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000
FXUS63 KGRR 010730
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
330 AM EDT MON SEP 1 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE

.SYNOPSIS...
ISSUED AT 330 AM EDT MON SEP 1 2014

A COLD FRONT WILL MOVE INTO THE GREAT LAKES REGION FROM THE WEST
LATER TODAY AND INTO TONIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED
TO DEVELOP OVER SOUTHWEST LOWER MICHIGAN FROM THE LATE MORNING HOURS
PERSISTING INTO THE EVENING. SOME OF THE STORMS FROM THE MIDDAY
HOURS THROUGH THE EVENING MAY BE SEVERE WITH LARGE HAIL AND STRONG
WINDS. SHOWERS AND STORMS WILL GRADUALLY TAPER OFF TONIGHT
FROM NORTH TO SOUTH AS THE FRONT DROPS SOUTHWARD INTO INDIANA. DRY
WEATHER IS THEN EXPECTED FOR THE MOST PART FROM TUESDAY THROUGH
WEDNESDAY. CHANCES FOR SHOWERS AND STORMS INCREASE ONCE AGAIN
WEDNESDAY NIGHT THROUGH FRIDAY AS A LOW PRESSURE SYSTEM TRAVERSES
THE AREA. TEMPERATURES THIS WEEK WILL BE NEAR TO ABOVE NORMAL WITH
HIGHS IN THE UPPER 70S TO 80S ALL WEEK. A COOL DOWN IS EXPECTED NEXT
WEEKEND BEHIND A COLD FRONT THAT MOVES THROUGH ON FRIDAY.

&&

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT MON SEP 1 2014

MAIN FORECAST ISSUE IS DETERMINING THE THREAT FOR SEVERE WEATHER
TODAY FROM LATE MORNING INTO THE EVENING HOURS. FEEL THE THREAT FOR
SEVERE WEATHER IS THERE TODAY...BUT IT IS NOT A CERTAINTY BY ANY
MEANS. THERE ARE FACTORS BOTH FOR AND AGAINST SEVERE STORMS TODAY.
HOWEVER...THERE IS ENOUGH GOING FOR IT TO CONTINUE TO FORECAST THE
THREAT.

IN TERMS OF THE PARAMETERS THAT ARE GOING FOR THIS EVENT...WE HAVE A
STRONG SHORTWAVE PIVOTING OUR DIRECTION FROM THE PLAINS. THIS WILL
RESULT IN SOLID WIND FIELDS...30-35 KNOT LLJ...40-55 KNOT MID LEVEL
JET RESULTING IN 0-6KM SHEAR ON THE ORDER OF 40 KNOTS THIS
AFTERNOON. SO...WIND FIELDS WILL BE STRONG ENOUGH FOR SEVERE WEATHER
AND THE DEEP LAYER SHEAR IS FAVORABLE FOR ORGANIZATION. SURFACE DEW
POINT SHOULD SURGE BACK INTO THE LOWER 70S AT MOST PLACES THIS
AFTERNOON. ALSO...SOLID 850MB MOISTURE TRANSPORT IS ONGOING FROM 15Z
THROUGH 00Z OR SO.

THE QUESTION MARKS WITH THIS EVENT ARE THAT THE MAIN SHORTWAVE IS
PIVOTING NORTHEAST TOWARDS LAKE SUPERIOR...AS WELL AS THE AREA BEING
IN THE RIGHT EXIT REGION OF THE UPPER LEVEL JET. HENCE...THE BEST
DYNAMICS WILL BE NORTH OF OUR AREA TODAY. INSTABILITY IS A QUESTION
GIVEN THE AMOUNT OF DEBRIS CLOUDS THAT WILL BE TRYING TO PRESS IN
FROM THE WEST AS WELL AS THE FACT THAT THE EVENT MAY GET GOING
BEFORE PEAK HEATING. FEEL THE LOW LEVEL MOISTURE ADVECTION COUPLED
WITH MID LEVEL COOLING SHOULD PROVIDE DECENT CAPE VALUES THOUGH ON
THE ORDER OF 1000-2000 J/KG.

SHORT TERM CONVECTION ALLOWING MODELS ALL SHOW SOME ACTIVITY
SWEEPING EAST THROUGH THE FORECAST AREA FROM MIDDAY THROUGH THE
EVENING (NOON THROUGH 800 PM). FEEL THE BIGGEST THREAT FROM STORMS
TODAY IN OUR AREA WILL BE STRONG WINDS GIVEN THE WIND FIELDS IN
PLACE. NOT A SLAM DUNK BY ANY MEANS BUT WE WILL BE MONITORING STORMS
THROUGH THE EVENING FOR THE POTENTIAL FOR SEVERE WX. THE MODELS ALSO
SHOW SOMEWHAT OF LAKE SHADOW TO THE CONVECTION...BUT THIS MAY BE
MORE RELATED TO OUR LOCATION SOUTH OF THE BEST DYNAMICS.

OTHERWISE...THE SHORT TERM IS RELATIVELY QUIET. ANY STORMS THIS
EVENING SHOULD WORK SOUTH OF THE AREA OVERNIGHT. NOT OUT OF THE
REALM OF POSSIBILITIES FOR A FEW SHOWERS ON TUESDAY...BUT FELT THE
THREAT WAS SMALL ENOUGH TO GO DRY. TUESDAY NIGHT AND WEDNESDAY
SHOULD BE DRY WITH RIDGING IN PLACE AT THE SURFACE.

.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 330 AM EDT MON SEP 1 2014

THE MOST UNSETTLED WEATHER IN THE LONG TERM LOOKS TO OCCUR IN THE
FIRST COUPLE OF DAYS...FROM THE BEGINNING OF THE PERIOD WED NIGHT
INTO FRI NIGHT. THE LATEST TREND IS FOR A LITTLE MORE POSSIBLE PCPN
WED NIGHT INTO THU WITH THE PASSAGE OF THE WARM FRONT THROUGH THE
AREA. THIS LOOKS TO BE THE CASE DUE TO THE GRADIENT/LOW LEVEL JET
EXPECTED TO BE A LITTLE STRONGER WITH A STRONGER TROUGH MOVING IN.
HOW QUICKLY THE FRONT MOVES THROUGH WILL DICTATE HOW WARM WE GET ON
THU. IF THE FRONT MOVES QUICK ENOUGH...WE COULD HAVE A CHC TO WARM
TOWARD 90 WITH H850 TEMPS OF 20C ADVECTING IN. FOR NOW...WE HAVE
SETTLED WITH THE MID-UPPER 80S WITH THE UNCERTAINTY OF THE PCPN.

WE WILL SEE ANOTHER BATCH OF CONVECTION BE POSSIBLE THEN CENTERED
AROUND FRI AS THE COLD FRONT PUSHES THROUGH AND ENCOUNTERING THE
VERY WARM AND MOIST AIR MASS. WE COULD HAVE SOME ASSISTANCE VIA THE
RRQ OF AN UPPER JET TO OUR N/NE THAT WOULD SUPPLEMENT THE COLD
FRONTAL PASSAGE.

THE REMAINDER OF THE LONG TERM FROM SAT THROUGH SUN LOOKS TO BE
RATHER QUIET...YET COOL. WE WILL SEE A CANADIAN AIR MASS FILTER IN
BEHIND THE THU/FRI SYSTEM WITH A DECENT NNE LOW LEVEL FLOW USHERING
IT IN. THE UPPER FLOW WILL BE FROM THE NW AND A BIT OF A TROUGH WILL
BE OVER THE AREA. THE FAR ERN FLANK OF A SFC RIDGE WILL BE
BUILDING IN AS THE SYNOPTIC PATTERN OVER THE COUNTRY WILL FEATURE A
FAIRLY BROAD/EXPANSIVE UPPER RIDGE FROM THE ERN PACIFIC INTO THE
ROCKIES. THIS SHOULD KEEP THE AREA DRY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 149 AM EDT MON SEP 1 2014

THERE ARE A FEW ITEMS THAT COULD IMPACT AVIATION OPERATIONS OVER
THE NEXT 24 HOURS ACROSS SW LOWER MI. THE FIRST ITEM IS FOG
POTENTIAL. A DECENT AMOUNT OF LOW LEVEL MOISTURE REMAINS IN
PLACE THIS MORNING AND TEMPS AND DEW POINTS ARE CLOSE ALREADY. THE
BEST CHC FOR FOG AND SOME POSSIBLE STRATUS WILL BE ALONG AND SE OF
I-69 WHERE A FEW SHOWERS WERE PRESENT EARLIER AND WHERE THE
MOISTURE HAS HUNG IN THE MOST. CAN NOT RULE OUT SOME NEAR KGRR AND
KAZO...BUT THE FURTHER WEST THE WINDS WILL REMAIN UP AND LIMIT FOG
POTENTIAL.

THE NEXT THING IS THE POTENTIAL FOR PCPN TODAY. MOST DATA
INDICATES THAT WHATEVER IS LEFT OF THE LINE OF SHOWERS/STORMS NEAR
THE MISSISSIPPI RIVER AS OF 0545Z WILL MOVE INTO THE AREA
TOWARD 15Z OR SO. IT WILL INITIALLY FALL APART WITH LESS CHC OF
IMPACTS FROM IT TOWARD THE LAKESHORE. AS IT ENCOUNTERS SOME
DIURNAL INSTABILITY TOWARD THE EAST...WE EXPECT IT TO REINTENSIFY
INTO A LINE OF STORMS BY THE TIME IT REACHES U.S.-127 BY 19Z OR
SO. BEST CHC FOR LOWER CONDITIONS WILL BE ACROSS THE EAST WHERE
IFR WOULD BE LIKELY IN HEAVY RAINFALL. THIS CAN BE FINE TUNED
CLOSER TO THE EVENT.

ONCE THE LINE OF STORMS MOVES EAST...THERE SHOULD BE SOMEWHAT OF A
BREAK. ANOTHER PERIOD OF SOME SHOWERS WILL BE POSSIBLE WITH THE
WAVE TOWARD 00Z AND AFTER THAT.

&&

.MARINE...
ISSUED AT 330 AM EDT MON SEP 1 2014

WE WILL BE KEEPING THE SMALL CRAFT ADVISORY AND BEACH HAZARDS
HEADLINES AS IS FOR THIS FCST CYCLE. WINDS WILL BE RAMPING UP THIS
MORNING AS THE SW GRADIENT STRENGTHENS OUT AHEAD OF THE INCOMING
COLD FRONT. THE WINDS AND WAVES SHOULD PEAK MID TO LATE AFTERNOON
BEFORE THEN COMING DOWN QUICKLY THIS EVENING AS THE GRADIENT WEAKENS
WITH THE ACTUAL FRONT.

THE NEXT POSSIBLE SET OF HEADLINES THAT MAY BE NEEDED FOR THE
NEARSHORE WATERS LOOKS TO START IN THE WED NIGHT/THU TIME FRAME AS
THE FLOW STRENGTHENS WITH A SURGE OF WARMER AIR WITH THE NEXT
FRONTAL SYSTEM POISED TO MOVE IN.

&&

.HYDROLOGY...
ISSUED AT 330 AM EDT MON SEP 1 2014

LOCALLY HEAVY RAIN IS CERTAINLY POSSIBLE TODAY GIVEN PRECIPITABLE
WATER VALUES SURGING TOWARDS 2 INCHES THIS AFTERNOON. THE RAIN WILL
BE CONVECTIVE IN NATURE THOUGH...SO ANY HEAVY RAIN WILL OCCUR IN
SWATHS AS OPPOSED TO BEING WIDESPREAD. RIVER LEVELS ARE ALL WITHIN
BANK...AND FORECAST BASIN AVERAGE RAINFALL AMOUNTS ARE ON THE ORDER
OF 0.20 TO 0.50 INCHES. THESE AMOUNTS SHOULD BE ABLE TO BE ABSORBED
BY THE RIVER SYSTEMS WITHOUT MUCH ISSUE.

TODAY/S ISSUE THOUGH WILL BE MONITORING THE SWATHS OF HEAVIER RAIN
THAT SWEEP THROUGH WITH THE STORMS. THINKING THE MOTION WILL BE
QUICK ENOUGH (NORTHEAST AT 35-45 MPH)...TO PREVENT MUCH OF AN ISSUE
WITH FLASH FLOODING.

NEXT GOOD CHANCE FOR RAIN WILL COME LATER THIS WEEK WITH A WARM
FRONT WEDNESDAY NIGHT INTO THURSDAY MORNING AND AGAIN FRIDAY AHEAD
OF A COLD FRONT. TOTAL RAINFALL WITH THIS SYSTEM COULD BE ON THE
ORDER OF A HALF INCH TO AN INCH.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM 10 AM EDT THIS MORNING THROUGH
     THIS EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 10 PM EDT THIS
     EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...DUKE
SHORT TERM...DUKE
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...DUKE
MARINE...NJJ







000
FXUS63 KGRR 010730
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
330 AM EDT MON SEP 1 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE

.SYNOPSIS...
ISSUED AT 330 AM EDT MON SEP 1 2014

A COLD FRONT WILL MOVE INTO THE GREAT LAKES REGION FROM THE WEST
LATER TODAY AND INTO TONIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED
TO DEVELOP OVER SOUTHWEST LOWER MICHIGAN FROM THE LATE MORNING HOURS
PERSISTING INTO THE EVENING. SOME OF THE STORMS FROM THE MIDDAY
HOURS THROUGH THE EVENING MAY BE SEVERE WITH LARGE HAIL AND STRONG
WINDS. SHOWERS AND STORMS WILL GRADUALLY TAPER OFF TONIGHT
FROM NORTH TO SOUTH AS THE FRONT DROPS SOUTHWARD INTO INDIANA. DRY
WEATHER IS THEN EXPECTED FOR THE MOST PART FROM TUESDAY THROUGH
WEDNESDAY. CHANCES FOR SHOWERS AND STORMS INCREASE ONCE AGAIN
WEDNESDAY NIGHT THROUGH FRIDAY AS A LOW PRESSURE SYSTEM TRAVERSES
THE AREA. TEMPERATURES THIS WEEK WILL BE NEAR TO ABOVE NORMAL WITH
HIGHS IN THE UPPER 70S TO 80S ALL WEEK. A COOL DOWN IS EXPECTED NEXT
WEEKEND BEHIND A COLD FRONT THAT MOVES THROUGH ON FRIDAY.

&&

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT MON SEP 1 2014

MAIN FORECAST ISSUE IS DETERMINING THE THREAT FOR SEVERE WEATHER
TODAY FROM LATE MORNING INTO THE EVENING HOURS. FEEL THE THREAT FOR
SEVERE WEATHER IS THERE TODAY...BUT IT IS NOT A CERTAINTY BY ANY
MEANS. THERE ARE FACTORS BOTH FOR AND AGAINST SEVERE STORMS TODAY.
HOWEVER...THERE IS ENOUGH GOING FOR IT TO CONTINUE TO FORECAST THE
THREAT.

IN TERMS OF THE PARAMETERS THAT ARE GOING FOR THIS EVENT...WE HAVE A
STRONG SHORTWAVE PIVOTING OUR DIRECTION FROM THE PLAINS. THIS WILL
RESULT IN SOLID WIND FIELDS...30-35 KNOT LLJ...40-55 KNOT MID LEVEL
JET RESULTING IN 0-6KM SHEAR ON THE ORDER OF 40 KNOTS THIS
AFTERNOON. SO...WIND FIELDS WILL BE STRONG ENOUGH FOR SEVERE WEATHER
AND THE DEEP LAYER SHEAR IS FAVORABLE FOR ORGANIZATION. SURFACE DEW
POINT SHOULD SURGE BACK INTO THE LOWER 70S AT MOST PLACES THIS
AFTERNOON. ALSO...SOLID 850MB MOISTURE TRANSPORT IS ONGOING FROM 15Z
THROUGH 00Z OR SO.

THE QUESTION MARKS WITH THIS EVENT ARE THAT THE MAIN SHORTWAVE IS
PIVOTING NORTHEAST TOWARDS LAKE SUPERIOR...AS WELL AS THE AREA BEING
IN THE RIGHT EXIT REGION OF THE UPPER LEVEL JET. HENCE...THE BEST
DYNAMICS WILL BE NORTH OF OUR AREA TODAY. INSTABILITY IS A QUESTION
GIVEN THE AMOUNT OF DEBRIS CLOUDS THAT WILL BE TRYING TO PRESS IN
FROM THE WEST AS WELL AS THE FACT THAT THE EVENT MAY GET GOING
BEFORE PEAK HEATING. FEEL THE LOW LEVEL MOISTURE ADVECTION COUPLED
WITH MID LEVEL COOLING SHOULD PROVIDE DECENT CAPE VALUES THOUGH ON
THE ORDER OF 1000-2000 J/KG.

SHORT TERM CONVECTION ALLOWING MODELS ALL SHOW SOME ACTIVITY
SWEEPING EAST THROUGH THE FORECAST AREA FROM MIDDAY THROUGH THE
EVENING (NOON THROUGH 800 PM). FEEL THE BIGGEST THREAT FROM STORMS
TODAY IN OUR AREA WILL BE STRONG WINDS GIVEN THE WIND FIELDS IN
PLACE. NOT A SLAM DUNK BY ANY MEANS BUT WE WILL BE MONITORING STORMS
THROUGH THE EVENING FOR THE POTENTIAL FOR SEVERE WX. THE MODELS ALSO
SHOW SOMEWHAT OF LAKE SHADOW TO THE CONVECTION...BUT THIS MAY BE
MORE RELATED TO OUR LOCATION SOUTH OF THE BEST DYNAMICS.

OTHERWISE...THE SHORT TERM IS RELATIVELY QUIET. ANY STORMS THIS
EVENING SHOULD WORK SOUTH OF THE AREA OVERNIGHT. NOT OUT OF THE
REALM OF POSSIBILITIES FOR A FEW SHOWERS ON TUESDAY...BUT FELT THE
THREAT WAS SMALL ENOUGH TO GO DRY. TUESDAY NIGHT AND WEDNESDAY
SHOULD BE DRY WITH RIDGING IN PLACE AT THE SURFACE.

.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 330 AM EDT MON SEP 1 2014

THE MOST UNSETTLED WEATHER IN THE LONG TERM LOOKS TO OCCUR IN THE
FIRST COUPLE OF DAYS...FROM THE BEGINNING OF THE PERIOD WED NIGHT
INTO FRI NIGHT. THE LATEST TREND IS FOR A LITTLE MORE POSSIBLE PCPN
WED NIGHT INTO THU WITH THE PASSAGE OF THE WARM FRONT THROUGH THE
AREA. THIS LOOKS TO BE THE CASE DUE TO THE GRADIENT/LOW LEVEL JET
EXPECTED TO BE A LITTLE STRONGER WITH A STRONGER TROUGH MOVING IN.
HOW QUICKLY THE FRONT MOVES THROUGH WILL DICTATE HOW WARM WE GET ON
THU. IF THE FRONT MOVES QUICK ENOUGH...WE COULD HAVE A CHC TO WARM
TOWARD 90 WITH H850 TEMPS OF 20C ADVECTING IN. FOR NOW...WE HAVE
SETTLED WITH THE MID-UPPER 80S WITH THE UNCERTAINTY OF THE PCPN.

WE WILL SEE ANOTHER BATCH OF CONVECTION BE POSSIBLE THEN CENTERED
AROUND FRI AS THE COLD FRONT PUSHES THROUGH AND ENCOUNTERING THE
VERY WARM AND MOIST AIR MASS. WE COULD HAVE SOME ASSISTANCE VIA THE
RRQ OF AN UPPER JET TO OUR N/NE THAT WOULD SUPPLEMENT THE COLD
FRONTAL PASSAGE.

THE REMAINDER OF THE LONG TERM FROM SAT THROUGH SUN LOOKS TO BE
RATHER QUIET...YET COOL. WE WILL SEE A CANADIAN AIR MASS FILTER IN
BEHIND THE THU/FRI SYSTEM WITH A DECENT NNE LOW LEVEL FLOW USHERING
IT IN. THE UPPER FLOW WILL BE FROM THE NW AND A BIT OF A TROUGH WILL
BE OVER THE AREA. THE FAR ERN FLANK OF A SFC RIDGE WILL BE
BUILDING IN AS THE SYNOPTIC PATTERN OVER THE COUNTRY WILL FEATURE A
FAIRLY BROAD/EXPANSIVE UPPER RIDGE FROM THE ERN PACIFIC INTO THE
ROCKIES. THIS SHOULD KEEP THE AREA DRY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 149 AM EDT MON SEP 1 2014

THERE ARE A FEW ITEMS THAT COULD IMPACT AVIATION OPERATIONS OVER
THE NEXT 24 HOURS ACROSS SW LOWER MI. THE FIRST ITEM IS FOG
POTENTIAL. A DECENT AMOUNT OF LOW LEVEL MOISTURE REMAINS IN
PLACE THIS MORNING AND TEMPS AND DEW POINTS ARE CLOSE ALREADY. THE
BEST CHC FOR FOG AND SOME POSSIBLE STRATUS WILL BE ALONG AND SE OF
I-69 WHERE A FEW SHOWERS WERE PRESENT EARLIER AND WHERE THE
MOISTURE HAS HUNG IN THE MOST. CAN NOT RULE OUT SOME NEAR KGRR AND
KAZO...BUT THE FURTHER WEST THE WINDS WILL REMAIN UP AND LIMIT FOG
POTENTIAL.

THE NEXT THING IS THE POTENTIAL FOR PCPN TODAY. MOST DATA
INDICATES THAT WHATEVER IS LEFT OF THE LINE OF SHOWERS/STORMS NEAR
THE MISSISSIPPI RIVER AS OF 0545Z WILL MOVE INTO THE AREA
TOWARD 15Z OR SO. IT WILL INITIALLY FALL APART WITH LESS CHC OF
IMPACTS FROM IT TOWARD THE LAKESHORE. AS IT ENCOUNTERS SOME
DIURNAL INSTABILITY TOWARD THE EAST...WE EXPECT IT TO REINTENSIFY
INTO A LINE OF STORMS BY THE TIME IT REACHES U.S.-127 BY 19Z OR
SO. BEST CHC FOR LOWER CONDITIONS WILL BE ACROSS THE EAST WHERE
IFR WOULD BE LIKELY IN HEAVY RAINFALL. THIS CAN BE FINE TUNED
CLOSER TO THE EVENT.

ONCE THE LINE OF STORMS MOVES EAST...THERE SHOULD BE SOMEWHAT OF A
BREAK. ANOTHER PERIOD OF SOME SHOWERS WILL BE POSSIBLE WITH THE
WAVE TOWARD 00Z AND AFTER THAT.

