A FLASH FLOOD THREAT. WILL MONITOR
TRENDS AND THE SPEED OF THESE STORM OVER THE NEXT FEW HOURS AND
ATTEMPT TO DETERMINE IF HEAVY RAIN IN A SHORT DURATION IS POSSIBLE
TONIGHT. HEAVY RAIN WILL OCCUR...JUST NOT SURE IF THE STORMS WILL
BE MOVING SLOW ENOUGH TO PRODUCE FLASH FLOODING.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 300 PM CDT SAT MAY 18 2013

ALL EYES ON ANY CONVECTIVE DEVELOPMENT LATE THIS AFTN-EVE IN SE
ND-WCNTRL MN. SFC MAP SHOWS A BROAD SFC LOW IN THE MOBRIDGE SD
AREA WITH A BOUNDARY (COULD BE CALLED A WARM FRONT) FROM MOBRIDGE
TO OAKES THEN TO VALLEY CITY THEN TO HILLSBORO THEN EAST TO NORTH
OF DTL-PKD-BRD THEN INTO FAR NW WISCONSIN. IN FAR SE ND AND
ADJACENT PARTS OF WCNTRL CLOUDS CLEARED OUT ENOUGH TODAY FOR SFC
HEATING AND TEMPS IN THE 77 TO 81 DEGREE RANGE. SATELLITE SHOWS
WHAT APPEARS TO BE A CUMULUS CLOUD BOUNDARY FROM HILLSBORO TO
ALONG CLAY-NORMAN CO LINE TO NORTH OF PARK RAPIDS. SOUTH WINDS
SOUTH OF THIS FEATURE NR 10-13 KTS WHILE NORTH WINDS 5-8 KTS
NORTH OF THIS FEATURE. SPC SHOWS LITTLE CIN AND 1500 J/KG CAPE AND
SUFFICIENT BULK SHEAR. BUT UPPER LEVELS DONT SHOW ANY BIG THING TO
SET STUFF OFF. 17-18Z HRRR REFLECTIVITY DOES SHOW ONE CELL TRYING
TO GET GOING IN NORMAN CO. MN 22-23Z PD BUT THEN IT DISSIPATES
THIS EVE.

MUCH OF NORTHEAST SD HAS SEEN HIGH CLOUDS TODAY AND DEW PTS IN THE
50S AND SPC DOES HAVE SOME SFC BASED CIN IN THIS REGION. THUS MAY
BE HARD TO GET ANYTHING GOING THERE. BUT HRRR WANTS TO GENERATE
SOME ACTIVITY AXN-STC AREA BY 03Z.

ALSO SOME STORMS NR BLACK HILLS IN WRN SD. SOME WRF MODELS
INDICATE THIS AREA ORGANIZING MUCH LIKE LAST EVENING AND MOVING
EAST-NORTHEAST INTO SE ND-WCNTRL MN OVERNIGHT. SO VARIOUS
SCENERIOS TO PLAY OUT.

OVERALL WOULD EXPECT ORGANIZATION OF SOME ACTIVITY THIS EVE IN
ND/SD/MN BORDER REGIONS AND THEN SPREAD NORTH AND EAST TONIGHT SO
WILL STICK WITH HIGH POPS TONIGHT THOUGH CONFIDENCE AT ANY ONE
HOUR IS LOW. ALSO QPF AMOUNT IS NOT CERTAIN. PLUS ONLY AREA THAT
MUCH MORE THAN 1 INCH OF RAIN LAST NIGHT WAS EASTERN OTTER TAIL
COUNTY WITH 0.50 TO 1 INCH NRN WILKIN-SE CLAY INTO WADENA
COUNTIES. THIS AREA COULD TAKE THE RAIN. OTHERWISE...RAIN AMOUNTS
IN THE VALLEY WERE MOSTLY 0.50 OR LESS WITH A FEW EXCEPTIONS. WITH
UNCERTAINITY IN HOW THINGS WILL PLAY OUT TONIGHT DID NOT FEEL
CONFIDENT IN ISSUING ANY FLASH FLOOD WATCHES FOR OUR FCST AREA.

MODELS ACTUALLY BRING IN HIGHER PWAT (1.6) INTO AREA SUN AFTN-NIGH IN
GENERAL RAINFALL AROUND THE UPPER LOW IN SD AND THIS IS IN WHEN
MOST WIDESPREAD HEAVIER RAINFALL MAY OCCUR. THUS IF TRUE...GIVES
US TIME TO SEE WHAT FALLS THIS EVE BEFORE ISSUING ANY HEADLINES.
KEPT HIGH POPS SUNDAY INTO SUN NIGHT MOST ALL AREAS.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 300 PM CDT SAT MAY 18 2013

UPR LOW AND SFC LOW WILL BE OVER SRN SD MONDAY INTO TUESDAY WITH
MOISTURE WRAPPING AROUND INTO ND/NW MN MON-TUES PERIOD WITH
GENERAL RAINFALL. KEPT POPS HIGH.

FOR TUESDAY NIGHT-FRIDAY...MODELS HAVE BEEN MOST CONSISTENT IN
BEGINNING TO MOVE THE STACKED NRN PLAINS LOW PRESSURE SYSTEM EWD
IN THE MID WEEK PERIOD. TUESDAY NIGHT INTO WEDNESDAY SHOWS THE
TAPPERING OFF OF VERY LIGHT RAIN WITH PERSISTENT NORTH-EASTERLY
BLAYER WINDS. INTRUDING DRY AIR FROM WRN ONT SHUD LEAD TO MARKEDLY
DIMINISHING CLOUD CLOVER WED EVENING. INCREASING HIGH PRESSURE
OVER WRN ONT AND THE LK SUPERIOR AREA ON THURS AND FRI SHUD SWING
WINDS FROM THE SOOUH EAST AND KEEP AN OVERALL DRYING AIRMASS OVR
THE RRV AND MOST OF MINNESOTA. A WARMIG RIDGE ALOFT AND INCREASED
LOW PRESSURE IN EASTERN MT DOES INCREASE THE RISK FOR SCT SHOWERS
AND TSTMS INTO EASTERN ND BY LATE FRIDAY AND ACROSS THE FA BY
SATURDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 716 PM CDT SAT MAY 18 2013

IFR/LIFR CIGS AFFECTING KBJI AND KDVL...WITH MVFR CIGS AFFECTING
KTVF AND KGFK...AS THESE SITE ARE WITHIN LOW LEVEL NORTHERLY FLOW.
NOT IF THESE CONDITIONS WILL CONTINUE THROUGH THE NIGHT. MOST
GUIDANCE SUGGESTS THAT AN AREA OF THUNDERSTORMS AND/OR SHOWERS
WILL MOVE THROUGH THESE SITES...WHICH SHOULD BRIEFLY RAISE CIGS.
UNTIL THEN...EXPECT THE LOWER CIGS TO CONTINUE. CIGS SHOULD LOWER
THROUGH THE DAY ON SUNDAY WITH SHOWER CHANCES INCREASING. FOR
KFAR...EXPECT THUNDER CHANCES TO INCRASE BY MIDNIGHT...ALONG WITH
LOWERING CIGS.

&&

.HYDROLOGY...
ISSUED AT 300 PM CDT SAT MAY 18 2013

WHEN NCRFC RAN THE MODEL TODAY USING 24 HOUR QPF IT BROUGHT SEVERAL
POINTS ABOVE FLOOD STAGE. THESE INCLUDE FARGO/SABIN/DILWORTH/HAWLEY
AND HENDRUM. SINCE THESE RISES ARE BASED ON FORECAST PCPN WENT AHEAD
AND ISSUED A RIVER POINT FLOOD WATCH FOR THESE 5 POINTS. THE FORECAST
QPF ALSO BROUGHT WAHPETON/EAST GRAND FORKS AND OSLO BACK ABOVE
ACTION STAGE SO ISSUED RIVER STATEMENTS ON THESE. ONLY DRAYTON AND
PEMBINA REMAIN IN A FLOOD STATEMENT.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...TG
SHORT TERM...RIDDLE
LONG TERM...RIDDLE/GUST
AVIATION...TG
HYDROLOGY...GODON

000
FXUS63 KBIS 182254
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
554 PM CDT SAT MAY 18 2013

.UPDATE...
ISSUED AT 554 PM CDT SAT MAY 18 2013

A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR MOST OF SOUTH
CENTRAL AND PORTIONS OF SOUTHWESTERN NORTH DAKOTA. MONITORING
RADAR AND THIS WILL BE THE FOCUS THROUGH THE EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 302 PM CDT SAT MAY 18 2013

THE MAIN FOCUS THIS AFTERNOON IS ON THE POTENTIAL FOR SEVERE
THUNDERSTORMS THROUGH TONIGHT.

LOW LEVEL CONVERGENCE STRETCHING FROM DICKINSON TO THE BLACK HILLS
HAS PROVEN TO BE SUFFICIENT TO BREAK THE CAP THIS AFTERNOON. VISIBLE
SATELLITE INDICATES SOME AGITATED CUMULUS THERE...AND AT LEAST ONE
THUNDERSTORM HAS BEEN WARNED THERE. BASED ON ANVIL BLOW
OFF...THERE WILL PROBABLY BE ONLY LIMITED SURFACE HEATING INTO
NORTHWESTERN SOUTH DAKOTA...SO IT APPEARS THAT THE BEST CHANCE FOR
SEVERE WILL HOLD OFF AT LEAST A FEW MORE HOURS UNTIL MID LEVEL
HEIGHT FALLS SPREAD INTO THE CENTRAL DAKOTAS ATOP BETTER
INSTABILITY AND MORE FAVORABLE SHEAR THAN THAT CURRENTLY OVER
SOUTHWESTERN NORTH DAKOTA. THIS IS SUPPORTED BY THE SHOWER THAT
FORMED AROUND 19 UTC AND FAILED TO GAIN STEAM NEAR HETTINGER.

USING VISIBLE SATELLITE AND RADAR...IT APPEARS THAT THE MOST
LIKELY SCENARIO IS FOR CONVECTION TO SLOWLY SPREAD INTO
SOUTHWESTERN NORTH DAKOTA OVER THE NEXT 5 HOURS...THEN MOVE
EASTWARD. THESE STORMS SHOULD THEN PROPAGATE EAST-NORTHEASTWARD
INTO SOUTHEASTERN NORTH DAKOTA...WITH THE BEST CHANCE FOR SEVERE
WEATHER BEING ALONG AND SOUTH OF I-94.

THEREAFTER...LINGERING SHOWERS AND THUNDERSTORMS ARE FORECAST
THROUGH THE WEEKEND AS BROAD LOW PRESSURE IS CUT OFF OVER THE
NORTHERN PLAINS.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 302 PM CDT SAT MAY 18 2013

THE MAIN FORECAST HIGHLIGHT OF THE EXTENDED PERIOD WILL BE
PRECIPITATION CHANCES AND AMOUNTS SUNDAY NIGHT THROUGH LATE
TUESDAY.

THERE IS STILL SOME DISAGREEMENT AMONGST THE 12Z DETERMINISTIC
MODELS REGARDING THE PLACEMENT AND MOVEMENT OF THE H500 CLOSED UPPER
LEVEL LOW OVER THE NORTHERN PLAINS. THE 12Z GFS KEEPS THE H500 LOW A
BIT FASTER AND FURTHER SOUTH THAN THE GEFS/ECWMF/GEM MONDAY AND
TUESDAY...WHICH INTRODUCES SOME DIFFERENCES IN THE TIMING AND
PLACEMENT OF PRECIPITATION ACROSS NORTH DAKOTA EARLY IN THE
EXTENDED. AS A CONSEQUENCE HAVE KEPT CHANCE/LIKELY POPS THROUGH MID
TUESDAY BEFORE BRINGING DOWN POPS FROM NORTHWEST TO SOUTHEAST AS THE
H500 LOW SLOWLY DRIFTS EAST AND AWAY FROM THE NORTHERN PLAINS. FOR
QPF...HAVE USED A BLEND OF MODEL GUIDANCE AS WELL AS THE WPC
GUIDANCE FOR AMOUNTS...WHICH HAS AN ADDITIONAL 1 TO 2 INCHES OF
RAINFALL FROM SUNDAY EVENING THROUGH LATE TUESDAY FOR LOCATIONS
SOUTH OF STATE HIGHWAY 2. TO THE NORTH (INCLUDING THE SOURIS RIVER
BASIN)...UP TO AN INCH OF ADDITIONAL RAINFALL IS POSSIBLE. AS SAID
WITH PREVIOUS FORECAST ISSUANCES...SIGNIFICANT RESPONSES ARE NOT
EXPECTED ON AREA RIVERS...BUT WILL BE WATCHING SMALLER CREEKS AND
STREAMS...AS WELL AS THE POTENTIAL FOR URBAN FLOODING.

BEYOND WEDNESDAY...THE ECWMF AND GFS SOLUTIONS DIVERGE WITH THE
PLACEMENT AND MOVEMENT OF THE NEXT WESTERN CONUS UPPER LEVEL
TROUGH...HOWEVER...THERE IS AGREEMENT THAT AN UPPER LEVEL RIDGE WILL
BEGIN TO BUILD OVER THE CENTRAL US AS THE AFOREMENTIONED CLOSED LOW
DEPARTS EAST. A SLOW WARMING TREND THROUGH THE END OF THIS COMING
WEEK AND CLEARING SKIES THURSDAY ARE EXPECTED ACROSS NORTH DAKOTA.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 554 PM CDT SAT MAY 18 2013

SCATTERED SHOWERS AND THUNDERSTORMS WITH MVFR TO IFR CIGS/VSBYS
THROUGH THE PERIOD. THE FOCUS SATURDAY NIGHT INTO 12Z SUNDAY WILL
BE OVER KBIS/KJMS. AFTER 12Z SUNDAY...EXPECT WIDESPREAD SHOWERS
AND THUNDERSTORMS TO INITIATE AND AFFECT ALL AERODROMES.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...KS
SHORT TERM...JWS
LONG TERM...LTH
AVIATION...KS

000
FXUS63 KFGF 182014
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
314 PM CDT SAT MAY 18 2013

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 300 PM CDT SAT MAY 18 2013

ALL EYES ON ANY CONVECTIVE DEVELOPMENT LATE THIS AFTN-EVE IN SE
ND-WCNTRL MN. SFC MAP SHOWS A BROAD SFC LOW IN THE MOBRIDGE SD
AREA WITH A BOUNDARY (COULD BE CALLED A WARM FRONT) FROM MOBRIDGE
TO OAKES THEN TO VALLEY CITY THEN TO HILLSBORO THEN EAST TO NORTH
OF DTL-PKD-BRD THEN INTO FAR NW WISCONSIN. IN FAR SE ND AND
ADJACENT PARTS OF WCNTRL CLOUDS CLEARED OUT ENOUGH TODAY FOR SFC
HEATING AND TEMPS IN THE 77 TO 81 DEGREE RANGE. SATELLITE SHOWS
WHAT APPEARS TO BE A CUMULUS CLOUD BOUNDARY FROM HILLSBORO TO
ALONG CLAY-NORMAN CO LINE TO NORTH OF PARK RAPIDS. SOUTH WINDS
SOUTH OF THIS FEATURE NR 10-13 KTS WHILE NORTH WINDS 5-8 KTS
NORTH OF THIS FEATURE. SPC SHOWS LITTLE CIN AND 1500 J/KG CAPE AND
SUFFICIENT BULK SHEAR. BUT UPPER LEVELS DONT SHOW ANY BIG THING TO
SET STUFF OFF. 17-18Z HRRR REFLECTIVITY DOES SHOW ONE CELL TRYING
TO GET GOING IN NORMAN CO. MN 22-23Z PD BUT THEN IT DISSIPATES
THIS EVE.

MUCH OF NORTHEAST SD HAS SEEN HIGH CLOUDS TODAY AND DEW PTS IN THE
50S AND SPC DOES HAVE SOME SFC BASED CIN IN THIS REGION. THUS MAY
BE HARD TO GET ANYTHING GOING THERE. BUT HRRR WANTS TO GENERATE
SOME ACTIVITY AXN-STC AREA BY 03Z.

ALSO SOME STORMS NR BLACK HILLS IN WRN SD. SOME WRF MODELS
INDICATE THIS AREA ORGANIZING MUCH LIKE LAST EVENING AND MOVING
EAST-NORTHEAST INTO SE ND-WCNTRL MN OVERNIGHT. SO VARIOUS
SCENERIOS TO PLAY OUT.

OVERALL WOULD EXPECT ORGANIZATION OF SOME ACTIVITY THIS EVE IN
ND/SD/MN BORDER REGIONS AND THEN SPREAD NORTH AND EAST TONIGHT SO
WILL STICK WITH HIGH POPS TONIGHT THOUGH CONFIDENCE AT ANY ONE
HOUR IS LOW. ALSO QPF AMOUNT IS NOT CERTAIN. PLUS ONLY AREA THAT
MUCH MORE THAN 1 INCH OF RAIN LAST NIGHT WAS EASTERN OTTER TAIL
COUNTY WITH 0.50 TO 1 INCH NRN WILKIN-SE CLAY INTO WADENA
COUNTIES. THIS AREA COULD TAKE THE RAIN. OTHERWISE...RAIN AMOUNTS
IN THE VALLEY WERE MOSTLY 0.50 OR LESS WITH A FEW EXCEPTIONS. WITH
UNCERTAINITY IN HOW THINGS WILL PLAY OUT TONIGHT DID NOT FEEL
CONFIDENT IN ISSUING ANY FLASH FLOOD WATCHES FOR OUR FCST AREA.

MODELS ACTUALLY BRING IN HIGHER PWAT (1.6) INTO AREA SUN AFTN-NIGH IN
GENERAL RAINFALL AROUND THE UPPER LOW IN SD AND THIS IS IN WHEN
MOST WIDESPREAD HEAVIER RAINFALL MAY OCCUR. THUS IF TRUE...GIVES
US TIME TO SEE WHAT FALLS THIS EVE BEFORE ISSUING ANY HEADLINES.
KEPT HIGH POPS SUNDAY INTO SUN NIGHT MOST ALL AREAS.


.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 300 PM CDT SAT MAY 18 2013

UPR LOW AND SFC LOW WILL BE OVER SRN SD MONDAY INTO TUESDAY WITH
MOISTURE WRAPPING AROUND INTO ND/NW MN MON-TUES PERIOD WITH
GENERAL RAINFALL. KEPT POPS HIGH.

FOR TUESDAY NIGHT-FRIDAY...MODELS HAVE BEEN MOST CONSISTENT IN
BEGINNING TO MOVE THE STACKED NRN PLAINS LOW PRESSURE SYSTEM EWD
IN THE MID WEEK PERIOD. TUESDAY NIGHT INTO WEDNESDAY SHOWS THE
TAPPERING OFF OF VERY LIGHT RAIN WITH PERSISTENT NORTH-EASTERLY
BLAYER WINDS. INTRUDING DRY AIR FROM WRN ONT SHUD LEAD TO MARKEDLY
DIMINISHING CLOUD CLOVER WED EVENING. INCREASING HIGH PRESSURE
OVER WRN ONT AND THE LK SUPERIOR AREA ON THURS AND FRI SHUD SWING
WINDS FROM THE SOOUH EAST AND KEEP AN OVERALL DRYING AIRMASS OVR
THE RRV AND MOST OF MINNESOTA. A WARMIG RIDGE ALOFT AND INCREASED
LOW PRESSURE IN EASTERN MT DOES INCREASE THE RISK FOR SCT SHOWERS
AND TSTMS INTO EASTERN ND BY LATE FRIDAY AND ACROSS THE FA BY
SATURDAY.


&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 107 PM CDT SAT MAY 18 2013

ACROSS NERN ND AND NRWN MN...AREAS OF IFR TO LIFR CIGS AND VSBYS
ALG AND NORTH OF U.S. HWY 2 WILL SLOWLY LIFT AND SHIFT NORTHWARD
THIS AFTERNOON...WITH SCT MVFR CIGS LIKELY TO PERSIST INTO THE
EVENING. SCT TSTMS ARE EXPECTED TO DEVELOP FROM LATE AFTERNOON
INTO THE EARLY EVENING...BECOMING MORE NUMEROUS INTO THE LATE
EVENING. ACROSS SERN ND INTO WCNTRL MN...AREAS OF LIFR TO IFR CIGS
AND VSBYS ALG AND EAST OF AN AXN-BJI LINE WILL SLOWLY LIFT AND
SHIFT NORTHEASTWARD THROUGH THIS AFTERNOON...WITH SCT MVFR CIGS
LIKELY TO PERSIST INTO THE EVENING. OTHERWISE...FAIR SKIES OVER
THE SOUTHERN RRV WILL ALLOW FOR INCREASED SFC HEATING AND THE
DEVELOPMENT OF SCT TSTMS /WITH ISOLD LARGE HAIL/ FROM MID
AFTERNOON INTO THE EARLY EVENING...BECOMING MORE NUMEROUS INTO
MIDNIGHT.


&&

.HYDROLOGY...
ISSUED AT 300 PM CDT SAT MAY 18 2013

WHEN NCRFC RAN THE MODEL TODAY USING 24 HOUR QPF IT BROUGHT SEVERAL
POINTS ABOVE FLOOD STAGE. THESE INCLUDE FARGO/SABIN/DILWORTH/HAWLEY
AND HENDRUM. SINCE THESE RISES ARE BASED ON FORECAST PCPN WENT AHEAD
AND ISSUED A RIVER POINT FLOOD WATCH FOR THESE 5 POINTS. THE FORECAST
QPF ALSO BROUGHT WAHPETON/EAST GRAND FORKS AND OSLO BACK ABOVE
ACTION STAGE SO ISSUED RIVER STATEMENTS ON THESE. ONLY DRAYTON AND
PEMBINA REMAIN IN A FLOOD STATEMENT.


&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

SHORT TERM...RIDDLE
LONG TERM...RIDDLE/GUST
AVIATION...GUST
HYDROLOGY...GODON

000
FXUS63 KBIS 182004
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
304 PM CDT SAT MAY 18 2013

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 302 PM CDT SAT MAY 18 2013

THE MAIN FOCUS THIS AFTERNOON IS ON THE POTENTIAL FOR SEVERE
THUNDERSTORMS THROUGH TONIGHT.

LOW LEVEL CONVERGENCE STRETCHING FROM DICKINSON TO THE BLACK HILLS
HAS PROVEN TO BE SUFFICIENT TO BREAK THE CAP THIS AFTERNOON. VISIBLE
SATELLITE INDICATES SOME AGITATED CUMULUS THERE...AND AT LEAST ONE
THUNDERSTORM HAS BEEN WARNED THERE. BASED ON ANVIL BLOW
OFF...THERE WILL PROBABLY BE ONLY LIMITED SURFACE HEATING INTO
NORTHWESTERN SOUTH DAKOTA...SO IT APPEARS THAT THE BEST CHANCE FOR
SEVERE WILL HOLD OFF AT LEAST A FEW MORE HOURS UNTIL MID LEVEL
HEIGHT FALLS SPREAD INTO THE CENTRAL DAKOTAS ATOP BETTER
INSTABILITY AND MORE FAVORABLE SHEAR THAN THAT CURRENTLY OVER
SOUTHWESTERN NORTH DAKOTA. THIS IS SUPPORTED BY THE SHOWER THAT
FORMED AROUND 19 UTC AND FAILED TO GAIN STEAM NEAR HETTINGER.

USING VISIBLE SATELLITE AND RADAR...IT APPEARS THAT THE MOST
LIKELY SCENARIO IS FOR CONVECTION TO SLOWLY SPREAD INTO
SOUTHWESTERN NORTH DAKOTA OVER THE NEXT 5 HOURS...THEN MOVE
EASTWARD. THESE STORMS SHOULD THEN PROPAGATE EAST-NORTHEASTWARD
INTO SOUTHEASTERN NORTH DAKOTA...WITH THE BEST CHANCE FOR SEVERE
WEATHER BEING ALONG AND SOUTH OF I-94.

THEREAFTER...LINGERING SHOWERS AND THUNDERSTORMS ARE FORECAST
THROUGH THE WEEKEND AS BROAD LOW PRESSURE IS CUT OFF OVER THE
NORTHERN PLAINS.


.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 302 PM CDT SAT MAY 18 2013

THE MAIN FORECAST HIGHLIGHT OF THE EXTENDED PERIOD WILL BE
PRECIPITATION CHANCES AND AMOUNTS SUNDAY NIGHT THROUGH LATE
TUESDAY.

THERE IS STILL SOME DISAGREEMENT AMONGST THE 12Z DETERMINISTIC
MODELS REGARDING THE PLACEMENT AND MOVEMENT OF THE H500 CLOSED UPPER
LEVEL LOW OVER THE NORTHERN PLAINS. THE 12Z GFS KEEPS THE H500 LOW A
BIT FASTER AND FURTHER SOUTH THAN THE GEFS/ECWMF/GEM MONDAY AND
TUESDAY...WHICH INTRODUCES SOME DIFFERENCES IN THE TIMING AND
PLACEMENT OF PRECIPITATION ACROSS NORTH DAKOTA EARLY IN THE
EXTENDED. AS A CONSEQUENCE HAVE KEPT CHANCE/LIKELY POPS THROUGH MID
TUESDAY BEFORE BRINGING DOWN POPS FROM NORTHWEST TO SOUTHEAST AS THE
H500 LOW SLOWLY DRIFTS EAST AND AWAY FROM THE NORTHERN PLAINS. FOR
QPF...HAVE USED A BLEND OF MODEL GUIDANCE AS WELL AS THE WPC
GUIDANCE FOR AMOUNTS...WHICH HAS AN ADDITIONAL 1 TO 2 INCHES OF
RAINFALL FROM SUNDAY EVENING THROUGH LATE TUESDAY FOR LOCATIONS
SOUTH OF STATE HIGHWAY 2. TO THE NORTH (INCLUDING THE SOURIS RIVER
BASIN)...UP TO AN INCH OF ADDITIONAL RAINFALL IS POSSIBLE. AS SAID
WITH PREVIOUS FORECAST ISSUANCES...SIGNIFICANT RESPONSES ARE NOT
EXPECTED ON AREA RIVERS...BUT WILL BE WATCHING SMALLER CREEKS AND
STREAMS...AS WELL AS THE POTENTIAL FOR URBAN FLOODING.

BEYOND WEDNESDAY...THE ECWMF AND GFS SOLUTIONS DIVERGE WITH THE
PLACEMENT AND MOVEMENT OF THE NEXT WESTERN CONUS UPPER LEVEL
TROUGH...HOWEVER...THERE IS AGREEMENT THAT AN UPPER LEVEL RIDGE WILL
BEGIN TO BUILD OVER THE CENTRAL US AS THE AFOREMENTIONED CLOSED LOW
DEPARTS EAST. A SLOW WARMING TREND THROUGH THE END OF THIS COMING
WEEK AND CLEARING SKIES THURSDAY ARE EXPECTED ACROSS NORTH DAKOTA.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 302 PM CDT SAT MAY 18 2013

LOW STRATUS HAS BEEN VERY DIFFICULT TO FORECAST TODAY...BUT
SHOULD LIFT AT ALL SITES BY THIS EVENING...EVEN KMOT. SHOWERS AND
THUNDERSTORMS WILL CAUSE MVFR CONDITIONS AT MOST TAF SITES
TODAY...WITH BRIEF PERIODS OF IFR POSSIBLE IN STRONGER STORMS.
IFR/LIFR FOG AND LOW STRATUS WILL LIKELY RETURN AFTER MIDNIGHT
TONIGHT IN THE WAKE OF PRECIPITATION.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM/AVIATION...SCHECK
LONG TERM...LTH

000
FXUS63 KBIS 181824
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
124 PM CDT SAT MAY 18 2013

.UPDATE...
ISSUED AT 105 PM CDT SAT MAY 18 2013

THE DISCUSSION FROM THE PREVIOUS UPDATE REMAINS VALID AS THE MAIN
FOCUS IS STILL LOCATION AND TIMING OF CONVECTIVE INITIATION THIS
AFTERNOON.