&&

.MARINE...
ISSUED AT 330 AM EDT MON SEP 1 2014

WE WILL BE KEEPING THE SMALL CRAFT ADVISORY AND BEACH HAZARDS
HEADLINES AS IS FOR THIS FCST CYCLE. WINDS WILL BE RAMPING UP THIS
MORNING AS THE SW GRADIENT STRENGTHENS OUT AHEAD OF THE INCOMING
COLD FRONT. THE WINDS AND WAVES SHOULD PEAK MID TO LATE AFTERNOON
BEFORE THEN COMING DOWN QUICKLY THIS EVENING AS THE GRADIENT WEAKENS
WITH THE ACTUAL FRONT.

THE NEXT POSSIBLE SET OF HEADLINES THAT MAY BE NEEDED FOR THE
NEARSHORE WATERS LOOKS TO START IN THE WED NIGHT/THU TIME FRAME AS
THE FLOW STRENGTHENS WITH A SURGE OF WARMER AIR WITH THE NEXT
FRONTAL SYSTEM POISED TO MOVE IN.

&&

.HYDROLOGY...
ISSUED AT 330 AM EDT MON SEP 1 2014

LOCALLY HEAVY RAIN IS CERTAINLY POSSIBLE TODAY GIVEN PRECIPITABLE
WATER VALUES SURGING TOWARDS 2 INCHES THIS AFTERNOON. THE RAIN WILL
BE CONVECTIVE IN NATURE THOUGH...SO ANY HEAVY RAIN WILL OCCUR IN
SWATHS AS OPPOSED TO BEING WIDESPREAD. RIVER LEVELS ARE ALL WITHIN
BANK...AND FORECAST BASIN AVERAGE RAINFALL AMOUNTS ARE ON THE ORDER
OF 0.20 TO 0.50 INCHES. THESE AMOUNTS SHOULD BE ABLE TO BE ABSORBED
BY THE RIVER SYSTEMS WITHOUT MUCH ISSUE.

TODAY/S ISSUE THOUGH WILL BE MONITORING THE SWATHS OF HEAVIER RAIN
THAT SWEEP THROUGH WITH THE STORMS. THINKING THE MOTION WILL BE
QUICK ENOUGH (NORTHEAST AT 35-45 MPH)...TO PREVENT MUCH OF AN ISSUE
WITH FLASH FLOODING.

NEXT GOOD CHANCE FOR RAIN WILL COME LATER THIS WEEK WITH A WARM
FRONT WEDNESDAY NIGHT INTO THURSDAY MORNING AND AGAIN FRIDAY AHEAD
OF A COLD FRONT. TOTAL RAINFALL WITH THIS SYSTEM COULD BE ON THE
ORDER OF A HALF INCH TO AN INCH.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM 10 AM EDT THIS MORNING THROUGH
     THIS EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 10 PM EDT THIS
     EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...DUKE
SHORT TERM...DUKE
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...DUKE
MARINE...NJJ






000
FXUS63 KGRR 010549
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
149 AM EDT MON SEP 1 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 322 PM EDT SUN AUG 31 2014

A WEAK AREA OF HIGH PRESSURE WILL KEEP MUCH OF THE REGION DRY INTO
THE EVENING. A COLD FRONT WILL APPROACH FROM THE WEST ON LABOR DAY
TRIGGERING SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL RETURN
FOR TUESDAY DRYING THE REGION OUT.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 322 PM EDT SUN AUG 31 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE POTENTIAL FOR
SEVERE WEATHER ON MONDAY. OVERALL THE POTENTIAL STILL EXISTS.

ONE POTENTIAL LIMITING FACTOR WILL BE WHAT IMPACTS THE DECAYING
AREA OF THUNDERSTORMS WILL HAVE AS IT MOVES IN FROM THE WEST
MONDAY MORNING. THE HRRR RUC SHOWS THIS SYSTEM WEAKENING WELL
BEFORE IT ARRIVES IN MI...SO I AM THINKING THIS WILL HAVE A
MINIMAL IMPACT ON THE POTENTIAL INSTABILITY MONDAY. THE
COMBINATION OF HEATING AND MOISTURE ADVECTION SUPPORTS CAPE OVER
1500 J/KG ON MONDAY. DEEP LAYER SHEAR INCREASES TOWARD 18Z AS THE
MID LEVEL WAVE CURRENTLY IN WI ARRIVES IN NW LOWER. THE LIFT
ASSOCIATED WITH THIS FEATURE SHOULD TRIGGER STORMS. THE SHEAR WILL
HELP TO INCREASE THE POTENTIAL FOR ORGANIZED CONVECTION AND
RESULTING SEVERE WEATHER. DAMAGING WINDS AND LARGE HAIL A THREAT.
SRH VALUES AROUND 200 M2/S2 DO SUPPORT A RISK FOR TORNADOES.

.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 322 PM EDT SUN AUG 31 2014

MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT INTO NEXT WEEKEND...
HOWEVER THERE ARE TIMING DIFFERENCES WITH A STRONG COLD FRONT THAT
COMES THROUGH FRIDAY/FRIDAY NIGHT.

LARGE HIGH PRESSURE IS EXPECTED TO BE SITTING OVER THE EAST SEABOARD
BY MID WEEK.  THIS WILL BRING WARMING SOUTHERLY FLOW TO THE GREAT
LAKES REGION.  IT CONTINUES TO LOOK LIKE THURSDAY WILL BE THE
WARMEST DAY OF THE WEEK WITH 80S FOR HIGHS.  THE RISK FOR SHOWERS
AND STORMS WILL INCREASE ON THURSDAY WITH A COLD FRONT MOVING INTO
THE WESTERN GREAT LAKES. WARM AND MOIST AIR WITH MOVE IN AHEAD OF
THIS FRONT.  IF A LOW LEVEL JET COMES INTO PLAY WE COULD BE LOOKING
AT STRONG TO SEVERE STORMS TOWARD THE END OF THE DAY.

THERE CONTINUES TO BE TIMING DIFFERENCES WITH THE FRONT...BUT THE
GFS SLOWED THE FRONT DOWN...CLOSER TO THE WHAT THE ECMWF HAS SHOWN.
THEREFORE BELIEVE THE FRONT WILL BE COMING THROUGH ON FRIDAY WITH
ADDITIONAL CHANCES FOR SHOWERS AND STORMS.  MUCH COOLER AIR FOLLOWS
THIS STRONG FRONT FOR FRIDAY NIGHT AND INTO NEXT WEEKEND.  H8 TEMPS
DROP TO +7 TO +10C AS COMPARED TO AROUND +19C AHEAD OF THE COLD
FRONT.  THE WEEKEND SHOULD FEATURE HIGHS IN THE UPPER 60S TO MID 70S
WITH MAINLY DRY WEATHER.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 149 AM EDT MON SEP 1 2014

THERE ARE A FEW ITEMS THAT COULD IMPACT AVIATION OPERATIONS OVER
THE NEXT 24 HOURS ACROSS SW LOWER MI. THE FIRST ITEM IS FOG
POTENTIAL. A DECENT AMOUNT OF LOW LEVEL MOISTURE REMAINS IN
PLACE THIS MORNING AND TEMPS AND DEW POINTS ARE CLOSE ALREADY. THE
BEST CHC FOR FOG AND SOME POSSIBLE STRATUS WILL BE ALONG AND SE OF
I-69 WHERE A FEW SHOWERS WERE PRESENT EARLIER AND WHERE THE
MOISTURE HAS HUNG IN THE MOST. CAN NOT RULE OUT SOME NEAR KGRR AND
KAZO...BUT THE FURTHER WEST THE WINDS WILL REMAIN UP AND LIMIT FOG POTENTIAL.

THE NEXT THING IS THE POTENTIAL FOR PCPN TODAY. MOST DATA
INDICATES THAT WHATEVER IS LEFT OF THE LINE OF SHOWERS/STORMS NEAR
THE MISSISSIPPI RIVER AS OF 0545Z WILL MOVE INTO THE AREA
TOWARD 15Z OR SO. IT WILL INITIALLY FALL APART WITH LESS CHC OF
IMPACTS FROM IT TOWARD THE LAKESHORE. AS IT ENCOUNTERS SOME
DIURNAL INSTABILITY TOWARD THE EAST...WE EXPECT IT TO REINTENSIFY
INTO A LINE OF STORMS BY THE TIME IT REACHES U.S.-127 BY 19Z OR
SO. BEST CHC FOR LOWER CONDITIONS WILL BE ACROSS THE EAST WHERE
IFR WOULD BE LIKELY IN HEAVY RAINFALL. THIS CAN BE FINE TUNED
CLOSER TO THE EVENT.

ONCE THE LINE OF STORMS MOVES EAST...THERE SHOULD BE SOMEWHAT OF A
BREAK. ANOTHER PERIOD OF SOME SHOWERS WILL BE POSSIBLE WITH THE
WAVE TOWARD 00Z AND AFTER THAT.

&&

.MARINE...
ISSUED AT 322 PM EDT SUN AUG 31 2014

BEACH HAZARDS AND SCA ISSUED FOR MONDAY


&&

.HYDROLOGY...
ISSUED AT 322 PM EDT SUN AUG 31 2014

HIGH PWAT VALUES SUPPORT LOCALLY HEAVY RAIN ON MONDAY.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM 10 AM EDT THIS MORNING THROUGH THIS
     EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 10 PM EDT THIS
     EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 010549
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
149 AM EDT MON SEP 1 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 322 PM EDT SUN AUG 31 2014

A WEAK AREA OF HIGH PRESSURE WILL KEEP MUCH OF THE REGION DRY INTO
THE EVENING. A COLD FRONT WILL APPROACH FROM THE WEST ON LABOR DAY
TRIGGERING SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL RETURN
FOR TUESDAY DRYING THE REGION OUT.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 322 PM EDT SUN AUG 31 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE POTENTIAL FOR
SEVERE WEATHER ON MONDAY. OVERALL THE POTENTIAL STILL EXISTS.

ONE POTENTIAL LIMITING FACTOR WILL BE WHAT IMPACTS THE DECAYING
AREA OF THUNDERSTORMS WILL HAVE AS IT MOVES IN FROM THE WEST
MONDAY MORNING. THE HRRR RUC SHOWS THIS SYSTEM WEAKENING WELL
BEFORE IT ARRIVES IN MI...SO I AM THINKING THIS WILL HAVE A
MINIMAL IMPACT ON THE POTENTIAL INSTABILITY MONDAY. THE
COMBINATION OF HEATING AND MOISTURE ADVECTION SUPPORTS CAPE OVER
1500 J/KG ON MONDAY. DEEP LAYER SHEAR INCREASES TOWARD 18Z AS THE
MID LEVEL WAVE CURRENTLY IN WI ARRIVES IN NW LOWER. THE LIFT
ASSOCIATED WITH THIS FEATURE SHOULD TRIGGER STORMS. THE SHEAR WILL
HELP TO INCREASE THE POTENTIAL FOR ORGANIZED CONVECTION AND
RESULTING SEVERE WEATHER. DAMAGING WINDS AND LARGE HAIL A THREAT.
SRH VALUES AROUND 200 M2/S2 DO SUPPORT A RISK FOR TORNADOES.

.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 322 PM EDT SUN AUG 31 2014

MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT INTO NEXT WEEKEND...
HOWEVER THERE ARE TIMING DIFFERENCES WITH A STRONG COLD FRONT THAT
COMES THROUGH FRIDAY/FRIDAY NIGHT.

LARGE HIGH PRESSURE IS EXPECTED TO BE SITTING OVER THE EAST SEABOARD
BY MID WEEK.  THIS WILL BRING WARMING SOUTHERLY FLOW TO THE GREAT
LAKES REGION.  IT CONTINUES TO LOOK LIKE THURSDAY WILL BE THE
WARMEST DAY OF THE WEEK WITH 80S FOR HIGHS.  THE RISK FOR SHOWERS
AND STORMS WILL INCREASE ON THURSDAY WITH A COLD FRONT MOVING INTO
THE WESTERN GREAT LAKES. WARM AND MOIST AIR WITH MOVE IN AHEAD OF
THIS FRONT.  IF A LOW LEVEL JET COMES INTO PLAY WE COULD BE LOOKING
AT STRONG TO SEVERE STORMS TOWARD THE END OF THE DAY.

THERE CONTINUES TO BE TIMING DIFFERENCES WITH THE FRONT...BUT THE
GFS SLOWED THE FRONT DOWN...CLOSER TO THE WHAT THE ECMWF HAS SHOWN.
THEREFORE BELIEVE THE FRONT WILL BE COMING THROUGH ON FRIDAY WITH
ADDITIONAL CHANCES FOR SHOWERS AND STORMS.  MUCH COOLER AIR FOLLOWS
THIS STRONG FRONT FOR FRIDAY NIGHT AND INTO NEXT WEEKEND.  H8 TEMPS
DROP TO +7 TO +10C AS COMPARED TO AROUND +19C AHEAD OF THE COLD
FRONT.  THE WEEKEND SHOULD FEATURE HIGHS IN THE UPPER 60S TO MID 70S
WITH MAINLY DRY WEATHER.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 149 AM EDT MON SEP 1 2014

THERE ARE A FEW ITEMS THAT COULD IMPACT AVIATION OPERATIONS OVER
THE NEXT 24 HOURS ACROSS SW LOWER MI. THE FIRST ITEM IS FOG
POTENTIAL. A DECENT AMOUNT OF LOW LEVEL MOISTURE REMAINS IN
PLACE THIS MORNING AND TEMPS AND DEW POINTS ARE CLOSE ALREADY. THE
BEST CHC FOR FOG AND SOME POSSIBLE STRATUS WILL BE ALONG AND SE OF
I-69 WHERE A FEW SHOWERS WERE PRESENT EARLIER AND WHERE THE
MOISTURE HAS HUNG IN THE MOST. CAN NOT RULE OUT SOME NEAR KGRR AND
KAZO...BUT THE FURTHER WEST THE WINDS WILL REMAIN UP AND LIMIT FOG POTENTIAL.

THE NEXT THING IS THE POTENTIAL FOR PCPN TODAY. MOST DATA
INDICATES THAT WHATEVER IS LEFT OF THE LINE OF SHOWERS/STORMS NEAR
THE MISSISSIPPI RIVER AS OF 0545Z WILL MOVE INTO THE AREA
TOWARD 15Z OR SO. IT WILL INITIALLY FALL APART WITH LESS CHC OF
IMPACTS FROM IT TOWARD THE LAKESHORE. AS IT ENCOUNTERS SOME
DIURNAL INSTABILITY TOWARD THE EAST...WE EXPECT IT TO REINTENSIFY
INTO A LINE OF STORMS BY THE TIME IT REACHES U.S.-127 BY 19Z OR
SO. BEST CHC FOR LOWER CONDITIONS WILL BE ACROSS THE EAST WHERE
IFR WOULD BE LIKELY IN HEAVY RAINFALL. THIS CAN BE FINE TUNED
CLOSER TO THE EVENT.

ONCE THE LINE OF STORMS MOVES EAST...THERE SHOULD BE SOMEWHAT OF A
BREAK. ANOTHER PERIOD OF SOME SHOWERS WILL BE POSSIBLE WITH THE
WAVE TOWARD 00Z AND AFTER THAT.

&&

.MARINE...
ISSUED AT 322 PM EDT SUN AUG 31 2014

BEACH HAZARDS AND SCA ISSUED FOR MONDAY


&&

.HYDROLOGY...
ISSUED AT 322 PM EDT SUN AUG 31 2014

HIGH PWAT VALUES SUPPORT LOCALLY HEAVY RAIN ON MONDAY.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM 10 AM EDT THIS MORNING THROUGH THIS
     EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 10 PM EDT THIS
     EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 312242
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
645 PM EDT SUN AUG 31 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 322 PM EDT SUN AUG 31 2014

A WEAK AREA OF HIGH PRESSURE WILL KEEP MUCH OF THE REGION DRY INTO
THE EVENING. A COLD FRONT WILL APPROACH FROM THE WEST ON LABOR DAY
TRIGGERING SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL RETURN
FOR TUESDAY DRYING THE REGION OUT.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 322 PM EDT SUN AUG 31 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE POTENTIAL FOR
SEVERE WEATHER ON MONDAY. OVERALL THE POTENTIAL STILL EXISTS.

ONE POTENTIAL LIMITING FACTOR WILL BE WHAT IMPACTS THE DECAYING
AREA OF THUNDERSTORMS WILL HAVE AS IT MOVES IN FROM THE WEST
MONDAY MORNING. THE HRRR RUC SHOWS THIS SYSTEM WEAKENING WELL
BEFORE IT ARRIVES IN MI...SO I AM THINKING THIS WILL HAVE A
MINIMAL IMPACT ON THE POTENTIAL INSTABILITY MONDAY. THE
COMBINATION OF HEATING AND MOISTURE ADVECTION SUPPORTS CAPE OVER
1500 J/KG ON MONDAY. DEEP LAYER SHEAR INCREASES TOWARD 18Z AS THE
MID LEVEL WAVE CURRENTLY IN WI ARRIVES IN NW LOWER. THE LIFT
ASSOCIATED WITH THIS FEATURE SHOULD TRIGGER STORMS. THE SHEAR WILL
HELP TO INCREASE THE POTENTIAL FOR ORGANIZED CONVECTION AND
RESULTING SEVERE WEATHER. DAMAGING WINDS AND LARGE HAIL A THREAT.
SRH VALUES AROUND 200 M2/S2 DO SUPPORT A RISK FOR TORNADOES.

&&

.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 322 PM EDT SUN AUG 31 2014

MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT INTO NEXT WEEKEND...
HOWEVER THERE ARE TIMING DIFFERENCES WITH A STRONG COLD FRONT THAT
COMES THROUGH FRIDAY/FRIDAY NIGHT.

LARGE HIGH PRESSURE IS EXPECTED TO BE SITTING OVER THE EAST SEABOARD
BY MID WEEK.  THIS WILL BRING WARMING SOUTHERLY FLOW TO THE GREAT
LAKES REGION.  IT CONTINUES TO LOOK LIKE THURSDAY WILL BE THE
WARMEST DAY OF THE WEEK WITH 80S FOR HIGHS.  THE RISK FOR SHOWERS
AND STORMS WILL INCREASE ON THURSDAY WITH A COLD FRONT MOVING INTO
THE WESTERN GREAT LAKES. WARM AND MOIST AIR WITH MOVE IN AHEAD OF
THIS FRONT.  IF A LOW LEVEL JET COMES INTO PLAY WE COULD BE LOOKING
AT STRONG TO SEVERE STORMS TOWARD THE END OF THE DAY.

THERE CONTINUES TO BE TIMING DIFFERENCES WITH THE FRONT...BUT THE
GFS SLOWED THE FRONT DOWN...CLOSER TO THE WHAT THE ECMWF HAS SHOWN.
THEREFORE BELIEVE THE FRONT WILL BE COMING THROUGH ON FRIDAY WITH
ADDITIONAL CHANCES FOR SHOWERS AND STORMS.  MUCH COOLER AIR FOLLOWS
THIS STRONG FRONT FOR FRIDAY NIGHT AND INTO NEXT WEEKEND.  H8 TEMPS
DROP TO +7 TO +10C AS COMPARED TO AROUND +19C AHEAD OF THE COLD
FRONT.  THE WEEKEND SHOULD FEATURE HIGHS IN THE UPPER 60S TO MID 70S
WITH MAINLY DRY WEATHER.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 645 PM EDT SUN AUG 31 2014

SCATTERED SHOWERS MAY AFFECT OUR SOUTHEAST TERMINALS (KLAN AND
PERHAPS KBTL/KJXN) DURING THE EARLY TO MID EVENING HOURS TONIGHT
BEFORE DISSIPATING. MAINLY VFR CONDITIONS ARE ANTICIPATED OVERNIGHT
BUT SOME PATCHY MVFR CONDITIONS MAY DEVELOP DURING THE EARLY MORNING
HOURS MONDAY DUE TO LOW CLOUDS AND/OR FOG. CONDITIONS SHOULD THEN
GRADUALLY DETERIORATE TO MAINLY MVFR MONDAY MORNING DUE TO LOW
CLOUDS AND PATCHY FOG.

BY LATE MONDAY MORNING/EARLY AFTERNOON SSW WINDS WILL INCREASE WITH
GUSTS AROUND 20 TO 25 KTS. SCATTERED THUNDERSTORMS WILL ALSO DEVELOP
FROM LATE MONDAY MORNING THROUGH MONDAY AFTERNOON AS INSTABILITY
INCREASES AHEAD OF AN APPROACHING COLD FRONT. SCATTERED SHOWERS AND
THUNDERSTORMS WILL LINGER MONDAY EVENING.

&&

.MARINE...
ISSUED AT 322 PM EDT SUN AUG 31 2014

BEACH HAZARDS AND SCA ISSUED FOR MONDAY

&&

.HYDROLOGY...
ISSUED AT 322 PM EDT SUN AUG 31 2014

HIGH PWAT VALUES SUPPORT LOCALLY HEAVY RAIN ON MONDAY.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM MONDAY MORNING THROUGH MONDAY
     EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY FROM 10 AM TO 10 PM EDT MONDAY FOR
     LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...LAURENS
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 312242
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
645 PM EDT SUN AUG 31 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 322 PM EDT SUN AUG 31 2014

A WEAK AREA OF HIGH PRESSURE WILL KEEP MUCH OF THE REGION DRY INTO
THE EVENING. A COLD FRONT WILL APPROACH FROM THE WEST ON LABOR DAY
TRIGGERING SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL RETURN
FOR TUESDAY DRYING THE REGION OUT.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 322 PM EDT SUN AUG 31 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE POTENTIAL FOR
SEVERE WEATHER ON MONDAY. OVERALL THE POTENTIAL STILL EXISTS.

ONE POTENTIAL LIMITING FACTOR WILL BE WHAT IMPACTS THE DECAYING
AREA OF THUNDERSTORMS WILL HAVE AS IT MOVES IN FROM THE WEST
MONDAY MORNING. THE HRRR RUC SHOWS THIS SYSTEM WEAKENING WELL
BEFORE IT ARRIVES IN MI...SO I AM THINKING THIS WILL HAVE A
MINIMAL IMPACT ON THE POTENTIAL INSTABILITY MONDAY. THE
COMBINATION OF HEATING AND MOISTURE ADVECTION SUPPORTS CAPE OVER
1500 J/KG ON MONDAY. DEEP LAYER SHEAR INCREASES TOWARD 18Z AS THE
MID LEVEL WAVE CURRENTLY IN WI ARRIVES IN NW LOWER. THE LIFT
ASSOCIATED WITH THIS FEATURE SHOULD TRIGGER STORMS. THE SHEAR WILL
HELP TO INCREASE THE POTENTIAL FOR ORGANIZED CONVECTION AND
RESULTING SEVERE WEATHER. DAMAGING WINDS AND LARGE HAIL A THREAT.
SRH VALUES AROUND 200 M2/S2 DO SUPPORT A RISK FOR TORNADOES.

&&

.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 322 PM EDT SUN AUG 31 2014

MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT INTO NEXT WEEKEND...
HOWEVER THERE ARE TIMING DIFFERENCES WITH A STRONG COLD FRONT THAT
COMES THROUGH FRIDAY/FRIDAY NIGHT.

LARGE HIGH PRESSURE IS EXPECTED TO BE SITTING OVER THE EAST SEABOARD
BY MID WEEK.  THIS WILL BRING WARMING SOUTHERLY FLOW TO THE GREAT
LAKES REGION.  IT CONTINUES TO LOOK LIKE THURSDAY WILL BE THE
WARMEST DAY OF THE WEEK WITH 80S FOR HIGHS.  THE RISK FOR SHOWERS
AND STORMS WILL INCREASE ON THURSDAY WITH A COLD FRONT MOVING INTO
THE WESTERN GREAT LAKES. WARM AND MOIST AIR WITH MOVE IN AHEAD OF
THIS FRONT.  IF A LOW LEVEL JET COMES INTO PLAY WE COULD BE LOOKING
AT STRONG TO SEVERE STORMS TOWARD THE END OF THE DAY.

THERE CONTINUES TO BE TIMING DIFFERENCES WITH THE FRONT...BUT THE
GFS SLOWED THE FRONT DOWN...CLOSER TO THE WHAT THE ECMWF HAS SHOWN.
THEREFORE BELIEVE THE FRONT WILL BE COMING THROUGH ON FRIDAY WITH
ADDITIONAL CHANCES FOR SHOWERS AND STORMS.  MUCH COOLER AIR FOLLOWS
THIS STRONG FRONT FOR FRIDAY NIGHT AND INTO NEXT WEEKEND.  H8 TEMPS
DROP TO +7 TO +10C AS COMPARED TO AROUND +19C AHEAD OF THE COLD
FRONT.  THE WEEKEND SHOULD FEATURE HIGHS IN THE UPPER 60S TO MID 70S
WITH MAINLY DRY WEATHER.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 645 PM EDT SUN AUG 31 2014

SCATTERED SHOWERS MAY AFFECT OUR SOUTHEAST TERMINALS (KLAN AND
PERHAPS KBTL/KJXN) DURING THE EARLY TO MID EVENING HOURS TONIGHT
BEFORE DISSIPATING. MAINLY VFR CONDITIONS ARE ANTICIPATED OVERNIGHT
BUT SOME PATCHY MVFR CONDITIONS MAY DEVELOP DURING THE EARLY MORNING
HOURS MONDAY DUE TO LOW CLOUDS AND/OR FOG. CONDITIONS SHOULD THEN
GRADUALLY DETERIORATE TO MAINLY MVFR MONDAY MORNING DUE TO LOW
CLOUDS AND PATCHY FOG.

BY LATE MONDAY MORNING/EARLY AFTERNOON SSW WINDS WILL INCREASE WITH
GUSTS AROUND 20 TO 25 KTS. SCATTERED THUNDERSTORMS WILL ALSO DEVELOP
FROM LATE MONDAY MORNING THROUGH MONDAY AFTERNOON AS INSTABILITY
INCREASES AHEAD OF AN APPROACHING COLD FRONT. SCATTERED SHOWERS AND
THUNDERSTORMS WILL LINGER MONDAY EVENING.

&&

.MARINE...
ISSUED AT 322 PM EDT SUN AUG 31 2014

BEACH HAZARDS AND SCA ISSUED FOR MONDAY

&&

.HYDROLOGY...
ISSUED AT 322 PM EDT SUN AUG 31 2014

HIGH PWAT VALUES SUPPORT LOCALLY HEAVY RAIN ON MONDAY.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM MONDAY MORNING THROUGH MONDAY
     EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY FROM 10 AM TO 10 PM EDT MONDAY FOR
     LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...LAURENS
HYDROLOGY...MJS
MARINE...MJS









000
FXUS63 KGRR 311930
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
330 PM EDT SUN AUG 31 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE

.SYNOPSIS...
ISSUED AT 322 PM EDT SUN AUG 31 2014

A WEAK AREA OF HIGH PRESSURE WILL KEEP MUCH OF THE REGION DRY INTO
THE EVENING. A COLD FRONT WILL APPROACH FROM THE WEST ON LABOR DAY
TRIGGERING SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL RETURN
FOR TUESDAY DRYING THE REGION OUT.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 322 PM EDT SUN AUG 31 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE POTENTIAL FOR
SEVERE WEATHER ON MONDAY. OVERALL THE POTENTIAL STILL EXISTS.

ONE POTENTIAL LIMITING FACTOR WILL BE WHAT IMPACTS THE DECAYING
AREA OF THUNDERSTORMS WILL HAVE AS IT MOVES IN FROM THE WEST
MONDAY MORNING. THE HRRR RUC SHOWS THIS SYSTEM WEAKENING WELL
BEFORE IT ARRIVES IN MI...SO I AM THINKING THIS WILL HAVE A
MINIMAL IMPACT ON THE POTENTIAL INSTABILITY MONDAY. THE
COMBINATION OF HEATING AND MOISTURE ADVECTION SUPPORTS CAPE OVER
1500 J/KG ON MONDAY. DEEP LAYER SHEAR INCREASES TOWARD 18Z AS THE
MID LEVEL WAVE CURRENTLY IN WI ARRIVES IN NW LOWER. THE LIFT
ASSOCIATED WITH THIS FEATURE SHOULD TRIGGER STORMS. THE SHEAR WILL
HELP TO INCREASE THE POTENTIAL FOR ORGANIZED CONVECTION AND
RESULTING SEVERE WEATHER. DAMAGING WINDS AND LARGE HAIL A THREAT.
SRH VALUES AROUND 200 M2/S2 DO SUPPORT A RISK FOR TORNADOES.





.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 322 PM EDT SUN AUG 31 2014

MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT INTO NEXT WEEKEND...
HOWEVER THERE ARE TIMING DIFFERENCES WITH A STRONG COLD FRONT THAT
COMES THROUGH FRIDAY/FRIDAY NIGHT.

LARGE HIGH PRESSURE IS EXPECTED TO BE SITTING OVER THE EAST SEABOARD
BY MID WEEK.  THIS WILL BRING WARMING SOUTHERLY FLOW TO THE GREAT
LAKES REGION.  IT CONTINUES TO LOOK LIKE THURSDAY WILL BE THE
WARMEST DAY OF THE WEEK WITH 80S FOR HIGHS.  THE RISK FOR SHOWERS
AND STORMS WILL INCREASE ON THURSDAY WITH A COLD FRONT MOVING INTO
THE WESTERN GREAT LAKES. WARM AND MOIST AIR WITH MOVE IN AHEAD OF
THIS FRONT.  IF A LOW LEVEL JET COMES INTO PLAY WE COULD BE LOOKING
AT STRONG TO SEVERE STORMS TOWARD THE END OF THE DAY.

THERE CONTINUES TO BE TIMING DIFFERENCES WITH THE FRONT...BUT THE
GFS SLOWED THE FRONT DOWN...CLOSER TO THE WHAT THE ECMWF HAS SHOWN.
THEREFORE BELIEVE THE FRONT WILL BE COMING THROUGH ON FRIDAY WITH
ADDITIONAL CHANCES FOR SHOWERS AND STORMS.  MUCH COOLER AIR FOLLOWS
THIS STRONG FRONT FOR FRIDAY NIGHT AND INTO NEXT WEEKEND.  H8 TEMPS
DROP TO +7 TO +10C AS COMPARED TO AROUND +19C AHEAD OF THE COLD
FRONT.  THE WEEKEND SHOULD FEATURE HIGHS IN THE UPPER 60S TO MID 70S
WITH MAINLY DRY WEATHER.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 134 PM EDT SUN AUG 31 2014

CEILINGS WERE TRENDING TOWARD VFR EARLY THIS AFTERNOON...HOWEVER
SOME MVFR MAY HOLD ON UNTIL ABOUT 20Z. OTHERWISE THE VFR AND LIGHT
WINDS WILL BE MAINTAINED INTO AND THROUGH MUCH OF THE OVERNIGHT. I
HAVE INTRODUCED SOME MVFR CEILINGS RETURNING AROUND DAYBREAK
MONDAY DUE TO MOIST LOW LEVELS AND DIURNAL TRENDS.

THEN BY LATE MONDAY MORNING/EARLY AFTERNOON SSW WINDS WILL
INCREASE WITH GUSTS AROUND 20 KNOTS. ALSO IN THIS TIME FRAME
WIDELY SCATTERED THUNDERSTORMS MAY BEGIN TO DEVELOP AS INSTABILITY
INCREASES AHEAD OF AN APPROACHING COLD FRONT.


&&

.MARINE...
ISSUED AT 322 PM EDT SUN AUG 31 2014

BEACH HAZARDS AND SCA ISSUED FOR MONDAY

&&

.HYDROLOGY...
ISSUED AT 322 PM EDT SUN AUG 31 2014

HIGH PWAT VALUES SUPPORT LOCALLY HEAVY RAIN ON MONDAY.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM MONDAY MORNING THROUGH MONDAY
     EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY FROM 10 AM TO 10 PM EDT MONDAY FOR
     LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...JK
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 311930
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
330 PM EDT SUN AUG 31 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE

.SYNOPSIS...
ISSUED AT 322 PM EDT SUN AUG 31 2014

A WEAK AREA OF HIGH PRESSURE WILL KEEP MUCH OF THE REGION DRY INTO
THE EVENING. A COLD FRONT WILL APPROACH FROM THE WEST ON LABOR DAY
TRIGGERING SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL RETURN
FOR TUESDAY DRYING THE REGION OUT.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 322 PM EDT SUN AUG 31 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE POTENTIAL FOR
SEVERE WEATHER ON MONDAY. OVERALL THE POTENTIAL STILL EXISTS.

ONE POTENTIAL LIMITING FACTOR WILL BE WHAT IMPACTS THE DECAYING
AREA OF THUNDERSTORMS WILL HAVE AS IT MOVES IN FROM THE WEST
MONDAY MORNING. THE HRRR RUC SHOWS THIS SYSTEM WEAKENING WELL
BEFORE IT ARRIVES IN MI...SO I AM THINKING THIS WILL HAVE A
MINIMAL IMPACT ON THE POTENTIAL INSTABILITY MONDAY. THE
COMBINATION OF HEATING AND MOISTURE ADVECTION SUPPORTS CAPE OVER
1500 J/KG ON MONDAY. DEEP LAYER SHEAR INCREASES TOWARD 18Z AS THE
MID LEVEL WAVE CURRENTLY IN WI ARRIVES IN NW LOWER. THE LIFT
ASSOCIATED WITH THIS FEATURE SHOULD TRIGGER STORMS. THE SHEAR WILL
HELP TO INCREASE THE POTENTIAL FOR ORGANIZED CONVECTION AND
RESULTING SEVERE WEATHER. DAMAGING WINDS AND LARGE HAIL A THREAT.
SRH VALUES AROUND 200 M2/S2 DO SUPPORT A RISK FOR TORNADOES.





.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 322 PM EDT SUN AUG 31 2014

MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT INTO NEXT WEEKEND...
HOWEVER THERE ARE TIMING DIFFERENCES WITH A STRONG COLD FRONT THAT
COMES THROUGH FRIDAY/FRIDAY NIGHT.

LARGE HIGH PRESSURE IS EXPECTED TO BE SITTING OVER THE EAST SEABOARD
BY MID WEEK.  THIS WILL BRING WARMING SOUTHERLY FLOW TO THE GREAT
LAKES REGION.  IT CONTINUES TO LOOK LIKE THURSDAY WILL BE THE
WARMEST DAY OF THE WEEK WITH 80S FOR HIGHS.  THE RISK FOR SHOWERS
AND STORMS WILL INCREASE ON THURSDAY WITH A COLD FRONT MOVING INTO
THE WESTERN GREAT LAKES. WARM AND MOIST AIR WITH MOVE IN AHEAD OF
THIS FRONT.  IF A LOW LEVEL JET COMES INTO PLAY WE COULD BE LOOKING
AT STRONG TO SEVERE STORMS TOWARD THE END OF THE DAY.

THERE CONTINUES TO BE TIMING DIFFERENCES WITH THE FRONT...BUT THE
GFS SLOWED THE FRONT DOWN...CLOSER TO THE WHAT THE ECMWF HAS SHOWN.
THEREFORE BELIEVE THE FRONT WILL BE COMING THROUGH ON FRIDAY WITH
ADDITIONAL CHANCES FOR SHOWERS AND STORMS.  MUCH COOLER AIR FOLLOWS
THIS STRONG FRONT FOR FRIDAY NIGHT AND INTO NEXT WEEKEND.  H8 TEMPS
DROP TO +7 TO +10C AS COMPARED TO AROUND +19C AHEAD OF THE COLD
FRONT.  THE WEEKEND SHOULD FEATURE HIGHS IN THE UPPER 60S TO MID 70S
WITH MAINLY DRY WEATHER.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 134 PM EDT SUN AUG 31 2014

CEILINGS WERE TRENDING TOWARD VFR EARLY THIS AFTERNOON...HOWEVER
SOME MVFR MAY HOLD ON UNTIL ABOUT 20Z. OTHERWISE THE VFR AND LIGHT
WINDS WILL BE MAINTAINED INTO AND THROUGH MUCH OF THE OVERNIGHT. I
HAVE INTRODUCED SOME MVFR CEILINGS RETURNING AROUND DAYBREAK
MONDAY DUE TO MOIST LOW LEVELS AND DIURNAL TRENDS.

THEN BY LATE MONDAY MORNING/EARLY AFTERNOON SSW WINDS WILL
INCREASE WITH GUSTS AROUND 20 KNOTS. ALSO IN THIS TIME FRAME
WIDELY SCATTERED THUNDERSTORMS MAY BEGIN TO DEVELOP AS INSTABILITY
INCREASES AHEAD OF AN APPROACHING COLD FRONT.


&&

.MARINE...
ISSUED AT 322 PM EDT SUN AUG 31 2014

BEACH HAZARDS AND SCA ISSUED FOR MONDAY

&&

.HYDROLOGY...
ISSUED AT 322 PM EDT SUN AUG 31 2014

HIGH PWAT VALUES SUPPORT LOCALLY HEAVY RAIN ON MONDAY.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM MONDAY MORNING THROUGH MONDAY
     EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY FROM 10 AM TO 10 PM EDT MONDAY FOR
     LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...JK
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 311734
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
134 PM EDT SUN AUG 31 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 328 AM EDT SUN AUG 31 2014

HIGH PRESSURE WILL MOVE ACROSS LOWER MICHIGAN TODAY. THIS SHOULD
RESULT IN AT LEAST PARTIAL SUNSHINE ACROSS THE AREA THIS AFTERNOON.
AN ISOLATED THUNDERSTORMS IS POSSIBLE EAST OF US-131 AND SOUTH OF
I-96 DURING THE EARLY TO MID AFTERNOON. EXPECT MOSTLY CLEAR SKIES
TONIGHT WITH LOWS MOSTLY IN THE 60S. A COLD FRONT MOVING INTO THE
AREA BY LATE MONDAY NIGHT WILL RESULT IN THUNDERSTORMS MONDAY
AFTERNOON INTO MONDAY EVENING. SOME OF THESE STORMS COULD BE
STRONG TO SEVERE. TEMPERATURES WILL WARM WITH HIGHS IN THE 80S.
COOLER AND DRIER WEATHER FOLLOWS THE COLD FRONT FOR TUESDAY INTO
WEDNESDAY.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

WE CONTINUE TO TRACK THE POTENTIAL FOR SEVERE STORMS MONDAY
AFTERNOON INTO MONDAY EVENING. OTHERWISE TRANQUIL WEATHER IS
EXPECTED TODAY INTO TONIGHT.

AN UNSEASONABLY STRONG PACIFIC SYSTEM WILL BRING THE POLAR JET
STREAM UNUSUALLY FAR SOUTH FOR EARLY SEPTEMBER (1 IN 10 YEAR RETURN
PERIOD FOR EARLY SEPTEMBER) ON MONDAY. A COUPLE JET FEATURE WILL
HELP FOCUS THUNDERSTORMS SUNDAY NIGHT INTO EARLY MONDAY OVER
MINNESOTA AND WISCONSIN. THIS STRONG UPPER LEVEL JET WILL RESULT
IN A 35 TO 45 KNOT LOW LEVEL JET THAT WILL TRACK ACROSS SOUTHERN
WISCONSIN EARLY MONDAY MORNING THEN LIFT NORTHEAST WILL THE
COUPLED JET CORE INTO UPPER MICHIGAN MONDAY AFTERNOON. THE 1000 TO
850 MOISTURE TRANSPORT VECTORS CONVERGE OVER EASTERN WISCONSIN
DURING THE EARLY TO MID MORNING HOURS OF MONDAY BUT THAT
FEATURE... LIKE THE LOW LEVEL JET ALSO LIFTS NORTHEAST INTO UPPER
MICHIGAN AND EASTERN LAKE SUPERIOR BY EARLY MONDAY AFTERNOON.
MEANWHILE THERE SHOULD BE AT LEAST 1500 J/KG OF MIXED LAYER CAPE
OVER CENTRAL AND EASTERN LOWER MICH GAIN BY EARLY MONDAY
AFTERNOON AND THERE WILL BE 30 TO 40 KNOTS OF DEEP LAYER SHEAR
MONDAY AFTERNOON OVER ALL OF LOWER MICHIGAN. ALL OF THIS WOULD
SUGGEST AT LEAST SOME POTENTIAL FOR A LINE OF THUNDERSTORMS
CROSSING LOWER MICHIGAN DURING THE LATE MORNING INTO MID AFTERNOON.
SOUNDINGS FROM THE GFS SUGGEST THE EQUILIBRIUM LEVEL WILL BE NEAR
THE TROP AND THERE IS A SIGNIFICANT AMOUNT OF CAPE IN THE -10 TO
-30 RANGE SO HAIL WOULD BE POSSIBLE AS WELL AS GUSTY WINDS.

SO...WILL THERE BE SEVERE STORMS OVER SOUTHWEST LOWER MICHIGAN ON
LABOR DAY?  ALL OF THIS SUGGEST SEVERE STORMS ARE SURELY POSSIBLE.
WE ARE IN SLIGHT RISK FROM THE SPC DAY 2 OUTLOOK. HOWEVER THERE
ARE SOME QUESTIONS. FIRST SOUTHWEST MICHIGAN IS IN THE SPEED
DIVERGENCE AREA OF THE LOW LEVEL JET MONDAY AFTERNOON. THAT IS NOT
THE PLACE YOU WOULD WANT TO BE TO GET CONCENTRATED SEVERE STORM
ACTIVITY. ALSO SOUTHWEST MICHIGAN IS IN THE RIGHT FRONT EXIT
REGION OF THE JET WHICH IS ACTUALLY OVER WISCONSIN YET MONDAY
AFTERNOON. THIS IS ALSO NOT CONDUCIVE TO SEVERE STORMS. ANTHER
NEGATIVE IS THE LINE OF STORMS COMING OUT OF WISCONSIN DURING THE
MID MORNING HOURS OF MONDAY. THAT WILL BRING LAYERED CLOUDS ACROSS
THE AREA CUTTING BACK ON SURFACE HEATING. YET GIVEN ALL OF THE
ABOVE THERE STILL AT LEAST A SLIGHT RISK AS SPC INDICATES. WE WILL
HAVE TO WATCH HOW THE CONVECTION ACTUALLY PLAYS OUT MONDAY MORNING
BEFORE WE HAVE A BETTER IDEA OF HOW GREAT THE SEVERE RISK HERE IS
ON LABOR DAY.

THE ENTRANCE REGION OF THAT SAME POLAR JET CORE COMES ACROSS
MICHIGAN EARLY TUESDAY. THAT WILL EDUCE A WAVE ON THE FRONT AND
MAY BRING CONVECTION BACK NORTH INTO SOUTHERN LOWER MICHIGAN
DURING THE EARLY MORNING HOURS OF TUESDAY. WE WILL HAVE TO WATCH
THIS CLOSELY. THESE COULD BE STRONG STORMS TOO IF THE GET THIS FAR
NORTH. ONCE THAT IS THROUGH QUIET WEATHER RETURNS BY TUESDAY
AFTERNOON.

.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

THE LONG TERM PORTION OF THE FCST WILL FEATURE QUIET WEATHER FOR A
GOOD MAJORITY OF THE PERIOD. A FLAT UPPER RIDGE WILL BUILD IN BY TUE
NIGHT IN THE WAKE OF THE EARLY WEEK SYSTEM. WE WILL SEE SFC RIDGING
TAKE CONTROL OF THE WEATHER FOR WED AND MOSTLY THU KEEPING MOST OF
THE AREA DRY. AS SRLY FLOW INCREASES ON THU...WE WILL SEE QUITE WARM
TEMPS MOVE IN. THE AREA SHOULD BE WELL INTO THE 80S BY THU WITH H850
TEMPS INCREASING TO THE UPPER TEENS C. THIS COULD BE A BIT
CONSERVATIVE FOR MAX TEMPS.

THE ONLY UNSETTLED PERIOD LOOKS TO BE DURING THE LATE THU THROUGH
EARLY SAT TIME FRAME. WE WILL SEE OUR FLAT UPPER RIDGE BE PUSHED OUT
BY AN UPPER TROUGH EXPECTED TO EXTEND FROM CENTRAL CANADA TO THE NRN
ROCKIES ON THU. THIS UPPER TROUGH WILL PUSH A COLD FRONT INTO THE
AREA CENTERED ON THE DAY ON FRI RIGHT NOW. THIS FRONT SHOULD MOVE
INTO A FAIR AMOUNT OF INSTABILITY...HELPING TO PRODUCE SHOWERS AND
STORMS.

THIS FRONT SHOULD CLEAR THE AREA BY SAT MORNING....ALLOWING COOLER
AND DRIER AIR TO FILTER BACK INTO THE AREA FROM THE NORTH.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 134 PM EDT SUN AUG 31 2014

CEILINGS WERE TRENDING TOWARD VFR EARLY THIS AFTERNOON...HOWEVER
SOME MVFR MAY HOLD ON UNTIL ABOUT 20Z. OTHERWISE THE VFR AND LIGHT
WINDS WILL BE MAINTAINED INTO AND THROUGH MUCH OF THE OVERNIGHT. I
HAVE INTRODUCED SOME MVFR CEILINGS RETURNING AROUND DAYBREAK
MONDAY DUE TO MOIST LOW LEVELS AND DIURNAL TRENDS.