THE ONLY NEW INFORMATION TO ADD IS THE PRESENCE OF LOW LEVEL
CONVERGENCE STRETCHING FROM DICKINSON TO BUFFALO SD. VISIBLE
SATELLITE INDICATES SOME AGITATED CUMULUS THERE...AND 18 UTC SPC
MESOANALYSIS INDICATES A MARKED INCREASE IN MIXED LAYER CAPE OVER
THE PAST HOUR. SHOULD THIS TREND CONTINUE...STRONGER STORMS MAY BE
REALIZED BY 4 PM CDT.

UPDATE ISSUED AT 1024 AM CDT SAT MAY 18 2013

THE TIMING AND LOCATION OF CONVECTIVE INITIATION IN THIS COMPLEX
SCENARIO IS THE MAIN FOCUS TODAY. PRECIPITATION CHANCES ALONG THE
MISSOURI RIVER HAVE GENERALLY BEEN LOWERED FOR THIS MORNING AND
EARLY AFTERNOON AS LOW LEVEL STRATUS WILL HELP TO STABILIZE THE
ATMOSPHERE UNTIL THE NEXT MID LEVEL SHORTWAVE ARRIVES THIS
AFTERNOON.

THE 12 AND 13 UTC HRRR HAVE PICKED UP ON THE CLEARING OVER
NORTHWESTERN SOUTH DAKOTA THIS MORNING...AND NOW INITIATES
CONVECTION THERE AND IN SOUTHWESTERN NORTH DAKOTA BY 21 UTC. 12
UTC GFS THERMODYNAMIC PROFILES SUPPORT THIS IDEA ALONG WITH THE 00
UTC ECMWF AS CAPE IS FORECAST TO EXCEED 1000 J/KG THERE.

THE CURRENT THINKING IS THAT CONVECTION WILL SPREAD GENERALLY
EAST-NORTHEASTWARD UNTIL MID/LATE AFTERNOON DESTABILIZATION AND
MIDDLE LEVEL HEIGHT FALLS FINALLY INITIATE ADDITIONAL CONVECTION
BETWEEN THE MISSOURI AND JAMES RIVERS ALONG THE DAKOTA BORDER.

UPDATE ISSUED AT 644 AM CDT SAT MAY 18 2013

UPDATE MAINLY FOR POP TRENDS TODAY. SHOWERS AND ISOLATED STORMS
HAVE PUSHED INTO THE FAR NORTHEAST EARLY THIS MORNING. RECENT RUNS
OF THE RAP HAVE A GOOD HANDLE ON NEAR TERM TRENDS...AND HAVE
REDUCED POPS THROUGH THE MORNING INTO EARLY AFTERNOON. STILL
EXPECTING THE FOCUS OF AFTERNOON CONVECTION ALONG A BOUNDARY TO
THE SOUTHEAST...WITH POTENTIAL FOR SOME SEVERE STORMS TO DEVELOP
BY MID AFTERNOON.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 430 AM CDT SAT MAY 18 2013

THE MAIN FOCUS IN THE SHORT TERM IS CONVECTIVE TRENDS AND
POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND TONIGHT. IN THE
NEAR TERM...THE 18/07Z RAP MODEL HAS A GOOD HANDLE ON THE LOCATION
OF THE CURRENT STORMS ACROSS THE NORTHEAST HALF OF THE FORECAST
AREA. STORMS SHOULD CONTINUE TO LIFT NORTH THROUGH THE MORNING
HOURS. AFTERNOON REDEVELOPMENT IS EXPECTED TO FOCUS ON THE TROUGH
EXTENDING ACROSS THE SOUTHEAST COUNTIES. ML CAPES AROUND 1500 TO
2000 J/KG ARE EXPECTED ALONG WITH DEEP LAYER SHEAR AT OR ABOVE 40
KTS...SUFFICIENT FOR SUPERCELL DEVELOPMENT WITH LARGE
HAIL/DAMAGING WIND THREAT. IN THE EXTREME SOUTHEAST...LOW
LCL`S...DECENT LOW LEVEL CAPE...AND A NARROW AREA OF FAVORABLE
0-1KM SHEAR SUGGEST THERE MAY ALSO BE A SEVERAL HOUR WINDOW OF
TORNADO THREAT THROUGH EARLY EVENING.

THE SOUTHEAST HALF OF THE FORECAST AREA LOOKS FAVORED FOR THE
HEAVIER RAINFALL AMOUNTS THROUGH TONIGHT. SIGNIFICANT RISES ON
MAINSTEM RIVERS ARE NOT EXPECTED...BUT WILL BE MONITORING FOR
LOCALIZED HEAVY RUNOFF AND ISOLATED SHORT TERM FLOODING DUE TO
EXTREME RAINFALL RATES OR MULTIPLE ROUNDS OF STORMS.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 430 AM CDT SAT MAY 18 2013

A LARGE CLOSED H5 LOW IS FORECAST TO DRIFT THROUGH THE REGION
SUNDAY THROUGH TUESDAY. THE THREAT FOR SEVERE WEATHER WILL
DIMINISH DURING THIS PERIOD...BUT MODERATE TO LOCALLY HEAVY RAINFALL
WILL PERSIST. ADDITIONAL RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE
POSSIBLE OVER THE WEEKEND THROUGH TUESDAY...WITH THE HIGHER TOTALS
TOWARD THE JAMES RIVER VALLEY. AGAIN...SIGNIFICANT RESPONSES ARE
NOT EXPECTED ON AREA RIVERS...BUT WILL BE WATCHING SMALLER CREEKS
AND STREAMS...AS WELL AS THE POTENTIAL FOR URBAN FLOODING. CLOUDS
AND RAIN WILL KEEP TEMPS DOWN IN THE 50S/LOWER 60S MONDAY AND
TUESDAY...BEFORE A WARMING TREND FROM MID TO LATE WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 105 PM CDT SAT MAY 18 2013

LOW STRATUS HAS BEEN VERY DIFFICULT TO FORECAST TODAY...BUT
SHOULD LIFT AT ALL SITES BY 20 UTC. SHOWERS AND THUNDERSTORMS WILL
CAUSE MVFR CONDITIONS AT MOST TAF SITES TODAY...WITH BRIEF PERIODS
OF IFR POSSIBLE IN STRONGER STORMS. IFR/LIFR FOG AND LOW STRATUS
WILL LIKELY RETURN AFTER MIDNIGHT TONIGHT IN THE WAKE OF
PRECIPITATION.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE/AVIATION...SCHECK
SHORT TERM/LONG TERM...RP KINNEY

000
FXUS63 KFGF 181819
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
119 PM CDT SAT MAY 18 2013

.UPDATE...
ISSUED AT 107 PM CDT SAT MAY 18 2013

AREA OF RAIN CONTINUES TO LIFT SLOWLY NORTH AND IS NOW ALONG THE
CANADIAN BORDER. NO MODEL REALLY HINTED AT THIS MUCH FROM 00Z AND
12Z RUNS. REST OF AREA DRY SOUTH OF HIGHWAY 2. SOME CLEARING IN SE
ND WORKING NORTH A BIT...AND IN THIS CLEAR AREA TEMPS IN THE 77 TO
80 DEGREE RANGE FROM TENNEY-WAHPETON TO FARGO-VALLEY CITY. DEW PTS
RANGE FROM UPPER 50S TO MID 60S IN THIS AREA. IT IS THIS AREA
WHICH WILL SEE CAPES 1500-2000 J/KG LATE TODAY...AND COULD SEE
STORM DEVELOPMENT. 12Z SPC WRF SHOWS SOME DEVELOPMENT FAR-DTL 22Z-
00Z WHEREAS HRRR SHOWS IT MORE AXN-BRD REGION. UPDATED POPS TO
SHOW THIS INCREASE IN POPS IN THE FAR SOUTH-SOUTHEAST AFTER 22Z.
DISC WITH WFO DLH/MPX WILL HOLD OFF ANY FFA FOR NOW HAS HEAVIEST
CONVECTION EARLIER THIS MORNING-LAST NIGHT WAS AXN-STC-BRD REGION
JUST TO OUR SOUTH.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 326 AM CDT SAT MAY 18 2013

FORECAST CHALLENGE THROUGH THE SHORT TERM WILL CONTINUE TO BE PCPN
CHANCES AS WELL AS SEVERE STORM AND HEAVY RAIN POTENTIAL. MODELS
IN FAIR AGREEMENT WITH MAIN FEATURES HOWEVER SUBTLE DIFFERENCES
EXIST WITH SURFACE LOW/BOUNDARY POSITIONS TODAY.

ARC OF WEAKENING CONVECTION LIFTING NE THROUGH FA AT 30KTS WILL
CONTINUE TO PROPAGATE NE THROUGH THE MORNING AND INTO EARLY
AFTERNOON. WILL ATTEMPT TO ADJUST/TIME POPS ACCORDINGLY.

TEMPERATURES WILL BE TRICKY AND DEPENDENT ON DEGREE OF CLOUD COVER
AND HOW FAR NORTH WARM FRONT GETS. WITH WARM COLUMN ANY BREAKS
WILL REALLY BOOST TEMPERATURES.

LATER TODAY AND INTO TONIGHT. SURFACE INVERTED TROUGH TO SHARPEN
ACROSS FA PROVIDING GOOD SOURCE OF LOW LEVEL CONVERGENCE. TOUGH TO
DETERMINE ANY SPECIFIC SHORT WAVE HOWEVER REGION COMES UNDER
ENTRANCE REGION OF MODEST JET STREAK WHICH WILL AID IN UPPER
SUPPORT. MODELS DIFFER ON LOCATION OF SURFACE LOW WHICH WILL RIDE
NORTHWARD ALONG TROUGH AS WELL AS POSITION OF WARM FRONTAL
BOUNDARY. MODELS INDICATING GOOD SURFACE MOISTURE FLUX WITH 60
DEWPOINTS SPREADING NORTHWARD THROUGH MOST OF FA. PRECIPITABLE H2O
VALUES INCREASE TO AROUND 1.5 BY EVENING. GREATEST INSTABILITY AND
CAPE ACROSS SOUTH HALF OF FA AND LOOKS TO BE THE FAVORED LOCATION
FOR SEVERE POTENTIAL. SOME CAPPING MAY INITIALLY DELAY CONVECTIVE
INITIATION DURING THE AFTERNOON. HEAVY RAIN POTENTIAL THERE BUT WITH
DIFFERENCES IN SURFACE LOW POSITION TO ENHANCE LOW LEVEL
CONVERGENCE NOT AS CLEAR CUT.

INVERTED TROUGH TO DRIFT EAST SUNDAY WHICH WILL PUT HEAVIER RAIN
THREAT INTO MN. TEMPERATURES TO BE QUITE A BIT COOLER ON BACK SIDE
OF INVERTED TROUGH.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 326 AM CDT SAT MAY 18 2013

CUT OFF LOW TAKES OVER AND DRIFTS ACROSS E SD INTO S MN TO START WORK
WEEK FOR CONTINUED MODERATE RAIN POTENTIAL AND COOLER TEMPERATURES.

TUESDAY-FRIDAY...THE UPPER LOW WILL SLOWLY SHIFT EASTWARD FROM THE
CENTRAL/NORTHERN PLAINS INTO THE GREAT LAKES DURING THIS PERIOD. THE
00Z GFS/12Z ECMWF BEGIN TO SHIFT SHOWER ACTIVITY SOUTH AND EAST ON
WEDNESDAY...WITH THE GEM SLOWER IN ENDING THE PRECIP. WILL CONTINUE
TO MENTION POPS ACROSS THE SOUTHEAST THROUGH WEDNESDAY NIGHT. SFC
HIGH PRESSURE IS EXPECTED TO BUILD ACROSS THE AREA TOWARDS THE END
OF THE WEEK AS MID/UPPER LEVEL RIDGING DEVELOPS ACROSS THE PLAINS.
BELOW NORMAL TEMPS WILL MODERATE BACK TO NEAR NORMAL BY LATE NEXT
WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 107 PM CDT SAT MAY 18 2013

ACROSS NERN ND AND NRWN MN...AREAS OF IFR TO LIFR CIGS AND VSBYS
ALG AND NORTH OF U.S. HWY 2 WILL SLOWLY LIFT AND SHIFT NORTHWARD
THIS AFTERNOON...WITH SCT MVFR CIGS LIKELY TO PERSIST INTO THE
EVENING. SCT TSTMS ARE EXPECTED TO DEVELOP FROM LATE AFTERNOON
INTO THE EARLY EVENING...BECOMING MORE NUMEROUS INTO THE LATE
EVENING. ACROSS SERN ND INTO WCNTRL MN...AREAS OF LIFR TO IFR CIGS
AND VSBYS ALG AND EAST OF AN AXN-BJI LINE WILL SLOWLY LIFT AND
SHIFT NORTHEASTWARD THROUGH THIS AFTERNOON...WITH SCT MVFR CIGS
LIKELY TO PERSIST INTO THE EVENING. OTHERWISE...FAIR SKIES OVER
THE SOUTHERN RRV WILL ALLOW FOR INCREASED SFC HEATING AND THE
DEVELOPMENT OF SCT TSTMS /WITH ISOLD LARGE HAIL/ FROM MID
AFTERNOON INTO THE EARLY EVENING...BECOMING MORE NUMEROUS INTO
MIDNIGHT.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...RIDDLE
SHORT TERM...VOELKER
LONG TERM...MAKOWSKI/VOELKER
AVIATION...GUST

000
FXUS63 KFGF 181552
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
1052 AM CDT SAT MAY 18 2013

.UPDATE...
ISSUED AT 1049 AM CDT SAT MAY 18 2013

LATE MORNING UPDATE WAS TO GO DRY THROUGH LATE AFTN IN SE ND INTO
WCNTRL MN. TEMPS SOMEWHAT OF AN ISSUE AND LOWERED A BIT ESP NRN
ZONES WHERE LOW 60S IN LANGDON-CANDO MAY BE ALL THAT CAN BE DONE.
KEPT HIGH POPS FAR NRN FCST AREA IN NE ND/NW MN WITH SHOWERS
MOVING THRU. STILL THINKING LOWER 80S OR SO FAR SE ND...BUT
DEPENDS ON AMOUNT OF SUN. LATEST HRRR/RAP ALL INDICATE MAIN WARM
FRONT AND CONVECTION DEVELOPING IN NRN SD INTO CNTRL MN 22Z-00Z
PERIOD AND THEN MAYBE LIFTING NORTH INTO SE ND.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 326 AM CDT SAT MAY 18 2013

FORECAST CHALLENGE THROUGH THE SHORT TERM WILL CONTINUE TO BE PCPN
CHANCES AS WELL AS SEVERE STORM AND HEAVY RAIN POTENTIAL. MODELS
IN FAIR AGREEMENT WITH MAIN FEATURES HOWEVER SUBTLE DIFFERENCES
EXIST WITH SURFACE LOW/BOUNDARY POSITIONS TODAY.

ARC OF WEAKENING CONVECTION LIFTING NE THROUGH FA AT 30KTS WILL
CONTINUE TO PROPAGATE NE THROUGH THE MORNING AND INTO EARLY
AFTERNOON. WILL ATTEMPT TO ADJUST/TIME POPS ACCORDINGLY.

TEMPERATURES WILL BE TRICKY AND DEPENDENT ON DEGREE OF CLOUD COVER
AND HOW FAR NORTH WARM FRONT GETS. WITH WARM COLUMN ANY BREAKS
WILL REALLY BOOST TEMPERATURES.

LATER TODAY AND INTO TONIGHT. SURFACE INVERTED TROUGH TO SHARPEN
ACROSS FA PROVIDING GOOD SOURCE OF LOW LEVEL CONVERGENCE. TOUGH TO
DETERMINE ANY SPECIFIC SHORT WAVE HOWEVER REGION COMES UNDER
ENTRANCE REGION OF MODEST JET STREAK WHICH WILL AID IN UPPER
SUPPORT. MODELS DIFFER ON LOCATION OF SURFACE LOW WHICH WILL RIDE
NORTHWARD ALONG TROUGH AS WELL AS POSITION OF WARM FRONTAL
BOUNDARY. MODELS INDICATING GOOD SURFACE MOISTURE FLUX WITH 60
DEWPOINTS SPREADING NORTHWARD THROUGH MOST OF FA. PRECIPITABLE H2O
VALUES INCREASE TO AROUND 1.5 BY EVENING. GREATEST INSTABILITY AND
CAPE ACROSS SOUTH HALF OF FA AND LOOKS TO BE THE FAVORED LOCATION
FOR SEVERE POTENTIAL. SOME CAPPING MAY INITIALLY DELAY CONVECTIVE
INITIATION DURING THE AFTERNOON. HEAVY RAIN POTENTIAL THERE BUT WITH
DIFFERENCES IN SURFACE LOW POSITION TO ENHANCE LOW LEVEL
CONVERGENCE NOT AS CLEAR CUT.

INVERTED TROUGH TO DRIFT EAST SUNDAY WHICH WILL PUT HEAVIER RAIN
THREAT INTO MN. TEMPERATURES TO BE QUITE A BIT COOLER ON BACK SIDE
OF INVERTED TROUGH.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 326 AM CDT SAT MAY 18 2013

CUT OFF LOW TAKES OVER AND DRIFTS ACROSS E SD INTO S MN TO START WORK
WEEK FOR CONTINUED MODERATE RAIN POTENTIAL AND COOLER TEMPERATURES.

TUESDAY-FRIDAY...THE UPPER LOW WILL SLOWLY SHIFT EASTWARD FROM THE
CENTRAL/NORTHERN PLAINS INTO THE GREAT LAKES DURING THIS PERIOD. THE
00Z GFS/12Z ECMWF BEGIN TO SHIFT SHOWER ACTIVITY SOUTH AND EAST ON
WEDNESDAY...WITH THE GEM SLOWER IN ENDING THE PRECIP. WILL CONTINUE
TO MENTION POPS ACROSS THE SOUTHEAST THROUGH WEDNESDAY NIGHT. SFC
HIGH PRESSURE IS EXPECTED TO BUILD ACROSS THE AREA TOWARDS THE END
OF THE WEEK AS MID/UPPER LEVEL RIDGING DEVELOPS ACROSS THE PLAINS.
BELOW NORMAL TEMPS WILL MODERATE BACK TO NEAR NORMAL BY LATE NEXT
WEEK.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 650 AM CDT SAT MAY 18 2013

WITH SHOWERS IN THE VCNTY CIGS VARY GREATLY. CIGS GENERALLY BOUNCING
BETWEEN MVFR/VFR WITH MOSTLY VFR CIGS. THERE IS HOWEVER SOME
LOCALIZED IFR CIGS IN BR BUT NOT LIMITED TO WITHIN RAIN BAND.
EXPECT CONDITION TO PERSIST THROUGH THE MORNING AS SHRA LIFT
NORTHWARD. COULD SEE MORE VFR CONDITIONS THIS AFTERNOON WITH TSRA
POSSIBLE LATE AFTERNOON.


&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...RIDDLE
SHORT TERM...VOELKER
LONG TERM...MAKOWSKI/VOELKER
AVIATION...VOELKER

000
FXUS63 KBIS 181546
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
1046 AM CDT SAT MAY 18 2013

.UPDATE...
ISSUED AT 1024 AM CDT SAT MAY 18 2013

THE TIMING AND LOCATION OF CONVECTIVE INITIATION IN THIS COMPLEX
SCENARIO IS THE MAIN FOCUS TODAY. PRECIPITATION CHANCES ALONG THE
MISSOURI RIVER HAVE GENERALLY BEEN LOWERED FOR THIS MORNING AND
EARLY AFTERNOON AS LOW LEVEL STRATUS WILL HELP TO STABILIZE THE
ATMOSPHERE UNTIL THE NEXT MID LEVEL SHORTWAVE ARRIVES THIS
AFTERNOON.

THE 12 AND 13 UTC HRRR HAVE PICKED UP ON THE CLEARING OVER
NORTHWESTERN SOUTH DAKOTA THIS MORNING...AND NOW INITIATES
CONVECTION THERE AND IN SOUTHWESTERN NORTH DAKOTA BY 21 UTC. 12
UTC GFS THERMODYNAMIC PROFILES SUPPORT THIS IDEA ALONG WITH THE 00
UTC ECMWF AS CAPE IS FORECAST TO EXCEED 1000 J/KG THERE.

THE CURRENT THINKING IS THAT CONVECTION WILL SPREAD GENERALLY
EAST-NORTHEASTWARD UNTIL MID/LATE AFTERNOON DESTABILIZATION AND
MIDDLE LEVEL HEIGHT FALLS FINALLY INITIATE ADDITIONAL CONVECTION
BETWEEN THE MISSOURI AND JAMES RIVERS ALONG THE DAKOTA BORDER.

UPDATE ISSUED AT 644 AM CDT SAT MAY 18 2013

UPDATE MAINLY FOR POP TRENDS TODAY. SHOWERS AND ISOLATED STORMS
HAVE PUSHED INTO THE FAR NORTHEAST EARLY THIS MORNING. RECENT RUNS
OF THE RAP HAVE A GOOD HANDLE ON NEAR TERM TRENDS...AND HAVE
REDUCED POPS THROUGH THE MORNING INTO EARLY AFTERNOON. STILL
EXPECTING THE FOCUS OF AFTERNOON CONVECTION ALONG A BOUNDARY TO
THE SOUTHEAST...WITH POTENTIAL FOR SOME SEVERE STORMS TO DEVELOP
BY MID AFTERNOON.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 430 AM CDT SAT MAY 18 2013

THE MAIN FOCUS IN THE SHORT TERM IS CONVECTIVE TRENDS AND
POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND TONIGHT. IN THE
NEAR TERM...THE 18/07Z RAP MODEL HAS A GOOD HANDLE ON THE LOCATION
OF THE CURRENT STORMS ACROSS THE NORTHEAST HALF OF THE FORECAST
AREA. STORMS SHOULD CONTINUE TO LIFT NORTH THROUGH THE MORNING
HOURS. AFTERNOON REDEVELOPMENT IS EXPECTED TO FOCUS ON THE TROUGH
EXTENDING ACROSS THE SOUTHEAST COUNTIES. ML CAPES AROUND 1500 TO
2000 J/KG ARE EXPECTED ALONG WITH DEEP LAYER SHEAR AT OR ABOVE 40
KTS...SUFFICIENT FOR SUPERCELL DEVELOPMENT WITH LARGE
HAIL/DAMAGING WIND THREAT. IN THE EXTREME SOUTHEAST...LOW
LCL`S...DECENT LOW LEVEL CAPE...AND A NARROW AREA OF FAVORABLE
0-1KM SHEAR SUGGEST THERE MAY ALSO BE A SEVERAL HOUR WINDOW OF
TORNADO THREAT THROUGH EARLY EVENING.

THE SOUTHEAST HALF OF THE FORECAST AREA LOOKS FAVORED FOR THE
HEAVIER RAINFALL AMOUNTS THROUGH TONIGHT. SIGNIFICANT RISES ON
MAINSTEM RIVERS ARE NOT EXPECTED...BUT WILL BE MONITORING FOR
LOCALIZED HEAVY RUNOFF AND ISOLATED SHORT TERM FLOODING DUE TO
EXTREME RAINFALL RATES OR MULTIPLE ROUNDS OF STORMS.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 430 AM CDT SAT MAY 18 2013

A LARGE CLOSED H5 LOW IS FORECAST TO DRIFT THROUGH THE REGION
SUNDAY THROUGH TUESDAY. THE THREAT FOR SEVERE WEATHER WILL
DIMINISH DURING THIS PERIOD...BUT MODERATE TO LOCALLY HEAVY RAINFALL
WILL PERSIST. ADDITIONAL RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE
POSSIBLE OVER THE WEEKEND THROUGH TUESDAY...WITH THE HIGHER TOTALS
TOWARD THE JAMES RIVER VALLEY. AGAIN...SIGNIFICANT RESPONSES ARE
NOT EXPECTED ON AREA RIVERS...BUT WILL BE WATCHING SMALLER CREEKS
AND STREAMS...AS WELL AS THE POTENTIAL FOR URBAN FLOODING. CLOUDS
AND RAIN WILL KEEP TEMPS DOWN IN THE 50S/LOWER 60S MONDAY AND
TUESDAY...BEFORE A WARMING TREND FROM MID TO LATE WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1024 AM CDT SAT MAY 18 2013

LOW STRATUS HAS BEEN VERY DIFFICULT TO FORECAST THIS MORNING...BUT
SHOULD IMPROVE BY 18 UTC. SHOWERS AND THUNDERSTORMS WILL CAUSE
MVFR CONDITIONS AT MOST TAF SITES TODAY...WITH BRIEF PERIODS OF
IFR POSSIBLE IN STRONGER STORMS. FOG AND LOW STRATUS WILL LIKELY
RETURN AFTER MIDNIGHT TONIGHT IN THE WAKE OF PRECIPITATION.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE/AVIATION...SCHECK
SHORT TERM/LONG TERM...RP KINNEY

000
FXUS63 KFGF 181157
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
657 AM CDT SAT MAY 18 2013

.UPDATE...
ISSUED AT 650 AM CDT SAT MAY 18 2013

BAND OF MAINLY SHRA SLOWLY LIFTING NORTH. ADJUSTED POPS BASED ON
SLOWER MOVEMENT AND WENT PRIMARILY SHRA WITH MAYBE SOME ISOLD T.
MAINTAINED CHANCE POPS THIS AFTERNOON BUT CAPPING MAY LIMIT
CONVECTIVE DEVELOPMENT UNTIL LATE AFTERNOON. KEEPING TEMPERATURES
AS IS FOR NOW.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 326 AM CDT SAT MAY 18 2013

FORECAST CHALLENGE THROUGH THE SHORT TERM WILL CONTINUE TO BE PCPN
CHANCES AS WELL AS SEVERE STORM AND HEAVY RAIN POTENTIAL. MODELS
IN FAIR AGREEMENT WITH MAIN FEATURES HOWEVER SUBTLE DIFFERENCES
EXIST WITH SURFACE LOW/BOUNDARY POSITIONS TODAY.

ARC OF WEAKENING CONVECTION LIFTING NE THROUGH FA AT 30KTS WILL
CONTINUE TO PROPAGATE NE THROUGH THE MORNING AND INTO EARLY
AFTERNOON. WILL ATTEMPT TO ADJUST/TIME POPS ACCORDINGLY.

TEMPERATURES WILL BE TRICKY AND DEPENDENT ON DEGREE OF CLOUD COVER
AND HOW FAR NORTH WARM FRONT GETS. WITH WARM COLUMN ANY BREAKS
WILL REALLY BOOST TEMPERATURES.

LATER TODAY AND INTO TONIGHT. SURFACE INVERTED TROUGH TO SHARPEN
ACROSS FA PROVIDING GOOD SOURCE OF LOW LEVEL CONVERGENCE. TOUGH TO
DETERMINE ANY SPECIFIC SHORT WAVE HOWEVER REGION COMES UNDER
ENTRANCE REGION OF MODEST JET STREAK WHICH WILL AID IN UPPER
SUPPORT. MODELS DIFFER ON LOCATION OF SURFACE LOW WHICH WILL RIDE
NORTHWARD ALONG TROUGH AS WELL AS POSITION OF WARM FRONTAL
BOUNDARY. MODELS INDICATING GOOD SURFACE MOISTURE FLUX WITH 60
DEWPOINTS SPREADING NORTHWARD THROUGH MOST OF FA. PRECIPITABLE H2O
VALUES INCREASE TO AROUND 1.5 BY EVENING. GREATEST INSTABILITY AND
CAPE ACROSS SOUTH HALF OF FA AND LOOKS TO BE THE FAVORED LOCATION
FOR SEVERE POTENTIAL. SOME CAPPING MAY INITIALLY DELAY CONVECTIVE
INITIATION DURING THE AFTERNOON. HEAVY RAIN POTENTIAL THERE BUT WITH
DIFFERENCES IN SURFACE LOW POSITION TO ENHANCE LOW LEVEL
CONVERGENCE NOT AS CLEAR CUT.