THEN BY LATE MONDAY MORNING/EARLY AFTERNOON SSW WINDS WILL
INCREASE WITH GUSTS AROUND 20 KNOTS. ALSO IN THIS TIME FRAME
WIDELY SCATTERED THUNDERSTORMS MAY BEGIN TO DEVELOP AS INSTABILITY
INCREASES AHEAD OF AN APPROACHING COLD FRONT.

&&

.MARINE...
ISSUED AT 1159 AM EDT SUN AUG 31 2014

THE FORECAST FOR THIS AFTERNOON AND EVENING STILL LOOKS LIKE WAVES
GENERALLY UNDER 2 FEET GIVEN THE WEAKER WINDS FORECASTED. HIGHER
CONFIDENCE ON THE NEED FOR A SCA AND BEACH HAZARDS FOR MONDAY.
INCOMING MODEL DATA SUPPORTS THIS. WILL LIKELY ISSUE STATEMENTS
THIS AFTERNOON.


&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...JK
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 311734
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
134 PM EDT SUN AUG 31 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 328 AM EDT SUN AUG 31 2014

HIGH PRESSURE WILL MOVE ACROSS LOWER MICHIGAN TODAY. THIS SHOULD
RESULT IN AT LEAST PARTIAL SUNSHINE ACROSS THE AREA THIS AFTERNOON.
AN ISOLATED THUNDERSTORMS IS POSSIBLE EAST OF US-131 AND SOUTH OF
I-96 DURING THE EARLY TO MID AFTERNOON. EXPECT MOSTLY CLEAR SKIES
TONIGHT WITH LOWS MOSTLY IN THE 60S. A COLD FRONT MOVING INTO THE
AREA BY LATE MONDAY NIGHT WILL RESULT IN THUNDERSTORMS MONDAY
AFTERNOON INTO MONDAY EVENING. SOME OF THESE STORMS COULD BE
STRONG TO SEVERE. TEMPERATURES WILL WARM WITH HIGHS IN THE 80S.
COOLER AND DRIER WEATHER FOLLOWS THE COLD FRONT FOR TUESDAY INTO
WEDNESDAY.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

WE CONTINUE TO TRACK THE POTENTIAL FOR SEVERE STORMS MONDAY
AFTERNOON INTO MONDAY EVENING. OTHERWISE TRANQUIL WEATHER IS
EXPECTED TODAY INTO TONIGHT.

AN UNSEASONABLY STRONG PACIFIC SYSTEM WILL BRING THE POLAR JET
STREAM UNUSUALLY FAR SOUTH FOR EARLY SEPTEMBER (1 IN 10 YEAR RETURN
PERIOD FOR EARLY SEPTEMBER) ON MONDAY. A COUPLE JET FEATURE WILL
HELP FOCUS THUNDERSTORMS SUNDAY NIGHT INTO EARLY MONDAY OVER
MINNESOTA AND WISCONSIN. THIS STRONG UPPER LEVEL JET WILL RESULT
IN A 35 TO 45 KNOT LOW LEVEL JET THAT WILL TRACK ACROSS SOUTHERN
WISCONSIN EARLY MONDAY MORNING THEN LIFT NORTHEAST WILL THE
COUPLED JET CORE INTO UPPER MICHIGAN MONDAY AFTERNOON. THE 1000 TO
850 MOISTURE TRANSPORT VECTORS CONVERGE OVER EASTERN WISCONSIN
DURING THE EARLY TO MID MORNING HOURS OF MONDAY BUT THAT
FEATURE... LIKE THE LOW LEVEL JET ALSO LIFTS NORTHEAST INTO UPPER
MICHIGAN AND EASTERN LAKE SUPERIOR BY EARLY MONDAY AFTERNOON.
MEANWHILE THERE SHOULD BE AT LEAST 1500 J/KG OF MIXED LAYER CAPE
OVER CENTRAL AND EASTERN LOWER MICH GAIN BY EARLY MONDAY
AFTERNOON AND THERE WILL BE 30 TO 40 KNOTS OF DEEP LAYER SHEAR
MONDAY AFTERNOON OVER ALL OF LOWER MICHIGAN. ALL OF THIS WOULD
SUGGEST AT LEAST SOME POTENTIAL FOR A LINE OF THUNDERSTORMS
CROSSING LOWER MICHIGAN DURING THE LATE MORNING INTO MID AFTERNOON.
SOUNDINGS FROM THE GFS SUGGEST THE EQUILIBRIUM LEVEL WILL BE NEAR
THE TROP AND THERE IS A SIGNIFICANT AMOUNT OF CAPE IN THE -10 TO
-30 RANGE SO HAIL WOULD BE POSSIBLE AS WELL AS GUSTY WINDS.

SO...WILL THERE BE SEVERE STORMS OVER SOUTHWEST LOWER MICHIGAN ON
LABOR DAY?  ALL OF THIS SUGGEST SEVERE STORMS ARE SURELY POSSIBLE.
WE ARE IN SLIGHT RISK FROM THE SPC DAY 2 OUTLOOK. HOWEVER THERE
ARE SOME QUESTIONS. FIRST SOUTHWEST MICHIGAN IS IN THE SPEED
DIVERGENCE AREA OF THE LOW LEVEL JET MONDAY AFTERNOON. THAT IS NOT
THE PLACE YOU WOULD WANT TO BE TO GET CONCENTRATED SEVERE STORM
ACTIVITY. ALSO SOUTHWEST MICHIGAN IS IN THE RIGHT FRONT EXIT
REGION OF THE JET WHICH IS ACTUALLY OVER WISCONSIN YET MONDAY
AFTERNOON. THIS IS ALSO NOT CONDUCIVE TO SEVERE STORMS. ANTHER
NEGATIVE IS THE LINE OF STORMS COMING OUT OF WISCONSIN DURING THE
MID MORNING HOURS OF MONDAY. THAT WILL BRING LAYERED CLOUDS ACROSS
THE AREA CUTTING BACK ON SURFACE HEATING. YET GIVEN ALL OF THE
ABOVE THERE STILL AT LEAST A SLIGHT RISK AS SPC INDICATES. WE WILL
HAVE TO WATCH HOW THE CONVECTION ACTUALLY PLAYS OUT MONDAY MORNING
BEFORE WE HAVE A BETTER IDEA OF HOW GREAT THE SEVERE RISK HERE IS
ON LABOR DAY.

THE ENTRANCE REGION OF THAT SAME POLAR JET CORE COMES ACROSS
MICHIGAN EARLY TUESDAY. THAT WILL EDUCE A WAVE ON THE FRONT AND
MAY BRING CONVECTION BACK NORTH INTO SOUTHERN LOWER MICHIGAN
DURING THE EARLY MORNING HOURS OF TUESDAY. WE WILL HAVE TO WATCH
THIS CLOSELY. THESE COULD BE STRONG STORMS TOO IF THE GET THIS FAR
NORTH. ONCE THAT IS THROUGH QUIET WEATHER RETURNS BY TUESDAY
AFTERNOON.

.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

THE LONG TERM PORTION OF THE FCST WILL FEATURE QUIET WEATHER FOR A
GOOD MAJORITY OF THE PERIOD. A FLAT UPPER RIDGE WILL BUILD IN BY TUE
NIGHT IN THE WAKE OF THE EARLY WEEK SYSTEM. WE WILL SEE SFC RIDGING
TAKE CONTROL OF THE WEATHER FOR WED AND MOSTLY THU KEEPING MOST OF
THE AREA DRY. AS SRLY FLOW INCREASES ON THU...WE WILL SEE QUITE WARM
TEMPS MOVE IN. THE AREA SHOULD BE WELL INTO THE 80S BY THU WITH H850
TEMPS INCREASING TO THE UPPER TEENS C. THIS COULD BE A BIT
CONSERVATIVE FOR MAX TEMPS.

THE ONLY UNSETTLED PERIOD LOOKS TO BE DURING THE LATE THU THROUGH
EARLY SAT TIME FRAME. WE WILL SEE OUR FLAT UPPER RIDGE BE PUSHED OUT
BY AN UPPER TROUGH EXPECTED TO EXTEND FROM CENTRAL CANADA TO THE NRN
ROCKIES ON THU. THIS UPPER TROUGH WILL PUSH A COLD FRONT INTO THE
AREA CENTERED ON THE DAY ON FRI RIGHT NOW. THIS FRONT SHOULD MOVE
INTO A FAIR AMOUNT OF INSTABILITY...HELPING TO PRODUCE SHOWERS AND
STORMS.

THIS FRONT SHOULD CLEAR THE AREA BY SAT MORNING....ALLOWING COOLER
AND DRIER AIR TO FILTER BACK INTO THE AREA FROM THE NORTH.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 134 PM EDT SUN AUG 31 2014

CEILINGS WERE TRENDING TOWARD VFR EARLY THIS AFTERNOON...HOWEVER
SOME MVFR MAY HOLD ON UNTIL ABOUT 20Z. OTHERWISE THE VFR AND LIGHT
WINDS WILL BE MAINTAINED INTO AND THROUGH MUCH OF THE OVERNIGHT. I
HAVE INTRODUCED SOME MVFR CEILINGS RETURNING AROUND DAYBREAK
MONDAY DUE TO MOIST LOW LEVELS AND DIURNAL TRENDS.

THEN BY LATE MONDAY MORNING/EARLY AFTERNOON SSW WINDS WILL
INCREASE WITH GUSTS AROUND 20 KNOTS. ALSO IN THIS TIME FRAME
WIDELY SCATTERED THUNDERSTORMS MAY BEGIN TO DEVELOP AS INSTABILITY
INCREASES AHEAD OF AN APPROACHING COLD FRONT.

&&

.MARINE...
ISSUED AT 1159 AM EDT SUN AUG 31 2014

THE FORECAST FOR THIS AFTERNOON AND EVENING STILL LOOKS LIKE WAVES
GENERALLY UNDER 2 FEET GIVEN THE WEAKER WINDS FORECASTED. HIGHER
CONFIDENCE ON THE NEED FOR A SCA AND BEACH HAZARDS FOR MONDAY.
INCOMING MODEL DATA SUPPORTS THIS. WILL LIKELY ISSUE STATEMENTS
THIS AFTERNOON.


&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...JK
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 311600
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1200 PM EDT SUN AUG 31 2014

LATEST UPDATE...
MARINE

.SYNOPSIS...
ISSUED AT 328 AM EDT SUN AUG 31 2014

HIGH PRESSURE WILL MOVE ACROSS LOWER MICHIGAN TODAY. THIS SHOULD
RESULT IN AT LEAST PARTIAL SUNSHINE ACROSS THE AREA THIS AFTERNOON.
AN ISOLATED THUNDERSTORMS IS POSSIBLE EAST OF US-131 AND SOUTH OF
I-96 DURING THE EARLY TO MID AFTERNOON. EXPECT MOSTLY CLEAR SKIES
TONIGHT WITH LOWS MOSTLY IN THE 60S. A COLD FRONT MOVING INTO THE
AREA BY LATE MONDAY NIGHT WILL RESULT IN THUNDERSTORMS MONDAY
AFTERNOON INTO MONDAY EVENING. SOME OF THESE STORMS COULD BE
STRONG TO SEVERE. TEMPERATURES WILL WARM WITH HIGHS IN THE 80S.
COOLER AND DRIER WEATHER FOLLOWS THE COLD FRONT FOR TUESDAY INTO
WEDNESDAY.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

WE CONTINUE TO TRACK THE POTENTIAL FOR SEVERE STORMS MONDAY
AFTERNOON INTO MONDAY EVENING. OTHERWISE TRANQUIL WEATHER IS
EXPECTED TODAY INTO TONIGHT.

AN UNSEASONABLY STRONG PACIFIC SYSTEM WILL BRING THE POLAR JET
STREAM UNUSUALLY FAR SOUTH FOR EARLY SEPTEMBER (1 IN 10 YEAR RETURN
PERIOD FOR EARLY SEPTEMBER) ON MONDAY. A COUPLE JET FEATURE WILL
HELP FOCUS THUNDERSTORMS SUNDAY NIGHT INTO EARLY MONDAY OVER
MINNESOTA AND WISCONSIN. THIS STRONG UPPER LEVEL JET WILL RESULT
IN A 35 TO 45 KNOT LOW LEVEL JET THAT WILL TRACK ACROSS SOUTHERN
WISCONSIN EARLY MONDAY MORNING THEN LIFT NORTHEAST WILL THE
COUPLED JET CORE INTO UPPER MICHIGAN MONDAY AFTERNOON. THE 1000 TO
850 MOISTURE TRANSPORT VECTORS CONVERGE OVER EASTERN WISCONSIN
DURING THE EARLY TO MID MORNING HOURS OF MONDAY BUT THAT
FEATURE... LIKE THE LOW LEVEL JET ALSO LIFTS NORTHEAST INTO UPPER
MICHIGAN AND EASTERN LAKE SUPERIOR BY EARLY MONDAY AFTERNOON.
MEANWHILE THERE SHOULD BE AT LEAST 1500 J/KG OF MIXED LAYER CAPE
OVER CENTRAL AND EASTERN LOWER MICH GAIN BY EARLY MONDAY
AFTERNOON AND THERE WILL BE 30 TO 40 KNOTS OF DEEP LAYER SHEAR
MONDAY AFTERNOON OVER ALL OF LOWER MICHIGAN. ALL OF THIS WOULD
SUGGEST AT LEAST SOME POTENTIAL FOR A LINE OF THUNDERSTORMS
CROSSING LOWER MICHIGAN DURING THE LATE MORNING INTO MID AFTERNOON.
SOUNDINGS FROM THE GFS SUGGEST THE EQUILIBRIUM LEVEL WILL BE NEAR
THE TROP AND THERE IS A SIGNIFICANT AMOUNT OF CAPE IN THE -10 TO
-30 RANGE SO HAIL WOULD BE POSSIBLE AS WELL AS GUSTY WINDS.

SO...WILL THERE BE SEVERE STORMS OVER SOUTHWEST LOWER MICHIGAN ON
LABOR DAY?  ALL OF THIS SUGGEST SEVERE STORMS ARE SURELY POSSIBLE.
WE ARE IN SLIGHT RISK FROM THE SPC DAY 2 OUTLOOK. HOWEVER THERE
ARE SOME QUESTIONS. FIRST SOUTHWEST MICHIGAN IS IN THE SPEED
DIVERGENCE AREA OF THE LOW LEVEL JET MONDAY AFTERNOON. THAT IS NOT
THE PLACE YOU WOULD WANT TO BE TO GET CONCENTRATED SEVERE STORM
ACTIVITY. ALSO SOUTHWEST MICHIGAN IS IN THE RIGHT FRONT EXIT
REGION OF THE JET WHICH IS ACTUALLY OVER WISCONSIN YET MONDAY
AFTERNOON. THIS IS ALSO NOT CONDUCIVE TO SEVERE STORMS. ANTHER
NEGATIVE IS THE LINE OF STORMS COMING OUT OF WISCONSIN DURING THE
MID MORNING HOURS OF MONDAY. THAT WILL BRING LAYERED CLOUDS ACROSS
THE AREA CUTTING BACK ON SURFACE HEATING. YET GIVEN ALL OF THE
ABOVE THERE STILL AT LEAST A SLIGHT RISK AS SPC INDICATES. WE WILL
HAVE TO WATCH HOW THE CONVECTION ACTUALLY PLAYS OUT MONDAY MORNING
BEFORE WE HAVE A BETTER IDEA OF HOW GREAT THE SEVERE RISK HERE IS
ON LABOR DAY.

THE ENTRANCE REGION OF THAT SAME POLAR JET CORE COMES ACROSS
MICHIGAN EARLY TUESDAY. THAT WILL EDUCE A WAVE ON THE FRONT AND
MAY BRING CONVECTION BACK NORTH INTO SOUTHERN LOWER MICHIGAN
DURING THE EARLY MORNING HOURS OF TUESDAY. WE WILL HAVE TO WATCH
THIS CLOSELY. THESE COULD BE STRONG STORMS TOO IF THE GET THIS FAR
NORTH. ONCE THAT IS THROUGH QUIET WEATHER RETURNS BY TUESDAY
AFTERNOON.

.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

THE LONG TERM PORTION OF THE FCST WILL FEATURE QUIET WEATHER FOR A
GOOD MAJORITY OF THE PERIOD. A FLAT UPPER RIDGE WILL BUILD IN BY TUE
NIGHT IN THE WAKE OF THE EARLY WEEK SYSTEM. WE WILL SEE SFC RIDGING
TAKE CONTROL OF THE WEATHER FOR WED AND MOSTLY THU KEEPING MOST OF
THE AREA DRY. AS SRLY FLOW INCREASES ON THU...WE WILL SEE QUITE WARM
TEMPS MOVE IN. THE AREA SHOULD BE WELL INTO THE 80S BY THU WITH H850
TEMPS INCREASING TO THE UPPER TEENS C. THIS COULD BE A BIT
CONSERVATIVE FOR MAX TEMPS.

THE ONLY UNSETTLED PERIOD LOOKS TO BE DURING THE LATE THU THROUGH
EARLY SAT TIME FRAME. WE WILL SEE OUR FLAT UPPER RIDGE BE PUSHED OUT
BY AN UPPER TROUGH EXPECTED TO EXTEND FROM CENTRAL CANADA TO THE NRN
ROCKIES ON THU. THIS UPPER TROUGH WILL PUSH A COLD FRONT INTO THE
AREA CENTERED ON THE DAY ON FRI RIGHT NOW. THIS FRONT SHOULD MOVE
INTO A FAIR AMOUNT OF INSTABILITY...HELPING TO PRODUCE SHOWERS AND
STORMS.

THIS FRONT SHOULD CLEAR THE AREA BY SAT MORNING....ALLOWING COOLER
AND DRIER AIR TO FILTER BACK INTO THE AREA FROM THE NORTH.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 724 AM EDT SUN AUG 31 2014

CURRENTLY (11Z) THERE IS A BAND OF IFR CIGS WITH MVFR VISIBILITIES
THROUGH KGRR AND KLAN WHILE KMKG...KAZO AND KBTL ARE VFR. HOWEVER
IR SATELLITE LOOPS THE CLOUDS ARE NOT FAR AWAY FROM THOSE OTHER
SITES. I BELIEVE ALL OF THE TAF SITES WILL HAVE IFR CIGS FOR
SEVERAL HOURS THIS MORNING BEFORE THIS ALL MIXES OUT BY EARLY
AFTERNOON.

THERE IS ENOUGH INSTABILITY FOR SHOWERS TO REDEVELOP THIS
AFTERNOON. HOWEVER... THE ONLY LOCATIONS WHERE THERE IS ENOUGH
SURFACE CONVERGENCE FOR THOSE SHOWERS TO BE FORCED IS FOR THE
I-94 TAF SITES. THAT IS WHERE THE FRONT WILL BE STALLED THIS
AFTERNOON. SO I CONTINUED THE IDEA OF VCSH FOR THOSE TAF SITES.
ACTUALLY A THUNDERSTORM WOULD NOT BE OUT OF THE QUESTION FOR THOSE
TAF SITES.

SKIES SHOULD CLEAR ACROSS THE AREA TONIGHT. THERE SHOULD BE ENOUGH
WIND IN THE BOUNDARY LAYER TO KEEP VFR GOING THROUGH THE NIGHT.


&&

.MARINE...
ISSUED AT 1159 AM EDT SUN AUG 31 2014

THE FORECAST FOR THIS AFTERNOON AND EVENING STILL LOOKS LIKE WAVES
GENERALLY UNDER 2 FEET GIVEN THE WEAKER WINDS FORECASTED. HIGHER
CONFIDENCE ON THE NEED FOR A SCA AND BEACH HAZARDS FOR MONDAY.
INCOMING MODEL DATA SUPPORTS THIS. WILL LIKELY ISSUE STATEMENTS
THIS AFTERNOON.

&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 311600
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1200 PM EDT SUN AUG 31 2014

LATEST UPDATE...
MARINE

.SYNOPSIS...
ISSUED AT 328 AM EDT SUN AUG 31 2014

HIGH PRESSURE WILL MOVE ACROSS LOWER MICHIGAN TODAY. THIS SHOULD
RESULT IN AT LEAST PARTIAL SUNSHINE ACROSS THE AREA THIS AFTERNOON.
AN ISOLATED THUNDERSTORMS IS POSSIBLE EAST OF US-131 AND SOUTH OF
I-96 DURING THE EARLY TO MID AFTERNOON. EXPECT MOSTLY CLEAR SKIES
TONIGHT WITH LOWS MOSTLY IN THE 60S. A COLD FRONT MOVING INTO THE
AREA BY LATE MONDAY NIGHT WILL RESULT IN THUNDERSTORMS MONDAY
AFTERNOON INTO MONDAY EVENING. SOME OF THESE STORMS COULD BE
STRONG TO SEVERE. TEMPERATURES WILL WARM WITH HIGHS IN THE 80S.
COOLER AND DRIER WEATHER FOLLOWS THE COLD FRONT FOR TUESDAY INTO
WEDNESDAY.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

WE CONTINUE TO TRACK THE POTENTIAL FOR SEVERE STORMS MONDAY
AFTERNOON INTO MONDAY EVENING. OTHERWISE TRANQUIL WEATHER IS
EXPECTED TODAY INTO TONIGHT.

AN UNSEASONABLY STRONG PACIFIC SYSTEM WILL BRING THE POLAR JET
STREAM UNUSUALLY FAR SOUTH FOR EARLY SEPTEMBER (1 IN 10 YEAR RETURN
PERIOD FOR EARLY SEPTEMBER) ON MONDAY. A COUPLE JET FEATURE WILL
HELP FOCUS THUNDERSTORMS SUNDAY NIGHT INTO EARLY MONDAY OVER
MINNESOTA AND WISCONSIN. THIS STRONG UPPER LEVEL JET WILL RESULT
IN A 35 TO 45 KNOT LOW LEVEL JET THAT WILL TRACK ACROSS SOUTHERN
WISCONSIN EARLY MONDAY MORNING THEN LIFT NORTHEAST WILL THE
COUPLED JET CORE INTO UPPER MICHIGAN MONDAY AFTERNOON. THE 1000 TO
850 MOISTURE TRANSPORT VECTORS CONVERGE OVER EASTERN WISCONSIN
DURING THE EARLY TO MID MORNING HOURS OF MONDAY BUT THAT
FEATURE... LIKE THE LOW LEVEL JET ALSO LIFTS NORTHEAST INTO UPPER
MICHIGAN AND EASTERN LAKE SUPERIOR BY EARLY MONDAY AFTERNOON.
MEANWHILE THERE SHOULD BE AT LEAST 1500 J/KG OF MIXED LAYER CAPE
OVER CENTRAL AND EASTERN LOWER MICH GAIN BY EARLY MONDAY
AFTERNOON AND THERE WILL BE 30 TO 40 KNOTS OF DEEP LAYER SHEAR
MONDAY AFTERNOON OVER ALL OF LOWER MICHIGAN. ALL OF THIS WOULD
SUGGEST AT LEAST SOME POTENTIAL FOR A LINE OF THUNDERSTORMS
CROSSING LOWER MICHIGAN DURING THE LATE MORNING INTO MID AFTERNOON.
SOUNDINGS FROM THE GFS SUGGEST THE EQUILIBRIUM LEVEL WILL BE NEAR
THE TROP AND THERE IS A SIGNIFICANT AMOUNT OF CAPE IN THE -10 TO
-30 RANGE SO HAIL WOULD BE POSSIBLE AS WELL AS GUSTY WINDS.

SO...WILL THERE BE SEVERE STORMS OVER SOUTHWEST LOWER MICHIGAN ON
LABOR DAY?  ALL OF THIS SUGGEST SEVERE STORMS ARE SURELY POSSIBLE.
WE ARE IN SLIGHT RISK FROM THE SPC DAY 2 OUTLOOK. HOWEVER THERE
ARE SOME QUESTIONS. FIRST SOUTHWEST MICHIGAN IS IN THE SPEED
DIVERGENCE AREA OF THE LOW LEVEL JET MONDAY AFTERNOON. THAT IS NOT
THE PLACE YOU WOULD WANT TO BE TO GET CONCENTRATED SEVERE STORM
ACTIVITY. ALSO SOUTHWEST MICHIGAN IS IN THE RIGHT FRONT EXIT
REGION OF THE JET WHICH IS ACTUALLY OVER WISCONSIN YET MONDAY
AFTERNOON. THIS IS ALSO NOT CONDUCIVE TO SEVERE STORMS. ANTHER
NEGATIVE IS THE LINE OF STORMS COMING OUT OF WISCONSIN DURING THE
MID MORNING HOURS OF MONDAY. THAT WILL BRING LAYERED CLOUDS ACROSS
THE AREA CUTTING BACK ON SURFACE HEATING. YET GIVEN ALL OF THE
ABOVE THERE STILL AT LEAST A SLIGHT RISK AS SPC INDICATES. WE WILL
HAVE TO WATCH HOW THE CONVECTION ACTUALLY PLAYS OUT MONDAY MORNING
BEFORE WE HAVE A BETTER IDEA OF HOW GREAT THE SEVERE RISK HERE IS
ON LABOR DAY.

THE ENTRANCE REGION OF THAT SAME POLAR JET CORE COMES ACROSS
MICHIGAN EARLY TUESDAY. THAT WILL EDUCE A WAVE ON THE FRONT AND
MAY BRING CONVECTION BACK NORTH INTO SOUTHERN LOWER MICHIGAN
DURING THE EARLY MORNING HOURS OF TUESDAY. WE WILL HAVE TO WATCH
THIS CLOSELY. THESE COULD BE STRONG STORMS TOO IF THE GET THIS FAR
NORTH. ONCE THAT IS THROUGH QUIET WEATHER RETURNS BY TUESDAY
AFTERNOON.

.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

THE LONG TERM PORTION OF THE FCST WILL FEATURE QUIET WEATHER FOR A
GOOD MAJORITY OF THE PERIOD. A FLAT UPPER RIDGE WILL BUILD IN BY TUE
NIGHT IN THE WAKE OF THE EARLY WEEK SYSTEM. WE WILL SEE SFC RIDGING
TAKE CONTROL OF THE WEATHER FOR WED AND MOSTLY THU KEEPING MOST OF
THE AREA DRY. AS SRLY FLOW INCREASES ON THU...WE WILL SEE QUITE WARM
TEMPS MOVE IN. THE AREA SHOULD BE WELL INTO THE 80S BY THU WITH H850
TEMPS INCREASING TO THE UPPER TEENS C. THIS COULD BE A BIT
CONSERVATIVE FOR MAX TEMPS.

THE ONLY UNSETTLED PERIOD LOOKS TO BE DURING THE LATE THU THROUGH
EARLY SAT TIME FRAME. WE WILL SEE OUR FLAT UPPER RIDGE BE PUSHED OUT
BY AN UPPER TROUGH EXPECTED TO EXTEND FROM CENTRAL CANADA TO THE NRN
ROCKIES ON THU. THIS UPPER TROUGH WILL PUSH A COLD FRONT INTO THE
AREA CENTERED ON THE DAY ON FRI RIGHT NOW. THIS FRONT SHOULD MOVE
INTO A FAIR AMOUNT OF INSTABILITY...HELPING TO PRODUCE SHOWERS AND
STORMS.

THIS FRONT SHOULD CLEAR THE AREA BY SAT MORNING....ALLOWING COOLER
AND DRIER AIR TO FILTER BACK INTO THE AREA FROM THE NORTH.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 724 AM EDT SUN AUG 31 2014

CURRENTLY (11Z) THERE IS A BAND OF IFR CIGS WITH MVFR VISIBILITIES
THROUGH KGRR AND KLAN WHILE KMKG...KAZO AND KBTL ARE VFR. HOWEVER
IR SATELLITE LOOPS THE CLOUDS ARE NOT FAR AWAY FROM THOSE OTHER
SITES. I BELIEVE ALL OF THE TAF SITES WILL HAVE IFR CIGS FOR
SEVERAL HOURS THIS MORNING BEFORE THIS ALL MIXES OUT BY EARLY
AFTERNOON.

THERE IS ENOUGH INSTABILITY FOR SHOWERS TO REDEVELOP THIS
AFTERNOON. HOWEVER... THE ONLY LOCATIONS WHERE THERE IS ENOUGH
SURFACE CONVERGENCE FOR THOSE SHOWERS TO BE FORCED IS FOR THE
I-94 TAF SITES. THAT IS WHERE THE FRONT WILL BE STALLED THIS
AFTERNOON. SO I CONTINUED THE IDEA OF VCSH FOR THOSE TAF SITES.
ACTUALLY A THUNDERSTORM WOULD NOT BE OUT OF THE QUESTION FOR THOSE
TAF SITES.

SKIES SHOULD CLEAR ACROSS THE AREA TONIGHT. THERE SHOULD BE ENOUGH
WIND IN THE BOUNDARY LAYER TO KEEP VFR GOING THROUGH THE NIGHT.


&&

.MARINE...
ISSUED AT 1159 AM EDT SUN AUG 31 2014

THE FORECAST FOR THIS AFTERNOON AND EVENING STILL LOOKS LIKE WAVES
GENERALLY UNDER 2 FEET GIVEN THE WEAKER WINDS FORECASTED. HIGHER
CONFIDENCE ON THE NEED FOR A SCA AND BEACH HAZARDS FOR MONDAY.
INCOMING MODEL DATA SUPPORTS THIS. WILL LIKELY ISSUE STATEMENTS
THIS AFTERNOON.

&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 311124
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
724 AM EDT SUN AUG 31 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 328 AM EDT SUN AUG 31 2014

HIGH PRESSURE WILL MOVE ACROSS LOWER MICHIGAN TODAY. THIS SHOULD
RESULT IN AT LEAST PARTIAL SUNSHINE ACROSS THE AREA THIS AFTERNOON.
AN ISOLATED THUNDERSTORMS IS POSSIBLE EAST OF US-131 AND SOUTH OF
I-96 DURING THE EARLY TO MID AFTERNOON. EXPECT MOSTLY CLEAR SKIES
TONIGHT WITH LOWS MOSTLY IN THE 60S. A COLD FRONT MOVING INTO THE
AREA BY LATE MONDAY NIGHT WILL RESULT IN THUNDERSTORMS MONDAY
AFTERNOON INTO MONDAY EVENING. SOME OF THESE STORMS COULD BE
STRONG TO SEVERE. TEMPERATURES WILL WARM WITH HIGHS IN THE 80S.
COOLER AND DRIER WEATHER FOLLOWS THE COLD FRONT FOR TUESDAY INTO
WEDNESDAY.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

WE CONTINUE TO TRACK THE POTENTIAL FOR SEVERE STORMS MONDAY
AFTERNOON INTO MONDAY EVENING. OTHERWISE TRANQUIL WEATHER IS
EXPECTED TODAY INTO TONIGHT.

AN UNSEASONABLY STRONG PACIFIC SYSTEM WILL BRING THE POLAR JET
STREAM UNUSUALLY FAR SOUTH FOR EARLY SEPTEMBER (1 IN 10 YEAR RETURN
PERIOD FOR EARLY SEPTEMBER) ON MONDAY. A COUPLE JET FEATURE WILL
HELP FOCUS THUNDERSTORMS SUNDAY NIGHT INTO EARLY MONDAY OVER
MINNESOTA AND WISCONSIN. THIS STRONG UPPER LEVEL JET WILL RESULT
IN A 35 TO 45 KNOT LOW LEVEL JET THAT WILL TRACK ACROSS SOUTHERN
WISCONSIN EARLY MONDAY MORNING THEN LIFT NORTHEAST WILL THE
COUPLED JET CORE INTO UPPER MICHIGAN MONDAY AFTERNOON. THE 1000 TO
850 MOISTURE TRANSPORT VECTORS CONVERGE OVER EASTERN WISCONSIN
DURING THE EARLY TO MID MORNING HOURS OF MONDAY BUT THAT
FEATURE... LIKE THE LOW LEVEL JET ALSO LIFTS NORTHEAST INTO UPPER
MICHIGAN AND EASTERN LAKE SUPERIOR BY EARLY MONDAY AFTERNOON.
MEANWHILE THERE SHOULD BE AT LEAST 1500 J/KG OF MIXED LAYER CAPE
OVER CENTRAL AND EASTERN LOWER MICH GAIN BY EARLY MONDAY
AFTERNOON AND THERE WILL BE 30 TO 40 KNOTS OF DEEP LAYER SHEAR
MONDAY AFTERNOON OVER ALL OF LOWER MICHIGAN. ALL OF THIS WOULD
SUGGEST AT LEAST SOME POTENTIAL FOR A LINE OF THUNDERSTORMS
CROSSING LOWER MICHIGAN DURING THE LATE MORNING INTO MID AFTERNOON.
SOUNDINGS FROM THE GFS SUGGEST THE EQUILIBRIUM LEVEL WILL BE NEAR
THE TROP AND THERE IS A SIGNIFICANT AMOUNT OF CAPE IN THE -10 TO
-30 RANGE SO HAIL WOULD BE POSSIBLE AS WELL AS GUSTY WINDS.

SO...WILL THERE BE SEVERE STORMS OVER SOUTHWEST LOWER MICHIGAN ON
LABOR DAY?  ALL OF THIS SUGGEST SEVERE STORMS ARE SURELY POSSIBLE.
WE ARE IN SLIGHT RISK FROM THE SPC DAY 2 OUTLOOK. HOWEVER THERE
ARE SOME QUESTIONS. FIRST SOUTHWEST MICHIGAN IS IN THE SPEED
DIVERGENCE AREA OF THE LOW LEVEL JET MONDAY AFTERNOON. THAT IS NOT
THE PLACE YOU WOULD WANT TO BE TO GET CONCENTRATED SEVERE STORM
ACTIVITY. ALSO SOUTHWEST MICHIGAN IS IN THE RIGHT FRONT EXIT
REGION OF THE JET WHICH IS ACTUALLY OVER WISCONSIN YET MONDAY
AFTERNOON. THIS IS ALSO NOT CONDUCIVE TO SEVERE STORMS. ANTHER
NEGATIVE IS THE LINE OF STORMS COMING OUT OF WISCONSIN DURING THE
MID MORNING HOURS OF MONDAY. THAT WILL BRING LAYERED CLOUDS ACROSS
THE AREA CUTTING BACK ON SURFACE HEATING. YET GIVEN ALL OF THE
ABOVE THERE STILL AT LEAST A SLIGHT RISK AS SPC INDICATES. WE WILL
HAVE TO WATCH HOW THE CONVECTION ACTUALLY PLAYS OUT MONDAY MORNING
BEFORE WE HAVE A BETTER IDEA OF HOW GREAT THE SEVERE RISK HERE IS
ON LABOR DAY.

THE ENTRANCE REGION OF THAT SAME POLAR JET CORE COMES ACROSS
MICHIGAN EARLY TUESDAY. THAT WILL EDUCE A WAVE ON THE FRONT AND
MAY BRING CONVECTION BACK NORTH INTO SOUTHERN LOWER MICHIGAN
DURING THE EARLY MORNING HOURS OF TUESDAY. WE WILL HAVE TO WATCH
THIS CLOSELY. THESE COULD BE STRONG STORMS TOO IF THE GET THIS FAR
NORTH. ONCE THAT IS THROUGH QUIET WEATHER RETURNS BY TUESDAY
AFTERNOON.

.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

THE LONG TERM PORTION OF THE FCST WILL FEATURE QUIET WEATHER FOR A
GOOD MAJORITY OF THE PERIOD. A FLAT UPPER RIDGE WILL BUILD IN BY TUE
NIGHT IN THE WAKE OF THE EARLY WEEK SYSTEM. WE WILL SEE SFC RIDGING
TAKE CONTROL OF THE WEATHER FOR WED AND MOSTLY THU KEEPING MOST OF
THE AREA DRY. AS SRLY FLOW INCREASES ON THU...WE WILL SEE QUITE WARM
TEMPS MOVE IN. THE AREA SHOULD BE WELL INTO THE 80S BY THU WITH H850
TEMPS INCREASING TO THE UPPER TEENS C. THIS COULD BE A BIT
CONSERVATIVE FOR MAX TEMPS.

THE ONLY UNSETTLED PERIOD LOOKS TO BE DURING THE LATE THU THROUGH
EARLY SAT TIME FRAME. WE WILL SEE OUR FLAT UPPER RIDGE BE PUSHED OUT
BY AN UPPER TROUGH EXPECTED TO EXTEND FROM CENTRAL CANADA TO THE NRN
ROCKIES ON THU. THIS UPPER TROUGH WILL PUSH A COLD FRONT INTO THE
AREA CENTERED ON THE DAY ON FRI RIGHT NOW. THIS FRONT SHOULD MOVE
INTO A FAIR AMOUNT OF INSTABILITY...HELPING TO PRODUCE SHOWERS AND
STORMS.

THIS FRONT SHOULD CLEAR THE AREA BY SAT MORNING....ALLOWING COOLER
AND DRIER AIR TO FILTER BACK INTO THE AREA FROM THE NORTH.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 724 AM EDT SUN AUG 31 2014

CURRENTLY (11Z) THERE IS A BAND OF IFR CIGS WITH MVFR VISIBILITIES
THROUGH KGRR AND KLAN WHILE KMKG...KAZO AND KBTL ARE VFR. HOWEVER
IR SATELLITE LOOPS THE CLOUDS ARE NOT FAR AWAY FROM THOSE OTHER
SITES. I BELIEVE ALL OF THE TAF SITES WILL HAVE IFR CIGS FOR
SEVERAL HOURS THIS MORNING BEFORE THIS ALL MIXES OUT BY EARLY
AFTERNOON.

THERE IS ENOUGH INSTABILITY FOR SHOWERS TO REDEVELOP THIS
AFTERNOON. HOWEVER... THE ONLY LOCATIONS WHERE THERE IS ENOUGH
SURFACE CONVERGENCE FOR THOSE SHOWERS TO BE FORCED IS FOR THE
I-94 TAF SITES. THAT IS WHERE THE FRONT WILL BE STALLED THIS
AFTERNOON. SO I CONTINUED THE IDEA OF VCSH FOR THOSE TAF SITES.
ACTUALLY A THUNDERSTORM WOULD NOT BE OUT OF THE QUESTION FOR THOSE
TAF SITES.

SKIES SHOULD CLEAR ACROSS THE AREA TONIGHT. THERE SHOULD BE ENOUGH
WIND IN THE BOUNDARY LAYER TO KEEP VFR GOING THROUGH THE NIGHT.

&&

.MARINE...
ISSUED AT 328 AM EDT SUN AUG 31 2014

NO CONCERNS IN THE FIRST 18 HRS OR SO FOR THE NEARSHORE WATERS WITH
LIGHT WINDS EXPECTED. CONDITIONS ARE LOOKING LIKELY FOR ANOTHER
SMALL CRAFT
ADVISORY/BEACH HAZARDS EVENT FOR THE DAY ON MONDAY.

HIGH PRESSURE BUILDING IN ACROSS THE AREA TODAY WILL KEEP THE
GRADIENT LIGHT AND WINDS AT OR BELOW 10 KNOTS FOR THE MOST PART.
WINDS WILL START INCREASING TONIGHT AND COULD BE FLIRTING WITH SMALL
CRAFT ADVISORY CRITERIA JUST AFTER DAYBREAK ON MONDAY AHEAD OF THE
NEXT FRONT. WINDS AND WAVES LOOK LIKE THEY COULD BE A LITTLE
STRONGER/HIGHER COMPARED TO THE PAST EVENT YESTERDAY.


&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...MJS
MARINE...NJJ








000
FXUS63 KGRR 311124
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
724 AM EDT SUN AUG 31 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 328 AM EDT SUN AUG 31 2014

HIGH PRESSURE WILL MOVE ACROSS LOWER MICHIGAN TODAY. THIS SHOULD
RESULT IN AT LEAST PARTIAL SUNSHINE ACROSS THE AREA THIS AFTERNOON.
AN ISOLATED THUNDERSTORMS IS POSSIBLE EAST OF US-131 AND SOUTH OF
I-96 DURING THE EARLY TO MID AFTERNOON. EXPECT MOSTLY CLEAR SKIES
TONIGHT WITH LOWS MOSTLY IN THE 60S. A COLD FRONT MOVING INTO THE
AREA BY LATE MONDAY NIGHT WILL RESULT IN THUNDERSTORMS MONDAY
AFTERNOON INTO MONDAY EVENING. SOME OF THESE STORMS COULD BE
STRONG TO SEVERE. TEMPERATURES WILL WARM WITH HIGHS IN THE 80S.
COOLER AND DRIER WEATHER FOLLOWS THE COLD FRONT FOR TUESDAY INTO
WEDNESDAY.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

WE CONTINUE TO TRACK THE POTENTIAL FOR SEVERE STORMS MONDAY
AFTERNOON INTO MONDAY EVENING. OTHERWISE TRANQUIL WEATHER IS
EXPECTED TODAY INTO TONIGHT.

AN UNSEASONABLY STRONG PACIFIC SYSTEM WILL BRING THE POLAR JET
STREAM UNUSUALLY FAR SOUTH FOR EARLY SEPTEMBER (1 IN 10 YEAR RETURN
PERIOD FOR EARLY SEPTEMBER) ON MONDAY. A COUPLE JET FEATURE WILL
HELP FOCUS THUNDERSTORMS SUNDAY NIGHT INTO EARLY MONDAY OVER
MINNESOTA AND WISCONSIN. THIS STRONG UPPER LEVEL JET WILL RESULT
IN A 35 TO 45 KNOT LOW LEVEL JET THAT WILL TRACK ACROSS SOUTHERN
WISCONSIN EARLY MONDAY MORNING THEN LIFT NORTHEAST WILL THE
COUPLED JET CORE INTO UPPER MICHIGAN MONDAY AFTERNOON. THE 1000 TO
850 MOISTURE TRANSPORT VECTORS CONVERGE OVER EASTERN WISCONSIN
DURING THE EARLY TO MID MORNING HOURS OF MONDAY BUT THAT
FEATURE... LIKE THE LOW LEVEL JET ALSO LIFTS NORTHEAST INTO UPPER
MICHIGAN AND EASTERN LAKE SUPERIOR BY EARLY MONDAY AFTERNOON.
MEANWHILE THERE SHOULD BE AT LEAST 1500 J/KG OF MIXED LAYER CAPE
OVER CENTRAL AND EASTERN LOWER MICH GAIN BY EARLY MONDAY
AFTERNOON AND THERE WILL BE 30 TO 40 KNOTS OF DEEP LAYER SHEAR
MONDAY AFTERNOON OVER ALL OF LOWER MICHIGAN. ALL OF THIS WOULD
SUGGEST AT LEAST SOME POTENTIAL FOR A LINE OF THUNDERSTORMS
CROSSING LOWER MICHIGAN DURING THE LATE MORNING INTO MID AFTERNOON.
SOUNDINGS FROM THE GFS SUGGEST THE EQUILIBRIUM LEVEL WILL BE NEAR
THE TROP AND THERE IS A SIGNIFICANT AMOUNT OF CAPE IN THE -10 TO
-30 RANGE SO HAIL WOULD BE POSSIBLE AS WELL AS GUSTY WINDS.

SO...WILL THERE BE SEVERE STORMS OVER SOUTHWEST LOWER MICHIGAN ON
LABOR DAY?  ALL OF THIS SUGGEST SEVERE STORMS ARE SURELY POSSIBLE.
WE ARE IN SLIGHT RISK FROM THE SPC DAY 2 OUTLOOK. HOWEVER THERE
ARE SOME QUESTIONS. FIRST SOUTHWEST MICHIGAN IS IN THE SPEED
DIVERGENCE AREA OF THE LOW LEVEL JET MONDAY AFTERNOON. THAT IS NOT
THE PLACE YOU WOULD WANT TO BE TO GET CONCENTRATED SEVERE STORM
ACTIVITY. ALSO SOUTHWEST MICHIGAN IS IN THE RIGHT FRONT EXIT
REGION OF THE JET WHICH IS ACTUALLY OVER WISCONSIN YET MONDAY
AFTERNOON. THIS IS ALSO NOT CONDUCIVE TO SEVERE STORMS. ANTHER
NEGATIVE IS THE LINE OF STORMS COMING OUT OF WISCONSIN DURING THE
MID MORNING HOURS OF MONDAY. THAT WILL BRING LAYERED CLOUDS ACROSS
THE AREA CUTTING BACK ON SURFACE HEATING. YET GIVEN ALL OF THE
ABOVE THERE STILL AT LEAST A SLIGHT RISK AS SPC INDICATES. WE WILL
HAVE TO WATCH HOW THE CONVECTION ACTUALLY PLAYS OUT MONDAY MORNING
BEFORE WE HAVE A BETTER IDEA OF HOW GREAT THE SEVERE RISK HERE IS
ON LABOR DAY.

THE ENTRANCE REGION OF THAT SAME POLAR JET CORE COMES ACROSS
MICHIGAN EARLY TUESDAY. THAT WILL EDUCE A WAVE ON THE FRONT AND
MAY BRING CONVECTION BACK NORTH INTO SOUTHERN LOWER MICHIGAN
DURING THE EARLY MORNING HOURS OF TUESDAY. WE WILL HAVE TO WATCH
THIS CLOSELY. THESE COULD BE STRONG STORMS TOO IF THE GET THIS FAR
NORTH. ONCE THAT IS THROUGH QUIET WEATHER RETURNS BY TUESDAY
AFTERNOON.