INVERTED TROUGH TO DRIFT EAST SUNDAY WHICH WILL PUT HEAVIER RAIN
THREAT INTO MN. TEMPERATURES TO BE QUITE A BIT COOLER ON BACK SIDE
OF INVERTED TROUGH.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 326 AM CDT SAT MAY 18 2013

CUT OFF LOW TAKES OVER AND DRIFTS ACROSS E SD INTO S MN TO START WORK
WEEK FOR CONTINUED MODERATE RAIN POTENTIAL AND COOLER TEMPERATURES.

TUESDAY-FRIDAY...THE UPPER LOW WILL SLOWLY SHIFT EASTWARD FROM THE
CENTRAL/NORTHERN PLAINS INTO THE GREAT LAKES DURING THIS PERIOD. THE
00Z GFS/12Z ECMWF BEGIN TO SHIFT SHOWER ACTIVITY SOUTH AND EAST ON
WEDNESDAY...WITH THE GEM SLOWER IN ENDING THE PRECIP. WILL CONTINUE
TO MENTION POPS ACROSS THE SOUTHEAST THROUGH WEDNESDAY NIGHT. SFC
HIGH PRESSURE IS EXPECTED TO BUILD ACROSS THE AREA TOWARDS THE END
OF THE WEEK AS MID/UPPER LEVEL RIDGING DEVELOPS ACROSS THE PLAINS.
BELOW NORMAL TEMPS WILL MODERATE BACK TO NEAR NORMAL BY LATE NEXT
WEEK.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 650 AM CDT SAT MAY 18 2013

WITH SHOWERS IN THE VCNTY CIGS VARY GREATLY. CIGS GENERALLY BOUNCING
BETWEEN MVFR/VFR WITH MOSTLY VFR CIGS. THERE IS HOWEVER SOME
LOCALIZED IFR CIGS IN BR BUT NOT LIMITED TO WITHIN RAIN BAND.
EXPECT CONDITION TO PERSIST THROUGH THE MORNING AS SHRA LIFT
NORTHWARD. COULD SEE MORE VFR CONDITIONS THIS AFTERNOON WITH TSRA
POSSIBLE LATE AFTERNOON.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...VOELKER
SHORT TERM...VOELKER
LONG TERM...MAKOWSKI/VOELKER
AVIATION...VOELKER

000
FXUS63 KBIS 181144
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
644 AM CDT SAT MAY 18 2013

.UPDATE...
ISSUED AT 644 AM CDT SAT MAY 18 2013

UPDATE MAINLY FOR POP TRENDS TODAY. SHOWERS AND ISOLATED STORMS
HAVE PUSHED INTO THE FAR NORTHEAST EARLY THIS MORNING. RECENT RUNS
OF THE RAP HAVE A GOOD HANDLE ON NEAR TERM TRENDS...AND HAVE
REDUCED POPS THROUGH THE MORNING INTO EARLY AFTERNOON. STILL
EXPECTING THE FOCUS OF AFTERNOON CONVECTION ALONG A BOUNDARY TO
THE SOUTHEAST...WITH POTENTIAL FOR SOME SEVERE STORMS TO DEVELOP
BY MID AFTERNOON.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 430 AM CDT SAT MAY 18 2013

THE MAIN FOCUS IN THE SHORT TERM IS CONVECTIVE TRENDS AND
POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND TONIGHT. IN THE
NEAR TERM...THE 18/07Z RAP MODEL HAS A GOOD HANDLE ON THE LOCATION
OF THE CURRENT STORMS ACROSS THE NORTHEAST HALF OF THE FORECAST
AREA. STORMS SHOULD CONTINUE TO LIFT NORTH THROUGH THE MORNING
HOURS. AFTERNOON REDEVELOPMENT IS EXPECTED TO FOCUS ON THE TROUGH
EXTENDING ACROSS THE SOUTHEAST COUNTIES. ML CAPES AROUND 1500 TO
2000 J/KG ARE EXPECTED ALONG WITH DEEP LAYER SHEAR AT OR ABOVE 40
KTS...SUFFICIENT FOR SUPERCELL DEVELOPMENT WITH LARGE
HAIL/DAMAGING WIND THREAT. IN THE EXTREME SOUTHEAST...LOW
LCL`S...DECENT LOW LEVEL CAPE...AND A NARROW AREA OF FAVORABLE
0-1KM SHEAR SUGGEST THERE MAY ALSO BE A SEVERAL HOUR WINDOW OF
TORNADO THREAT THROUGH EARLY EVENING.

THE SOUTHEAST HALF OF THE FORECAST AREA LOOKS FAVORED FOR THE
HEAVIER RAINFALL AMOUNTS THROUGH TONIGHT. SIGNIFICANT RISES ON
MAINSTEM RIVERS ARE NOT EXPECTED...BUT WILL BE MONITORING FOR
LOCALIZED HEAVY RUNOFF AND ISOLATED SHORT TERM FLOODING DUE TO
EXTREME RAINFALL RATES OR MULTIPLE ROUNDS OF STORMS.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 430 AM CDT SAT MAY 18 2013

A LARGE CLOSED H5 LOW IS FORECAST TO DRIFT THROUGH THE REGION
SUNDAY THROUGH TUESDAY. THE THREAT FOR SEVERE WEATHER WILL
DIMINISH DURING THIS PERIOD...BUT MODERATE TO LOCALLY HEAVY RAINFALL
WILL PERSIST. ADDITIONAL RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE
POSSIBLE OVER THE WEEKEND THROUGH TUESDAY...WITH THE HIGHER TOTALS
TOWARD THE JAMES RIVER VALLEY. AGAIN...SIGNIFICANT RESPONSES ARE
NOT EXPECTED ON AREA RIVERS...BUT WILL BE WATCHING SMALLER CREEKS
AND STREAMS...AS WELL AS THE POTENTIAL FOR URBAN FLOODING. CLOUDS
AND RAIN WILL KEEP TEMPS DOWN IN THE 50S/LOWER 60S MONDAY AND
TUESDAY...BEFORE A WARMING TREND FROM MID TO LATE WEEK.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 430 AM CDT SAT MAY 18 2013

AREA OF SHOWERS AND SCATTERED THUNDERSTORMS CONTINUE TO PUSH
NORTH AND EAST AS A MID LEVEL DISTURBANCE LIFTS NORTHEAST ACROSS
CENTRAL NORTH DAKOTA EARLY THIS MORNING. PRECIPITATION HAS ENDED
AT KBIS-KDIK-KISN...AND WILL END BY 15Z FOR KMOT-KJMS. HIGH LOW
LEVEL MOISTURE WILL RESULT IN AREAS OF FOG AND POSSIBLE VLIFR
STRATUS THIS MORNING AT MOST IF NOT ALL TERMINALS. WHILE THE
STRATUS AND FOG SHOULD LIFT BY MID MORNING...IT MAY LINGER AT KMOT
INTO SATURDAY AFTERNOON...THEN DEVELOP OVER ALL TERMINALS ONCE
AGAIN SATURDAY NIGHT.

SHOWERS AND THUNDERSTORMS WILL REDEVELOP AFTER 18Z SATURDAY
AFTERNOON...DEVELOPING NORTH AND EAST INTO SATURDAY NIGHT.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE/SHORT TERM/LONG TERM...RP KINNEY
AVIATION...NH

000
FXUS63 KBIS 180930
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
430 AM CDT SAT MAY 18 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 430 AM CDT SAT MAY 18 2013

THE MAIN FOCUS IN THE SHORT TERM IS CONVECTIVE TRENDS AND
POTENTIAL FOR SEVERE WEATHER THIS AFTERNOON AND TONIGHT. IN THE
NEAR TERM...THE 18/07Z RAP MODEL HAS A GOOD HANDLE ON THE LOCATION
OF THE CURRENT STORMS ACROSS THE NORTHEAST HALF OF THE FORECAST
AREA. STORMS SHOULD CONTINUE TO LIFT NORTH THROUGH THE MORNING
HOURS. AFTERNOON REDEVELOPMENT IS EXPECTED TO FOCUS ON THE TROUGH
EXTENDING ACROSS THE SOUTHEAST COUNTIES. ML CAPES AROUND 1500 TO
2000 J/KG ARE EXPECTED ALONG WITH DEEP LAYER SHEAR AT OR ABOVE 40
KTS...SUFFICIENT FOR SUPERCELL DEVELOPMENT WITH LARGE
HAIL/DAMAGING WIND THREAT. IN THE EXTREME SOUTHEAST...LOW
LCL`S...DECENT LOW LEVEL CAPE...AND A NARROW AREA OF FAVORABLE
0-1KM SHEAR SUGGEST THERE MAY ALSO BE A SEVERAL HOUR WINDOW OF
TORNADO THREAT THROUGH EARLY EVENING.

THE SOUTHEAST HALF OF THE FORECAST AREA LOOKS FAVORED FOR THE
HEAVIER RAINFALL AMOUNTS THROUGH TONIGHT. SIGNIFICANT RISES ON
MAINSTEM RIVERS ARE NOT EXPECTED...BUT WILL BE MONITORING FOR
LOCALIZED HEAVY RUNOFF AND ISOLATED SHORT TERM FLOODING DUE TO
EXTREME RAINFALL RATES OR MULTIPLE ROUNDS OF STORMS.


.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 430 AM CDT SAT MAY 18 2013

A LARGE CLOSED H5 LOW IS FORECAST TO DRIFT THROUGH THE REGION
SUNDAY THROUGH TUESDAY. THE THREAT FOR SEVERE WEATHER WILL
DIMINISH DURING THIS PERIOD...BUT MODERATE TO LOCALLY HEAVY RAINFALL
WILL PERSIST. ADDITIONAL RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE
POSSIBLE OVER THE WEEKEND THROUGH TUESDAY...WITH THE HIGHER TOTALS
TOWARD THE JAMES RIVER VALLEY. AGAIN...SIGNIFICANT RESPONSES ARE
NOT EXPECTED ON AREA RIVERS...BUT WILL BE WATCHING SMALLER CREEKS
AND STREAMS...AS WELL AS THE POTENTIAL FOR URBAN FLOODING. CLOUDS
AND RAIN WILL KEEP TEMPS DOWN IN THE 50S/LOWER 60S MONDAY AND
TUESDAY...BEFORE A WARMING TREND FROM MID TO LATE WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 430 AM CDT SAT MAY 18 2013

AREA OF SHOWERS AND SCATTERED THUNDERSTORMS CONTINUE TO PUSH
NORTH AND EAST AS A MID LEVEL DISTURBANCE LIFTS NORTHEAST ACROSS
CENTRAL NORTH DAKOTA EARLY THIS MORNING. PRECIPITATION HAS ENDED
AT KBIS-KDIK-KISN...AND WILL END BY 15Z FOR KMOT-KJMS. HIGH LOW
LEVEL MOISTURE WILL RESULT IN AREAS OF FOG AND POSSIBLE VLIFR
STRATUS THIS MORNING AT MOST IF NOT ALL TERMINALS. WHILE THE
STRATUS AND FOG SHOULD LIFT BY MID MORNING...IT MAY LINGER AT KMOT
INTO SATURDAY AFTERNOON...THEN DEVELOP OVER ALL TERMINALS ONCE
AGAIN SATURDAY NIGHT.

SHOWERS AND THUNDERSTORMS WILL REDEVELOP AFTER 18Z SATURDAY
AFTERNOON...DEVELOPING NORTH AND EAST INTO SATURDAY NIGHT.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SHORT TERM/LONG TERM...RP KINNEY
AVIATION...NH

000
FXUS63 KFGF 180831
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
331 AM CDT SAT MAY 18 2013

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 326 AM CDT SAT MAY 18 2013

FORECAST CHALLENGE THROUGH THE SHORT TERM WILL CONTINUE TO BE PCPN
CHANCES AS WELL AS SEVERE STORM AND HEAVY RAIN POTENTIAL. MODELS
IN FAIR AGREEMENT WITH MAIN FEATURES HOWEVER SUBTLE DIFFERENCES
EXIST WITH SURFACE LOW/BOUNDARY POSITIONS TODAY.

ARC OF WEAKENING CONVECTION LIFTING NE THROUGH FA AT 30KTS WILL
CONTINUE TO PROPAGATE NE THROUGH THE MORNING AND INTO EARLY
AFTERNOON. WILL ATTEMPT TO ADJUST/TIME POPS ACCORDINGLY.

TEMPERATURES WILL BE TRICKY AND DEPENDENT ON DEGREE OF CLOUD COVER
AND HOW FAR NORTH WARM FRONT GETS. WITH WARM COLUMN ANY BREAKS
WILL REALLY BOOST TEMPERATURES.

LATER TODAY AND INTO TONIGHT. SURFACE INVERTED TROUGH TO SHARPEN
ACROSS FA PROVIDING GOOD SOURCE OF LOW LEVEL CONVERGENCE. TOUGH TO
DETERMINE ANY SPECIFIC SHORT WAVE HOWEVER REGION COMES UNDER
ENTRANCE REGION OF MODEST JET STREAK WHICH WILL AID IN UPPER
SUPPORT. MODELS DIFFER ON LOCATION OF SURFACE LOW WHICH WILL RIDE
NORTHWARD ALONG TROUGH AS WELL AS POSITION OF WARM FRONTAL
BOUNDARY. MODELS INDICATING GOOD SURFACE MOISTURE FLUX WITH 60
DEWPOINTS SPREADING NORTHWARD THROUGH MOST OF FA. PRECIPITABLE H2O
VALUES INCREASE TO AROUND 1.5 BY EVENING. GREATEST INSTABILITY AND
CAPE ACROSS SOUTH HALF OF FA AND LOOKS TO BE THE FAVORED LOCATION
FOR SEVERE POTENTIAL. SOME CAPPING MAY INITIALLY DELAY CONVECTIVE
INITIATION DURING THE AFTERNOON. HEAVY RAIN POTENTIAL THERE BUT WITH
DIFFERENCES IN SURFACE LOW POSITION TO ENHANCE LOW LEVEL
CONVERGENCE NOT AS CLEAR CUT.

INVERTED TROUGH TO DRIFT EAST SUNDAY WHICH WILL PUT HEAVIER RAIN
THREAT INTO MN. TEMPERATURES TO BE QUITE A BIT COOLER ON BACK SIDE
OF INVERTED TROUGH.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 326 AM CDT SAT MAY 18 2013

CUT OFF LOW TAKES OVER AND DRIFTS ACROSS E SD INTO S MN TO START WORK
WEEK FOR CONTINUED MODERATE RAIN POTENTIAL AND COOLER TEMPERATURES.

TUESDAY-FRIDAY...THE UPPER LOW WILL SLOWLY SHIFT EASTWARD FROM THE
CENTRAL/NORTHERN PLAINS INTO THE GREAT LAKES DURING THIS PERIOD. THE
00Z GFS/12Z ECMWF BEGIN TO SHIFT SHOWER ACTIVITY SOUTH AND EAST ON
WEDNESDAY...WITH THE GEM SLOWER IN ENDING THE PRECIP. WILL CONTINUE
TO MENTION POPS ACROSS THE SOUTHEAST THROUGH WEDNESDAY NIGHT. SFC
HIGH PRESSURE IS EXPECTED TO BUILD ACROSS THE AREA TOWARDS THE END
OF THE WEEK AS MID/UPPER LEVEL RIDGING DEVELOPS ACROSS THE PLAINS.
BELOW NORMAL TEMPS WILL MODERATE BACK TO NEAR NORMAL BY LATE NEXT
WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1141 PM CDT FRI MAY 17 2013

CEILINGS HAVE GONE DOWN TO MVFR AT KFAR AND THE LOWER CONDITIONS
WILL CONTINUE TO SPREAD NORTHWARD THROUGH MUCH OF THE NIGHT.
WEAKENING STORMS WILL ENTER THE FORECAST AREA AFTER
MIDNIGHT...MOVING INTO KFAR AREA AROUND 07-08Z WITH SOME THUNDER
REMAINING AND CONTINUING NORTH AS MOSTLY SHOWERS LATER ON THIS
MORNING. THINK THERE SHOULD BE SOME IMPROVEMENT TO VFR CONDITIONS
ACROSS MOST AREAS DURING THE AFTERNOON ALTHOUGH WILL HAVE TO WATCH
THE NORTHERN SITES WHICH MAY BE ON THE NORTH SIDE OF A WARM FRONT
AND STAY SOCKED IN. KFAR HAS THE BEST CHANCE OF SEEING SOME
CONVECTIVE REDEVELOPMENT TOWARDS THE END OF THE PERIOD.


&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

SHORT TERM...VOELKER
LONG TERM...MAKOWSKI/VOELKER
AVIATION...JR

000
FXUS63 KBIS 180619
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
119 AM CDT SAT MAY 18 2013

.UPDATE...
ISSUED AT 114 AM CDT SAT MAY 18 2013

UPDATE MAINLY TO REFINE POPS FOR HIGHER COVERAGE OF STORMS
OVERNIGHT OVER MOST OF THE FORECAST AREA. THE NORTHERN HALF SHOULD
BECOME THE FOCUS FOR THE BULK OF THE SHOWERS AND STORMS TOWARD
DAYBREAK. CONVECTIVE INTENSITY HAS BEEN DOWNWARD OVER THE PAST
COUPLE OF HOURS...AND THE THREAT FOR ADDITIONAL SEVERE STORMS IS
LOW. HOWEVER...STRONGER STORMS COULD DUMP A QUICK INCH OF RAIN AND
CAUSE PONDING WATER.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 258 PM CDT FRI MAY 17 2013

THE MAIN SHORT TERM FOCUS IS PRECIPITATION THROUGH SATURDAY.

PRECIPITATION CHANCES HAVE GENERALLY BEEN LOWERED FROM CONTINUITY
BASED ON MODEL CONSENSUS AND COORDINATION WITH SURROUNDING
OFFICES. THEY NOW REFLECT THE BEST CHANCES FOR SHOWERS AND
THUNDERSTORMS. UNFORTUNATELY...THE AVAILABLE 12 UTC THROUGH 18 UTC
GUIDANCE DISAGREES WITH TIMING AND COVERAGE ACROSS MUCH OF THE
STATE FOR THIS AFTERNOON AND TONIGHT...BUT THERE IS GENERAL
AGREEMENT THAT AN AREA OF CONVECTION WILL DEVELOP OVER
SOUTHEASTERN MONTANA THIS AFTERNOON AND MOVE EAST-NORTHEAST.

WATER VAPOR SATELLITE IMAGERY INDICATES THE LEADING EDGE OF THE
NEXT MID LEVEL SHORTWAVE WILL NOSE INTO SOUTHWESTERN NORTH DAKOTA
AROUND 23 UTC. WHILE THAT WILL LIKELY BE THE BEST CHANCE FOR
STRONGER THUNDERSTORMS...CURRENT RADAR CONFIRMS THAT SHOWERS AHEAD
OF THAT FEATURE WILL ALSO SPREAD ACROSS THE MISSOURI SLOPE THIS
AFTERNOON...THOUGH NO LIGHTENING HAS BEEN OBSERVED THERE. LOOK
FOR THIS TREND TO CONTINUE AND FILL IN THROUGH THE AFTERNOON AS
MORE FAVORABLE DYNAMIC FORCING MOVES INTO THE REGION.

THERE IS A SPC SLIGHT RISK FOR SEVERE THUNDERSTORMS ON SATURDAY
AFTERNOON ASSOCIATED WITH A DEEPENING SURFACE LOW. NORTH DAKOTA
LOOKS TO BE ON THE NORTH SIDE OF THE WARM FRONT. WHILE LOW-LEVEL
WINDS WILL BE BACKED...FORECAST CLOUD COVER JUSTIFIED MODEL
SOUNDINGS NOT FAVORABLE FOR SURFACE-BASED CONVECTION. THUS...THE
MAIN THREATS WILL BE LARGE HAIL AND DAMAGING WINDS UNLESS CLEARING
MOVES INTO SOUTH CENTRAL NORTH DAKOTA.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 258 PM CDT FRI MAY 17 2013

THE MAIN FORECAST HIGHLIGHT FOR THE EXTENDED PERIOD CONTINUES TO BE
THE MODERATE TO HEAVY RAIN EVENT THROUGH EARLY TUESDAY.

THE 12Z DETERMINISTIC MODEL SUITE IS IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD BEFORE SOLUTIONS DIVERGE IN REGARDS OF THE FORMATION
AND MOVEMENT OF THE UPPER LEVEL LOW ACROSS THE NORTHERN PLAINS
MONDAY THROUGH WEDNESDAY. A BROAD WESTERN CONUS UPPER LEVEL TROUGH
IS PROGGED TO PUSH EAST AND OVER THE PLAINS SATURDAY AND
SUNDAY...CLOSE OFF OVER THE NORTHERN AND CENTRAL PLAINS LATE SUNDAY
AND MONDAY...AND THEN SLOWLY PUSH EAST AND WEAKEN THROUGH THURSDAY.
THE 12Z GFS REMAINS THE PROGRESSIVE SOLUTION MOVING AND WEAKENING
THE CLOSED OFF LOW AWAY FROM THE DAKOTAS BY WEDNESDAY...WHILE THE
12Z ECMWF/GEM KEEPS IT MEANDERING OVER THE DAKOTAS BEFORE PUSHING
EAST AND WEAKENING BY LATE NEXT WEEK. MEANWHILE...A REX BLOCKING
PATTERN OVER NORTHERN AMERICA WILL BEGIN TO SET UP AS UPPER LEVEL
RIDGING TAKES PLACE NORTH OF THE AFOREMENTIONED CLOSED OFF LOW AND
ANOTHER TROUGH DROPS SOUTH FROM THE NORTHEASTERN PACIFIC.

AS A RESULT IN THE DIFFERENCES IN THE POSITIONING AND MOVEMENT OF THE
AFOREMENTIONED LOW...PLACEMENT AND AMOUNT OF PRECIPITATION DIFFER
BETWEEN THE GFS AND THE GEM/ECMWF SOLUTIONS...MOST NOTABLY ON MONDAY
AND TUESDAY. THE ECMWF/GEM CONTINUE CHANCES FOR PRECIPITATION ON
THESE DAYS AS THE LOW HOVERS OVERHEAD...WHILE THE GFS KEEPS MOST OF
THE NORTH AND WEST DRY...WITH PRECIPITATION CHANCES FOR THE
SOUTHEAST PART OF THE STATE. HAVE DECIDED TO STICK CLOSE TO WPC
GUIDANCE FOR QPF...WHICH KEEPS THE JAMES RIVER VALLEY ON TRACK FOR
ONE TO TWO INCHES OF RAINFALL FROM SATURDAY EVENING THROUGH
TUESDAY...WITH LESSER AMOUNTS FURTHER NORTHWEST. IN REGARDS TO ANY
POTENTIAL FLOODING ISSUES...CONDITIONS ARE SUCH THAT SOILS CAN
ABSORB SIGNIFICANT RAINFALL. THUS...SIGNIFICANT RISES ON MAIN STEM
RIVERS SUCH AS THE SOURIS AND JAMES ARE NOT EXPECTED.
HOWEVER...ENHANCED RAINFALL RATES OR SEVERAL ROUNDS OF STORMS COULD
PRODUCE LOCALIZED RUNOFF...LEADING TO RISES ON SMALL CREEKS AND
STREAMS...AND POSSIBLY FLASH FLOODING.

PRECIPITATION CHANCES WILL BEGIN TO DIMINISH LATE TUESDAY AND INTO
WEDNESDAY AS DRY AND SEASONABLE CONDITIONS TAKE OVER....WITH AN
ADDITIONAL CHANCE FOR SHOWERS POSSIBLY THURSDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1252 AM CDT SAT MAY 18 2013

SHOWERS AND THUNDERSTORMS WILL CONTINUE TO SPREAD NORTH AND IMPACT
ALL TAF SITES OVERNIGHT. COVERAGE OF STORMS IS EXPECTED TO BE
RATHER LIMITED DURING THE MORNING HOURS SATURDAY...THEN INCREASE
AGAIN SATURDAY AFTERNOON AND EVENING WITH MAINLY MVFR CEILINGS
AND/OR VISIBILITIES DEVELOPING.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...RK
SHORT TERM...SCHECK
LONG TERM...LTH
AVIATION...RK

000
FXUS63 KFGF 180441
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
1141 PM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 1141 PM CDT FRI MAY 17 2013

LOWERED TEMPS A BIT IN THE NORTHWESTERN CWA WHERE READINGS HAVE
ALREADY FALLEN INTO THE MID 50S. THINK THAT TEMPS WILL LEVEL OFF
AROUND 50 AS CLOUDS CONTINUE TO INCREASE BUT TEMPS ALREADY AT
FORECAST LOWS. RADAR SHOWS THAT STORMS CONTINUE TO BE ON TRACK TO
ENTER THE SOUTHWESTERN CWA AFTER MIDNIGHT AND CONTINUE
NORTHEASTWARD. SEE LITTLE REASON TO MAKE MORE ADJUSTMENTS TO THE
TIMING OF POPS AT THIS POINT.

UPDATE ISSUED AT 927 PM CDT FRI MAY 17 2013

ADJUSTED POPS/WX BASED ON CURRENT RADAR TIMING. STORMS FIRING
ALONG THE 850MB WARM AIR ADVECTION IN CENTRAL MN WILL CLIP OUR
SOUTHEASTERN COUNTIES...SO INCLUDED A SCATTERED MENTION FOR THE
REST OF THE EVENING. STORMS FIRING OVER WESTERN ND AND SD WILL
MOVE NORTHEASTWARD INTO THE SOUTHERN RED RIVER VALLEY LATER
TONIGHT. IF CURRENT MOTION HOLDS...THE ACTIVITY SHOULD ARRIVE AT
OUR SOUTHERN BORDER AROUND MIDNIGHT AND MOVE NORTHEASTWARD
THROUGHOUT THE EARLY MORNING HOURS. TWEAKED TIMING OF POPS MOVING
INTO THE AREA WITH LIKELY WORDING TRANSITIONING FROM THE SOUTH
JUST AFTER MIDNIGHT TO THE NORTH BY TOMORROW MORNING. ELEVATED CAP
VALUES ARE AROUND 1000 J/KG ACCORDING TO THE SPC MESOANALYSIS.
THINK THAT THE BEST LLJ WILL STAY TO OUR SOUTH BUT SOME ISOLATED
SEVERE HAIL OR WIND IS NOT OUT OF THE QUESTION AROUND THE 06-12Z
TIME FRAME. HOWEVER...CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE IN
THE GRIDS AT THIS POINT SO WILL JUST KEEP GENERAL THUNDER GOING.

UPDATE ISSUED AT 652 PM CDT FRI MAY 17 2013

ADJUSTED POPS ALONG THE CANADIAN BORDER FOR THE NEXT FEW HOURS TO
ACCOUNT FOR THE WEAK SHOWERS/SPRINKLES DEVELOPING IN THAT AREA.
HOWEVER...THE MAIN PRECIP IS WELL TO OUR SOUTH...SO KEPT THE HIGH
POPS RESERVED FOR AFTER MIDNIGHT AS THE GOING FORECAST HAS.
TWEAKED CLOUDS TO INCLUDE CLEARING IN OUR SOUTHWESTERN COUNTIES
BUT THAT WILL NOT LAST LONG AS BLOW OFF FROM CONVECTION FROM OUR
SOUTHWEST BEGINS TO MOVE IN. SHOULD BE TOTALLY CLOUDY AFTER
MIDNIGHT.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 330 PM CDT FRI MAY 17 2013

THE MAIN CONCERNS WILL BE HEAVY RAIN AND SEVERE POTENTIAL. 12Z
MODELS IN DECENT AGREEMENT WITH SYNOPTIC FEATURES...BUT STILL
ENOUGH DIFFERENCES THAT CONFIDENCE IS LOW WITH DETAILS.