.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

THE LONG TERM PORTION OF THE FCST WILL FEATURE QUIET WEATHER FOR A
GOOD MAJORITY OF THE PERIOD. A FLAT UPPER RIDGE WILL BUILD IN BY TUE
NIGHT IN THE WAKE OF THE EARLY WEEK SYSTEM. WE WILL SEE SFC RIDGING
TAKE CONTROL OF THE WEATHER FOR WED AND MOSTLY THU KEEPING MOST OF
THE AREA DRY. AS SRLY FLOW INCREASES ON THU...WE WILL SEE QUITE WARM
TEMPS MOVE IN. THE AREA SHOULD BE WELL INTO THE 80S BY THU WITH H850
TEMPS INCREASING TO THE UPPER TEENS C. THIS COULD BE A BIT
CONSERVATIVE FOR MAX TEMPS.

THE ONLY UNSETTLED PERIOD LOOKS TO BE DURING THE LATE THU THROUGH
EARLY SAT TIME FRAME. WE WILL SEE OUR FLAT UPPER RIDGE BE PUSHED OUT
BY AN UPPER TROUGH EXPECTED TO EXTEND FROM CENTRAL CANADA TO THE NRN
ROCKIES ON THU. THIS UPPER TROUGH WILL PUSH A COLD FRONT INTO THE
AREA CENTERED ON THE DAY ON FRI RIGHT NOW. THIS FRONT SHOULD MOVE
INTO A FAIR AMOUNT OF INSTABILITY...HELPING TO PRODUCE SHOWERS AND
STORMS.

THIS FRONT SHOULD CLEAR THE AREA BY SAT MORNING....ALLOWING COOLER
AND DRIER AIR TO FILTER BACK INTO THE AREA FROM THE NORTH.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 724 AM EDT SUN AUG 31 2014

CURRENTLY (11Z) THERE IS A BAND OF IFR CIGS WITH MVFR VISIBILITIES
THROUGH KGRR AND KLAN WHILE KMKG...KAZO AND KBTL ARE VFR. HOWEVER
IR SATELLITE LOOPS THE CLOUDS ARE NOT FAR AWAY FROM THOSE OTHER
SITES. I BELIEVE ALL OF THE TAF SITES WILL HAVE IFR CIGS FOR
SEVERAL HOURS THIS MORNING BEFORE THIS ALL MIXES OUT BY EARLY
AFTERNOON.

THERE IS ENOUGH INSTABILITY FOR SHOWERS TO REDEVELOP THIS
AFTERNOON. HOWEVER... THE ONLY LOCATIONS WHERE THERE IS ENOUGH
SURFACE CONVERGENCE FOR THOSE SHOWERS TO BE FORCED IS FOR THE
I-94 TAF SITES. THAT IS WHERE THE FRONT WILL BE STALLED THIS
AFTERNOON. SO I CONTINUED THE IDEA OF VCSH FOR THOSE TAF SITES.
ACTUALLY A THUNDERSTORM WOULD NOT BE OUT OF THE QUESTION FOR THOSE
TAF SITES.

SKIES SHOULD CLEAR ACROSS THE AREA TONIGHT. THERE SHOULD BE ENOUGH
WIND IN THE BOUNDARY LAYER TO KEEP VFR GOING THROUGH THE NIGHT.

&&

.MARINE...
ISSUED AT 328 AM EDT SUN AUG 31 2014

NO CONCERNS IN THE FIRST 18 HRS OR SO FOR THE NEARSHORE WATERS WITH
LIGHT WINDS EXPECTED. CONDITIONS ARE LOOKING LIKELY FOR ANOTHER
SMALL CRAFT
ADVISORY/BEACH HAZARDS EVENT FOR THE DAY ON MONDAY.

HIGH PRESSURE BUILDING IN ACROSS THE AREA TODAY WILL KEEP THE
GRADIENT LIGHT AND WINDS AT OR BELOW 10 KNOTS FOR THE MOST PART.
WINDS WILL START INCREASING TONIGHT AND COULD BE FLIRTING WITH SMALL
CRAFT ADVISORY CRITERIA JUST AFTER DAYBREAK ON MONDAY AHEAD OF THE
NEXT FRONT. WINDS AND WAVES LOOK LIKE THEY COULD BE A LITTLE
STRONGER/HIGHER COMPARED TO THE PAST EVENT YESTERDAY.


&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...MJS
MARINE...NJJ









000
FXUS63 KGRR 310729
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
329 AM EDT SUN AUG 31 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE

.SYNOPSIS...
ISSUED AT 328 AM EDT SUN AUG 31 2014

HIGH PRESSURE WILL MOVE ACROSS LOWER MICHIGAN TODAY. THIS SHOULD
RESULT IN AT LEAST PARTIAL SUNSHINE ACROSS THE AREA THIS AFTERNOON.
AN ISOLATED THUNDERSTORMS IS POSSIBLE EAST OF US-131 AND SOUTH OF
I-96 DURING THE EARLY TO MID AFTERNOON. EXPECT MOSTLY CLEAR SKIES
TONIGHT WITH LOWS MOSTLY IN THE 60S. A COLD FRONT MOVING INTO THE
AREA BY LATE MONDAY NIGHT WILL RESULT IN THUNDERSTORMS MONDAY
AFTERNOON INTO MONDAY EVENING. SOME OF THESE STORMS COULD BE
STRONG TO SEVERE. TEMPERATURES WILL WARM WITH HIGHS IN THE 80S.
COOLER AND DRIER WEATHER FOLLOWS THE COLD FRONT FOR TUESDAY INTO
WEDNESDAY.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

WE CONTINUE TO TRACK THE POTENTIAL FOR SEVERE STORMS MONDAY
AFTERNOON INTO MONDAY EVENING. OTHERWISE TRANQUIL WEATHER IS
EXPECTED TODAY INTO TONIGHT.

AN UNSEASONABLY STRONG PACIFIC SYSTEM WILL BRING THE POLAR JET
STREAM UNUSUALLY FAR SOUTH FOR EARLY SEPTEMBER (1 IN 10 YEAR RETURN
PERIOD FOR EARLY SEPTEMBER) ON MONDAY. A COUPLE JET FEATURE WILL
HELP FOCUS THUNDERSTORMS SUNDAY NIGHT INTO EARLY MONDAY OVER
MINNESOTA AND WISCONSIN. THIS STRONG UPPER LEVEL JET WILL RESULT
IN A 35 TO 45 KNOT LOW LEVEL JET THAT WILL TRACK ACROSS SOUTHERN
WISCONSIN EARLY MONDAY MORNING THEN LIFT NORTHEAST WILL THE
COUPLED JET CORE INTO UPPER MICHIGAN MONDAY AFTERNOON. THE 1000 TO
850 MOISTURE TRANSPORT VECTORS CONVERGE OVER EASTERN WISCONSIN
DURING THE EARLY TO MID MORNING HOURS OF MONDAY BUT THAT
FEATURE... LIKE THE LOW LEVEL JET ALSO LIFTS NORTHEAST INTO UPPER
MICHIGAN AND EASTERN LAKE SUPERIOR BY EARLY MONDAY AFTERNOON.
MEANWHILE THERE SHOULD BE AT LEAST 1500 J/KG OF MIXED LAYER CAPE
OVER CENTRAL AND EASTERN LOWER MICH GAIN BY EARLY MONDAY
AFTERNOON AND THERE WILL BE 30 TO 40 KNOTS OF DEEP LAYER SHEAR
MONDAY AFTERNOON OVER ALL OF LOWER MICHIGAN. ALL OF THIS WOULD
SUGGEST AT LEAST SOME POTENTIAL FOR A LINE OF THUNDERSTORMS
CROSSING LOWER MICHIGAN DURING THE LATE MORNING INTO MID AFTERNOON.
SOUNDINGS FROM THE GFS SUGGEST THE EQUILIBRIUM LEVEL WILL BE NEAR
THE TROP AND THERE IS A SIGNIFICANT AMOUNT OF CAPE IN THE -10 TO
-30 RANGE SO HAIL WOULD BE POSSIBLE AS WELL AS GUSTY WINDS.

SO...WILL THERE BE SEVERE STORMS OVER SOUTHWEST LOWER MICHIGAN ON
LABOR DAY?  ALL OF THIS SUGGEST SEVERE STORMS ARE SURELY POSSIBLE.
WE ARE IN SLIGHT RISK FROM THE SPC DAY 2 OUTLOOK. HOWEVER THERE
ARE SOME QUESTIONS. FIRST SOUTHWEST MICHIGAN IS IN THE SPEED
DIVERGENCE AREA OF THE LOW LEVEL JET MONDAY AFTERNOON. THAT IS NOT
THE PLACE YOU WOULD WANT TO BE TO GET CONCENTRATED SEVERE STORM
ACTIVITY. ALSO SOUTHWEST MICHIGAN IS IN THE RIGHT FRONT EXIT
REGION OF THE JET WHICH IS ACTUALLY OVER WISCONSIN YET MONDAY
AFTERNOON. THIS IS ALSO NOT CONDUCIVE TO SEVERE STORMS. ANTHER
NEGATIVE IS THE LINE OF STORMS COMING OUT OF WISCONSIN DURING THE
MID MORNING HOURS OF MONDAY. THAT WILL BRING LAYERED CLOUDS ACROSS
THE AREA CUTTING BACK ON SURFACE HEATING. YET GIVEN ALL OF THE
ABOVE THERE STILL AT LEAST A SLIGHT RISK AS SPC INDICATES. WE WILL
HAVE TO WATCH HOW THE CONVECTION ACTUALLY PLAYS OUT MONDAY MORNING
BEFORE WE HAVE A BETTER IDEA OF HOW GREAT THE SEVERE RISK HERE IS
ON LABOR DAY.

THE ENTRANCE REGION OF THAT SAME POLAR JET CORE COMES ACROSS
MICHIGAN EARLY TUESDAY. THAT WILL EDUCE A WAVE ON THE FRONT AND
MAY BRING CONVECTION BACK NORTH INTO SOUTHERN LOWER MICHIGAN
DURING THE EARLY MORNING HOURS OF TUESDAY. WE WILL HAVE TO WATCH
THIS CLOSELY. THESE COULD BE STRONG STORMS TOO IF THE GET THIS FAR
NORTH. ONCE THAT IS THROUGH QUIET WEATHER RETURNS BY TUESDAY
AFTERNOON.




.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

THE LONG TERM PORTION OF THE FCST WILL FEATURE QUIET WEATHER FOR A
GOOD MAJORITY OF THE PERIOD. A FLAT UPPER RIDGE WILL BUILD IN BY TUE
NIGHT IN THE WAKE OF THE EARLY WEEK SYSTEM. WE WILL SEE SFC RIDGING
TAKE CONTROL OF THE WEATHER FOR WED AND MOSTLY THU KEEPING MOST OF
THE AREA DRY. AS SRLY FLOW INCREASES ON THU...WE WILL SEE QUITE WARM
TEMPS MOVE IN. THE AREA SHOULD BE WELL INTO THE 80S BY THU WITH H850
TEMPS INCREASING TO THE UPPER TEENS C. THIS COULD BE A BIT
CONSERVATIVE FOR MAX TEMPS.

THE ONLY UNSETTLED PERIOD LOOKS TO BE DURING THE LATE THU THROUGH
EARLY SAT TIME FRAME. WE WILL SEE OUR FLAT UPPER RIDGE BE PUSHED OUT
BY AN UPPER TROUGH EXPECTED TO EXTEND FROM CENTRAL CANADA TO THE NRN
ROCKIES ON THU. THIS UPPER TROUGH WILL PUSH A COLD FRONT INTO THE
AREA CENTERED ON THE DAY ON FRI RIGHT NOW. THIS FRONT SHOULD MOVE
INTO A FAIR AMOUNT OF INSTABILITY...HELPING TO PRODUCE SHOWERS AND
STORMS.

THIS FRONT SHOULD CLEAR THE AREA BY SAT MORNING....ALLOWING COOLER
AND DRIER AIR TO FILTER BACK INTO THE AREA FROM THE NORTH.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 138 AM EDT SUN AUG 31 2014

THE MAIN CONCERN WITH THE 06Z FCSTS WILL BE FOG/LOW CLOUD
POTENTIAL FOR THIS MORNING. SHOWERS AND STORMS HAVE DROPPED SOUTH
AND WILL ONLY AFFECT KJXN FOR THE NEXT HOUR OR TWO BEFORE MOVING
OUT/ENDING.

FOG/LOW CLOUDS THEN BECOME THE MAIN FOCUS. LOW CLOUDS ARE ALREADY
SPREADING IN FROM THE NORTH TOWARD KMKG AND KGRR. WE EXPECT THAT
THEY WILL EVENTUALLY EXPAND OVER THOSE TERMINALS BY 10-11Z.
FURTHER SOUTH WHERE THERE WAS MORE RAIN AND AHEAD OF THE
FRONT...WE EXPECT LOW CLOUDS TO DEVELOP THERE. THIS IS ALREADY
BECOMING EVIDENT AT KAZO. IFR AND LIFR CIGS ARE LIKELY...AND SOME
FOG WILL BE POSSIBLE WITH THE LIGHT WINDS RIGHT AT THE SFC AND
MOIST AIR MASS.

THIS WILL ALL GRADUALLY LIFT SUN MORNING TO VFR CONDITIONS. WITH
THE FRONT STILL IN THE VICINITY...A FEW SHOWERS MAY POP UP DOWN
SOUTH IN THE AFTERNOON. EVERYONE SHOULD CLEAR OUT THIS EVENING.


&&

.MARINE...
ISSUED AT 328 AM EDT SUN AUG 31 2014

NO CONCERNS IN THE FIRST 18 HRS OR SO FOR THE NEARSHORE WATERS WITH
LIGHT WINDS EXPECTED. CONDITIONS ARE LOOKING LIKELY FOR ANOTHER
SMALL CRAFT
ADVISORY/BEACH HAZARDS EVENT FOR THE DAY ON MONDAY.

HIGH PRESSURE BUILDING IN ACROSS THE AREA TODAY WILL KEEP THE
GRADIENT LIGHT AND WINDS AT OR BELOW 10 KNOTS FOR THE MOST PART.
WINDS WILL START INCREASING TONIGHT AND COULD BE FLIRTING WITH SMALL
CRAFT ADVISORY CRITERIA JUST AFTER DAYBREAK ON MONDAY AHEAD OF THE
NEXT FRONT. WINDS AND WAVES LOOK LIKE THEY COULD BE A LITTLE
STRONGER/HIGHER COMPARED TO THE PAST EVENT YESTERDAY.

&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...NJJ







000
FXUS63 KGRR 310729
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
329 AM EDT SUN AUG 31 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE

.SYNOPSIS...
ISSUED AT 328 AM EDT SUN AUG 31 2014

HIGH PRESSURE WILL MOVE ACROSS LOWER MICHIGAN TODAY. THIS SHOULD
RESULT IN AT LEAST PARTIAL SUNSHINE ACROSS THE AREA THIS AFTERNOON.
AN ISOLATED THUNDERSTORMS IS POSSIBLE EAST OF US-131 AND SOUTH OF
I-96 DURING THE EARLY TO MID AFTERNOON. EXPECT MOSTLY CLEAR SKIES
TONIGHT WITH LOWS MOSTLY IN THE 60S. A COLD FRONT MOVING INTO THE
AREA BY LATE MONDAY NIGHT WILL RESULT IN THUNDERSTORMS MONDAY
AFTERNOON INTO MONDAY EVENING. SOME OF THESE STORMS COULD BE
STRONG TO SEVERE. TEMPERATURES WILL WARM WITH HIGHS IN THE 80S.
COOLER AND DRIER WEATHER FOLLOWS THE COLD FRONT FOR TUESDAY INTO
WEDNESDAY.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

WE CONTINUE TO TRACK THE POTENTIAL FOR SEVERE STORMS MONDAY
AFTERNOON INTO MONDAY EVENING. OTHERWISE TRANQUIL WEATHER IS
EXPECTED TODAY INTO TONIGHT.

AN UNSEASONABLY STRONG PACIFIC SYSTEM WILL BRING THE POLAR JET
STREAM UNUSUALLY FAR SOUTH FOR EARLY SEPTEMBER (1 IN 10 YEAR RETURN
PERIOD FOR EARLY SEPTEMBER) ON MONDAY. A COUPLE JET FEATURE WILL
HELP FOCUS THUNDERSTORMS SUNDAY NIGHT INTO EARLY MONDAY OVER
MINNESOTA AND WISCONSIN. THIS STRONG UPPER LEVEL JET WILL RESULT
IN A 35 TO 45 KNOT LOW LEVEL JET THAT WILL TRACK ACROSS SOUTHERN
WISCONSIN EARLY MONDAY MORNING THEN LIFT NORTHEAST WILL THE
COUPLED JET CORE INTO UPPER MICHIGAN MONDAY AFTERNOON. THE 1000 TO
850 MOISTURE TRANSPORT VECTORS CONVERGE OVER EASTERN WISCONSIN
DURING THE EARLY TO MID MORNING HOURS OF MONDAY BUT THAT
FEATURE... LIKE THE LOW LEVEL JET ALSO LIFTS NORTHEAST INTO UPPER
MICHIGAN AND EASTERN LAKE SUPERIOR BY EARLY MONDAY AFTERNOON.
MEANWHILE THERE SHOULD BE AT LEAST 1500 J/KG OF MIXED LAYER CAPE
OVER CENTRAL AND EASTERN LOWER MICH GAIN BY EARLY MONDAY
AFTERNOON AND THERE WILL BE 30 TO 40 KNOTS OF DEEP LAYER SHEAR
MONDAY AFTERNOON OVER ALL OF LOWER MICHIGAN. ALL OF THIS WOULD
SUGGEST AT LEAST SOME POTENTIAL FOR A LINE OF THUNDERSTORMS
CROSSING LOWER MICHIGAN DURING THE LATE MORNING INTO MID AFTERNOON.
SOUNDINGS FROM THE GFS SUGGEST THE EQUILIBRIUM LEVEL WILL BE NEAR
THE TROP AND THERE IS A SIGNIFICANT AMOUNT OF CAPE IN THE -10 TO
-30 RANGE SO HAIL WOULD BE POSSIBLE AS WELL AS GUSTY WINDS.

SO...WILL THERE BE SEVERE STORMS OVER SOUTHWEST LOWER MICHIGAN ON
LABOR DAY?  ALL OF THIS SUGGEST SEVERE STORMS ARE SURELY POSSIBLE.
WE ARE IN SLIGHT RISK FROM THE SPC DAY 2 OUTLOOK. HOWEVER THERE
ARE SOME QUESTIONS. FIRST SOUTHWEST MICHIGAN IS IN THE SPEED
DIVERGENCE AREA OF THE LOW LEVEL JET MONDAY AFTERNOON. THAT IS NOT
THE PLACE YOU WOULD WANT TO BE TO GET CONCENTRATED SEVERE STORM
ACTIVITY. ALSO SOUTHWEST MICHIGAN IS IN THE RIGHT FRONT EXIT
REGION OF THE JET WHICH IS ACTUALLY OVER WISCONSIN YET MONDAY
AFTERNOON. THIS IS ALSO NOT CONDUCIVE TO SEVERE STORMS. ANTHER
NEGATIVE IS THE LINE OF STORMS COMING OUT OF WISCONSIN DURING THE
MID MORNING HOURS OF MONDAY. THAT WILL BRING LAYERED CLOUDS ACROSS
THE AREA CUTTING BACK ON SURFACE HEATING. YET GIVEN ALL OF THE
ABOVE THERE STILL AT LEAST A SLIGHT RISK AS SPC INDICATES. WE WILL
HAVE TO WATCH HOW THE CONVECTION ACTUALLY PLAYS OUT MONDAY MORNING
BEFORE WE HAVE A BETTER IDEA OF HOW GREAT THE SEVERE RISK HERE IS
ON LABOR DAY.

THE ENTRANCE REGION OF THAT SAME POLAR JET CORE COMES ACROSS
MICHIGAN EARLY TUESDAY. THAT WILL EDUCE A WAVE ON THE FRONT AND
MAY BRING CONVECTION BACK NORTH INTO SOUTHERN LOWER MICHIGAN
DURING THE EARLY MORNING HOURS OF TUESDAY. WE WILL HAVE TO WATCH
THIS CLOSELY. THESE COULD BE STRONG STORMS TOO IF THE GET THIS FAR
NORTH. ONCE THAT IS THROUGH QUIET WEATHER RETURNS BY TUESDAY
AFTERNOON.




.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN AUG 31 2014

THE LONG TERM PORTION OF THE FCST WILL FEATURE QUIET WEATHER FOR A
GOOD MAJORITY OF THE PERIOD. A FLAT UPPER RIDGE WILL BUILD IN BY TUE
NIGHT IN THE WAKE OF THE EARLY WEEK SYSTEM. WE WILL SEE SFC RIDGING
TAKE CONTROL OF THE WEATHER FOR WED AND MOSTLY THU KEEPING MOST OF
THE AREA DRY. AS SRLY FLOW INCREASES ON THU...WE WILL SEE QUITE WARM
TEMPS MOVE IN. THE AREA SHOULD BE WELL INTO THE 80S BY THU WITH H850
TEMPS INCREASING TO THE UPPER TEENS C. THIS COULD BE A BIT
CONSERVATIVE FOR MAX TEMPS.

THE ONLY UNSETTLED PERIOD LOOKS TO BE DURING THE LATE THU THROUGH
EARLY SAT TIME FRAME. WE WILL SEE OUR FLAT UPPER RIDGE BE PUSHED OUT
BY AN UPPER TROUGH EXPECTED TO EXTEND FROM CENTRAL CANADA TO THE NRN
ROCKIES ON THU. THIS UPPER TROUGH WILL PUSH A COLD FRONT INTO THE
AREA CENTERED ON THE DAY ON FRI RIGHT NOW. THIS FRONT SHOULD MOVE
INTO A FAIR AMOUNT OF INSTABILITY...HELPING TO PRODUCE SHOWERS AND
STORMS.

THIS FRONT SHOULD CLEAR THE AREA BY SAT MORNING....ALLOWING COOLER
AND DRIER AIR TO FILTER BACK INTO THE AREA FROM THE NORTH.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 138 AM EDT SUN AUG 31 2014

THE MAIN CONCERN WITH THE 06Z FCSTS WILL BE FOG/LOW CLOUD
POTENTIAL FOR THIS MORNING. SHOWERS AND STORMS HAVE DROPPED SOUTH
AND WILL ONLY AFFECT KJXN FOR THE NEXT HOUR OR TWO BEFORE MOVING
OUT/ENDING.

FOG/LOW CLOUDS THEN BECOME THE MAIN FOCUS. LOW CLOUDS ARE ALREADY
SPREADING IN FROM THE NORTH TOWARD KMKG AND KGRR. WE EXPECT THAT
THEY WILL EVENTUALLY EXPAND OVER THOSE TERMINALS BY 10-11Z.
FURTHER SOUTH WHERE THERE WAS MORE RAIN AND AHEAD OF THE
FRONT...WE EXPECT LOW CLOUDS TO DEVELOP THERE. THIS IS ALREADY
BECOMING EVIDENT AT KAZO. IFR AND LIFR CIGS ARE LIKELY...AND SOME
FOG WILL BE POSSIBLE WITH THE LIGHT WINDS RIGHT AT THE SFC AND
MOIST AIR MASS.

THIS WILL ALL GRADUALLY LIFT SUN MORNING TO VFR CONDITIONS. WITH
THE FRONT STILL IN THE VICINITY...A FEW SHOWERS MAY POP UP DOWN
SOUTH IN THE AFTERNOON. EVERYONE SHOULD CLEAR OUT THIS EVENING.


&&

.MARINE...
ISSUED AT 328 AM EDT SUN AUG 31 2014

NO CONCERNS IN THE FIRST 18 HRS OR SO FOR THE NEARSHORE WATERS WITH
LIGHT WINDS EXPECTED. CONDITIONS ARE LOOKING LIKELY FOR ANOTHER
SMALL CRAFT
ADVISORY/BEACH HAZARDS EVENT FOR THE DAY ON MONDAY.

HIGH PRESSURE BUILDING IN ACROSS THE AREA TODAY WILL KEEP THE
GRADIENT LIGHT AND WINDS AT OR BELOW 10 KNOTS FOR THE MOST PART.
WINDS WILL START INCREASING TONIGHT AND COULD BE FLIRTING WITH SMALL
CRAFT ADVISORY CRITERIA JUST AFTER DAYBREAK ON MONDAY AHEAD OF THE
NEXT FRONT. WINDS AND WAVES LOOK LIKE THEY COULD BE A LITTLE
STRONGER/HIGHER COMPARED TO THE PAST EVENT YESTERDAY.

&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...NJJ








000
FXUS63 KGRR 310538
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
138 AM EDT SUN AUG 31 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 220 PM EDT SAT AUG 30 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION THIS EVENING PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. A WEAK AREA OF HIGH PRESSURE WILL MOVE IN FOR
SUNDAY WITH MAINLY A DRY AND WARM DAY EXPECTED. A COLD FRONT
PUSHES IN FROM THE WEST ON MONDAY. THIS SYSTEM COULD TRIGGER
STRONG TO SEVERE THUNDERSTORMS THAT WOULD PERSIST INTO THE EVENING.

&&

.UPDATE...
ISSUED AT 959 PM EDT SAT AUG 30 2014

NO MAJOR CHANGES TO THE FORECAST THIS EVENING. WE HAVE FRESHENED
UP THE GRIDS AND ZONES TO ACCOUNT FOR THE LATEST RADAR TRENDS.
PCPN IS SHIFTING GRADUALLY TO THE SE AS EXPECTED. SEVERE WEATHER
THREAT IS VERY LIMITED WITH THE HEATING OF THE DAY LOST.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 220 PM EDT SAT AUG 30 2014

THE MAIN CONCERN DEALS WITH THE POTENTIAL FOR SEVERE WEATHER
THIS AFTERNOON AND EVENING ALONG WITH ON MONDAY. SPC MESO PAGE
SHOWS SURFACE BASED CAPE VALUES AROUND 2000 J/KG AND MLCAPE VALUES
OF AROUND 1000 J/KG. ENOUGH INSTABILITY FOR STORMS TO DEVELOP
AIDED BY THE LIFT FROM AN APPROACHING MID LEVEL WAVE. EFFECTIVE
BULK SHEAR AROUND 35 KNOTS AND 0 TO 1 KM SHEAR AROUND 15 KNOTS.
SO A RISK FOR SEVERE WEATHER EXISTS WITH DAMAGING WINDS THE
PRIMARY RISKS...ALONG WITH A SMALL RISK FOR A TORNADO. SO FAR THE
CELLS HAVE STRUGGLED TO KEEP PERSISTENT UPDRAFTS...BUT THAT COULD CHANGE.
SLIGHT RISK CONTINUES.

STORMS WILL WEAKEN BY MIDNIGHT. LESS IN THE WAY OF CONVECTION
EXPECTED LATER TONIGHT THROUGH SUNDAY WITH NO REAL FORCING AROUND.
STILL SOME DAYTIME STORMS COULD POP UP ON SUNDAY GIVEN THE DECENT
HEATING.

STRONG TO SEVERE STORMS ARE A POSSIBILITY ON MONDAY. RIGHT
ENTRANCE REGION OF AN UPPER JET MOVES IN DURING THE DAY WITH
STRONGER INSTABILITY PRESENT. MODELS SHOW THE STRONGER DEEP LAYER
SHEAR ARRIVING IN THE EVENING. ITS POSSIBLE WE COULD SEE SCATTERED
TO NUMEROUS AFTERNOON STORMS DEVELOPING WITH A FEW SEVERE IN THE
AFTERNOON FOLLOWED BY THE ARRIVAL OF A WEAKENING SQUALL LINE
MOVING IN FROM WISCONSIN IN THE EVENING. TIMING WILL LIKELY
DETERMINE HOW MUCH IF ANY SEVERE WEATHER OCCURS. SLIGHT RISK FOR
PARTS OF THE REGION CONTINUES.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 220 PM EDT SAT AUG 30 2014

MORE OF A ZONAL FLOW ARRIVES FOR THE MIDDLE OF NEXT WEEK. THIS
WILL SUPPORT WARMER TEMPERATURES. IT COULD BE UNSETTLED AS WELL
ESPECIALLY WEDNESDAY NIGHT INTO THURSDAY. HARD TO TIME INDIVIDUAL
SHORTWAVES GIVEN THE FAST FLOW THAT WILL BE PRESENT. WILL KEEP THE
RISK FOR SOME STORMS GOING THEN.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 138 AM EDT SUN AUG 31 2014

THE MAIN CONCERN WITH THE 06Z FCSTS WILL BE FOG/LOW CLOUD
POTENTIAL FOR THIS MORNING. SHOWERS AND STORMS HAVE DROPPED SOUTH
AND WILL ONLY AFFECT KJXN FOR THE NEXT HOUR OR TWO BEFORE MOVING
OUT/ENDING.

FOG/LOW CLOUDS THEN BECOME THE MAIN FOCUS. LOW CLOUDS ARE ALREADY
SPREADING IN FROM THE NORTH TOWARD KMKG AND KGRR. WE EXPECT THAT
THEY WILL EVENTUALLY EXPAND OVER THOSE TERMINALS BY 10-11Z.
FURTHER SOUTH WHERE THERE WAS MORE RAIN AND AHEAD OF THE
FRONT...WE EXPECT LOW CLOUDS TO DEVELOP THERE. THIS IS ALREADY
BECOMING EVIDENT AT KAZO. IFR AND LIFR CIGS ARE LIKELY...AND SOME
FOG WILL BE POSSIBLE WITH THE LIGHT WINDS RIGHT AT THE SFC AND
MOIST AIR MASS.

THIS WILL ALL GRADUALLY LIFT SUN MORNING TO VFR CONDITIONS. WITH
THE FRONT STILL IN THE VICINITY...A FEW SHOWERS MAY POP UP DOWN
SOUTH IN THE AFTERNOON. EVERYONE SHOULD CLEAR OUT THIS EVENING.

&&

.MARINE...
ISSUED AT 220 PM EDT SAT AUG 30 2014

BEACH HAZARDS AND SMALL CRAFT ADVISORIES CONTINUE. SOME GUSTS OVER
25 KNOTS ON THE LAKESHORE. WAVES STILL RUNNING 3 TO 5 FEET BUT
THEY WILL DIMINISH AS WITH WINDS SETTLE DOWN THIS EVENING.


&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

UPDATE...NJJ
SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...MJS
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 310538
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
138 AM EDT SUN AUG 31 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 220 PM EDT SAT AUG 30 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION THIS EVENING PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. A WEAK AREA OF HIGH PRESSURE WILL MOVE IN FOR
SUNDAY WITH MAINLY A DRY AND WARM DAY EXPECTED. A COLD FRONT
PUSHES IN FROM THE WEST ON MONDAY. THIS SYSTEM COULD TRIGGER
STRONG TO SEVERE THUNDERSTORMS THAT WOULD PERSIST INTO THE EVENING.

&&

.UPDATE...
ISSUED AT 959 PM EDT SAT AUG 30 2014

NO MAJOR CHANGES TO THE FORECAST THIS EVENING. WE HAVE FRESHENED
UP THE GRIDS AND ZONES TO ACCOUNT FOR THE LATEST RADAR TRENDS.
PCPN IS SHIFTING GRADUALLY TO THE SE AS EXPECTED. SEVERE WEATHER
THREAT IS VERY LIMITED WITH THE HEATING OF THE DAY LOST.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 220 PM EDT SAT AUG 30 2014

THE MAIN CONCERN DEALS WITH THE POTENTIAL FOR SEVERE WEATHER
THIS AFTERNOON AND EVENING ALONG WITH ON MONDAY. SPC MESO PAGE
SHOWS SURFACE BASED CAPE VALUES AROUND 2000 J/KG AND MLCAPE VALUES
OF AROUND 1000 J/KG. ENOUGH INSTABILITY FOR STORMS TO DEVELOP
AIDED BY THE LIFT FROM AN APPROACHING MID LEVEL WAVE. EFFECTIVE
BULK SHEAR AROUND 35 KNOTS AND 0 TO 1 KM SHEAR AROUND 15 KNOTS.
SO A RISK FOR SEVERE WEATHER EXISTS WITH DAMAGING WINDS THE
PRIMARY RISKS...ALONG WITH A SMALL RISK FOR A TORNADO. SO FAR THE
CELLS HAVE STRUGGLED TO KEEP PERSISTENT UPDRAFTS...BUT THAT COULD CHANGE.
SLIGHT RISK CONTINUES.

STORMS WILL WEAKEN BY MIDNIGHT. LESS IN THE WAY OF CONVECTION
EXPECTED LATER TONIGHT THROUGH SUNDAY WITH NO REAL FORCING AROUND.
STILL SOME DAYTIME STORMS COULD POP UP ON SUNDAY GIVEN THE DECENT
HEATING.

STRONG TO SEVERE STORMS ARE A POSSIBILITY ON MONDAY. RIGHT
ENTRANCE REGION OF AN UPPER JET MOVES IN DURING THE DAY WITH
STRONGER INSTABILITY PRESENT. MODELS SHOW THE STRONGER DEEP LAYER
SHEAR ARRIVING IN THE EVENING. ITS POSSIBLE WE COULD SEE SCATTERED
TO NUMEROUS AFTERNOON STORMS DEVELOPING WITH A FEW SEVERE IN THE
AFTERNOON FOLLOWED BY THE ARRIVAL OF A WEAKENING SQUALL LINE
MOVING IN FROM WISCONSIN IN THE EVENING. TIMING WILL LIKELY
DETERMINE HOW MUCH IF ANY SEVERE WEATHER OCCURS. SLIGHT RISK FOR
PARTS OF THE REGION CONTINUES.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 220 PM EDT SAT AUG 30 2014

MORE OF A ZONAL FLOW ARRIVES FOR THE MIDDLE OF NEXT WEEK. THIS
WILL SUPPORT WARMER TEMPERATURES. IT COULD BE UNSETTLED AS WELL
ESPECIALLY WEDNESDAY NIGHT INTO THURSDAY. HARD TO TIME INDIVIDUAL
SHORTWAVES GIVEN THE FAST FLOW THAT WILL BE PRESENT. WILL KEEP THE
RISK FOR SOME STORMS GOING THEN.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 138 AM EDT SUN AUG 31 2014

THE MAIN CONCERN WITH THE 06Z FCSTS WILL BE FOG/LOW CLOUD
POTENTIAL FOR THIS MORNING. SHOWERS AND STORMS HAVE DROPPED SOUTH
AND WILL ONLY AFFECT KJXN FOR THE NEXT HOUR OR TWO BEFORE MOVING
OUT/ENDING.

FOG/LOW CLOUDS THEN BECOME THE MAIN FOCUS. LOW CLOUDS ARE ALREADY
SPREADING IN FROM THE NORTH TOWARD KMKG AND KGRR. WE EXPECT THAT
THEY WILL EVENTUALLY EXPAND OVER THOSE TERMINALS BY 10-11Z.
FURTHER SOUTH WHERE THERE WAS MORE RAIN AND AHEAD OF THE
FRONT...WE EXPECT LOW CLOUDS TO DEVELOP THERE. THIS IS ALREADY
BECOMING EVIDENT AT KAZO. IFR AND LIFR CIGS ARE LIKELY...AND SOME
FOG WILL BE POSSIBLE WITH THE LIGHT WINDS RIGHT AT THE SFC AND
MOIST AIR MASS.

THIS WILL ALL GRADUALLY LIFT SUN MORNING TO VFR CONDITIONS. WITH
THE FRONT STILL IN THE VICINITY...A FEW SHOWERS MAY POP UP DOWN
SOUTH IN THE AFTERNOON. EVERYONE SHOULD CLEAR OUT THIS EVENING.

&&

.MARINE...
ISSUED AT 220 PM EDT SAT AUG 30 2014

BEACH HAZARDS AND SMALL CRAFT ADVISORIES CONTINUE. SOME GUSTS OVER
25 KNOTS ON THE LAKESHORE. WAVES STILL RUNNING 3 TO 5 FEET BUT
THEY WILL DIMINISH AS WITH WINDS SETTLE DOWN THIS EVENING.


&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

UPDATE...NJJ
SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...MJS
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...MJS









000
FXUS63 KGRR 310200
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1000 PM EDT SAT AUG 30 2014

LATEST UPDATE...
UPDATE

.SYNOPSIS...
ISSUED AT 220 PM EDT SAT AUG 30 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION THIS EVENING PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. A WEAK AREA OF HIGH PRESSURE WILL MOVE IN FOR
SUNDAY WITH MAINLY A DRY AND WARM DAY EXPECTED. A COLD FRONT
PUSHES IN FROM THE WEST ON MONDAY. THIS SYSTEM COULD TRIGGER
STRONG TO SEVERE THUNDERSTORMS THAT WOULD PERSIST INTO THE EVENING.

&&

.UPDATE...
ISSUED AT 959 PM EDT SAT AUG 30 2014

NO MAJOR CHANGES TO THE FORECAST THIS EVENING. WE HAVE FRESHENED
UP THE GRIDS AND ZONES TO ACCOUNT FOR THE LATEST RADAR TRENDS.
PCPN IS SHIFTING GRADUALLY TO THE SE AS EXPECTED. SEVERE WEATHER
THREAT IS VERY LIMITED WITH THE HEATING OF THE DAY LOST.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 220 PM EDT SAT AUG 30 2014

THE MAIN CONCERN DEALS WITH THE POTENTIAL FOR SEVERE WEATHER
THIS AFTERNOON AND EVENING ALONG WITH ON MONDAY. SPC MESO PAGE
SHOWS SURFACE BASED CAPE VALUES AROUND 2000 J/KG AND MLCAPE VALUES
OF AROUND 1000 J/KG. ENOUGH INSTABILITY FOR STORMS TO DEVELOP
AIDED BY THE LIFT FROM AN APPROACHING MID LEVEL WAVE. EFFECTIVE
BULK SHEAR AROUND 35 KNOTS AND 0 TO 1 KM SHEAR AROUND 15 KNOTS.
SO A RISK FOR SEVERE WEATHER EXISTS WITH DAMAGING WINDS THE
PRIMARY RISKS...ALONG WITH A SMALL RISK FOR A TORNADO. SO FAR THE
CELLS HAVE STRUGGLED TO KEEP PERSISTENT UPDRAFTS...BUT THAT COULD CHANGE.
SLIGHT RISK CONTINUES.

STORMS WILL WEAKEN BY MIDNIGHT. LESS IN THE WAY OF CONVECTION
EXPECTED LATER TONIGHT THROUGH SUNDAY WITH NO REAL FORCING AROUND.
STILL SOME DAYTIME STORMS COULD POP UP ON SUNDAY GIVEN THE DECENT
HEATING.

STRONG TO SEVERE STORMS ARE A POSSIBILITY ON MONDAY. RIGHT
ENTRANCE REGION OF AN UPPER JET MOVES IN DURING THE DAY WITH
STRONGER INSTABILITY PRESENT. MODELS SHOW THE STRONGER DEEP LAYER
SHEAR ARRIVING IN THE EVENING. ITS POSSIBLE WE COULD SEE SCATTERED
TO NUMEROUS AFTERNOON STORMS DEVELOPING WITH A FEW SEVERE IN THE
AFTERNOON FOLLOWED BY THE ARRIVAL OF A WEAKENING SQUALL LINE
MOVING IN FROM WISCONSIN IN THE EVENING. TIMING WILL LIKELY
DETERMINE HOW MUCH IF ANY SEVERE WEATHER OCCURS. SLIGHT RISK FOR
PARTS OF THE REGION CONTINUES.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 220 PM EDT SAT AUG 30 2014

MORE OF A ZONAL FLOW ARRIVES FOR THE MIDDLE OF NEXT WEEK. THIS
WILL SUPPORT WARMER TEMPERATURES. IT COULD BE UNSETTLED AS WELL
ESPECIALLY WEDNESDAY NIGHT INTO THURSDAY. HARD TO TIME INDIVIDUAL
SHORTWAVES GIVEN THE FAST FLOW THAT WILL BE PRESENT. WILL KEEP THE
RISK FOR SOME STORMS GOING THEN.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 749 PM EDT SAT AUG 30 2014

VFR CONDITIONS ARE IN PLACE ACROSS THE AREA AT 2345Z...OUTSIDE OF
THE SCATTERED THUNDERSTORMS THAT ARE OCCURRING. THUNDERSTORMS
SHOULD CONTINUE TO DIMINISH IN COVERAGE AND INTENSITY THIS
EVENING...BUT SOME LOCAL MVFR CONDITIONS REMAIN POSSIBLE IN STORMS
THROUGH ABOUT 03Z.

VFR CONDITIONS WILL PERSIST FOR A WHILE THIS EVENING AFTER THE
STORMS END BEFORE SOME MVFR CEILINGS/VSBYS DEVELOP OVERHEAD AROUND
07Z. CONDITIONS SHOULD DROP FURTHER AROUND 10Z TO IFR IN MOST
LOCATIONS. MODEL GUIDANCE INDICATES THE POTENTIAL TO GO FURTHER
DOWNHILL TO LIFR/VLIFR LEVELS...BUT NOT CONFIDENT ENOUGH TO GO
THAT LOW YET AS WE WILL HAVE SOME WIND AROUND 1000FT.

CONDITIONS SHOULD GRADUALLY IMPROVE THROUGH THE COURSE OF THE
MORNING ON SUNDAY IMPROVING TO VFR IN THE AFTERNOON.


&&

.MARINE...
ISSUED AT 220 PM EDT SAT AUG 30 2014

BEACH HAZARDS AND SMALL CRAFT ADVISORIES CONTINUE. SOME GUSTS OVER
25 KNOTS ON THE LAKESHORE. WAVES STILL RUNNING 3 TO 5 FEET BUT
THEY WILL DIMINISH AS WITH WINDS SETTLE DOWN THIS EVENING.


&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

UPDATE...NJJ
SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...MJS
AVIATION...DUKE
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 310200
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1000 PM EDT SAT AUG 30 2014

LATEST UPDATE...
UPDATE

.SYNOPSIS...
ISSUED AT 220 PM EDT SAT AUG 30 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION THIS EVENING PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. A WEAK AREA OF HIGH PRESSURE WILL MOVE IN FOR
SUNDAY WITH MAINLY A DRY AND WARM DAY EXPECTED. A COLD FRONT
PUSHES IN FROM THE WEST ON MONDAY. THIS SYSTEM COULD TRIGGER
STRONG TO SEVERE THUNDERSTORMS THAT WOULD PERSIST INTO THE EVENING.

&&

.UPDATE...
ISSUED AT 959 PM EDT SAT AUG 30 2014

NO MAJOR CHANGES TO THE FORECAST THIS EVENING. WE HAVE FRESHENED
UP THE GRIDS AND ZONES TO ACCOUNT FOR THE LATEST RADAR TRENDS.
PCPN IS SHIFTING GRADUALLY TO THE SE AS EXPECTED. SEVERE WEATHER
THREAT IS VERY LIMITED WITH THE HEATING OF THE DAY LOST.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 220 PM EDT SAT AUG 30 2014

THE MAIN CONCERN DEALS WITH THE POTENTIAL FOR SEVERE WEATHER
THIS AFTERNOON AND EVENING ALONG WITH ON MONDAY. SPC MESO PAGE
SHOWS SURFACE BASED CAPE VALUES AROUND 2000 J/KG AND MLCAPE VALUES
OF AROUND 1000 J/KG. ENOUGH INSTABILITY FOR STORMS TO DEVELOP
AIDED BY THE LIFT FROM AN APPROACHING MID LEVEL WAVE. EFFECTIVE
BULK SHEAR AROUND 35 KNOTS AND 0 TO 1 KM SHEAR AROUND 15 KNOTS.
SO A RISK FOR SEVERE WEATHER EXISTS WITH DAMAGING WINDS THE
PRIMARY RISKS...ALONG WITH A SMALL RISK FOR A TORNADO. SO FAR THE
CELLS HAVE STRUGGLED TO KEEP PERSISTENT UPDRAFTS...BUT THAT COULD CHANGE.
SLIGHT RISK CONTINUES.

STORMS WILL WEAKEN BY MIDNIGHT. LESS IN THE WAY OF CONVECTION
EXPECTED LATER TONIGHT THROUGH SUNDAY WITH NO REAL FORCING AROUND.
STILL SOME DAYTIME STORMS COULD POP UP ON SUNDAY GIVEN THE DECENT
HEATING.