WEST COAST TROUGH WILL GRADUALLY PROPAGATE EAST WITH MULTIPLE
SHORTWAVES EJECTING INTO THE REGION. HARD TO PINPOINT EXACTLY WHEN
AND WHERE THE BEST THUNDER CHANCES WILL BE...BUT THE MODELS DO
OFFER A COUPLE STRONGER SIGNALS. THE FIRST BEST CHANCE IS TONIGHT
INTO SATURDAY MORNING AS MENTIONED IN THE PREVIOUS AFD (1243PM).
18Z HRRR DOES INDICATE A THUNDERSTORM COMPLEX MOVING INTO THE
SOUTHERN FA AFTER 06Z...ALONG WITH WITH ISOLATED STRONGER STORMS.
THIS COMPLEX SHOULD MOVE THROUGH FAIRLY QUICKLY...WITH UP TO 0.5
INCH AREAL QPF POSSIBLE.

THINKING THERE WILL BE A BRIEF BREAK IN ACTIVITY ON SATURDAY.
SEVERE POTENTIAL WILL DEPEND ON HOW FAR NORTH THE SURFACE WARM
FRONT WILL MAKE IT BY SATURDAY AFTERNOON. THE GEM/GFS BRING THIS
FEATURE MUCH FURTHER NORTH THAN OTHER MODELS (LIKELY BECAUSE THEY
ARE STRONGER WITH A SHORTWAVE INTO SOUTHERN CANADA). AT ANY
RATE...GIVEN THIS TIME OF YEAR WITHOUT EVAPOTRANSPIRATION...THE
NAM SEEMS TO HAVE THE CORRECT IDEA INDICATING MLCAPE 1000-1500
J/KG WITHIN THE WARM SECTOR. THIS INSTABILITY ALONG WITH DEEP
LAYER SHEAR 30-35 KNOTS SHOULD BE ENOUGH FOR LIMITED SEVERE
POTENTIAL WITHIN THE WARM SECTOR AS THE COLD FRONT SLOWLY
PROPAGATES EAST INTO THE EVENING HOURS.

THE BEST CHANCE FOR FLASH FLOODING POTENTIAL WOULD BE SATURDAY
EVENING AND OVERNIGHT ALONG THE SLOW MOVING BOUNDARY. THE BIGGEST
QUESTIONS AT THIS POINT WILL BE THE EXACT LOCATION OF THIS
FEATURE...AND HOW QUICKLY IT WILL MOVE TO THE EAST. NOT ENOUGH
CONFIDENCE FOR A FLASH FLOOD WATCH AT THIS POINT...BUT THERE IS A
SLIGHT RISK FOR FLASH FLOODING ALONG AND EAST OF THE VALLEY.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 PM CDT FRI MAY 17 2013

SUNDAY-MONDAY...UPPER LOW WILL CLOSE OFF JUST SOUTH OF THE FA AND
BRING PERIODIC SHOWERS AND THUNDERSTORMS TO THE REGION.
INSTABILITY IS MUCH WEAKER BY THIS TIME...BUT GIVEN HIGH PWATS AN
ADDITIONAL 1-2 INCHES OF RAINFALL IS POSSIBLE (ESPECIALLY THE
SOUTHERN HALF OF THE FA). THIS RAINFALL WOULD OVER A COUPLE DAYS
AND ANY FLOOD THREAT IS DEPENDENT ON WHAT OCCURS SATURDAY/SATURDAY
NIGHT.

MONDAY NIGHT-FRIDAY...12Z GFS/12Z ECMWF IN PRETTY GOOD AGREEMENT
IN SHOWING THE 500 MB LOW OVER EASTERN SD/MN REGION TUESDAY THEN
DRIFTING A BIT SOUTH AND EAST WEDNESDAY AND THEN EAST OF THE AREA
THURSDAY. LOOK FOR A CONTINUED HIGH THREAT FOR SHOWERS
TUESDAY...DIMINISHING ON WEDNESDAY. A 500 MB RIDGE WILL BUILD IN
BEHIND THE LOW FOR THE END OF THE WEEK WITH DRY WEATHER RETURNING.
LOOK FOR TEMPS TO BIT A BIT BELOW NORMAL WITH THE CLOUDS/RAIN TUE-
WED THEN RETURN TO CLOSE TO NORMAL LEVELS BY LATE WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1141 PM CDT FRI MAY 17 2013

CEILINGS HAVE GONE DOWN TO MVFR AT KFAR AND THE LOWER CONDITIONS
WILL CONTINUE TO SPREAD NORTHWARD THROUGH MUCH OF THE NIGHT.
WEAKENING STORMS WILL ENTER THE FORECAST AREA AFTER
MIDNIGHT...MOVING INTO KFAR AREA AROUND 07-08Z WITH SOME THUNDER
REMAINING AND CONTINUING NORTH AS MOSTLY SHOWERS LATER ON THIS
MORNING. THINK THERE SHOULD BE SOME IMPROVEMENT TO VFR CONDITIONS
ACROSS MOST AREAS DURING THE AFTERNOON ALTHOUGH WILL HAVE TO WATCH
THE NORTHERN SITES WHICH MAY BE ON THE NORTH SIDE OF A WARM FRONT
AND STAY SOCKED IN. KFAR HAS THE BEST CHANCE OF SEEING SOME
CONVECTIVE REDEVELOPENT TOWARDS THE END OF THE PERIOD.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/RIDDLE
AVIATION...JR

000
FXUS63 KBIS 180310
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
1010 PM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 1010 PM CDT FRI MAY 17 2013

A PERSISTENT SEVERE THUNDERSTORM CONTINUES TO MOVE EAST-NORTHEAST
ACROSS SOUTHWESTERN AND SOUTH CENTRAL NORTH DAKOTA. IT IS CURRENTLY
MOVING INTO WESTERN GRANT COUNTY AT THE TIME OF THIS WRITING. THIS
STORM HAS A HISTORY OF PRODUCING 60 MPH WINDS AND HEAVY RAIN.
HOWEVER...LITTLE TO NO HAIL HAS BEEN REPORTED.

UNCERTAINTY REMAINS HIGH FOR THE FORECAST FOR THE REMAINDER OF
THE NIGHT. FOR THE SAKE OF CONSISTENCY...CONTINUED TO FORECAST ALONG
THE LINES OF THE PREVIOUS UPDATE DISCUSSED BELOW. ONLY MODIFIED
HOURLY SENSIBLE WEATHER GRIDS BASED ON CURRENT OBS/TRENDS. THE
UPDATED PRODUCTS HAVE BEEN SENT.

UPDATE ISSUED AT 717 PM CDT FRI MAY 17 2013

SHORT RANGE MODEL GUIDANCE CONTINUES TO STRUGGLE RESOLVING
CONVECTIVE ACTIVITY ACROSS PORTIONS OF THE NORTHERN PLAINS THIS
EVENING. THE ONLY EVENING CONVECTION AFFECTING WESTERN AND CENTRAL
NORTH DAKOTA IS JUST NOW NOSING ITS WAY INTO EXTREME SOUTHWESTERN
NORTH DAKOTA. THIS ACTIVITY SHOULD CONTINUE TO MOVE EAST-NORTHEAST
THROUGH THE EVENING HOURS ALONG THE 850MB-300MB MEAN WIND. AS A
RESULT...LOWERED EVENING POPS FOR ALL BUT SOUTHWESTERN AND SOUTH
CENTRAL NORTH DAKOTA.

AFTER MIDNIGHT...THE ECMWF AND NAM PROG A TIGHT THETA-E GRADIENT
DEVELOPING OVER CENTRAL NORTH DAKOTA (MAINLY ALONG AND NORTH OF
I-94). SUBSEQUENTLY...THESE MODELS PROG THIS HIGHEST QPF TO
DEVELOP THERE. ON THE OTHER HAND...THE GEM AND GFS ARE KEYING IN
ON AN UPSTREAM SHORTWAVE AND PROG THE HIGHEST QPF TO DEVELOP OVER
NORTHWESTERN NORTH DAKOTA. GIVEN THE MODEL TO MODEL
INCONSISTENCIES...MAINTAINED LIKELY POPS DEVELOPING AREAWIDE AFTER
MIDNIGHT. KEPT THE HIGHEST QPF NEAR THE I-94 CORRIDOR.
HOWEVER...CONFIDENCE IS LOW REGARDING THE PLACEMENT OF THE HIGHEST
QPF. WILL CONTINUE TO MONITOR EVENING TRENDS AND MODIFY AS NEEDED.

THE UPDATED GRIDDED AND TEXT PRODUCTS HAVE BEEN SENT.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 258 PM CDT FRI MAY 17 2013

THE MAIN SHORT TERM FOCUS IS PRECIPITATION THROUGH SATURDAY.

PRECIPITATION CHANCES HAVE GENERALLY BEEN LOWERED FROM CONTINUITY
BASED ON MODEL CONSENSUS AND COORDINATION WITH SURROUNDING
OFFICES. THEY NOW REFLECT THE BEST CHANCES FOR SHOWERS AND
THUNDERSTORMS. UNFORTUNATELY...THE AVAILABLE 12 UTC THROUGH 18 UTC
GUIDANCE DISAGREES WITH TIMING AND COVERAGE ACROSS MUCH OF THE
STATE FOR THIS AFTERNOON AND TONIGHT...BUT THERE IS GENERAL
AGREEMENT THAT AN AREA OF CONVECTION WILL DEVELOP OVER
SOUTHEASTERN MONTANA THIS AFTERNOON AND MOVE EAST-NORTHEAST.

WATER VAPOR SATELLITE IMAGERY INDICATES THE LEADING EDGE OF THE
NEXT MID LEVEL SHORTWAVE WILL NOSE INTO SOUTHWESTERN NORTH DAKOTA
AROUND 23 UTC. WHILE THAT WILL LIKELY BE THE BEST CHANCE FOR
STRONGER THUNDERSTORMS...CURRENT RADAR CONFIRMS THAT SHOWERS AHEAD
OF THAT FEATURE WILL ALSO SPREAD ACROSS THE MISSOURI SLOPE THIS
AFTERNOON...THOUGH NO LIGHTENING HAS BEEN OBSERVED THERE. LOOK
FOR THIS TREND TO CONTINUE AND FILL IN THROUGH THE AFTERNOON AS
MORE FAVORABLE DYNAMIC FORCING MOVES INTO THE REGION.

THERE IS A SPC SLIGHT RISK FOR SEVERE THUNDERSTORMS ON SATURDAY
AFTERNOON ASSOCIATED WITH A DEEPENING SURFACE LOW. NORTH DAKOTA
LOOKS TO BE ON THE NORTH SIDE OF THE WARM FRONT. WHILE LOW-LEVEL
WINDS WILL BE BACKED...FORECAST CLOUD COVER JUSTIFIED MODEL
SOUNDINGS NOT FAVORABLE FOR SURFACE-BASED CONVECTION. THUS...THE
MAIN THREATS WILL BE LARGE HAIL AND DAMAGING WINDS UNLESS CLEARING
MOVES INTO SOUTH CENTRAL NORTH DAKOTA.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 258 PM CDT FRI MAY 17 2013

THE MAIN FORECAST HIGHLIGHT FOR THE EXTENDED PERIOD CONTINUES TO BE
THE MODERATE TO HEAVY RAIN EVENT THROUGH EARLY TUESDAY.

THE 12Z DETERMINISTIC MODEL SUITE IS IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD BEFORE SOLUTIONS DIVERGE IN REGARDS OF THE FORMATION
AND MOVEMENT OF THE UPPER LEVEL LOW ACROSS THE NORTHERN PLAINS
MONDAY THROUGH WEDNESDAY. A BROAD WESTERN CONUS UPPER LEVEL TROUGH
IS PROGGED TO PUSH EAST AND OVER THE PLAINS SATURDAY AND
SUNDAY...CLOSE OFF OVER THE NORTHERN AND CENTRAL PLAINS LATE SUNDAY
AND MONDAY...AND THEN SLOWLY PUSH EAST AND WEAKEN THROUGH THURSDAY.
THE 12Z GFS REMAINS THE PROGRESSIVE SOLUTION MOVING AND WEAKENING
THE CLOSED OFF LOW AWAY FROM THE DAKOTAS BY WEDNESDAY...WHILE THE
12Z ECWMF/GEM KEEPS IT MEANDERING OVER THE DAKOTAS BEFORE PUSHING
EAST AND WEAKENING BY LATE NEXT WEEK. MEANWHILE...A REX BLOCKING
PATTERN OVER NORTHERN AMERICA WILL BEGIN TO SET UP AS UPPER LEVEL
RIDGING TAKES PLACE NORTH OF THE AFOREMENTIONED CLOSED OFF LOW AND
ANOTHER TROUGH DROPS SOUTH FROM THE NORTHEASTERN PACIFIC.

AS A RESULT IN THE DIFFERENCES IN THE POSITIONING AND MOVEMENT OF THE
AFOREMENTIONED LOW...PLACEMENT AND AMOUNT OF PRECIPITATION DIFFER
BETWEEN THE GFS AND THE GEM/ECWMF SOLUTIONS...MOST NOTABLY ON MONDAY
AND TUESDAY. THE ECWMF/GEM CONTINUE CHANCES FOR PRECIPITATION ON
THESE DAYS AS THE LOW HOVERS OVERHEAD...WHILE THE GFS KEEPS MOST OF
THE NORTH AND WEST DRY...WITH PRECIPITATION CHANCES FOR THE
SOUTHEAST PART OF THE STATE. HAVE DECIDED TO STICK CLOSE TO WPC
GUIDANCE FOR QPF...WHICH KEEPS THE JAMES RIVER VALLEY ON TRACK FOR
ONE TO TWO INCHES OF RAINFALL FROM SATURDAY EVENING THROUGH
TUESDAY...WITH LESSER AMOUNTS FURTHER NORTHWEST. IN REGARDS TO ANY
POTENTIAL FLOODING ISSUES...CONDITIONS ARE SUCH THAT SOILS CAN
ABSORB SIGNIFICANT RAINFALL. THUS...SIGNIFICANT RISES ON MAIN STEM
RIVERS SUCH AS THE SOURIS AND JAMES ARE NOT EXPECTED.
HOWEVER...ENHANCED RAINFALL RATES OR SEVERAL ROUNDS OF STORMS COULD
PRODUCE LOCALIZED RUNOFF...LEADING TO RISES ON SMALL CREEKS AND
STREAMS...AND POSSIBLY FLASH FLOODING.

PRECIPITATION CHANCES WILL BEGIN TO DIMINISH LATE TUESDAY AND INTO
WEDNESDAY AS DRY AND SEASONABLE CONDITIONS TAKE OVER....WITH AN
ADDITIONAL CHANCE FOR SHOWERS POSSIBLY THURSDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 24Z SATURDAY EVENING)
ISSUED AT 717 PM CDT FRI MAY 17 2013

VFR CONDITIONS AT ALL TAF SITES WILL EVENTUALLY BECOME MVFR
TONIGHT AS WIDESPREAD SHOWERS AND THUNDERSTORMS ACCOMPANY LOWER
CEILINGS. THE OFFENDING LARGE LOW PRESSURE SYSTEM WILL REMAIN OVER
THE NORTHERN PLAINS THROUGH AT LEAST MONDAY. THUNDERSTORMS WILL BE
MORE WIDESPREAD SATURDAY AFTERNOON AND EVENING.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

UPDATE...TM
SHORT TERM...SCHECK
LONG TERM...LTH
AVIATION...TM

000
FXUS63 KFGF 180228
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
928 PM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 927 PM CDT FRI MAY 17 2013

ADJUSTED POPS/WX BASED ON CURRENT RADAR TIMING. STORMS FIRING
ALONG THE 850MB WARM AIR ADVECTION IN CENTRAL MN WILL CLIP OUR
SOUTHEASTERN COUNTIES...SO INCLUDED A SCATTERED MENTION FOR THE
REST OF THE EVENING. STORMS FIRING OVER WESTERN ND AND SD WILL
MOVE NORTHEASTWARD INTO THE SOUTHERN RED RIVER VALLEY LATER
TONIGHT. IF CURRENT MOTION HOLDS...THE ACTIVITY SHOULD ARRIVE AT
OUR SOUTHERN BORDER AROUND MIDNIGHT AND MOVE NORTHEASTWARD
THROUGHOUT THE EARLY MORNING HOURS. TWEAKED TIMING OF POPS MOVING
INTO THE AREA WITH LIKELY WORDING TRANSITIONING FROM THE SOUTH
JUST AFTER MIDNIGHT TO THE NORTH BY TOMORROW MORNING. ELEVATED CAP
VALUES ARE AROUND 1000 J/KG ACCORDING TO THE SPC MESOANALYSIS.
THINK THAT THE BEST LLJ WILL STAY TO OUR SOUTH BUT SOME ISOLATED
SEVERE HAIL OR WIND IS NOT OUT OF THE QUESTION AROUND THE 06-12Z
TIME FRAME. HOWEVER...CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE IN
THE GRIDS AT THIS POINT SO WILL JUST KEEP GENERAL THUNDER GOING.

UPDATE ISSUED AT 652 PM CDT FRI MAY 17 2013

ADJUSTED POPS ALONG THE CANADIAN BORDER FOR THE NEXT FEW HOURS TO
ACCOUNT FOR THE WEAK SHOWERS/SPRINKLES DEVELOPING IN THAT AREA.
HOWEVER...THE MAIN PRECIP IS WELL TO OUR SOUTH...SO KEPT THE HIGH
POPS RESERVED FOR AFTER MIDNIGHT AS THE GOING FORECAST HAS.
TWEAKED CLOUDS TO INCLUDE CLEARING IN OUR SOUTHWESTERN COUNTIES
BUT THAT WILL NOT LAST LONG AS BLOW OFF FROM CONVECTION FROM OUR
SOUTHWEST BEGINS TO MOVE IN. SHOULD BE TOTALLY CLOUDY AFTER
MIDNIGHT.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 330 PM CDT FRI MAY 17 2013

THE MAIN CONCERNS WILL BE HEAVY RAIN AND SEVERE POTENTIAL. 12Z
MODELS IN DECENT AGREEMENT WITH SYNOPTIC FEATURES...BUT STILL
ENOUGH DIFFERENCES THAT CONFIDENCE IS LOW WITH DETAILS.

WEST COAST TROUGH WILL GRADUALLY PROPAGATE EAST WITH MULTIPLE
SHORTWAVES EJECTING INTO THE REGION. HARD TO PINPOINT EXACTLY WHEN
AND WHERE THE BEST THUNDER CHANCES WILL BE...BUT THE MODELS DO
OFFER A COUPLE STRONGER SIGNALS. THE FIRST BEST CHANCE IS TONIGHT
INTO SATURDAY MORNING AS MENTIONED IN THE PREVIOUS AFD (1243PM).
18Z HRRR DOES INDICATE A THUNDERSTORM COMPLEX MOVING INTO THE
SOUTHERN FA AFTER 06Z...ALONG WITH WITH ISOLATED STRONGER STORMS.
THIS COMPLEX SHOULD MOVE THROUGH FAIRLY QUICKLY...WITH UP TO 0.5
INCH AREAL QPF POSSIBLE.

THINKING THERE WILL BE A BRIEF BREAK IN ACTIVITY ON SATURDAY.
SEVERE POTENTIAL WILL DEPEND ON HOW FAR NORTH THE SURFACE WARM
FRONT WILL MAKE IT BY SATURDAY AFTERNOON. THE GEM/GFS BRING THIS
FEATURE MUCH FURTHER NORTH THAN OTHER MODELS (LIKELY BECAUSE THEY
ARE STRONGER WITH A SHORTWAVE INTO SOUTHERN CANADA). AT ANY
RATE...GIVEN THIS TIME OF YEAR WITHOUT EVAPOTRANSPIRATION...THE
NAM SEEMS TO HAVE THE CORRECT IDEA INDICATING MLCAPE 1000-1500
J/KG WITHIN THE WARM SECTOR. THIS INSTABILITY ALONG WITH DEEP
LAYER SHEAR 30-35 KNOTS SHOULD BE ENOUGH FOR LIMITED SEVERE
POTENTIAL WITHIN THE WARM SECTOR AS THE COLD FRONT SLOWLY
PROPAGATES EAST INTO THE EVENING HOURS.

THE BEST CHANCE FOR FLASH FLOODING POTENTIAL WOULD BE SATURDAY
EVENING AND OVERNIGHT ALONG THE SLOW MOVING BOUNDARY. THE BIGGEST
QUESTIONS AT THIS POINT WILL BE THE EXACT LOCATION OF THIS
FEATURE...AND HOW QUICKLY IT WILL MOVE TO THE EAST. NOT ENOUGH
CONFIDENCE FOR A FLASH FLOOD WATCH AT THIS POINT...BUT THERE IS A
SLIGHT RISK FOR FLASH FLOODING ALONG AND EAST OF THE VALLEY.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 PM CDT FRI MAY 17 2013

SUNDAY-MONDAY...UPPER LOW WILL CLOSE OFF JUST SOUTH OF THE FA AND
BRING PERIODIC SHOWERS AND THUNDERSTORMS TO THE REGION.
INSTABILITY IS MUCH WEAKER BY THIS TIME...BUT GIVEN HIGH PWATS AN
ADDITIONAL 1-2 INCHES OF RAINFALL IS POSSIBLE (ESPECIALLY THE
SOUTHERN HALF OF THE FA). THIS RAINFALL WOULD OVER A COUPLE DAYS
AND ANY FLOOD THREAT IS DEPENDENT ON WHAT OCCURS SATURDAY/SATURDAY
NIGHT.

MONDAY NIGHT-FRIDAY...12Z GFS/12Z ECMWF IN PRETTY GOOD AGREEMENT
IN SHOWING THE 500 MB LOW OVER EASTERN SD/MN REGION TUESDAY THEN
DRIFTING A BIT SOUTH AND EAST WEDNESDAY AND THEN EAST OF THE AREA
THURSDAY. LOOK FOR A CONTINUED HIGH THREAT FOR SHOWERS
TUESDAY...DIMINISHING ON WEDNESDAY. A 500 MB RIDGE WILL BUILD IN
BEHIND THE LOW FOR THE END OF THE WEEK WITH DRY WEATHER RETURNING.
LOOK FOR TEMPS TO BIT A BIT BELOW NORMAL WITH THE CLOUDS/RAIN TUE-
WED THEN RETURN TO CLOSE TO NORMAL LEVELS BY LATE WEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 652 PM CDT FRI MAY 17 2013

VFR CLOUDS WILL CONTINUE OVER MUCH OF THE AREA...BUT SOME MVFR
CEILINGS OVER THE SOUTHEASTERN FORECAST AREA WILL BEGIN TO SPREAD
NORTH AND WEST LATER ON TONIGHT. HAVE KFAR DECREASING TO MVFR
AFTER MIDNIGHT AND THE OTHER SITES MORE TOWARDS MORNING. SHOWERS
AND A FEW THUNDERSTORMS WILL MOVE IN AFTER MIDNIGHT...WITH THE
BEST CONVECTION IN THE SOUTH AROUND KFAR WHILE THE NORTHERN SITES
WILL BE MORE SHOWERY. WINDS WILL SHIFT TO A MORE SOUTHERLY
DIRECTION DURING THE DAY TOMORROW AS A WARM FRONT LIFTS NORTH INTO
THE AREA...ALTHOUGH THERE IS STILL SOME UNCERTAINTY AS TO EXACTLY
WHERE THE BOUNDARY WILL END UP. FOR NOW HAVE IT GOING PAST OUR
NORTHERN TAF SITES BY LATE IN THE PERIOD BUT THE BOUNDARY MAY
STALL OUT AND LEAVE THEM IN EASTERLY WINDS AND MORE RAIN. THINK
THAT THERE SHOULD BE SOME BRIEF IMPROVEMENT TO VFR IN MOST SITES
DURING THE LATE MORNING OR AFTERNOON ALTHOUGH MUCH WILL DEPEND ON
HOW EARLY MORNING CONVECTION PLAYS OUT.


&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/RIDDLE
AVIATION...JR

000
FXUS63 KBIS 180016
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
716 PM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 717 PM CDT FRI MAY 17 2013

SHORT RANGE MODEL GUIDANCE CONTINUES TO STRUGGLE RESOLVING
CONVECTIVE ACTIVITY ACROSS PORTIONS OF THE NORTHERN PLAINS THIS
EVENING. THE ONLY EVENING CONVECTION AFFECTING WESTERN AND CENTRAL
NORTH DAKOTA IS JUST NOW NOSING ITS WAY INTO EXTREME SOUTHWESTERN
NORTH DAKOTA. THIS ACTIVITY SHOULD CONTINUE TO MOVE EAST-NORTHEAST
THROUGH THE EVENING HOURS ALONG THE 850MB-300MB MEAN WIND. AS A
RESULT...LOWERED EVENING POPS FOR ALL BUT SOUTHWESTERN AND SOUTH
CENTRAL NORTH DAKOTA.

AFTER MIDNIGHT...THE ECMWF AND NAM PROG A TIGHT THETA-E GRADIENT
DEVELOPING OVER CENTRAL NORTH DAKOTA (MAINLY ALONG AND NORTH OF
I-94). SUBSEQUENTLY...THESE MODELS PROG THIS HIGHEST QPF TO
DEVELOP THERE. ON THE OTHER HAND...THE GEM AND GFS ARE KEYING IN
ON AN UPSTREAM SHORTWAVE AND PROG THE HIGHEST QPF TO DEVELOP OVER
NORTHWESTERN NORTH DAKOTA. GIVEN THE MODEL TO MODEL
INCONSISTENCIES...MAINTAINED LIKELY POPS DEVELOPING AREAWIDE AFTER
MIDNIGHT. KEPT THE HIGHEST QPF NEAR THE I-94 CORRIDOR.
HOWEVER...CONFIDENCE IS LOW REGARDING THE PLACEMENT OF THE HIGHEST
QPF. WILL CONTINUE TO MONITOR EVENING TRENDS AND MODIFY AS NEEDED.

THE UPDATED GRIDDED AND TEXT PRODUCTS HAVE BEEN SENT.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 258 PM CDT FRI MAY 17 2013

THE MAIN SHORT TERM FOCUS IS PRECIPITATION THROUGH SATURDAY.

PRECIPITATION CHANCES HAVE GENERALLY BEEN LOWERED FROM CONTINUITY
BASED ON MODEL CONSENSUS AND COORDINATION WITH SURROUNDING
OFFICES. THEY NOW REFLECT THE BEST CHANCES FOR SHOWERS AND
THUNDERSTORMS. UNFORTUNATELY...THE AVAILABLE 12 UTC THROUGH 18 UTC
GUIDANCE DISAGREES WITH TIMING AND COVERAGE ACROSS MUCH OF THE
STATE FOR THIS AFTERNOON AND TONIGHT...BUT THERE IS GENERAL
AGREEMENT THAT AN AREA OF CONVECTION WILL DEVELOP OVER
SOUTHEASTERN MONTANA THIS AFTERNOON AND MOVE EAST-NORTHEAST.

WATER VAPOR SATELLITE IMAGERY INDICATES THE LEADING EDGE OF THE
NEXT MID LEVEL SHORTWAVE WILL NOSE INTO SOUTHWESTERN NORTH DAKOTA
AROUND 23 UTC. WHILE THAT WILL LIKELY BE THE BEST CHANCE FOR
STRONGER THUNDERSTORMS...CURRENT RADAR CONFIRMS THAT SHOWERS AHEAD
OF THAT FEATURE WILL ALSO SPREAD ACROSS THE MISSOURI SLOPE THIS
AFTERNOON...THOUGH NO LIGHTENING HAS BEEN OBSERVED THERE. LOOK
FOR THIS TREND TO CONTINUE AND FILL IN THROUGH THE AFTERNOON AS
MORE FAVORABLE DYNAMIC FORCING MOVES INTO THE REGION.

THERE IS A SPC SLIGHT RISK FOR SEVERE THUNDERSTORMS ON SATURDAY
AFTERNOON ASSOCIATED WITH A DEEPENING SURFACE LOW. NORTH DAKOTA
LOOKS TO BE ON THE NORTH SIDE OF THE WARM FRONT. WHILE LOW-LEVEL
WINDS WILL BE BACKED...FORECAST CLOUD COVER JUSTIFIED MODEL
SOUNDINGS NOT FAVORABLE FOR SURFACE-BASED CONVECTION. THUS...THE
MAIN THREATS WILL BE LARGE HAIL AND DAMAGING WINDS UNLESS CLEARING
MOVES INTO SOUTH CENTRAL NORTH DAKOTA.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 258 PM CDT FRI MAY 17 2013

THE MAIN FORECAST HIGHLIGHT FOR THE EXTENDED PERIOD CONTINUES TO BE
THE MODERATE TO HEAVY RAIN EVENT THROUGH EARLY TUESDAY.

THE 12Z DETERMINISTIC MODEL SUITE IS IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD BEFORE SOLUTIONS DIVERGE IN REGARDS OF THE FORMATION
AND MOVEMENT OF THE UPPER LEVEL LOW ACROSS THE NORTHERN PLAINS
MONDAY THROUGH WEDNESDAY. A BROAD WESTERN CONUS UPPER LEVEL TROUGH
IS PROGGED TO PUSH EAST AND OVER THE PLAINS SATURDAY AND
SUNDAY...CLOSE OFF OVER THE NORTHERN AND CENTRAL PLAINS LATE SUNDAY
AND MONDAY...AND THEN SLOWLY PUSH EAST AND WEAKEN THROUGH THURSDAY.
THE 12Z GFS REMAINS THE PROGRESSIVE SOLUTION MOVING AND WEAKENING
THE CLOSED OFF LOW AWAY FROM THE DAKOTAS BY WEDNESDAY...WHILE THE
12Z ECWMF/GEM KEEPS IT MEANDERING OVER THE DAKOTAS BEFORE PUSHING
EAST AND WEAKENING BY LATE NEXT WEEK. MEANWHILE...A REX BLOCKING
PATTERN OVER NORTHERN AMERICA WILL BEGIN TO SET UP AS UPPER LEVEL
RIDGING TAKES PLACE NORTH OF THE AFOREMENTIONED CLOSED OFF LOW AND
ANOTHER TROUGH DROPS SOUTH FROM THE NORTHEASTERN PACIFIC.

AS A RESULT IN THE DIFFERENCES IN THE POSITIONING AND MOVEMENT OF THE
AFOREMENTIONED LOW...PLACEMENT AND AMOUNT OF PRECIPITATION DIFFER
BETWEEN THE GFS AND THE GEM/ECWMF SOLUTIONS...MOST NOTABLY ON MONDAY
AND TUESDAY. THE ECWMF/GEM CONTINUE CHANCES FOR PRECIPITATION ON
THESE DAYS AS THE LOW HOVERS OVERHEAD...WHILE THE GFS KEEPS MOST OF
THE NORTH AND WEST DRY...WITH PRECIPITATION CHANCES FOR THE
SOUTHEAST PART OF THE STATE. HAVE DECIDED TO STICK CLOSE TO WPC
GUIDANCE FOR QPF...WHICH KEEPS THE JAMES RIVER VALLEY ON TRACK FOR
ONE TO TWO INCHES OF RAINFALL FROM SATURDAY EVENING THROUGH
TUESDAY...WITH LESSER AMOUNTS FURTHER NORTHWEST. IN REGARDS TO ANY
POTENTIAL FLOODING ISSUES...CONDITIONS ARE SUCH THAT SOILS CAN
ABSORB SIGNIFICANT RAINFALL. THUS...SIGNIFICANT RISES ON MAIN STEM
RIVERS SUCH AS THE SOURIS AND JAMES ARE NOT EXPECTED.
HOWEVER...ENHANCED RAINFALL RATES OR SEVERAL ROUNDS OF STORMS COULD
PRODUCE LOCALIZED RUNOFF...LEADING TO RISES ON SMALL CREEKS AND
STREAMS...AND POSSIBLY FLASH FLOODING.

PRECIPITATION CHANCES WILL BEGIN TO DIMINISH LATE TUESDAY AND INTO
WEDNESDAY AS DRY AND SEASONABLE CONDITIONS TAKE OVER....WITH AN
ADDITIONAL CHANCE FOR SHOWERS POSSIBLY THURSDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 24Z SATURDAY EVENING)
ISSUED AT 717 PM CDT FRI MAY 17 2013

VFR CONDITIONS AT ALL TAF SITES WILL EVENTUALLY BECOME MVFR
TONIGHT AS WIDESPREAD SHOWERS AND THUNDERSTORMS ACCOMPANY LOWER
CEILINGS. THE OFFENDING LARGE LOW PRESSURE SYSTEM WILL REMAIN OVER
THE NORTHERN PLAINS THROUGH AT LEAST MONDAY. THUNDERSTORMS WILL BE
MORE WIDESPREAD SATURDAY AFTERNOON AND EVENING.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

UPDATE...TM
SHORT TERM...SCHECK
LONG TERM...LTH
AVIATION...TM

000
FXUS63 KFGF 172352
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
652 PM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 652 PM CDT FRI MAY 17 2013

ADJUSTED POPS ALONG THE CANADIAN BORDER FOR THE NEXT FEW HOURS TO
ACCOUNT FOR THE WEAK SHOWERS/SPRINKLES DEVELOPING IN THAT AREA.
HOWEVER...THE MAIN PRECIP IS WELL TO OUR SOUTH...SO KEPT THE HIGH
POPS RESERVED FOR AFTER MIDNIGHT AS THE GOING FORECAST HAS.
TWEAKED CLOUDS TO INCLUDE CLEARING IN OUR SOUTHWESTERN COUNTIES
BUT THAT WILL NOT LAST LONG AS BLOW OFF FROM CONVECTION FROM OUR
SOUTHWEST BEGINS TO MOVE IN. SHOULD BE TOTALLY CLOUDY AFTER
MIDNIGHT.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 330 PM CDT FRI MAY 17 2013

THE MAIN CONCERNS WILL BE HEAVY RAIN AND SEVERE POTENTIAL. 12Z
MODELS IN DECENT AGREEMENT WITH SYNOPTIC FEATURES...BUT STILL
ENOUGH DIFFERENCES THAT CONFIDENCE IS LOW WITH DETAILS.

WEST COAST TROUGH WILL GRADUALLY PROPAGATE EAST WITH MULTIPLE
SHORTWAVES EJECTING INTO THE REGION. HARD TO PINPOINT EXACTLY WHEN
AND WHERE THE BEST THUNDER CHANCES WILL BE...BUT THE MODELS DO
OFFER A COUPLE STRONGER SIGNALS. THE FIRST BEST CHANCE IS TONIGHT
INTO SATURDAY MORNING AS MENTIONED IN THE PREVIOUS AFD (1243PM).
18Z HRRR DOES INDICATE A THUNDERSTORM COMPLEX MOVING INTO THE
SOUTHERN FA AFTER 06Z...ALONG WITH WITH ISOLATED STRONGER STORMS.
THIS COMPLEX SHOULD MOVE THROUGH FAIRLY QUICKLY...WITH UP TO 0.5
INCH AREAL QPF POSSIBLE.

THINKING THERE WILL BE A BRIEF BREAK IN ACTIVITY ON SATURDAY.
SEVERE POTENTIAL WILL DEPEND ON HOW FAR NORTH THE SURFACE WARM
FRONT WILL MAKE IT BY SATURDAY AFTERNOON. THE GEM/GFS BRING THIS
FEATURE MUCH FURTHER NORTH THAN OTHER MODELS (LIKELY BECAUSE THEY
ARE STRONGER WITH A SHORTWAVE INTO SOUTHERN CANADA). AT ANY
RATE...GIVEN THIS TIME OF YEAR WITHOUT EVAPOTRANSPIRATION...THE
NAM SEEMS TO HAVE THE CORRECT IDEA INDICATING MLCAPE 1000-1500
J/KG WITHIN THE WARM SECTOR. THIS INSTABILITY ALONG WITH DEEP
LAYER SHEAR 30-35 KNOTS SHOULD BE ENOUGH FOR LIMITED SEVERE
POTENTIAL WITHIN THE WARM SECTOR AS THE COLD FRONT SLOWLY
PROPAGATES EAST INTO THE EVENING HOURS.

THE BEST CHANCE FOR FLASH FLOODING POTENTIAL WOULD BE SATURDAY
EVENING AND OVERNIGHT ALONG THE SLOW MOVING BOUNDARY. THE BIGGEST
QUESTIONS AT THIS POINT WILL BE THE EXACT LOCATION OF THIS
FEATURE...AND HOW QUICKLY IT WILL MOVE TO THE EAST. NOT ENOUGH
CONFIDENCE FOR A FLASH FLOOD WATCH AT THIS POINT...BUT THERE IS A
SLIGHT RISK FOR FLASH FLOODING ALONG AND EAST OF THE VALLEY.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 PM CDT FRI MAY 17 2013

SUNDAY-MONDAY...UPPER LOW WILL CLOSE OFF JUST SOUTH OF THE FA AND
BRING PERIODIC SHOWERS AND THUNDERSTORMS TO THE REGION.
INSTABILITY IS MUCH WEAKER BY THIS TIME...BUT GIVEN HIGH PWATS AN
ADDITIONAL 1-2 INCHES OF RAINFALL IS POSSIBLE (ESPECIALLY THE
SOUTHERN HALF OF THE FA). THIS RAINFALL WOULD OVER A COUPLE DAYS
AND ANY FLOOD THREAT IS DEPENDENT ON WHAT OCCURS SATURDAY/SATURDAY
NIGHT.

MONDAY NIGHT-FRIDAY...12Z GFS/12Z ECMWF IN PRETTY GOOD AGREEMENT
IN SHOWING THE 500 MB LOW OVER EASTERN SD/MN REGION TUESDAY THEN
DRIFTING A BIT SOUTH AND EAST WEDNESDAY AND THEN EAST OF THE AREA
THURSDAY. LOOK FOR A CONTINUED HIGH THREAT FOR SHOWERS
TUESDAY...DIMINISHING ON WEDNESDAY. A 500 MB RIDGE WILL BUILD IN
BEHIND THE LOW FOR THE END OF THE WEEK WITH DRY WEATHER RETURNING.
LOOK FOR TEMPS TO BIT A BIT BELOW NORMAL WITH THE CLOUDS/RAIN TUE-
WED THEN RETURN TO CLOSE TO NORMAL LEVELS BY LATE WEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 652 PM CDT FRI MAY 17 2013

VFR CLOUDS WILL CONTINUE OVER MUCH OF THE AREA...BUT SOME MVFR
CEILINGS OVER THE SOUTHEASTERN FORECAST AREA WILL BEGIN TO SPREAD
NORTH AND WEST LATER ON TONIGHT. HAVE KFAR DECREASING TO MVFR
AFTER MIDNIGHT AND THE OTHER SITES MORE TOWARDS MORNING. SHOWERS
AND A FEW THUNDERSTORMS WILL MOVE IN AFTER MIDNIGHT...WITH THE
BEST CONVECTION IN THE SOUTH AROUND KFAR WHILE THE NORTHERN SITES
WILL BE MORE SHOWERY. WINDS WILL SHIFT TO A MORE SOUTHERLY
DIRECTION DURING THE DAY TOMORROW AS A WARM FRONT LIFTS NORTH INTO
THE AREA...ALTHOUGH THERE IS STILL SOME UNCERTAINTY AS TO EXACTLY
WHERE THE BOUNDARY WILL END UP. FOR NOW HAVE IT GOING PAST OUR
NORTHERN TAF SITES BY LATE IN THE PERIOD BUT THE BOUNDARY MAY
STALL OUT AND LEAVE THEM IN EASTERLY WINDS AND MORE RAIN. THINK
THAT THERE SHOULD BE SOME BRIEF IMPROVEMENT TO VFR IN MOST SITES
DURING THE LATE MORNING OR AFTERNOON ALTHOUGH MUCH WILL DEPEND ON
HOW EARLY MORNING CONVECTION PLAYS OUT.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/RIDDLE
AVIATION...JR

000
FXUS63 KFGF 172045
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
345 PM CDT FRI MAY 17 2013

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 330 PM CDT FRI MAY 17 2013

THE MAIN CONCERNS WILL BE HEAVY RAIN AND SEVERE POTENTIAL. 12Z
MODELS IN DECENT AGREEMENT WITH SYNOPTIC FEATURES...BUT STILL
ENOUGH DIFFERENCES THAT CONFIDENCE IS LOW WITH DETAILS.

WEST COAST TROUGH WILL GRADUALLY PROPAGATE EAST WITH MULTIPLE
SHORTWAVES EJECTING INTO THE REGION. HARD TO PINPOINT EXACTLY WHEN
AND WHERE THE BEST THUNDER CHANCES WILL BE...BUT THE MODELS DO
OFFER A COUPLE STRONGER SIGNALS. THE FIRST BEST CHANCE IS TONIGHT
INTO SATURDAY MORNING AS MENTIONED IN THE PREVIOUS AFD (1243PM).
18Z HRRR DOES INDICATE A THUNDERSTORM COMPLEX MOVING INTO THE
SOUTHERN FA AFTER 06Z...ALONG WITH WITH ISOLATED STRONGER STORMS.
THIS COMPLEX SHOULD MOVE THROUGH FAIRLY QUICKLY...WITH UP TO 0.5
INCH AREAL QPF POSSIBLE.

THINKING THERE WILL BE A BRIEF BREAK IN ACTIVITY ON SATURDAY.
SEVERE POTENTIAL WILL DEPEND ON HOW FAR NORTH THE SURFACE WARM
FRONT WILL MAKE IT BY SATURDAY AFTERNOON. THE GEM/GFS BRING THIS
FEATURE MUCH FURTHER NORTH THAN OTHER MODELS (LIKELY BECAUSE THEY
ARE STRONGER WITH A SHORTWAVE INTO SOUTHERN CANADA). AT ANY
RATE...GIVEN THIS TIME OF YEAR WITHOUT EVAPOTRANSPIRATION...THE
NAM SEEMS TO HAVE THE CORRECT IDEA INDICATING MLCAPE 1000-1500
J/KG WITHIN THE WARM SECTOR. THIS INSTABILITY ALONG WITH DEEP
LAYER SHEAR 30-35 KNOTS SHOULD BE ENOUGH FOR LIMITED SEVERE
POTENTIAL WITHIN THE WARM SECTOR AS THE COLD FRONT SLOWLY
PROPAGATES EAST INTO THE EVENING HOURS.

THE BEST CHANCE FOR FLASH FLOODING POTENTIAL WOULD BE SATURDAY
EVENING AND OVERNIGHT ALONG THE SLOW MOVING BOUNDARY. THE BIGGEST
QUESTIONS AT THIS POINT WILL BE THE EXACT LOCATION OF THIS
FEATURE...AND HOW QUICKLY IT WILL MOVE TO THE EAST. NOT ENOUGH
CONFIDENCE FOR A FLASH FLOOD WATCH AT THIS POINT...BUT THERE IS A
SLIGHT RISK FOR FLASH FLOODING ALONG AND EAST OF THE VALLEY.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 330 PM CDT FRI MAY 17 2013

SUNDAY-MONDAY...UPPER LOW WILL CLOSE OFF JUST SOUTH OF THE FA AND
BRING PERIODIC SHOWERS AND THUNDERSTORMS TO THE REGION.
INSTABILITY IS MUCH WEAKER BY THIS TIME...BUT GIVEN HIGH PWATS AN
ADDITIONAL 1-2 INCHES OF RAINFALL IS POSSIBLE (ESPECIALLY THE
SOUTHERN HALF OF THE FA). THIS RAINFALL WOULD OVER A COUPLE DAYS
AND ANY FLOOD THREAT IS DEPENDENT ON WHAT OCCURS SATURDAY/SATURDAY
NIGHT.

MONDAY NIGHT-FRIDAY...12Z GFS/12Z ECMWF IN PRETTY GOOD AGREEMENT
IN SHOWING THE 500 MB LOW OVER EASTERN SD/MN REGION TUESDAY THEN
DRIFTING A BIT SOUTH AND EAST WEDNESDAY AND THEN EAST OF THE AREA
THURSDAY. LOOK FOR A CONTINUED HIGH THREAT FOR SHOWERS
TUESDAY...DIMINISHING ON WEDNESDAY. A 500 MB RIDGE WILL BUILD IN
BEHIND THE LOW FOR THE END OF THE WEEK WITH DRY WEATHER RETURNING.
LOOK FOR TEMPS TO BIT A BIT BELOW NORMAL WITH THE CLOUDS/RAIN TUE-
WED THEN RETURN TO CLOSE TO NORMAL LEVELS BY LATE WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1243 PM CDT FRI MAY 17 2013

QUESTION FOR THIS PERIOD WILL BE HOW FAR NORTH THE MVFR CLOUDS
SPREAD DURING THE NIGHT INTO SATURDAY MORNING AND PRECIPITATION
(THUNDER) CHANCES.  THRU 00Z FORSEE ALL SITES STAYING VFR..BUT
WATCHING AN AREA OF HIGHER DEW POINTS ALONG WITH 25-35K FT CLOUD
DECK MOVING SLOWLY NORTHWEST FROM WCNTRL MN AND ECNTRL SD.  TIMING
OF THIS MOVEMENT NORTHWEST INTO FARGO AREA IS SUSPECT...BUT LATEST
RAP MODEL SUGGEST 03Z-06Z PERIOD.  THESE CONDITIONS MAY REACH THE
OTHER TAF SITES TOWARD 12Z.  PRECIP (THUNDER) CHANCES LATER TONIGHT
INTO SATURDAY MORNING AND WHEN/HOW IT AFFECTS ANY TAF SITE IS QUITE
DIFFICULT TO DETERMINE NOW.  FOR NOW JUST INCLUDED A TEMPO GROUP FOR
FARGO AS BEST CHANCE APPEARS THERE OVERNIGHT.  WINDS WILL REMAIN
SOUTHEAST MOSTLY 10 TO 20 KTS.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

SHORT TERM...TG
LONG TERM...TG/RIDDLE
AVIATION...RIDDLE

000
FXUS63 KBIS 171959
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
259 PM CDT FRI MAY 17 2013

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 258 PM CDT FRI MAY 17 2013

THE MAIN SHORT TERM FOCUS IS PRECIPITATION THROUGH SATURDAY.

PRECIPITATION CHANCES HAVE GENERALLY BEEN LOWERED FROM CONTINUITY
BASED ON MODEL CONSENSUS AND COORDINATION WITH SURROUNDING
OFFICES. THEY NOW REFLECT THE BEST CHANCES FOR SHOWERS AND
THUNDERSTORMS. UNFORTUNATELY...THE AVAILABLE 12 UTC THROUGH 18 UTC
GUIDANCE DISAGREES WITH TIMING AND COVERAGE ACROSS MUCH OF THE
STATE FOR THIS AFTERNOON AND TONIGHT...BUT THERE IS GENERAL
AGREEMENT THAT AN AREA OF CONVECTION WILL DEVELOP OVER
SOUTHEASTERN MONTANA THIS AFTERNOON AND MOVE EAST-NORTHEAST.

WATER VAPOR SATELLITE IMAGERY INDICATES THE LEADING EDGE OF THE
NEXT MID LEVEL SHORTWAVE WILL NOSE INTO SOUTHWESTERN NORTH DAKOTA
AROUND 23 UTC. WHILE THAT WILL LIKELY BE THE BEST CHANCE FOR
STRONGER THUNDERSTORMS...CURRENT RADAR CONFIRMS THAT SHOWERS AHEAD
OF THAT FEATURE WILL ALSO SPREAD ACROSS THE MISSOURI SLOPE THIS
AFTERNOON...THOUGH NO LIGHTENING HAS BEEN OBSERVED THERE. LOOK
FOR THIS TREND TO CONTINUE AND FILL IN THROUGH THE AFTERNOON AS
MORE FAVORABLE DYNAMIC FORCING MOVES INTO THE REGION.

THERE IS A SPC SLIGHT RISK FOR SEVERE THUNDERSTORMS ON SATURDAY
AFTERNOON ASSOCIATED WITH A DEEPENING SURFACE LOW. NORTH DAKOTA
LOOKS TO BE ON THE NORTH SIDE OF THE WARM FRONT. WHILE LOW-LEVEL
WINDS WILL BE BACKED...FORECAST CLOUD COVER JUSTIFIED MODEL
SOUNDINGS NOT FAVORABLE FOR SURFACE-BASED CONVECTION. THUS...THE
MAIN THREATS WILL BE LARGE HAIL AND DAMAGING WINDS UNLESS CLEARING
MOVES INTO SOUTH CENTRAL NORTH DAKOTA.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 258 PM CDT FRI MAY 17 2013

THE MAIN FORECAST HIGHLIGHT FOR THE EXTENDED PERIOD CONTINUES TO BE
THE MODERATE TO HEAVY RAIN EVENT THROUGH EARLY TUESDAY.

THE 12Z DETERMINISTIC MODEL SUITE IS IN GOOD AGREEMENT EARLY IN THE
EXTENDED PERIOD BEFORE SOLUTIONS DIVERGE IN REGARDS OF THE FORMATION
AND MOVEMENT OF THE UPPER LEVEL LOW ACROSS THE NORTHERN PLAINS
MONDAY THROUGH WEDNESDAY. A BROAD WESTERN CONUS UPPER LEVEL TROUGH
IS PROGGED TO PUSH EAST AND OVER THE PLAINS SATURDAY AND
SUNDAY...CLOSE OFF OVER THE NORTHERN AND CENTRAL PLAINS LATE SUNDAY
AND MONDAY...AND THEN SLOWLY PUSH EAST AND WEAKEN THROUGH THURSDAY.
THE 12Z GFS REMAINS THE PROGRESSIVE SOLUTION MOVING AND WEAKENING
THE CLOSED OFF LOW AWAY FROM THE DAKOTAS BY WEDNESDAY...WHILE THE
12Z ECWMF/GEM KEEPS IT MEANDERING OVER THE DAKOTAS BEFORE PUSHING
EAST AND WEAKENING BY LATE NEXT WEEK. MEANWHILE...A REX BLOCKING
PATTERN OVER NORTHERN AMERICA WILL BEGIN TO SET UP AS UPPER LEVEL
RIDGING TAKES PLACE NORTH OF THE AFOREMENTIONED CLOSED OFF LOW AND
ANOTHER TROUGH DROPS SOUTH FROM THE NORTHEASTERN PACIFIC.

AS A RESULT IN THE DIFFERENCES IN THE POSITIONING AND MOVEMENT OF THE
AFOREMENTIONED LOW...PLACEMENT AND AMOUNT OF PRECIPITATION DIFFER
BETWEEN THE GFS AND THE GEM/ECWMF SOLUTIONS...MOST NOTABLY ON MONDAY
AND TUESDAY. THE ECWMF/GEM CONTINUE CHANCES FOR PRECIPITATION ON
THESE DAYS AS THE LOW HOVERS OVERHEAD...WHILE THE GFS KEEPS MOST OF
THE NORTH AND WEST DRY...WITH PRECIPITATION CHANCES FOR THE
SOUTHEAST PART OF THE STATE. HAVE DECIDED TO STICK CLOSE TO WPC
GUIDANCE FOR QPF...WHICH KEEPS THE JAMES RIVER VALLEY ON TRACK FOR
ONE TO TWO INCHES OF RAINFALL FROM SATURDAY EVENING THROUGH
TUESDAY...WITH LESSER AMOUNTS FURTHER NORTHWEST. IN REGARDS TO ANY
POTENTIAL FLOODING ISSUES...CONDITIONS ARE SUCH THAT SOILS CAN
ABSORB SIGNIFICANT RAINFALL. THUS...SIGNIFICANT RISES ON MAIN STEM
RIVERS SUCH AS THE SOURIS AND JAMES ARE NOT EXPECTED.
HOWEVER...ENHANCED RAINFALL RATES OR SEVERAL ROUNDS OF STORMS COULD
PRODUCE LOCALIZED RUNOFF...LEADING TO RISES ON SMALL CREEKS AND
STREAMS...AND POSSIBLY FLASH FLOODING.

PRECIPITATION CHANCES WILL BEGIN TO DIMINISH LATE TUESDAY AND INTO
WEDNESDAY AS DRY AND SEASONABLE CONDITIONS TAKE OVER....WITH AN
ADDITIONAL CHANCE FOR SHOWERS POSSIBLY THURSDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 227 PM CDT FRI MAY 17 2013

VFR CONDITIONS AT ALL TAF SITES WILL EVENTUALLY BECOME MVFR
TONIGHT AS WIDESPREAD SHOWERS AND THUNDERSTORMS ACCOMPANY LOWER
CEILINGS. THE OFFENDING LARGE LOW PRESSURE SYSTEM WILL REMAIN OVER
THE NORTHERN PLAINS THROUGH AT LEAST MONDAY. THUNDERSTORMS WILL BE
MORE WIDESPREAD SATURDAY AFTERNOON AND EVENING.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...SCHECK
LONG TERM...LTH
AVIATION...SCHECK

000
FXUS63 KBIS 171833
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
133 PM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 114 PM CDT FRI MAY 17 2013

THE MAIN FOCUS THIS UPDATE WAS PRECIPITATION CHANCES TODAY AND
TONIGHT.

BASED ON MODEL CONSENSUS AND COORDINATION WITH SURROUNDING
OFFICES...PROBABILITIES WERE SCALED BACK TO BETTER REFLECT THE
BEST CHANCES FOR SHOWERS AND THUNDERSTORMS. UNFORTUNATELY...THE
AVAILABLE 12 UTC THROUGH 16 UTC GUIDANCE DISAGREES WITH
TIMING...BUT THERE IS GENERAL AGREEMENT THAT AN AREA OF CONVECTION
WILL DEVELOP OVER SOUTHEASTERN MONTANA THIS AFTERNOON AND MOVE
NORTHEASTWARD. TIMING THE NEXT MID-LEVEL SHORTWAVE USING WATER
VAPOR SATELLITE IMAGERY INDICATES THE LEADING EDGE OF DYNAMIC
FORCING WILL SPREAD INTO SOUTHWESTERN NORTH DAKOTA AROUND 23 UTC.
WHILE THAT WILL LIKELY BE THE BEST CHANCE FOR STRONGER
THUNDERSTORMS...CURRENT RADAR AND VISIBLE SATELLITE SHOW THAT SOME
DESTABILIZATION HAS ALREADY OCCURRED...THOUGH NO LIGHTENING HAS
BEEN OBSERVED.

LOOK FOR THIS TREND TO CONTINUE AND FILL IN THROUGH THE AFTERNOON
AS MORE FAVORABLE DYNAMIC FORCING MOVES INTO THE REGION.

UPDATE ISSUED AT 1001 AM  CDT FRI MAY 17 2013

THE MAIN FOCUS TODAY WILL BE SEEMINGLY UNENDING PRECIPITATION
CHANCES. THIS UPDATE MADE SIMPLE ADJUSTMENTS TO PRECIPITATION
PROBABILITIES TODAY. WHILE THERE LOOKS TO BE A BREAK THAT WILL
LAST SEVERAL HOURS OVER MUCH OF THE MISSOURI SLOPE AND JAMES RIVER
VALLEYS THROUGH EARLY AFTERNOON...ECHOES ON SOUTH DAKOTA RADARS
INDICATE AT LEAST LIGHT SHOWER ACTIVITY MOVING NORTHEASTWARD FAST.
THE NEXT FEW HOURS SHOULD GIVE A BETTER FEEL FOR FORCING
MECHANISMS AND LIKELIHOOD OF INTENSIFICATION.

PREVIOUS FORECASTS OF SUB-SEVERE CONVECTION OVER SOUTHWESTERN NORTH
DAKOTA LOOK TO BE ON TRACK FOR LATER TODAY/TONIGHT.

UPDATE ISSUED AT 637 AM CDT FRI MAY 17 2013

UPDATE FOR MINOR CHANGES TO POPS ACROSS THE NORTH THIS MORNING AS
BATCH OF SHOWERS AND ISOLATED THUNDERSTORMS CONTINUES TO HEAD
NORTHEAST. OTHERWISE...MAINTAINED GENERALLY INCREASING POPS
THROUGH LATE AFTERNOON AND EVENING.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM CDT FRI MAY 17 2013

THE MAIN CONCERN FOR TODAY INTO TONIGHT WILL BE THE CHANCE OF
THUNDERSTORMS AND POTENTIAL SEVERE WEATHER. EARLY MORNING RADAR
MOSAIC SHOWED ISOLATED SHOWERS FROM SOUTHWEST NORTH DAKOTA INTO
NORTHWEST MINNESOTA. MUCH OF THIS ACTIVITY DEVELOPED IN AN AREA OF
H85 WARM AIR ADVECTION THAT HAS BEEN MOVING FROM SOUTH TO NORTH
ACROSS THE REGION. THE STRONGEST WARM AIR ADVECTION SHIFTS NORTH BY
AFTERNOON AS SOUTHWESTERLY FLOW ALOFT BRINGS A SERIES OF WAVES ACROSS
THE STATE. WILL MAINTAIN FAIRLY HIGH POPS TODAY...ESPECIALLY IN
THE NORTH AND WEST WHERE THE MAJORITY OF MODEL SOLUTIONS FAVOR THE
HIGHER PRECIPITATION CHANCES.

THE FOCUS THEN TURNS FARTHER SOUTH AS SURFACE LOW PRESSURE GATHERS
IN EAST CENTRAL WYOMING. A WARM FRONT STRETCHING OUT OF THE LOW
INTO SOUTHERN SOUTH DAKOTA IS EXPECTED TO LIFT NORTH TONIGHT...BRINGING
INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS TO CENTRAL AND
WESTERN NORTH DAKOTA. CAN NOT RULE OUT AN ISOLATED SEVERE STORM
LATE THIS AFTERNOON / EVENING ACROSS THE SOUTHERN PART OF THE
FORECAST AREA WHERE INSTABILITY WILL BE GREATEST. THE SPC DAY 1
SEVERE WEATHER OUTLOOK KEEPS THE SLIGHT RISK SOUTH OF THE FORECAST
AREA...HOWEVER THE 5 PERCENT PROBABILITIES FOR SEVERE HAIL / WIND
ARE DRAWN SOUTH OF I-94 INTO SOUTHERN NORTH DAKOTA WHICH APPEARS
REASONABLE.

TEMPERATURES TODAY WILL BE TRICKY DUE TO THE CLOUDS AND RAIN. WILL
GENERALLY STAY ON THE COOL SIDE OF GUIDANCE WHICH SUGGESTS MID
60S NORTH TO LOWER 70S SOUTH.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 349 AM CDT FRI MAY 17 2013

THE MAIN FORECAST ISSUES THROUGH THE LONG TERM PERIOD ARE CONVECTIVE
TRENDS...AND POTENTIAL FOR PROLONGED MODERATE TO HEAVY RAIN AND
SOME SEVERE WEATHER ON SATURDAY. THE LATEST 17/00Z MODEL RUNS HAVE
SOME SIGNIFICANT DIFFERENCE IN THE PROGRESSION OF A CLOSED UPPER
LOW THROUGH THE REGION THROUGH EARLY NEXT WEEK. THE NAM IS AMONG
THE FARTHEST WEST...WHILE THE GFS FAVORS A FASTER...MORE EASTERLY
PATH. THE ECMWF REPRESENTS A REASONABLE COMPROMISE...AND WOULD
KEEP SHOWERS AROUND INTO TUESDAY BEFORE PUSHING EAST. THE FAVORED
PERIOD FOR SEVERE WEATHER WILL BE SATURDAY...WITH SOUTHWEST FLOW
ALOFT AND A WARM FRONT NOSING INTO THE SOUTHEAST PORTION OF THE
FORECAST AREA. SPC CONTINUES TO HAVE THE SOUTHEAST OUTLOOKED IN
SLIGHT RISK FOR DAY 2. BUFR SOUNDINGS SUGGEST STORMS WILL DEVELOP
RELATIVELY EARLY IN THE DAY. AM EXPECTING SOME STRONG TO SEVERE
STORMS WITH LARGE HAIL/STRONG WIND GUSTS THE PRIMARY THREATS.
STRONG MOISTURE TRANSPORT INTO THE BOUNDARY WILL CONTINUE THROUGH
SATURDAY NIGHT AS A DECENT SHORT WAVE TROUGH MOVES THROUGH EASTERN
NORTH DAKOTA. THE SEVERE WEATHER THREAT DIMINISHES SUNDAY...BUT
MODERATE TO LOCALLY HEAVY RAIN IS EXPECTED TO CONTINUE OVER MUCH
OF WESTERN AND CENTRAL NORTH DAKOTA. THIS SCENARIO WILL LIKELY
CONTINUE MONDAY...BEFORE SHOWERS TAPER OFF IN COVERAGE AND
INTENSITY ON TUESDAY. TOTAL RAINFALL AMOUNTS OF 1 TO 3 ARE
EXPECTED THROUGH THE PERIOD...WITH AMOUNTS AROUND 4 INCHES
POSSIBLE...ESPECIALLY IN THE JAMES RIVER VALLEY. CONDITIONS ARE
SUCH THAT SOILS CAN ABSORB SIGNIFICANT RAINFALL. THUS...SIGNIFICANT
RISES ON MAIN STEM RIVERS SUCH AS THE SOURIS AND JAMES ARE NOT
EXPECTED. HOWEVER...ENHANCED RAINFALL RATES OR SEVERAL ROUNDS OF
STORMS COULD PRODUCE LOCALIZED RUNOFF...LEADING TO RISES ON SMALL
CREEKS AND STREAMS...AND POSSIBLY FLASH FLOODING.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 114 PM CDT FRI MAY 17 2013

VFR CONDITIONS AT ALL TAF SITES WILL EVENTUALLY BECOME MVFR
TONIGHT AS WIDESPREAD SHOWERS AND THUNDERSTORMS ACCOMPANY LOWER
CEILINGS. THE OFFENDING LARGE LOW PRESSURE SYSTEM WILL REMAIN OVER
THE NORTHERN PLAINS THROUGH AT LEAST MONDAY. THUNDERSTORMS WILL BE
MORE WIDESPREAD SATURDAY AFTERNOON AND EVENING.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE/AVIATION...SCHECK
SHORT TERM...CK
LONG TERM...RP KINNEY

000
FXUS63 KFGF 171743
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
1243 PM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 1243 PM CDT FRI MAY 17 2013

SCATTERED SHOWERS ACROSS THE NW FA WILL EXIT BY LATER THIS
AFTERNOON AS ASSOCIATED UPPER WAVE PROPAGATES INTO CANADA.
CLEAR SKIES REMAIN ACROSS PORTIONS OF THE SOUTHERN FA...AND
TEMPERATURES WITHIN THIS AREA ARE NOW INTO THE 70S. THE TREND OF
BECOMING CLOUDY STILL LOOKS GOOD...BUT IT WILL TAKE SOME TIME.
INCREASED MAX TEMPS INTO THE MID-UPPER 70S WITHIN THE CLEAR
AREA...AND SLOWED DOWN THE PROGRESSION OF THIS AREA BECOMING
CLOUDY. THE OTHER ISSUE WILL BE THUNDER CHANCES TONIGHT. FOLLOWING
THE LATEST RAP/HRRR GUIDANCE AND 12Z NAM/GFS...THERE WILL BE A
SURGE OF INSTABILITY AS 850MB WINDS AND WARM AIR ADVECTION
INCREASE (ALONG ELEVATED WARM FRONT). THIS WILL HAPPEN CLOSER TO
03Z-06Z ACROSS THE SOUTHERN FA. THE RAP INDICATES 850MB CAPE ABOVE
1000 J/KG ALONG WITH AROUND 35 KNOTS OF DEEP LAYER SHEAR...WHICH
COULD POSSIBLY LEAD TO ISOLATED SEVERE HAIL (SEVERE HAIL POTENTIAL
IS DEPENDENT ON STRENGTH OF INSTABILITY). THIS COMPLEX WILL LIKELY
WEAKEN AS IT MOVES TO THE NORTH...BUT THUNDER/SHOWER CHANCES
SHOULD HOLD TOGETHER AND EXIT THE NORTHERN FA SATURDAY MORNING.
UPDATED THE GRIDS THROUGH TONIGHT FOR THIS THINKING (AND WILL
CONCENTRATE ON SATURDAY THROUGH MONDAY FOR THE NEXT FORECAST
ISSUANCE).

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 325 AM CDT FRI MAY 17 2013

FORECAST CHALLENGE CONCERNS PCPN CHANCES/AMOUNTS AND TEMPERATURES.
MODELS IN GENERAL AGREEMENT WITH MAIN FEATURES HOWEVER ALL DIFFER
ON QPF SCENARIOS THROUGH THE SHORT TERM. AT THIS POINT WILL USE A
GENERAL BLEND.

PERSISTENT BAND OF -SHRA ASSOCIATED WITH ELEVATED ZONE OF
ENHANCED WARM ADVECTION AND H7 CONVERGENCE SHOULD GRADUALLY WEAKEN
THROUGH THE MORNING AS ABOVE FEATURES WEAKEN AND SHIFT NE. WILL GO
WITH HIGH POP/LOW QPF INTO MID MORNING THEN TRIM BACK ON POPS.
ELSEWHERE CONFIDENCE LOW ON ANY PCPN POTENTIAL THROUGH THE BULK OF
THE DAY. SURFACE LOW AND E-W ORIENTED WARM FRONTAL BOUNDARY ALONG
SD/NE BORDER INTO IA LIFTS SLOWLY THROUGH SD DURING THE DAY.
EXPECT MOST PCPN WILL BE ORIENTED CLOSER TO LOW LEVEL BOUNDARY TO
OUR SOUTH. WILL INCREASE POPS SOMEWHAT LATER IN THE AFTERNOON AS
BOUNDARY APPROACHES. TEMPERATURES WILL BE HIGHLY INFLUENCED BY
CLOUDS. RAISED TEMPERATURES SLIGHTLY ACROSS THE SOUTH WHERE SOME
THINNER CLOUD COVER EXISTS OTHERWISE WILL STICK WITH PERSISTENCE.

AS WARM FRONT LIFTS NORTH TONIGHT EXPECT RAIN CHANCES TO INCREASE
AND BY MID EVENING SOUTHERN AND WESTERN FORECAST AREAS LOOK TO BE
FAVORED AREAS FOR SHRA/TSRA. BEST THUNDER POTENTIAL WILL BE ACROSS
THE SOUTH AS NORTHERN AREAS STILL PRETTY STABLE. BAND OF PCPN
SHOULD LIFT NORTHWARD OVERNIGHT NIGHT AND ADJUSTED POPS
ACCORDINGLY.

FRONTAL BOUNDARY WILL BE ORIENTED ACROSS FA SATURDAY SO INCREASED
POPS. SEVERE POTENTIAL LOOKS BEST LATE IN THE AFTERNOON ACROSS THE
SOUTH HALF OF THE FA WITH FAVORABLE CONVECTIVE PARAMETERS.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI MAY 17 2013

SEVERE CONVECTIVE THREAT WILL CONTINUE INTO THE EVENING. WITH
PRECIPITABLE H2O VALUES AROUND 1.5 INCHES HEAVY RAIN WILL BE A
POSSIBILITY. INITIALLY FAVORED AREA FOR HEAVY RAIN LOOKS TO BE
ACROSS S HALF OF FA LIFTING NORTHWARD DURING THE OVERNIGHT.

WITH CUT OFF LOW DEVELOPING VCNTY OF FA POTENTIAL FOR SIGNIFICANT
RAIN WILL CONTINUE THROUGH THE WEEKEND AND WILL NEED TO MONITOR
RAIN AMOUNTS CLOSELY. AT THIS POINT LONG DURATION RAIN EVENT FOR
SURE BUT NOT ENOUGH CONFIDENCE ON ANY PARTICULAR LOCATION FOR
FLOOD/FLASH FLOOD WATCH.

0 UTC GFS/ECMWF/GEM IN GOOD OVERALL AGREEMENT NEXT WEEK...SHOWING A
CLOSED 500 HPA LOW ACROSS SOUTHEAST SD MONDAY MORNING CRAWLING
PAINFULLY SLOW TO THE EAST THROUGH WEDNESDAY. THIS FIRMLY ENTRENCHES
THE FORECAST AREA IN WRAP-AROUND RAIN SHOWERS THROUGH TUESDAY...
SLOWLY DRYING OUT WEDNESDAY AND A RETURN TO DRY CONDITIONS ON THURSDAY.
WILL KEEP THUNDER MENTION THROUGH MONDAY...BUT MOST INSTABILITY
SHOULD MOVE TO THE SOUTH BY TUESDAY. WITH CLOUD COVER AND RAIN...
TEMPERATURES WILL BE NEAR OR SLIGHTLY BELOW MID-MAY NORMALS WITH
HIGHS IN THE UPPER 50S AND 60S AND LOWS IN THE 40S/LOWER 50S. WITH
GREATER SUNSHINE AND DRY CONDITIONS...SHOULD SEE SOME AREAS REACHING
70 DEGREES BY THURSDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1243 PM CDT FRI MAY 17 2013

QUESTION FOR THIS PERIOD WILL BE HOW FAR NORTH THE MVFR CLOUDS
SPREAD DURING THE NIGHT INTO SATURDAY MORNING AND PRECIPITATION
(THUNDER) CHANCES.  THRU 00Z FORSEE ALL SITES STAYING VFR..BUT
WATCHING AN AREA OF HIGHER DEW POINTS ALONG WITH 25-35K FT CLOUD
DECK MOVING SLOWLY NORTHWEST FROM WCNTRL MN AND ECNTRL SD.  TIMING
OF THIS MOVEMENT NORTHWEST INTO FARGO AREA IS SUSPECT...BUT LATEST
RAP MODEL SUGGEST 03Z-06Z PERIOD.  THESE CONDITIONS MAY REACH THE
OTHER TAF SITES TOWARD 12Z.  PRECIP (THUNDER) CHANCES LATER TONIGHT
INTO SATURDAY MORNING AND WHEN/HOW IT AFFECTS ANY TAF SITE IS QUITE
DIFFICULT TO DETERMINE NOW.  FOR NOW JUST INCLUDED A TEMPO GROUP FOR
FARGO AS BEST CHANCE APPEARS THERE OVERNIGHT.  WINDS WILL REMAIN
SOUTHEAST MOSTLY 10 TO 20 KTS.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...TG
SHORT TERM...VOELKER
LONG TERM...VOELKER/ROGERS
AVIATION...RIDDLE

000
FXUS63 KBIS 171506
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
1006 AM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 1001 AM  CDT FRI MAY 17 2013

THE MAIN FOCUS TODAY WILL BE SEEMINGLY UNENDING PRECIPITATION
CHANCES. THIS UPDATE MADE SIMPLE ADJUSTMENTS TO PRECIPITATION
PROBABILITIES TODAY. WHILE THERE LOOKS TO BE A BREAK THAT WILL
LAST SEVERAL HOURS OVER MUCH OF THE MISSOURI SLOPE AND JAMES RIVER
VALLEYS THROUGH EARLY AFTERNOON...ECHOES ON SOUTH DAKOTA RADARS
INDICATE AT LEAST LIGHT SHOWER ACTIVITY MOVING NORTHEASTWARD FAST.
THE NEXT FEW HOURS SHOULD GIVE A BETTER FEEL FOR FORCING
MECHANISMS AND LIKELIHOOD OF INTENSIFICATION.

PREVIOUS FORECASTS OF SUB-SEVERE CONVECTION OVER SOUTHWESTERN NORTH
DAKOTA LOOK TO BE ON TRACK FOR LATER TODAY/TONIGHT.

UPDATE ISSUED AT 637 AM CDT FRI MAY 17 2013

UPDATE FOR MINOR CHANGES TO POPS ACROSS THE NORTH THIS MORNING AS
BATCH OF SHOWERS AND ISOLATED THUNDERSTORMS CONTINUES TO HEAD
NORTHEAST. OTHERWISE...MAINTAINED GENERALLY INCREASING POPS
THROUGH LATE AFTERNOON AND EVENING.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM CDT FRI MAY 17 2013

THE MAIN CONCERN FOR TODAY INTO TONIGHT WILL BE THE CHANCE OF
THUNDERSTORMS AND POTENTIAL SEVERE WEATHER. EARLY MORNING RADAR
MOSAIC SHOWED ISOLATED SHOWERS FROM SOUTHWEST NORTH DAKOTA INTO
NORTHWEST MINNESOTA. MUCH OF THIS ACTIVITY DEVELOPED IN AN AREA OF
H85 WARM AIR ADVECTION THAT HAS BEEN MOVING FROM SOUTH TO NORTH
ACROSS THE REGION. THE STRONGEST WARM AIR ADVECTION SHIFTS NORTH BY
AFTERNOON AS SOUTHWESTERLY FLOW ALOFT BRINGS A SERIES OF WAVES ACROSS
THE STATE. WILL MAINTAIN FAIRLY HIGH POPS TODAY...ESPECIALLY IN
THE NORTH AND WEST WHERE THE MAJORITY OF MODEL SOLUTIONS FAVOR THE
HIGHER PRECIPITATION CHANCES.

THE FOCUS THEN TURNS FARTHER SOUTH AS SURFACE LOW PRESSURE GATHERS
IN EAST CENTRAL WYOMING. A WARM FRONT STRETCHING OUT OF THE LOW
INTO SOUTHERN SOUTH DAKOTA IS EXPECTED TO LIFT NORTH TONIGHT...BRINGING
INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS TO CENTRAL AND
WESTERN NORTH DAKOTA. CAN NOT RULE OUT AN ISOLATED SEVERE STORM
LATE THIS AFTERNOON / EVENING ACROSS THE SOUTHERN PART OF THE
FORECAST AREA WHERE INSTABILITY WILL BE GREATEST. THE SPC DAY 1
SEVERE WEATHER OUTLOOK KEEPS THE SLIGHT RISK SOUTH OF THE FORECAST
AREA...HOWEVER THE 5 PERCENT PROBABILITIES FOR SEVERE HAIL / WIND
ARE DRAWN SOUTH OF I-94 INTO SOUTHERN NORTH DAKOTA WHICH APPEARS
REASONABLE.

TEMPERATURES TODAY WILL BE TRICKY DUE TO THE CLOUDS AND RAIN. WILL
GENERALLY STAY ON THE COOL SIDE OF GUIDANCE WHICH SUGGESTS MID
60S NORTH TO LOWER 70S SOUTH.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 349 AM CDT FRI MAY 17 2013

THE MAIN FORECAST ISSUES THROUGH THE LONG TERM PERIOD ARE CONVECTIVE
TRENDS...AND POTENTIAL FOR PROLONGED MODERATE TO HEAVY RAIN AND
SOME SEVERE WEATHER ON SATURDAY. THE LATEST 17/00Z MODEL RUNS HAVE
SOME SIGNIFICANT DIFFERENCE IN THE PROGRESSION OF A CLOSED UPPER
LOW THROUGH THE REGION THROUGH EARLY NEXT WEEK. THE NAM IS AMONG
THE FARTHEST WEST...WHILE THE GFS FAVORS A FASTER...MORE EASTERLY
PATH. THE ECMWF REPRESENTS A REASONABLE COMPROMISE...AND WOULD
KEEP SHOWERS AROUND INTO TUESDAY BEFORE PUSHING EAST. THE FAVORED
PERIOD FOR SEVERE WEATHER WILL BE SATURDAY...WITH SOUTHWEST FLOW
ALOFT AND A WARM FRONT NOSING INTO THE SOUTHEAST PORTION OF THE
FORECAST AREA. SPC CONTINUES TO HAVE THE SOUTHEAST OUTLOOKED IN
SLIGHT RISK FOR DAY 2. BUFR SOUNDINGS SUGGEST STORMS WILL DEVELOP
RELATIVELY EARLY IN THE DAY. AM EXPECTING SOME STRONG TO SEVERE
STORMS WITH LARGE HAIL/STRONG WIND GUSTS THE PRIMARY THREATS.
STRONG MOISTURE TRANSPORT INTO THE BOUNDARY WILL CONTINUE THROUGH
SATURDAY NIGHT AS A DECENT SHORT WAVE TROUGH MOVES THROUGH EASTERN
NORTH DAKOTA. THE SEVERE WEATHER THREAT DIMINISHES SUNDAY...BUT
MODERATE TO LOCALLY HEAVY RAIN IS EXPECTED TO CONTINUE OVER MUCH
OF WESTERN AND CENTRAL NORTH DAKOTA. THIS SCENARIO WILL LIKELY
CONTINUE MONDAY...BEFORE SHOWERS TAPER OFF IN COVERAGE AND
INTENSITY ON TUESDAY. TOTAL RAINFALL AMOUNTS OF 1 TO 3 ARE
EXPECTED THROUGH THE PERIOD...WITH AMOUNTS AROUND 4 INCHES
POSSIBLE...ESPECIALLY IN THE JAMES RIVER VALLEY. CONDITIONS ARE
SUCH THAT SOILS CAN ABSORB SIGNIFICANT RAINFALL. THUS...SIGNIFICANT
RISES ON MAIN STEM RIVERS SUCH AS THE SOURIS AND JAMES ARE NOT
EXPECTED. HOWEVER...ENHANCED RAINFALL RATES OR SEVERAL ROUNDS OF
STORMS COULD PRODUCE LOCALIZED RUNOFF...LEADING TO RISES ON SMALL
CREEKS AND STREAMS...AND POSSIBLY FLASH FLOODING.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 637 AM CDT FRI MAY 17 2013

SHOWERS AND ISOLATED THUNDERSTORMS MOVING NORTHEAST ACROSS WESTERN
NORTH DAKOTA COULD APPROACH KMOT DURING THE FIRST FEW HOURS OF THE
TAF.  THE REMAINDER OF THE TAF SITES SHOULD STAY DRY THIS
MORNING...THOUGH THE CHANCES OF SHOWERS AND A FEW THUNDERSTORMS WILL
INCREASE LATE THIS AFTERNOON INTO TONIGHT.

CEILINGS IN PARTICULAR ARE A CHALLENGE RIGHT FROM THE BEGINNING WITH
PARTS OF CENTRAL AND WESTERN NORTH DAKOTA ALREADY SHOWING LOCATIONS
WITH MVFR / IFR CONDITIONS.  KMOT BRIEFLY FELL TO IFR...WHILE KISN
AND KDIK ARE CURRENTLY MVFR.  FORECAST SOUNDINGS SUGGEST CEILINGS
SHOULD IMPROVE LATER THIS MORNING BEFORE THEY DECLINE AGAIN TONIGHT
IN THE RAIN.  GENERALLY STAYED MVFR WITH CEILINGS / VISIBILITIES IN
THE RAIN...BUT COULD SEE THOSE BEING DROPPED LOWER ONCE MORE
CONFIDENCE IN THE TIMING CAN BE ESTABLISHED.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...SCHECK
SHORT TERM/AVIATION...CK
LONG TERM...RP KINNEY

000
FXUS63 KFGF 171452
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
952 AM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 952 AM CDT FRI MAY 17 2013

CONTINUED THE TREND OF LOWERING SHOWER CHANCES FOR TODAY. THERE IS
AN UPPER WAVE THAT WILL CLIP THE NW FA WITH SCATTERED SHOWERS INTO
THE EARLY AFTERNOON. OTHERWISE...THERE IS LITTLE SUPPORT FOR
PRECIP UNTIL LATER THIS EVENING WHEN STRONGER LOW LEVEL FLOW WILL
INCREASE MOISTURE AND CONVERGENCE. ALSO UPDATED THE SKY TO
INDICATE A PERIOD OF CLEARING ACROSS THE SOUTHERN FA. LOW LEVEL
FLOW WILL INCREASE FROM THE SOUTH TODAY...AND THERE IS A SHARP
GRADIENT FROM 30F DEWPOINTS TO 50F DEWPOINTS JUST SOUTH OF THE FA.
THIS HIGHER MOISTURE SHOULD BE ADVECTED INTO THE FA THROUGH THE
DAY AND INCREASE LOW CLOUDS FROM THE SOUTH. NO BIG CHANGES TO MAX
TEMPS...BUT WE MAY BE TOO LOW FOR SOME AREAS THAT SEE A LONGER
PERIOD OF SOLAR.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 325 AM CDT FRI MAY 17 2013

FORECAST CHALLENGE CONCERNS PCPN CHANCES/AMOUNTS AND TEMPERATURES.
MODELS IN GENERAL AGREEMENT WITH MAIN FEATURES HOWEVER ALL DIFFER
ON QPF SCENARIOS THROUGH THE SHORT TERM. AT THIS POINT WILL USE A
GENERAL BLEND.

PERSISTENT BAND OF -SHRA ASSOCIATED WITH ELEVATED ZONE OF
ENHANCED WARM ADVECTION AND H7 CONVERGENCE SHOULD GRADUALLY WEAKEN
THROUGH THE MORNING AS ABOVE FEATURES WEAKEN AND SHIFT NE. WILL GO
WITH HIGH POP/LOW QPF INTO MID MORNING THEN TRIM BACK ON POPS.
ELSEWHERE CONFIDENCE LOW ON ANY PCPN POTENTIAL THROUGH THE BULK OF
THE DAY. SURFACE LOW AND E-W ORIENTED WARM FRONTAL BOUNDARY ALONG
SD/NE BORDER INTO IA LIFTS SLOWLY THROUGH SD DURING THE DAY.
EXPECT MOST PCPN WILL BE ORIENTED CLOSER TO LOW LEVEL BOUNDARY TO
OUR SOUTH. WILL INCREASE POPS SOMEWHAT LATER IN THE AFTERNOON AS
BOUNDARY APPROACHES. TEMPERATURES WILL BE HIGHLY INFLUENCED BY
CLOUDS. RAISED TEMPERATURES SLIGHTLY ACROSS THE SOUTH WHERE SOME
THINNER CLOUD COVER EXISTS OTHERWISE WILL STICK WITH PERSISTENCE.

AS WARM FRONT LIFTS NORTH TONIGHT EXPECT RAIN CHANCES TO INCREASE
AND BY MID EVENING SOUTHERN AND WESTERN FORECAST AREAS LOOK TO BE
FAVORED AREAS FOR SHRA/TSRA. BEST THUNDER POTENTIAL WILL BE ACROSS
THE SOUTH AS NORTHERN AREAS STILL PRETTY STABLE. BAND OF PCPN
SHOULD LIFT NORTHWARD OVERNIGHT NIGHT AND ADJUSTED POPS
ACCORDINGLY.

FRONTAL BOUNDARY WILL BE ORIENTED ACROSS FA SATURDAY SO INCREASED
POPS. SEVERE POTENTIAL LOOKS BEST LATE IN THE AFTERNOON ACROSS THE
SOUTH HALF OF THE FA WITH FAVORABLE CONVECTIVE PARAMETERS.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI MAY 17 2013

SEVERE CONVECTIVE THREAT WILL CONTINUE INTO THE EVENING. WITH
PRECIPITABLE H2O VALUES AROUND 1.5 INCHES HEAVY RAIN WILL BE A
POSSIBILITY. INITIALLY FAVORED AREA FOR HEAVY RAIN LOOKS TO BE
ACROSS S HALF OF FA LIFTING NORTHWARD DURING THE OVERNIGHT.

WITH CUT OFF LOW DEVELOPING VCNTY OF FA POTENTIAL FOR SIGNIFICANT
RAIN WILL CONTINUE THROUGH THE WEEKEND AND WILL NEED TO MONITOR
RAIN AMOUNTS CLOSELY. AT THIS POINT LONG DURATION RAIN EVENT FOR
SURE BUT NOT ENOUGH CONFIDENCE ON ANY PARTICULAR LOCATION FOR
FLOOD/FLASH FLOOD WATCH.

0 UTC GFS/ECMWF/GEM IN GOOD OVERALL AGREEMENT NEXT WEEK...SHOWING A
CLOSED 500 HPA LOW ACROSS SOUTHEAST SD MONDAY MORNING CRAWLING
PAINFULLY SLOW TO THE EAST THROUGH WEDNESDAY. THIS FIRMLY ENTRENCHES
THE FORECAST AREA IN WRAP-AROUND RAIN SHOWERS THROUGH TUESDAY...
SLOWLY DRYING OUT WEDNESDAY AND A RETURN TO DRY CONDITIONS ON THURSDAY.
WILL KEEP THUNDER MENTION THROUGH MONDAY...BUT MOST INSTABILITY
SHOULD MOVE TO THE SOUTH BY TUESDAY. WITH CLOUD COVER AND RAIN...
TEMPERATURES WILL BE NEAR OR SLIGHTLY BELOW MID-MAY NORMALS WITH
HIGHS IN THE UPPER 50S AND 60S AND LOWS IN THE 40S/LOWER 50S. WITH
GREATER SUNSHINE AND DRY CONDITIONS...SHOULD SEE SOME AREAS REACHING
70 DEGREES BY THURSDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 640 AM CDT FRI MAY 17 2013

PRIMARILY LOOKING AT VFR CONDITIONS THROUGH THE DAY. A FEW SHOWERS
MAY CLIP THE DVL AREA THIS MORNING. OTHERWISE FEEL ANY SHRA/STORM
DEVELOPMENT WILL HOLD OFF TIL THIS EVENING. SOME MVFR/IFR CIGS
ACROSS WESTERN DAKOTAS BUT NOT ENOUGH CONFIDENCE AS TO HOW FAR
EAST LOWER CIGS WILL GET. THIS WILL NEED TO BE MONITORED.


&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...TG
SHORT TERM...VOELKER
LONG TERM...VOELKER/ROGERS
AVIATION...VOELKER

000
FXUS63 KFGF 171143
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
643 AM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 640 AM CDT FRI MAY 17 2013

DECREASED POPS ACROSS THE FAR NORTH AS A MAJORITY OF THE SHRA HAVE
LIFTED NE AS FORCING WEAKENED. STILL A SMALL CLUSTER OF SHRA OVER
CENTRAL ND WHICH MAY CLIP THE NORTH SO MAINTAIN HIGHER POPS THERE.
CLEARING SPREADING INTO SW FA. NOT SURE HOW FAR E CLEARING WILL
GET BUT DID DECREASE CLOUD COVER AS FAR EAST AS THE SOUTHERN
VALLEY. WITH CLEARING AND NOT MUCH HAPPENING UPSTREAM ALSO CUT
POPS IN THIS AREA THROUGH THE MORNING. DEGREE OF SOLAR WILL IMPACT
TEMPERATURES BUT AT THIS POINT WITH WARMEST MAXIMUM VALUES ACROSS
THE SOUTH IN LINE WITH LESS CLOUDS LEFT VALUES AS IS.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 325 AM CDT FRI MAY 17 2013

FORECAST CHALLENGE CONCERNS PCPN CHANCES/AMOUNTS AND TEMPERATURES.
MODELS IN GENERAL AGREEMENT WITH MAIN FEATURES HOWEVER ALL DIFFER
ON QPF SCENARIOS THROUGH THE SHORT TERM. AT THIS POINT WILL USE A
GENERAL BLEND.

PERSISTENT BAND OF -SHRA ASSOCIATED WITH ELEVATED ZONE OF
ENHANCED WARM ADVECTION AND H7 CONVERGENCE SHOULD GRADUALLY WEAKEN
THROUGH THE MORNING AS ABOVE FEATURES WEAKEN AND SHIFT NE. WILL GO
WITH HIGH POP/LOW QPF INTO MID MORNING THEN TRIM BACK ON POPS.
ELSEWHERE CONFIDENCE LOW ON ANY PCPN POTENTIAL THROUGH THE BULK OF
THE DAY. SURFACE LOW AND E-W ORIENTED WARM FRONTAL BOUNDARY ALONG
SD/NE BORDER INTO IA LIFTS SLOWLY THROUGH SD DURING THE DAY.
EXPECT MOST PCPN WILL BE ORIENTED CLOSER TO LOW LEVEL BOUNDARY TO
OUR SOUTH. WILL INCREASE POPS SOMEWHAT LATER IN THE AFTERNOON AS
BOUNDARY APPROACHES. TEMPERATURES WILL BE HIGHLY INFLUENCED BY
CLOUDS. RAISED TEMPERATURES SLIGHTLY ACROSS THE SOUTH WHERE SOME
THINNER CLOUD COVER EXISTS OTHERWISE WILL STICK WITH PERSISTENCE.

AS WARM FRONT LIFTS NORTH TONIGHT EXPECT RAIN CHANCES TO INCREASE
AND BY MID EVENING SOUTHERN AND WESTERN FORECAST AREAS LOOK TO BE
FAVORED AREAS FOR SHRA/TSRA. BEST THUNDER POTENTIAL WILL BE ACROSS
THE SOUTH AS NORTHERN AREAS STILL PRETTY STABLE. BAND OF PCPN
SHOULD LIFT NORTHWARD OVERNIGHT NIGHT AND ADJUSTED POPS
ACCORDINGLY.

FRONTAL BOUNDARY WILL BE ORIENTED ACROSS FA SATURDAY SO INCREASED
POPS. SEVERE POTENTIAL LOOKS BEST LATE IN THE AFTERNOON ACROSS THE
SOUTH HALF OF THE FA WITH FAVORABLE CONVECTIVE PARAMETERS.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI MAY 17 2013

SEVERE CONVECTIVE THREAT WILL CONTINUE INTO THE EVENING. WITH
PRECIPITABLE H2O VALUES AROUND 1.5 INCHES HEAVY RAIN WILL BE A
POSSIBILITY. INITIALLY FAVORED AREA FOR HEAVY RAIN LOOKS TO BE
ACROSS S HALF OF FA LIFTING NORTHWARD DURING THE OVERNIGHT.

WITH CUT OFF LOW DEVELOPING VCNTY OF FA POTENTIAL FOR SIGNIFICANT
RAIN WILL CONTINUE THROUGH THE WEEKEND AND WILL NEED TO MONITOR
RAIN AMOUNTS CLOSELY. AT THIS POINT LONG DURATION RAIN EVENT FOR
SURE BUT NOT ENOUGH CONFIDENCE ON ANY PARTICULAR LOCATION FOR
FLOOD/FLASH FLOOD WATCH.

0 UTC GFS/ECMWF/GEM IN GOOD OVERALL AGREEMENT NEXT WEEK...SHOWING A
CLOSED 500 HPA LOW ACROSS SOUTHEAST SD MONDAY MORNING CRAWLING
PAINFULLY SLOW TO THE EAST THROUGH WEDNESDAY. THIS FIRMLY ENTRENCHES
THE FORECAST AREA IN WRAP-AROUND RAIN SHOWERS THROUGH TUESDAY...
SLOWLY DRYING OUT WEDNESDAY AND A RETURN TO DRY CONDITIONS ON THURSDAY.
WILL KEEP THUNDER MENTION THROUGH MONDAY...BUT MOST INSTABILITY
SHOULD MOVE TO THE SOUTH BY TUESDAY. WITH CLOUD COVER AND RAIN...
TEMPERATURES WILL BE NEAR OR SLIGHTLY BELOW MID-MAY NORMALS WITH
HIGHS IN THE UPPER 50S AND 60S AND LOWS IN THE 40S/LOWER 50S. WITH
GREATER SUNSHINE AND DRY CONDITIONS...SHOULD SEE SOME AREAS REACHING
70 DEGREES BY THURSDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 640 AM CDT FRI MAY 17 2013

PRIMARILY LOOKING AT VFR CONDITIONS THROUGH THE DAY. A FEW SHOWERS
MAY CLIP THE DVL AREA THIS MORNING. OTHERWISE FEEL ANY SHRA/STORM
DEVELOPMENT WILL HOLD OFF TIL THIS EVENING. SOME MVFR/IFR CIGS
ACROSS WESTERN DAKOTAS BUT NOT ENOUGH CONFIDENCE AS TO HOW FAR
EAST LOWER CIGS WILL GET. THIS WILL NEED TO BE MONITORED.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...VOELKER
SHORT TERM...VOELKER
LONG TERM...VOELKER/ROGERS
AVIATION...VOELKER

000
FXUS63 KBIS 171138
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
638 AM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 637 AM CDT FRI MAY 17 2013

UPDATE FOR MINOR CHANGES TO POPS ACROSS THE NORTH THIS MORNING AS
BATCH OF SHOWERS AND ISOLATED THUNDERSTORMS CONTINUES TO HEAD
NORTHEAST. OTHERWISE...MAINTAINED GENERALLY INCREASING POPS
THROUGH LATE AFTERNOON AND EVENING.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM CDT FRI MAY 17 2013

THE MAIN CONCERN FOR TODAY INTO TONIGHT WILL BE THE CHANCE OF
THUNDERSTORMS AND POTENTIAL SEVERE WEATHER. EARLY MORNING RADAR
MOSAIC SHOWED ISOLATED SHOWERS FROM SOUTHWEST NORTH DAKOTA INTO
NORTHWEST MINNESOTA. MUCH OF THIS ACTIVITY DEVELOPED IN AN AREA OF
H85 WARM AIR ADVECTION THAT HAS BEEN MOVING FROM SOUTH TO NORTH
ACROSS THE REGION. THE STRONGEST WARM AIR ADVECTION SHIFTS NORTH BY
AFTERNOON AS SOUTHWESTERLY FLOW ALOFT BRINGS A SERIES OF WAVES ACROSS
THE STATE. WILL MAINTAIN FAIRLY HIGH POPS TODAY...ESPECIALLY IN
THE NORTH AND WEST WHERE THE MAJORITY OF MODEL SOLUTIONS FAVOR THE
HIGHER PRECIPITATION CHANCES.

THE FOCUS THEN TURNS FARTHER SOUTH AS SURFACE LOW PRESSURE GATHERS
IN EAST CENTRAL WYOMING. A WARM FRONT STRETCHING OUT OF THE LOW
INTO SOUTHERN SOUTH DAKOTA IS EXPECTED TO LIFT NORTH TONIGHT...BRINGING
INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS TO CENTRAL AND
WESTERN NORTH DAKOTA. CAN NOT RULE OUT AN ISOLATED SEVERE STORM
LATE THIS AFTERNOON / EVENING ACROSS THE SOUTHERN PART OF THE
FORECAST AREA WHERE INSTABILITY WILL BE GREATEST. THE SPC DAY 1
SEVERE WEATHER OUTLOOK KEEPS THE SLIGHT RISK SOUTH OF THE FORECAST
AREA...HOWEVER THE 5 PERCENT PROBABILITIES FOR SEVERE HAIL / WIND
ARE DRAWN SOUTH OF I-94 INTO SOUTHERN NORTH DAKOTA WHICH APPEARS
REASONABLE.

TEMPERATURES TODAY WILL BE TRICKY DUE TO THE CLOUDS AND RAIN. WILL
GENERALLY STAY ON THE COOL SIDE OF GUIDANCE WHICH SUGGESTS MID
60S NORTH TO LOWER 70S SOUTH.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 349 AM CDT FRI MAY 17 2013

THE MAIN FORECAST ISSUES THROUGH THE LONG TERM PERIOD ARE CONVECTIVE
TRENDS...AND POTENTIAL FOR PROLONGED MODERATE TO HEAVY RAIN AND
SOME SEVERE WEATHER ON SATURDAY. THE LATEST 17/00Z MODEL RUNS HAVE
SOME SIGNIFICANT DIFFERENCE IN THE PROGRESSION OF A CLOSED UPPER
LOW THROUGH THE REGION THROUGH EARLY NEXT WEEK. THE NAM IS AMONG
THE FARTHEST WEST...WHILE THE GFS FAVORS A FASTER...MORE EASTERLY
PATH. THE ECMWF REPRESENTS A REASONABLE COMPROMISE...AND WOULD
KEEP SHOWERS AROUND INTO TUESDAY BEFORE PUSHING EAST. THE FAVORED
PERIOD FOR SEVERE WEATHER WILL BE SATURDAY...WITH SOUTHWEST FLOW
ALOFT AND A WARM FRONT NOSING INTO THE SOUTHEAST PORTION OF THE
FORECAST AREA. SPC CONTINUES TO HAVE THE SOUTHEAST OUTLOOKED IN
SLIGHT RISK FOR DAY 2. BUFR SOUNDINGS SUGGEST STORMS WILL DEVELOP
RELATIVELY EARLY IN THE DAY. AM EXPECTING SOME STRONG TO SEVERE
STORMS WITH LARGE HAIL/STRONG WIND GUSTS THE PRIMARY THREATS.
STRONG MOISTURE TRANSPORT INTO THE BOUNDARY WILL CONTINUE THROUGH
SATURDAY NIGHT AS A DECENT SHORT WAVE TROUGH MOVES THROUGH EASTERN
NORTH DAKOTA. THE SEVERE WEATHER THREAT DIMINISHES SUNDAY...BUT
MODERATE TO LOCALLY HEAVY RAIN IS EXPECTED TO CONTINUE OVER MUCH
OF WESTERN AND CENTRAL NORTH DAKOTA. THIS SCENARIO WILL LIKELY
CONTINUE MONDAY...BEFORE SHOWERS TAPER OFF IN COVERAGE AND
INTENSITY ON TUESDAY. TOTAL RAINFALL AMOUNTS OF 1 TO 3 ARE
EXPECTED THROUGH THE PERIOD...WITH AMOUNTS AROUND 4 INCHES
POSSIBLE...ESPECIALLY IN THE JAMES RIVER VALLEY. CONDITIONS ARE
SUCH THAT SOILS CAN ABSORB SIGNIFICANT RAINFALL. THUS...SIGNIFICANT
RISES ON MAIN STEM RIVERS SUCH AS THE SOURIS AND JAMES ARE NOT
EXPECTED. HOWEVER...ENHANCED RAINFALL RATES OR SEVERAL ROUNDS OF
STORMS COULD PRODUCE LOCALIZED RUNOFF...LEADING TO RISES ON SMALL
CREEKS AND STREAMS...AND POSSIBLY FLASH FLOODING.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 637 AM CDT FRI MAY 17 2013

SHOWERS AND ISOLATED THUNDERSTORMS MOVING NORTHEAST ACROSS WESTERN
NORTH DAKOTA COULD APPROACH KMOT DURING THE FIRST FEW HOURS OF THE
TAF.  THE REMAINDER OF THE TAF SITES SHOULD STAY DRY THIS
MORNING...THOUGH THE CHANCES OF SHOWERS AND A FEW THUNDERSTORMS WILL
INCREASE LATE THIS AFTERNOON INTO TONIGHT.

CEILINGS IN PARTICULAR ARE A CHALLENGE RIGHT FROM THE BEGINNING WITH
PARTS OF CENTRAL AND WESTERN NORTH DAKOTA ALREADY SHOWING LOCATIONS
WITH MVFR / IFR CONDITIONS.  KMOT BRIEFLY FELL TO IFR...WHILE KISN
AND KDIK ARE CURRENTLY MVFR.  FORECAST SOUNDINGS SUGGEST CEILINGS
SHOULD IMPROVE LATER THIS MORNING BEFORE THEY DECLINE AGAIN TONIGHT
IN THE RAIN.  GENERALLY STAYED MVFR WITH CEILINGS / VISIBILITIES IN
THE RAIN...BUT COULD SEE THOSE BEING DROPPED LOWER ONCE MORE
CONFIDENCE IN THE TIMING CAN BE ESTABLISHED.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE/LONG TERM...RP KINNEY
SHORT TERM/AVIATION...CK

000
FXUS63 KBIS 170850
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
350 AM CDT FRI MAY 17 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM CDT FRI MAY 17 2013

THE MAIN CONCERN FOR TODAY INTO TONIGHT WILL BE THE CHANCE OF
THUNDERSTORMS AND POTENTIAL SEVERE WEATHER. EARLY MORNING RADAR
MOSAIC SHOWED ISOLATED SHOWERS FROM SOUTHWEST NORTH DAKOTA INTO
NORTHWEST MINNESOTA. MUCH OF THIS ACTIVITY DEVELOPED IN AN AREA OF
H85 WARM AIR ADVECTION THAT HAS BEEN MOVING FROM SOUTH TO NORTH
ACROSS THE REGION. THE STRONGEST WARM AIR ADVECTION SHIFTS NORTH BY
AFTERNOON AS SOUTHWESTERLY FLOW ALOFT BRINGS A SERIES OF WAVES ACROSS
THE STATE. WILL MAINTAIN FAIRLY HIGH POPS TODAY...ESPECIALLY IN
THE NORTH AND WEST WHERE THE MAJORITY OF MODEL SOLUTIONS FAVOR THE
HIGHER PRECIPITATION CHANCES.

THE FOCUS THEN TURNS FARTHER SOUTH AS SURFACE LOW PRESSURE GATHERS
IN EAST CENTRAL WYOMING. A WARM FRONT STRETCHING OUT OF THE LOW
INTO SOUTHERN SOUTH DAKOTA IS EXPECTED TO LIFT NORTH TONIGHT...BRINGING
INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS TO CENTRAL AND
WESTERN NORTH DAKOTA. CAN NOT RULE OUT AN ISOLATED SEVERE STORM
LATE THIS AFTERNOON / EVENING ACROSS THE SOUTHERN PART OF THE
FORECAST AREA WHERE INSTABILITY WILL BE GREATEST. THE SPC DAY 1
SEVERE WEATHER OUTLOOK KEEPS THE SLIGHT RISK SOUTH OF THE FORECAST
AREA...HOWEVER THE 5 PERCENT PROBABILITIES FOR SEVERE HAIL / WIND
ARE DRAWN SOUTH OF I-94 INTO SOUTHERN NORTH DAKOTA WHICH APPEARS
REASONABLE.

TEMPERATURES TODAY WILL BE TRICKY DUE TO THE CLOUDS AND RAIN. WILL
GENERALLY STAY ON THE COOL SIDE OF GUIDANCE WHICH SUGGESTS MID
60S NORTH TO LOWER 70S SOUTH.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 349 AM CDT FRI MAY 17 2013

THE MAIN FORECAST ISSUES THROUGH THE LONG TERM PERIOD ARE CONVECTIVE
TRENDS...AND POTENTIAL FOR PROLONGED MODERATE TO HEAVY RAIN AND
SOME SEVERE WEATHER ON SATURDAY. THE LATEST 17/00Z MODEL RUNS HAVE
SOME SIGNIFICANT DIFFERENCE IN THE PROGRESSION OF A CLOSED UPPER
LOW THROUGH THE REGION THROUGH EARLY NEXT WEEK. THE NAM IS AMONG
THE FARTHEST WEST...WHILE THE GFS FAVORS A FASTER...MORE EASTERLY
PATH. THE ECMWF REPRESENTS A REASONABLE COMPROMISE...AND WOULD
KEEP SHOWERS AROUND INTO TUESDAY BEFORE PUSHING EAST. THE FAVORED
PERIOD FOR SEVERE WEATHER WILL BE SATURDAY...WITH SOUTHWEST FLOW
ALOFT AND A WARM FRONT NOSING INTO THE SOUTHEAST PORTION OF THE
FORECAST AREA. SPC CONTINUES TO HAVE THE SOUTHEAST OUTLOOKED IN
SLIGHT RISK FOR DAY 2. BUFR SOUNDINGS SUGGEST STORMS WILL DEVELOP
RELATIVELY EARLY IN THE DAY. AM EXPECTING SOME STRONG TO SEVERE
STORMS WITH LARGE HAIL/STRONG WIND GUSTS THE PRIMARY THREATS.
STRONG MOISTURE TRANSPORT INTO THE BOUNDARY WILL CONTINUE THROUGH
SATURDAY NIGHT AS A DECENT SHORT WAVE TROUGH MOVES THROUGH EASTERN
NORTH DAKOTA. THE SEVERE WEATHER THREAT DIMINISHES SUNDAY...BUT
MODERATE TO LOCALLY HEAVY RAIN IS EXPECTED TO CONTINUE OVER MUCH
OF WESTERN AND CENTRAL NORTH DAKOTA. THIS SCENARIO WILL LIKELY
CONTINUE MONDAY...BEFORE SHOWERS TAPER OFF IN COVERAGE AND
INTENSITY ON TUESDAY. TOTAL RAINFALL AMOUNTS OF 1 TO 3 ARE
EXPECTED THROUGH THE PERIOD...WITH AMOUNTS AROUND 4 INCHES
POSSIBLE...ESPECIALLY IN THE JAMES RIVER VALLEY. CONDITIONS ARE
SUCH THAT SOILS CAN ABSORB SIGNIFICANT RAINFALL. THUS...SIGNIFICANT
RISES ON MAIN STEM RIVERS SUCH AS THE SOURIS AND JAMES ARE NOT
EXPECTED. HOWEVER...ENHANCED RAINFALL RATES OR SEVERAL ROUNDS OF
STORMS COULD PRODUCE LOCALIZED RUNOFF...LEADING TO RISES ON SMALL
CREEKS AND STREAMS...AND POSSIBLY FLASH FLOODING.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1244 AM CDT FRI MAY 17 2013

MVFR / IFR CEILINGS CONTINUE TO SPREAD INTO PARTS OF CENTRAL AND
WESTERN NORTH DAKOTA EARLY THIS MORNING. THE WESTERN PART OF THE
STATE APPEARS FAVORED FOR THE LOWEST CEILINGS WITH THE 17.00Z NAM
SHOWING THE BEST LOW LEVEL SATURATION IN THAT REGION.

RAIN CHANCES REMAIN DIFFICULT TO PINPOINT WITH ENOUGH SPREAD IN
MODEL SOLUTIONS TO KEEP CONFIDENCE FAIRLY LOW IN SPECIFIC TIMING.
THE 17.03Z RAP STILL FAVORS THE NORTH THIS MORNING IN AN AREA OF
H85 WARM AIR ADVECTION. THIS IS GENERALLY IN LINE WITH CURRENT
RADAR TRENDS...SO WILL CONFINE ANY SHOWERS THIS MORNING TO KMOT
AND KISN.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM/AVIATION...CK
LONG TERM...RP KINNEY

000
FXUS63 KFGF 170830
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
330 AM CDT FRI MAY 17 2013

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 325 AM CDT FRI MAY 17 2013

FORECAST CHALLENGE CONCERNS PCPN CHANCES/AMOUNTS AND TEMPERATURES.
MODELS IN GENERAL AGREEMENT WITH MAIN FEATURES HOWEVER ALL DIFFER
ON QPF SCENARIOS THROUGH THE SHORT TERM. AT THIS POINT WILL USE A
GENERAL BLEND.

PERSISTENT BAND OF -SHRA ASSOCIATED WITH ELEVATED ZONE OF
ENHANCED WARM ADVECTION AND H7 CONVERGENCE SHOULD GRADUALLY WEAKEN
THROUGH THE MORNING AS ABOVE FEATURES WEAKEN AND SHIFT NE. WILL GO
WITH HIGH POP/LOW QPF INTO MID MORNING THEN TRIM BACK ON POPS.
ELSEWHERE CONFIDENCE LOW ON ANY PCPN POTENTIAL THROUGH THE BULK OF
THE DAY. SURFACE LOW AND E-W ORIENTED WARM FRONTAL BOUNDARY ALONG
SD/NE BORDER INTO IA LIFTS SLOWLY THROUGH SD DURING THE DAY.
EXPECT MOST PCPN WILL BE ORIENTED CLOSER TO LOW LEVEL BOUNDARY TO
OUR SOUTH. WILL INCREASE POPS SOMEWHAT LATER IN THE AFTERNOON AS
BOUNDARY APPROACHES. TEMPERATURES WILL BE HIGHLY INFLUENCED BY
CLOUDS. RAISED TEMPERATURES SLIGHTLY ACROSS THE SOUTH WHERE SOME
THINNER CLOUD COVER EXISTS OTHERWISE WILL STICK WITH PERSISTENCE.

AS WARM FRONT LIFTS NORTH TONIGHT EXPECT RAIN CHANCES TO INCREASE
AND BY MID EVENING SOUTHERN AND WESTERN FORECAST AREAS LOOK TO BE
FAVORED AREAS FOR SHRA/TSRA. BEST THUNDER POTENTIAL WILL BE ACROSS
THE SOUTH AS NORTHERN AREAS STILL PRETTY STABLE. BAND OF PCPN
SHOULD LIFT NORTHWARD OVERNIGHT NIGHT AND ADJUSTED POPS
ACCORDINGLY.

FRONTAL BOUNDARY WILL BE ORIENTED ACROSS FA SATURDAY SO INCREASED
POPS. SEVERE POTENTIAL LOOKS BEST LATE IN THE AFTERNOON ACROSS THE
SOUTH HALF OF THE FA WITH FAVORABLE CONVECTIVE PARAMETERS.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI MAY 17 2013

SEVERE CONVECTIVE THREAT WILL CONTINUE INTO THE EVENING. WITH
PRECIPITABLE H2O VALUES AROUND 1.5 INCHES HEAVY RAIN WILL BE A
POSSIBILITY. INITIALLY FAVORED AREA FOR HEAVY RAIN LOOKS TO BE
ACROSS S HALF OF FA LIFTING NORTHWARD DURING THE OVERNIGHT.

WITH CUT OFF LOW DEVELOPING VCNTY OF FA POTENTIAL FOR SIGNIFICANT
RAIN WILL CONTINUE THROUGH THE WEEKEND AND WILL NEED TO MONITOR
RAIN AMOUNTS CLOSELY. AT THIS POINT LONG DURATION RAIN EVENT FOR
SURE BUT NOT ENOUGH CONFIDENCE ON ANY PARTICULAR LOCATION FOR
FLOOD/FLASH FLOOD WATCH.

0 UTC GFS/ECMWF/GEM IN GOOD OVERALL AGREEMENT NEXT WEEK...SHOWING A
CLOSED 500 HPA LOW ACROSS SOUTHEAST SD MONDAY MORNING CRAWLING
PAINFULLY SLOW TO THE EAST THROUGH WEDNESDAY. THIS FIRMLY ENTRENCHES
THE FORECAST AREA IN WRAP-AROUND RAIN SHOWERS THROUGH TUESDAY...
SLOWLY DRYING OUT WEDNESDAY AND A RETURN TO DRY CONDITIONS ON THURSDAY.
WILL KEEP THUNDER MENTION THROUGH MONDAY...BUT MOST INSTABILITY
SHOULD MOVE TO THE SOUTH BY TUESDAY. WITH CLOUD COVER AND RAIN...
TEMPERATURES WILL BE NEAR OR SLIGHTLY BELOW MID-MAY NORMALS WITH
HIGHS IN THE UPPER 50S AND 60S AND LOWS IN THE 40S/LOWER 50S. WITH
GREATER SUNSHINE AND DRY CONDITIONS...SHOULD SEE SOME AREAS REACHING
70 DEGREES BY THURSDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1150 PM CDT THU MAY 16 2013

VFR CONDITIONS AND SLOWLY DIMINISHING LIGHT RA OVER
KDVL...KGFK...AND KTVF WILL CONTINUE FOR THE REST OF THE NIGHT.
SOME MVFR CONDITIONS WILL BE POSSIBLE AT KDVL AND POSSIBLY FURTHER
EAST.  WINDS WILL STAY EAST AROUND 10 KTS.


&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

SHORT TERM...VOELKER
LONG TERM...VOELKER/ROGERS
AVIATION...JR

000
FXUS63 KBIS 170546
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
1246 AM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 1244 AM CDT FRI MAY 17 2013

REGIONAL RADAR MOSAIC SHOWS ISOLATED TO SCATTERED SHOWERS ACROSS
NORTH CENTRAL AND NORTHEAST NORTH DAKOTA. THIS APPEARS TO LINE UP
WITH AN AREA OF H85 WARM AIR ADVECTION SHOWN BY THE 17.03Z RAP.
THE STRONGEST WARM AIR ADVECTION IS FORECAST TO BE ACROSS NORTHERN
PARTS OF THE STATE EARLY THIS MORNING...SO WILL HAVE THE HIGHEST
POPS IN THAT REGION. INSTABILITY REMAINS LIMITED THIS
MORNING...SO ANY THUNDER CHANCES SHOULD BE ISOLATED AT BEST.

UPDATE ISSUED AT 1016 PM CDT THU MAY 16 2013

ADJUSTED EVENING POPS DOWNWARD BASED ON CURRENT RADAR OBS/TRENDS.
OTHERWISE...NOT TOO MANY CHANGES WERE MADE TO THE ONGOING
FORECAST. THE UPDATED GRIDDED AND TEXT PRODUCTS HAVE BEEN SENT.

UPDATE ISSUED AT 718 PM CDT THU MAY 16 2013

REGIONAL RADAR TRENDS INDICATE NUMEROUS SHOWERS ACROSS THE JAMES
RIVER BASIN CONTINUING TO PUSH EAST OF THE CWA THIS EVENING. WITH
THE ATMOSPHERE PRETTY WELL WORKED OVER...DECREASED POPS WEST AND
CENTRAL THROUGH THE REMAINDER OF THE EVENING HOURS.

HOWEVER...SHORT RANGE MODEL GUIDANCE CONTINUES TO PROG INCREASING PRECIP
CHANCES AFTER MIDNIGHT AS AN UPPER WAVE APPROACHES FROM THE
SOUTHWEST. SHOWALTER INDICES INDICATE THUNDER POTENTIAL DEVELOPING
ACROSS SOUTHWESTERN NORTH DAKOTA AFTER MIDNIGHT. AS A
RESULT...REMOVED THUNDER AREAWIDE TONIGHT AND ONLY INDICATED
ISOLATED THUNDER SOUTHWEST DEVELOPING AFTER MIDNIGHT.

UPDATED THE HOURLY SENSIBLE WEATHER GRIDS BASED ON CURRENT
OBS/TRENDS. THE UPDATED GRIDDED AND TEXT PRODUCTS HAVE BEEN SENT.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 300 PM CDT THU MAY 16 2013

LATEST WATER VAPOR IMAGERY SHOWS A SOUTHWEST FLOW INTO NORTH DAKOTA
AHEAD OF AN UPPER TROUGH WHICH IS SLIDING INTO THE NORTHWEST COAST.
FOR THE NEAR TERM...THROUGH THURSDAY EVENING...CATEGORICAL POPS
WILL CONTINUE FROM BLAT TO MCCLUSKY INTO BISMARCK AND AREAS TO
THE EAST AS A SHORTWAVE PROPAGATES THROUGH. THERE IS A BREAK IN
THE CLOUDS AND PRECIPITATION IN THE FAR WEST WITH MORE SHORTWAVES
MOVING INTO CENTRAL MONTANA. THESE WILL MOVE THROUGH TONIGHT INTO
FRIDAY GENERATING ISOLATED TO SCATTERED SHOWERS. BEST CHANCE FOR
AN ISOLATED THUNDERSTORM WILL RESIDE IN THE WEST AND SOUTH INTO
TONIGHT. LATEST VISIBLE IMAGERY SHOWS SOME CLEARING IN THE WEST
WITH CLOUDS BEGINNING TO BILLOW UP IN NORTHEAST MONTANA. FOR
FRIDAY...SOME INSTABILITY CONTINUES IN THE SOUTHWEST AND FAR SOUTH
CENTRAL FOR A MENTION OF THUNDERSTORMS...OTHERWISE SCATTERED
SHOWERS WILL GENERALLY BE THE RULE.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 PM CDT THU MAY 16 2013

A BROADENING UPPER LEVEL LOW POSITIONED OVER THE WESTERN CONUS EARLY
THE EXTENDED WILL ALLOW FOR MOIST SOUTHWESTERLY FLOW TO CONTINUE
ACROSS THE NORTHERN PLAINS SATURDAY INTO SUNDAY. AS THIS BROAD UPPER
LEVEL TROUGH SLOWLY SHIFTS EAST AND OVER THE REGION LATE SUNDAY AND
EARLY MONDAY THE FLOW WILL BECOME SOUTHERLY AS THE UPPER LEVEL
TROUGH CLOSES OFF OVER THE DAKOTAS. IT WILL REMAIN OVERHEAD MONDAY
AND TUESDAY BEFORE MOVING EAST THEREAFTER. 12Z GFS/GEM/NAM/ECWMF ARE
IN GOOD AGREEMENT REGARDING THIS PATTERN...BEFORE SOLUTIONS DIVERGE
LATE IN THE EXTENDED AS THE UPPER LEVEL LOW MOVES EAST.

THE MAIN ISSUE FOR THE EXTENDED WILL BE THE POTENTIAL FOR HEAVY RAIN
THROUGH EARLY NEXT WEEK. THERE IS DECENT AGREEMENT BETWEEN THE 12Z
MODEL RUNS REGARDING THE PLACEMENT AND AMOUNT OF PRECIPITATION
ACROSS THE AREA...WITH THE HEAVIEST AMOUNTS FOCUSED ON THE JAMES
RIVER VALLEY AND POINTS EAST. A SECOND AREA OF HEAVY PRECIPITATION
MAY BE POSSIBLE ACROSS THE NORTHWEST. HOWEVER...THERE IS A BIT
MORE UNCERTAINTY FOR THE NORTHWEST AREA. IN ADDITION...THE 12Z
GFS AND NAM CONTINUE TO PLACE PRECIPITABLE WATER VALUES OF 1.30 TO
1.50 INCHES ACROSS THE EASTERN TWO THIRDS OF NORTH DAKOTA SATURDAY
THROUGH EARLY SUNDAY MORNING. ACCORDING TO PW CLIMATOLOGY...THESE
FORECAST VALUES WILL BE IN THE 99TH PERCENTILE TO THE HIGHEST EVER
OBSERVED FOR THE MONTH OF MAY. CONFIDENCE IS INCREASING FOR 1 TO 2
INCHES (WITH LOCALLY HIGHER AMOUNTS ACROSS THE JAMES RIVER VALLEY)
OF RAINFALL THROUGH SUNDAY EVENING. ADDITIONAL LIGHT TO MODERATE
RAIN WILL CONTINUE THROUGH TUESDAY AS THE UPPER LEVEL LOW IS
OVERHEAD...BRINGING POTENTIAL RAINFALL TOTALS THROUGH TUESDAY INTO
THE 2 TO 4 INCH RANGE. THIS WILL HAVE TO BE MONITORED CLOSELY OVER
THE NEXT FEW DAYS AS POTENTIAL HYDRO ISSUES FOR THE JAMES RIVER
MAY COME INTO PLAY. ALSO...THIS HEAVY RAIN EVENT WILL POTENTIALLY
ALLEVIATE THE RAINFALL DEFICITS OBSERVED SO FAR FOR MAY.

REGARDING THE POTENTIAL FOR SEVERE WEATHER...THE BEST CHANCES FOR
ANY SEVERE WEATHER WILL COME SATURDAY AFTERNOON THROUGH EARLY SUNDAY
MORNING FOR LOCATIONS EAST OF STATE HIGHWAY 83 AND SOUTH OF
INTERSTATE 94. ISOLATED SEVERE MAY BE POSSIBLE FOR THE SOUTHWEST
LATE SATURDAY AFTERNOON AND EARLY EVENING. SUFFICIENT MOISTURE
WILL BE PRESENT DUE TO PREVIOUS MOISTURE RECEIVED ON THURSDAY AND
FRIDAY. BULK SHEAR VALUES WILL BE IN THE 40 TO 50 KT RANGE DURING
THIS PERIOD...WITH ML CAPE IN THE 1000 TO 2000 J/KG RANGE FOR THE
FAR SOUTH CENTRAL...AND 2000 TO 3000 J/LG VALUES ACROSS THE
SOUTHERN JAMES RIVER VALLEY. MU CAPE VALUES WILL BE IN THE 1200 TO
3000 J/KG RANGE AS WELL. HOWEVER...THE MAIN LIMITING FACTOR WILL
BE THE WARM AIR ALOFT...AS THE NAM/GFS BUFR SOUNDINGS FOR JMS/BIS
DEPICT A DECENT CAP INVERSION. THIS MAY BE OVERCOME BY DAYTIME
HEATING AND LARGE SCALE ASCENT ASSOCIATED WITH THE AFOREMENTIONED
UPPER LEVEL TROUGH.

BEYOND TUESDAY...THE UPPER LEVEL LOW WILL MOVE EAST AND IN ITS
WAKE...UPPER LEVEL RIDING WILL COMMENCE. A PERIOD OF DRIER AND
SEASONABLE TEMPERATURES ARE FORECAST FOR WEDNESDAY AND THURSDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1244 AM CDT FRI MAY 17 2013

MVFR / IFR CEILINGS CONTINUE TO SPREAD INTO PARTS OF CENTRAL AND
WESTERN NORTH DAKOTA EARLY THIS MORNING. THE WESTERN PART OF THE
STATE APPEARS FAVORED FOR THE LOWEST CEILINGS WITH THE 17.00Z NAM
SHOWING THE BEST LOW LEVEL SATURATION IN THAT REGION.

RAIN CHANCES REMAIN DIFFICULT TO PINPOINT WITH ENOUGH SPREAD IN
MODEL SOLUTIONS TO KEEP CONFIDENCE FAIRLY LOW IN SPECIFIC TIMING.
THE 17.03Z RAP STILL FAVORS THE NORTH THIS MORNING IN AN AREA OF
H85 WARM AIR ADVECTION. THIS IS GENERALLY IN LINE WITH CURRENT
RADAR TRENDS...SO WILL CONFINE ANY SHOWERS THIS MORNING TO KMOT
AND KISN.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...CK
SHORT TERM...KS
LONG TERM...LTH
AVIATION...CK

000
FXUS63 KFGF 170450
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
1150 PM CDT THU MAY 16 2013

.UPDATE...
ISSUED AT 1150 PM CDT THU MAY 16 2013

BAND OF PRECIP ALONG HIGHWAY 2 HAS BEGUN TO DIMINISH AS 700MB
FRONTOGENESIS HAS DECREASED. TRENDED DOWNWARD SLOWLY WITH POPS
OVER THAT AREA FOR THE REST OF THE NIGHT. PRECIP TO OUR SOUTH HAS
STAYED WELL CLEAR OF OUR SOUTHEASTERN BORDERS...SO LOWERED POPS
UNTIL LATER IN THE DAY TOMORROW. MADE A FEW MINOR TWEAKS TO TEMPS
AND WINDS.

UPDATE ISSUED AT 937 PM CDT THU MAY 16 2013

SFC HIGH PRESSURE OVER ONTARIO AND A DEVELOPING LOW OVER CO/WY
CONTINUES TO BRING NORTHEASTERLY WINDS THAT WILL SLOWLY SHIFT
AROUND TO THE EAST LATER TONIGHT. STILL THINK THAT OUR LIGHT RAIN
ALONG THE HIGHWAY 2 CORRIDOR WILL SLOWLY DIMINISH AS CONVECTION
RAMPS UP FURTHER SOUTH. HOWEVER...PRECIP HAS MOVED A BIT FURTHER
EAST THAN EARLIER EXPECTATIONS SO ADJUSTED POPS/WX ACCORDINGLY.
KEPT LIKELIES GOING FOR THE REST OF THE EVENING AND THEN STARTED
TO DROP THEM DOWN LATER TONIGHT.

UPDATE ISSUED AT 646 PM CDT THU MAY 16 2013

BAND OF LIGHT RAIN CONTINUES FROM NEAR DEVILS LAKE TO THE CENTRAL
RED RIVER VALLEY INTO NORTHWESTERN MINNESOTA...WITH SPRINKLES
ELSEWHERE. THE NAM AND RAP ARE IN PRETTY GOOD AGREEMENT ON THIS
ACTIVITY DIMINISHING LATER THIS EVENING AS THE COMPLEX OVER SD/MN
GETS GOING AND ROBS MOISTURE. KEPT HIGH POPS IN THE NORTH THIS
EVENING BEFORE TRANSITIONING TO BETTER PERCENTAGES IN THE SOUTH
LATER ON TONIGHT. LOWERED TEMPS A BIT IN THE NORTHWEST AS READINGS
HAVE ALREADY DROPPED INTO THE LOWER 50S AND THERE COULD BE SOME
BREAKS IN THE CLOUDS LATER TONIGHT TO ALLOW IT TO GET DOWN INTO
THE UPPER 40S.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 120 PM CDT THU MAY 16 2013

THE MAIN CHALLENGE WILL BE UPCOMING PROLONGED WET PATTERN TONIGHT
INTO THE MIDDLE OF NEXT WEEK. MODELS ARE IN GOOD OVERALL AGREEMENT
INITIALLY...WITH SOME DIFFERENCES BY NEXT WEEK. THE NAM/GFS ARE A
GOOD COMPROMISE IN THE NEAR TERM.

FOR TONIGHT...THERE WILL BE AN AREA OF SHOWERS MOVING FROM WEST TO
EAST ACROSS THE AREA. THIS BAND OF SHOWERS IS BEING AIDED BY
STRONG MID LEVEL OMEGA AND UPPER LEVEL DIVERGENCE...AS PWATS
INCREASE TO AROUND 1 INCH. THERE SHOULD BE A BAND OF STRONGER
CONVECTION SOUTH OF THE AREA OVERNIGHT...THAT SHOULD ROB THE
DEEPER MOISTURE FROM OUR AREA. WE WILL INCREASE POPS THIS EVENING
IN THE WEST INTO THE CENTRAL RED RIVER VALLEY WITH STRONGER ECHOES
MOVING INTO THE AREA.

FOR FRIDAY...WE SHOULD GET A BREAK IN THE LARGER SCALE SHOWERS
WITH EASTERLY FLOW NEAR THE SFC INCREASING. WE WILL MAINTAIN A LOW
CHANCE FOR SHOWERS THOUGH WITH PLENTY OF CLOUDS AND POSSIBLY A
SUBTLE SHORTWAVE MOVING THROUGH.

FOR FRIDAY NIGHT...A LLJ WILL DEVELOP IN SD AND MOVE INTO THE
SOUTH OVERNIGHT EXPECT AN AREA OF SHOWERS AND THUNDERSTORMS TO
MOVE INTO THE AREA...WITH THE BEST CHANCE FOR THUNDER IN THE
SOUTH. THERE WILL BE SOME ELEVATED INSTABILITY WITH 850MB CAPE
AROUND 1000 J/KG...SO A STRONG TO LOCALLY SEVERE STORM IS POSSIBLE.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 310 PM CDT THU MAY 16 2013

FOR SATURDAY THROUGH SUNDAY...A VERY ACTIVE WEATHER PATTERN IS
EXPECTED. SHOWERS AND STORMS SHOULD BE ONGOING AT LEAST IN THE
SOUTH SATURDAY MORNING. BY SATURDAY AFTERNOON AND EVENING...DEEP
MOISTURE AND STRONG INSTABILITY SHOULD DEVELOP OVER SE ND...NEAR
THE EDGE OF A STRONG CAPPING INVERSION. MLCAPES ARE PROGGED OVER
4000 J/KG INTO NC SD...AND AROUND 3000 J/KG IN SE ND. EXPECT
STORMS TO DEVELOP QUICKLY IN SD ONCE THE CAP BREAKS...AND MOVE
NORTH AND EAST INTO THE AREA SATURDAY NIGHT AND SUNDAY. SOME
STORMS COULD BE SEVERE SATURDAY NIGHT INTO SUNDAY...BUT LOCALLY
HEAVY RAIN IS POSSIBLE WITH PWATS RISING TO AROUND 1.5 INCHES OR
EVEN A BIT HIGHER. WE HAVE ISSUED AN ESF FOR SOME LOCALIZED
FLOODING POSSIBLE IF TRAINING ECHOES OCCUR WITH A PARALLEL UPPER
BOUNDARY.

SAME SCENARIO IN PLACE FOR EXTENDED...AFTER A WEEKEND OF RAIN AND
THUNDERSTORMS...UPPER LOW LIKELY TO BE LOCATED OVER AN AREA ANYWHERE
FROM SOUTHEAST NORTH DAKOTA TO IOWA. MOISTURE WILL STILL BE
TRANSPORTED CYCLONICALLY AROUND THIS STACKED SYSTEM CONTINUING
SHOWERS WITH THE POSSIBILITY OF SOME THUNDER. ORIENTATION OF
BOUNDARY AND ASSOCIATED CONVECTIVE PARAMETERS MAKE MONDAY THE MORE
LIKELY TIME FOR THUNDER ACTIVITY...LESS SO ON TUESDAY AND BY
WEDNESDAY PRECIPITATION SHOULD BE MORE SHOWERY OR EVEN JUST SOME
STRATIFORM RAIN. GOING POP FREE FINALLY BY THURSDAY AS AN OMEGA
BLOCK DEVELOPS WITH NORTHERN PLAINS UNDER THE RIDGE PART OF THE
BLOCK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1150 PM CDT THU MAY 16 2013

VFR CONDITIONS AND SLOWLY DIMINISHING LIGHT RA OVER
KDVL...KGFK...AND KTVF WILL CONTINUE FOR THE REST OF THE NIGHT.
SOME MVFR CONDITIONS WILL BE POSSIBLE AT KDVL AND POSSIBLY FURTHER
EAST.  WINDS WILL STAY EAST AROUND 10 KTS.

&&

.HYDROLOGY...
ISSUED AT 310 PM CDT THU MAY 16 2013

THE NORTHERN PORTION OF THE RED RIVER CONTINUES TO SEE RIVER LEVELS
UNDERGO RECESSION AT DRAYTON AND PEMBINA. THIS IS THE LAST REMNANT
OF THE SNOWMELT WATER SURGE CONTINUING TO MOVE NORTHWARD INTO
CANADA.

A PROLONGED PERIOD OF UNSETTLED WEATHER IS EXPECTED TO BEGIN THIS
EVENING AND CONTINUE THROUGH TUESDAY. CUMULATIVE RAINFALL TOTALS OF
2 TO 4 INCHES ACROSS THE RED RIVER BASIN...WITH LOCALLY HIGHER
AMOUNTS...WILL BE POSSIBLE BY TUESDAY MORNING. LOCALIZED FLASH
FLOODING IS A POSSIBILITY OVER THE WEEKEND DUE TO TRAINING
THUNDERSTORMS. IN ADDITION...DESPITE SOME RAINFALL INFILTRATION
DUE TO PATCHY DRY TOPSOIL...ENOUGH RUNOFF MAY OCCUR TO CAUSE SOME
SMALLER TRIBUTARIES TO RISE BACK ABOVE FLOOD STAGE NEXT WEEK. AS A
RESULT...A HYDROLOGIC OUTLOOK HAS BEEN ISSUED TO HIGHLIGHT THE
SITUATION.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

UPDATE...JR
SHORT TERM...DK
LONG TERM...WJB/DK
AVIATION...JR
HYDROLOGY...BRAMER

000
FXUS63 KBIS 170316
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
1016 PM CDT THU MAY 16 2013

.UPDATE...
ISSUED AT 1016 PM CDT THU MAY 16 2013

ADJUSTED EVENING POPS DOWNWARD BASED ON CURRENT RADAR OBS/TRENDS.
OTHERWISE...NOT TOO MANY CHANGES WERE MADE TO THE ONGOING
FORECAST. THE UPDATED GRIDDED AND TEXT PRODUCTS HAVE BEEN SENT.

UPDATE ISSUED AT 718 PM CDT THU MAY 16 2013

REGIONAL RADAR TRENDS INDICATE NUMEROUS SHOWERS ACROSS THE JAMES
RIVER BASIN CONTINUING TO PUSH EAST OF THE CWA THIS EVENING. WITH
THE ATMOSPHERE PRETTY WELL WORKED OVER...DECREASED POPS WEST AND
CENTRAL THROUGH THE REMAINDER OF THE EVENING HOURS.

HOWEVER...SHORT RANGE MODEL GUIDANCE CONTINUES TO PROG INCREASING PRECIP
CHANCES AFTER MIDNIGHT AS AN UPPER WAVE APPROACHES FROM THE
SOUTHWEST. SHOWALTER INDICES INDICATE THUNDER POTENTIAL DEVELOPING
ACROSS SOUTHWESTERN NORTH DAKOTA AFTER MIDNIGHT. AS A
RESULT...REMOVED THUNDER AREAWIDE TONIGHT AND ONLY INDICATED
ISOLATED THUNDER SOUTHWEST DEVELOPING AFTER MIDNIGHT.

UPDATED THE HOURLY SENSIBLE WEATHER GRIDS BASED ON CURRENT
OBS/TRENDS. THE UPDATED GRIDDED AND TEXT PRODUCTS HAVE BEEN SENT.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 300 PM CDT THU MAY 16 2013

LATEST WATER VAPOR IMAGERY SHOWS A SOUTHWEST FLOW INTO NORTH DAKOTA
AHEAD OF AN UPPER TROUGH WHICH IS SLIDING INTO THE NORTHWEST COAST.
FOR THE NEAR TERM...THROUGH THURSDAY EVENING...CATEGORICAL POPS
WILL CONTINUE FROM BLAT TO MCCLUSKY INTO BISMARCK AND AREAS TO
THE EAST AS A SHORTWAVE PROPAGATES THROUGH. THERE IS A BREAK IN
THE CLOUDS AND PRECIPITATION IN THE FAR WEST WITH MORE SHORTWAVES
MOVING INTO CENTRAL MONTANA. THESE WILL MOVE THROUGH TONIGHT INTO
FRIDAY GENERATING ISOLATED TO SCATTERED SHOWERS. BEST CHANCE FOR
AN ISOLATED THUNDERSTORM WILL RESIDE IN THE WEST AND SOUTH INTO
TONIGHT. LATEST VISIBLE IMAGERY SHOWS SOME CLEARING IN THE WEST
WITH CLOUDS BEGINNING TO BILLOW UP IN NORTHEAST MONTANA. FOR
FRIDAY...SOME INSTABILITY CONTINUES IN THE SOUTHWEST AND FAR SOUTH
CENTRAL FOR A MENTION OF THUNDERSTORMS...OTHERWISE SCATTERED
SHOWERS WILL GENERALLY BE THE RULE.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 PM CDT THU MAY 16 2013

A BROADENING UPPER LEVEL LOW POSITIONED OVER THE WESTERN CONUS EARLY
THE EXTENDED WILL ALLOW FOR MOIST SOUTHWESTERLY FLOW TO CONTINUE
ACROSS THE NORTHERN PLAINS SATURDAY INTO SUNDAY. AS THIS BROAD UPPER
LEVEL TROUGH SLOWLY SHIFTS EAST AND OVER THE REGION LATE SUNDAY AND
EARLY MONDAY THE FLOW WILL BECOME SOUTHERLY AS THE UPPER LEVEL
TROUGH CLOSES OFF OVER THE DAKOTAS. IT WILL REMAIN OVERHEAD MONDAY
AND TUESDAY BEFORE MOVING EAST THEREAFTER. 12Z GFS/GEM/NAM/ECWMF ARE
IN GOOD AGREEMENT REGARDING THIS PATTERN...BEFORE SOLUTIONS DIVERGE
LATE IN THE EXTENDED AS THE UPPER LEVEL LOW MOVES EAST.

THE MAIN ISSUE FOR THE EXTENDED WILL BE THE POTENTIAL FOR HEAVY RAIN
THROUGH EARLY NEXT WEEK. THERE IS DECENT AGREEMENT BETWEEN THE 12Z
MODEL RUNS REGARDING THE PLACEMENT AND AMOUNT OF PRECIPITATION
ACROSS THE AREA...WITH THE HEAVIEST AMOUNTS FOCUSED ON THE JAMES
RIVER VALLEY AND POINTS EAST. A SECOND AREA OF HEAVY PRECIPITATION
MAY BE POSSIBLE ACROSS THE NORTHWEST. HOWEVER...THERE IS A BIT
MORE UNCERTAINTY FOR THE NORTHWEST AREA. IN ADDITION...THE 12Z
GFS AND NAM CONTINUE TO PLACE PRECIPITABLE WATER VALUES OF 1.30 TO
1.50 INCHES ACROSS THE EASTERN TWO THIRDS OF NORTH DAKOTA SATURDAY
THROUGH EARLY SUNDAY MORNING. ACCORDING TO PW CLIMATOLOGY...THESE
FORECAST VALUES WILL BE IN THE 99TH PERCENTILE TO THE HIGHEST EVER
OBSERVED FOR THE MONTH OF MAY. CONFIDENCE IS INCREASING FOR 1 TO 2
INCHES (WITH LOCALLY HIGHER AMOUNTS ACROSS THE JAMES RIVER VALLEY)
OF RAINFALL THROUGH SUNDAY EVENING. ADDITIONAL LIGHT TO MODERATE
RAIN WILL CONTINUE THROUGH TUESDAY AS THE UPPER LEVEL LOW IS
OVERHEAD...BRINGING POTENTIAL RAINFALL TOTALS THROUGH TUESDAY INTO
THE 2 TO 4 INCH RANGE. THIS WILL HAVE TO BE MONITORED CLOSELY OVER
THE NEXT FEW DAYS AS POTENTIAL HYDRO ISSUES FOR THE JAMES RIVER
MAY COME INTO PLAY. ALSO...THIS HEAVY RAIN EVENT WILL POTENTIALLY
ALLEVIATE THE RAINFALL DEFICITS OBSERVED SO FAR FOR MAY.

REGARDING THE POTENTIAL FOR SEVERE WEATHER...THE BEST CHANCES FOR
ANY SEVERE WEATHER WILL COME SATURDAY AFTERNOON THROUGH EARLY SUNDAY
MORNING FOR LOCATIONS EAST OF STATE HIGHWAY 83 AND SOUTH OF
INTERSTATE 94. ISOLATED SEVERE MAY BE POSSIBLE FOR THE SOUTHWEST
LATE SATURDAY AFTERNOON AND EARLY EVENING. SUFFICIENT MOISTURE
WILL BE PRESENT DUE TO PREVIOUS MOISTURE RECEIVED ON THURSDAY AND
FRIDAY. BULK SHEAR VALUES WILL BE IN THE 40 TO 50 KT RANGE DURING
THIS PERIOD...WITH ML CAPE IN THE 1000 TO 2000 J/KG RANGE FOR THE
FAR SOUTH CENTRAL...AND 2000 TO 3000 J/LG VALUES ACROSS THE
SOUTHERN JAMES RIVER VALLEY. MU CAPE VALUES WILL BE IN THE 1200 TO
3000 J/KG RANGE AS WELL. HOWEVER...THE MAIN LIMITING FACTOR WILL
BE THE WARM AIR ALOFT...AS THE NAM/GFS BUFR SOUNDINGS FOR JMS/BIS
DEPICT A DECENT CAP INVERSION. THIS MAY BE OVERCOME BY DAYTIME
HEATING AND LARGE SCALE ASCENT ASSOCIATED WITH THE AFOREMENTIONED
UPPER LEVEL TROUGH.

BEYOND TUESDAY...THE UPPER LEVEL LOW WILL MOVE EAST AND IN ITS
WAKE...UPPER LEVEL RIDING WILL COMMENCE. A PERIOD OF DRIER AND
SEASONABLE TEMPERATURES ARE FORECAST FOR WEDNESDAY AND THURSDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 24Z FRIDAY EVENING)
ISSUED AT 718 PM CDT THU MAY 16 2013

MVFR CIGS ACROSS SOUTHWESTERN NORTH DAKOTA WILL GRADUALLY SPREAD
NORTHEAST OVER THE STATE TONIGHT. IFR CIGS ARE EXPECTED TO DEVELOP
OVER KDIK AROUND MIDNIGHT...THEN IMPROVE TO MVFR MIDDAY FRIDAY.

AN UNSETTLED WEATHER PATTERN WILL GENERATE CHANCES FOR SHOWERS AND
POSSIBLE THUNDERSTORMS PRIMARILY AFTER SUNRISE FRIDAY. THE THREAT
FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE REMAINDER
OF THE TAF PERIOD.


&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

UPDATE...TM
SHORT TERM...KS
LONG TERM...LTH
AVIATION...TM