STRONG TO SEVERE STORMS ARE A POSSIBILITY ON MONDAY. RIGHT
ENTRANCE REGION OF AN UPPER JET MOVES IN DURING THE DAY WITH
STRONGER INSTABILITY PRESENT. MODELS SHOW THE STRONGER DEEP LAYER
SHEAR ARRIVING IN THE EVENING. ITS POSSIBLE WE COULD SEE SCATTERED
TO NUMEROUS AFTERNOON STORMS DEVELOPING WITH A FEW SEVERE IN THE
AFTERNOON FOLLOWED BY THE ARRIVAL OF A WEAKENING SQUALL LINE
MOVING IN FROM WISCONSIN IN THE EVENING. TIMING WILL LIKELY
DETERMINE HOW MUCH IF ANY SEVERE WEATHER OCCURS. SLIGHT RISK FOR
PARTS OF THE REGION CONTINUES.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 220 PM EDT SAT AUG 30 2014

MORE OF A ZONAL FLOW ARRIVES FOR THE MIDDLE OF NEXT WEEK. THIS
WILL SUPPORT WARMER TEMPERATURES. IT COULD BE UNSETTLED AS WELL
ESPECIALLY WEDNESDAY NIGHT INTO THURSDAY. HARD TO TIME INDIVIDUAL
SHORTWAVES GIVEN THE FAST FLOW THAT WILL BE PRESENT. WILL KEEP THE
RISK FOR SOME STORMS GOING THEN.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 749 PM EDT SAT AUG 30 2014

VFR CONDITIONS ARE IN PLACE ACROSS THE AREA AT 2345Z...OUTSIDE OF
THE SCATTERED THUNDERSTORMS THAT ARE OCCURRING. THUNDERSTORMS
SHOULD CONTINUE TO DIMINISH IN COVERAGE AND INTENSITY THIS
EVENING...BUT SOME LOCAL MVFR CONDITIONS REMAIN POSSIBLE IN STORMS
THROUGH ABOUT 03Z.

VFR CONDITIONS WILL PERSIST FOR A WHILE THIS EVENING AFTER THE
STORMS END BEFORE SOME MVFR CEILINGS/VSBYS DEVELOP OVERHEAD AROUND
07Z. CONDITIONS SHOULD DROP FURTHER AROUND 10Z TO IFR IN MOST
LOCATIONS. MODEL GUIDANCE INDICATES THE POTENTIAL TO GO FURTHER
DOWNHILL TO LIFR/VLIFR LEVELS...BUT NOT CONFIDENT ENOUGH TO GO
THAT LOW YET AS WE WILL HAVE SOME WIND AROUND 1000FT.

CONDITIONS SHOULD GRADUALLY IMPROVE THROUGH THE COURSE OF THE
MORNING ON SUNDAY IMPROVING TO VFR IN THE AFTERNOON.


&&

.MARINE...
ISSUED AT 220 PM EDT SAT AUG 30 2014

BEACH HAZARDS AND SMALL CRAFT ADVISORIES CONTINUE. SOME GUSTS OVER
25 KNOTS ON THE LAKESHORE. WAVES STILL RUNNING 3 TO 5 FEET BUT
THEY WILL DIMINISH AS WITH WINDS SETTLE DOWN THIS EVENING.


&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

UPDATE...NJJ
SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...MJS
AVIATION...DUKE
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 302349
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
749 PM EDT SAT AUG 30 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 220 PM EDT SAT AUG 30 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION THIS EVENING PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. A WEAK AREA OF HIGH PRESSURE WILL MOVE IN FOR
SUNDAY WITH MAINLY A DRY AND WARM DAY EXPECTED. A COLD FRONT
PUSHES IN FROM THE WEST ON MONDAY. THIS SYSTEM COULD TRIGGER
STRONG TO SEVERE THUNDERSTORMS THAT WOULD PERSIST INTO THE EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 220 PM EDT SAT AUG 30 2014

THE MAIN CONCERN DEALS WITH THE POTENTIAL FOR SEVERE WEATHER
THIS AFTERNOON AND EVENING ALONG WITH ON MONDAY. SPC MESO PAGE
SHOWS SURFACE BASED CAPE VALUES AROUND 2000 J/KG AND MLCAPE VALUES
OF AROUND 1000 J/KG. ENOUGH INSTABILITY FOR STORMS TO DEVELOP
AIDED BY THE LIFT FROM AN APPROACHING MID LEVEL WAVE. EFFECTIVE
BULK SHEAR AROUND 35 KNOTS AND 0 TO 1 KM SHEAR AROUND 15 KNOTS.
SO A RISK FOR SEVERE WEATHER EXISTS WITH DAMAGING WINDS THE
PRIMARY RISKS...ALONG WITH A SMALL RISK FOR A TORNADO. SO FAR THE
CELLS HAVE STRUGGLED TO KEEP PERSISTENT UPDRAFTS...BUT THAT COULD CHANGE.
SLIGHT RISK CONTINUES.

STORMS WILL WEAKEN BY MIDNIGHT. LESS IN THE WAY OF CONVECTION
EXPECTED LATER TONIGHT THROUGH SUNDAY WITH NO REAL FORCING AROUND.
STILL SOME DAYTIME STORMS COULD POP UP ON SUNDAY GIVEN THE DECENT
HEATING.

STRONG TO SEVERE STORMS ARE A POSSIBILITY ON MONDAY. RIGHT
ENTRANCE REGION OF AN UPPER JET MOVES IN DURING THE DAY WITH
STRONGER INSTABILITY PRESENT. MODELS SHOW THE STRONGER DEEP LAYER
SHEAR ARRIVING IN THE EVENING. ITS POSSIBLE WE COULD SEE SCATTERED
TO NUMEROUS AFTERNOON STORMS DEVELOPING WITH A FEW SEVERE IN THE
AFTERNOON FOLLOWED BY THE ARRIVAL OF A WEAKENING SQUALL LINE
MOVING IN FROM WISCONSIN IN THE EVENING. TIMING WILL LIKELY
DETERMINE HOW MUCH IF ANY SEVERE WEATHER OCCURS. SLIGHT RISK FOR
PARTS OF THE REGION CONTINUES.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 220 PM EDT SAT AUG 30 2014

MORE OF A ZONAL FLOW ARRIVES FOR THE MIDDLE OF NEXT WEEK. THIS
WILL SUPPORT WARMER TEMPERATURES. IT COULD BE UNSETTLED AS WELL
ESPECIALLY WEDNESDAY NIGHT INTO THURSDAY. HARD TO TIME INDIVIDUAL
SHORTWAVES GIVEN THE FAST FLOW THAT WILL BE PRESENT. WILL KEEP THE
RISK FOR SOME STORMS GOING THEN.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 749 PM EDT SAT AUG 30 2014

VFR CONDITIONS ARE IN PLACE ACROSS THE AREA AT 2345Z...OUTSIDE OF
THE SCATTERED THUNDERSTORMS THAT ARE OCCURRING. THUNDERSTORMS
SHOULD CONTINUE TO DIMINISH IN COVERAGE AND INTENSITY THIS
EVENING...BUT SOME LOCAL MVFR CONDITIONS REMAIN POSSIBLE IN STORMS
THROUGH ABOUT 03Z.

VFR CONDITIONS WILL PERSIST FOR A WHILE THIS EVENING AFTER THE
STORMS END BEFORE SOME MVFR CEILINGS/VSBYS DEVELOP OVERHEAD AROUND
07Z. CONDITIONS SHOULD DROP FURTHER AROUND 10Z TO IFR IN MOST
LOCATIONS. MODEL GUIDANCE INDICATES THE POTENTIAL TO GO FURTHER
DOWNHILL TO LIFR/VLIFR LEVELS...BUT NOT CONFIDENT ENOUGH TO GO
THAT LOW YET AS WE WILL HAVE SOME WIND AROUND 1000FT.

CONDITIONS SHOULD GRADUALLY IMPROVE THROUGH THE COURSE OF THE
MORNING ON SUNDAY IMPROVING TO VFR IN THE AFTERNOON.

&&

.MARINE...
ISSUED AT 220 PM EDT SAT AUG 30 2014

BEACH HAZARDS AND SMALL CRAFT ADVISORIES CONTINUE. SOME GUSTS OVER
25 KNOTS ON THE LAKESHORE. WAVES STILL RUNNING 3 TO 5 FEET BUT
THEY WILL DIMINISH AS WITH WINDS SETTLE DOWN THIS EVENING.

&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 11 PM EDT THIS EVENING FOR MIZ037-
     043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...MJS
AVIATION...DUKE
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 302349
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
749 PM EDT SAT AUG 30 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 220 PM EDT SAT AUG 30 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION THIS EVENING PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. A WEAK AREA OF HIGH PRESSURE WILL MOVE IN FOR
SUNDAY WITH MAINLY A DRY AND WARM DAY EXPECTED. A COLD FRONT
PUSHES IN FROM THE WEST ON MONDAY. THIS SYSTEM COULD TRIGGER
STRONG TO SEVERE THUNDERSTORMS THAT WOULD PERSIST INTO THE EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 220 PM EDT SAT AUG 30 2014

THE MAIN CONCERN DEALS WITH THE POTENTIAL FOR SEVERE WEATHER
THIS AFTERNOON AND EVENING ALONG WITH ON MONDAY. SPC MESO PAGE
SHOWS SURFACE BASED CAPE VALUES AROUND 2000 J/KG AND MLCAPE VALUES
OF AROUND 1000 J/KG. ENOUGH INSTABILITY FOR STORMS TO DEVELOP
AIDED BY THE LIFT FROM AN APPROACHING MID LEVEL WAVE. EFFECTIVE
BULK SHEAR AROUND 35 KNOTS AND 0 TO 1 KM SHEAR AROUND 15 KNOTS.
SO A RISK FOR SEVERE WEATHER EXISTS WITH DAMAGING WINDS THE
PRIMARY RISKS...ALONG WITH A SMALL RISK FOR A TORNADO. SO FAR THE
CELLS HAVE STRUGGLED TO KEEP PERSISTENT UPDRAFTS...BUT THAT COULD CHANGE.
SLIGHT RISK CONTINUES.

STORMS WILL WEAKEN BY MIDNIGHT. LESS IN THE WAY OF CONVECTION
EXPECTED LATER TONIGHT THROUGH SUNDAY WITH NO REAL FORCING AROUND.
STILL SOME DAYTIME STORMS COULD POP UP ON SUNDAY GIVEN THE DECENT
HEATING.

STRONG TO SEVERE STORMS ARE A POSSIBILITY ON MONDAY. RIGHT
ENTRANCE REGION OF AN UPPER JET MOVES IN DURING THE DAY WITH
STRONGER INSTABILITY PRESENT. MODELS SHOW THE STRONGER DEEP LAYER
SHEAR ARRIVING IN THE EVENING. ITS POSSIBLE WE COULD SEE SCATTERED
TO NUMEROUS AFTERNOON STORMS DEVELOPING WITH A FEW SEVERE IN THE
AFTERNOON FOLLOWED BY THE ARRIVAL OF A WEAKENING SQUALL LINE
MOVING IN FROM WISCONSIN IN THE EVENING. TIMING WILL LIKELY
DETERMINE HOW MUCH IF ANY SEVERE WEATHER OCCURS. SLIGHT RISK FOR
PARTS OF THE REGION CONTINUES.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 220 PM EDT SAT AUG 30 2014

MORE OF A ZONAL FLOW ARRIVES FOR THE MIDDLE OF NEXT WEEK. THIS
WILL SUPPORT WARMER TEMPERATURES. IT COULD BE UNSETTLED AS WELL
ESPECIALLY WEDNESDAY NIGHT INTO THURSDAY. HARD TO TIME INDIVIDUAL
SHORTWAVES GIVEN THE FAST FLOW THAT WILL BE PRESENT. WILL KEEP THE
RISK FOR SOME STORMS GOING THEN.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 749 PM EDT SAT AUG 30 2014

VFR CONDITIONS ARE IN PLACE ACROSS THE AREA AT 2345Z...OUTSIDE OF
THE SCATTERED THUNDERSTORMS THAT ARE OCCURRING. THUNDERSTORMS
SHOULD CONTINUE TO DIMINISH IN COVERAGE AND INTENSITY THIS
EVENING...BUT SOME LOCAL MVFR CONDITIONS REMAIN POSSIBLE IN STORMS
THROUGH ABOUT 03Z.

VFR CONDITIONS WILL PERSIST FOR A WHILE THIS EVENING AFTER THE
STORMS END BEFORE SOME MVFR CEILINGS/VSBYS DEVELOP OVERHEAD AROUND
07Z. CONDITIONS SHOULD DROP FURTHER AROUND 10Z TO IFR IN MOST
LOCATIONS. MODEL GUIDANCE INDICATES THE POTENTIAL TO GO FURTHER
DOWNHILL TO LIFR/VLIFR LEVELS...BUT NOT CONFIDENT ENOUGH TO GO
THAT LOW YET AS WE WILL HAVE SOME WIND AROUND 1000FT.

CONDITIONS SHOULD GRADUALLY IMPROVE THROUGH THE COURSE OF THE
MORNING ON SUNDAY IMPROVING TO VFR IN THE AFTERNOON.

&&

.MARINE...
ISSUED AT 220 PM EDT SAT AUG 30 2014

BEACH HAZARDS AND SMALL CRAFT ADVISORIES CONTINUE. SOME GUSTS OVER
25 KNOTS ON THE LAKESHORE. WAVES STILL RUNNING 3 TO 5 FEET BUT
THEY WILL DIMINISH AS WITH WINDS SETTLE DOWN THIS EVENING.

&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 11 PM EDT THIS EVENING FOR MIZ037-
     043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...MJS
AVIATION...DUKE
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 301842
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
242 PM EDT SAT AUG 30 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE

.SYNOPSIS...
ISSUED AT 220 PM EDT SAT AUG 30 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION THIS EVENING PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. A WEAK AREA OF HIGH PRESSURE WILL MOVE IN FOR
SUNDAY WITH MAINLY A DRY AND WARM DAY EXPECTED. A COLD FRONT
PUSHES IN FROM THE WEST ON MONDAY. THIS SYSTEM COULD TRIGGER
STRONG TO SEVERE THUNDERSTORMS THAT WOULD PERSIST INTO THE EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 220 PM EDT SAT AUG 30 2014

THE MAIN CONCERN DEALS WITH THE POTENTIAL FOR SEVERE WEATHER
THIS AFTERNOON AND EVENING ALONG WITH ON MONDAY. SPC MESO PAGE
SHOWS SURFACE BASED CAPE VALUES AROUND 2000 J/KG AND MLCAPE VALUES
OF AROUND 1000 J/KG. ENOUGH INSTABILITY FOR STORMS TO DEVELOP
AIDED BY THE LIFT FROM AN APPROACHING MID LEVEL WAVE. EFFECTIVE
BULK SHEAR AROUND 35 KNOTS AND 0 TO 1 KM SHEAR AROUND 15 KNOTS.
SO A RISK FOR SEVERE WEATHER EXISTS WITH DAMAGING WINDS THE
PRIMARY RISKS...ALONG WITH A SMALL RISK FOR A TORNADO. SO FAR THE
CELLS HAVE STRUGGLED TO KEEP PERSISTENT UPDRAFTS...BUT THAT COULD CHANGE.
SLIGHT RISK CONTINUES.

STORMS WILL WEAKEN BY MIDNIGHT. LESS IN THE WAY OF CONVECTION
EXPECTED LATER TONIGHT THROUGH SUNDAY WITH NO REAL FORCING AROUND.
STILL SOME DAYTIME STORMS COULD POP UP ON SUNDAY GIVEN THE DECENT
HEATING.

STRONG TO SEVERE STORMS ARE A POSSIBILITY ON MONDAY. RIGHT
ENTRANCE REGION OF AN UPPER JET MOVES IN DURING THE DAY WITH
STRONGER INSTABILITY PRESENT. MODELS SHOW THE STRONGER DEEP LAYER
SHEAR ARRIVING IN THE EVENING. ITS POSSIBLE WE COULD SEE SCATTERED
TO NUMEROUS AFTERNOON STORMS DEVELOPING WITH A FEW SEVERE IN THE
AFTERNOON FOLLOWED BY THE ARRIVAL OF A WEAKENING SQUALL LINE
MOVING IN FROM WISCONSIN IN THE EVENING. TIMING WILL LIKELY
DETERMINE HOW MUCH IF ANY SEVERE WEATHER OCCURS. SLIGHT RISK FOR
PARTS OF THE REGION CONTINUES.



.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 220 PM EDT SAT AUG 30 2014

MORE OF A ZONAL FLOW ARRIVES FOR THE MIDDLE OF NEXT WEEK. THIS
WILL SUPPORT WARMER TEMPERATURES. IT COULD BE UNSETTLED AS WELL
ESPECIALLY WEDNESDAY NIGHT INTO THURSDAY. HARD TO TIME INDIVIDUAL
SHORTWAVES GIVEN THE FAST FLOW THAT WILL BE PRESENT. WILL KEEP THE
RISK FOR SOME STORMS GOING THEN.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 145 PM EDT SAT AUG 30 2014

SCATTERED THUNDERSTORMS ARE EXPECTED...ESPECIALLY LATE THIS
AFTERNOON AND EARLY EVENING. THEN THE THREAT OF STORMS WILL BE
EXITING AROUND MIDNIGHT LOCAL TIME.

CONFIDENCE IN WIDESPREAD IFR LATE TONIGHT IN FOG WAS DIMINISHING
DUE TO THE ABUNDANT LOW CLOUDS THAT ARE EXPECTED TO REMAIN OVER
THE AREA. KEPT SOME IFR AROUND...BUT DID NOT HIT IT AS HARD. ANY
IFR SHOULD BE LIFTING OUT OF THE AREA BY LATE SUNDAY MORNING.


&&

.MARINE...
ISSUED AT 220 PM EDT SAT AUG 30 2014

BEACH HAZARDS AND SMALL CRAFT ADVISORIES CONTINUE. SOME GUSTS OVER
25 KNOTS ON THE LAKESHORE. WAVES STILL RUNNING 3 TO 5 FEET BUT
THEY WILL DIMINISH AS WITH WINDS SETTLE DOWN THIS EVENING.

&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 11 PM EDT THIS EVENING FOR MIZ037-
     043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...MJS
AVIATION...JK
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 301842
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
242 PM EDT SAT AUG 30 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE

.SYNOPSIS...
ISSUED AT 220 PM EDT SAT AUG 30 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION THIS EVENING PRODUCING SCATTERED SHOWERS AND
THUNDERSTORMS. A WEAK AREA OF HIGH PRESSURE WILL MOVE IN FOR
SUNDAY WITH MAINLY A DRY AND WARM DAY EXPECTED. A COLD FRONT
PUSHES IN FROM THE WEST ON MONDAY. THIS SYSTEM COULD TRIGGER
STRONG TO SEVERE THUNDERSTORMS THAT WOULD PERSIST INTO THE EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 220 PM EDT SAT AUG 30 2014

THE MAIN CONCERN DEALS WITH THE POTENTIAL FOR SEVERE WEATHER
THIS AFTERNOON AND EVENING ALONG WITH ON MONDAY. SPC MESO PAGE
SHOWS SURFACE BASED CAPE VALUES AROUND 2000 J/KG AND MLCAPE VALUES
OF AROUND 1000 J/KG. ENOUGH INSTABILITY FOR STORMS TO DEVELOP
AIDED BY THE LIFT FROM AN APPROACHING MID LEVEL WAVE. EFFECTIVE
BULK SHEAR AROUND 35 KNOTS AND 0 TO 1 KM SHEAR AROUND 15 KNOTS.
SO A RISK FOR SEVERE WEATHER EXISTS WITH DAMAGING WINDS THE
PRIMARY RISKS...ALONG WITH A SMALL RISK FOR A TORNADO. SO FAR THE
CELLS HAVE STRUGGLED TO KEEP PERSISTENT UPDRAFTS...BUT THAT COULD CHANGE.
SLIGHT RISK CONTINUES.

STORMS WILL WEAKEN BY MIDNIGHT. LESS IN THE WAY OF CONVECTION
EXPECTED LATER TONIGHT THROUGH SUNDAY WITH NO REAL FORCING AROUND.
STILL SOME DAYTIME STORMS COULD POP UP ON SUNDAY GIVEN THE DECENT
HEATING.

STRONG TO SEVERE STORMS ARE A POSSIBILITY ON MONDAY. RIGHT
ENTRANCE REGION OF AN UPPER JET MOVES IN DURING THE DAY WITH
STRONGER INSTABILITY PRESENT. MODELS SHOW THE STRONGER DEEP LAYER
SHEAR ARRIVING IN THE EVENING. ITS POSSIBLE WE COULD SEE SCATTERED
TO NUMEROUS AFTERNOON STORMS DEVELOPING WITH A FEW SEVERE IN THE
AFTERNOON FOLLOWED BY THE ARRIVAL OF A WEAKENING SQUALL LINE
MOVING IN FROM WISCONSIN IN THE EVENING. TIMING WILL LIKELY
DETERMINE HOW MUCH IF ANY SEVERE WEATHER OCCURS. SLIGHT RISK FOR
PARTS OF THE REGION CONTINUES.



.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 220 PM EDT SAT AUG 30 2014

MORE OF A ZONAL FLOW ARRIVES FOR THE MIDDLE OF NEXT WEEK. THIS
WILL SUPPORT WARMER TEMPERATURES. IT COULD BE UNSETTLED AS WELL
ESPECIALLY WEDNESDAY NIGHT INTO THURSDAY. HARD TO TIME INDIVIDUAL
SHORTWAVES GIVEN THE FAST FLOW THAT WILL BE PRESENT. WILL KEEP THE
RISK FOR SOME STORMS GOING THEN.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 145 PM EDT SAT AUG 30 2014

SCATTERED THUNDERSTORMS ARE EXPECTED...ESPECIALLY LATE THIS
AFTERNOON AND EARLY EVENING. THEN THE THREAT OF STORMS WILL BE
EXITING AROUND MIDNIGHT LOCAL TIME.

CONFIDENCE IN WIDESPREAD IFR LATE TONIGHT IN FOG WAS DIMINISHING
DUE TO THE ABUNDANT LOW CLOUDS THAT ARE EXPECTED TO REMAIN OVER
THE AREA. KEPT SOME IFR AROUND...BUT DID NOT HIT IT AS HARD. ANY
IFR SHOULD BE LIFTING OUT OF THE AREA BY LATE SUNDAY MORNING.


&&

.MARINE...
ISSUED AT 220 PM EDT SAT AUG 30 2014

BEACH HAZARDS AND SMALL CRAFT ADVISORIES CONTINUE. SOME GUSTS OVER
25 KNOTS ON THE LAKESHORE. WAVES STILL RUNNING 3 TO 5 FEET BUT
THEY WILL DIMINISH AS WITH WINDS SETTLE DOWN THIS EVENING.

&&

.HYDROLOGY...
ISSUED AT 220 PM EDT SAT AUG 30 2014

PWAT VALUES OVER 1.75 INCHES SUPPORT LOCALLY HEAVY RAIN. STORMS
HAVE BEEN MOVING QUICKLY AND THUS THE DURATION HAS BEEN LIMITED.
WITH SEVERAL ROUNDS OF STORMS POSSIBLE MONDAY INTO MONDAY
NIGHT...WILL NEED TO MONITOR THE HEAVY RAIN POTENTIAL ESPECIALLY
WITH PWAT VALUES UNSEASONABLY HIGH AND STRONGER FORCING MOVING IN.
ELEVATED RISK FOR LOCALLY EXCESSIVE RAIN EXISTS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 11 PM EDT THIS EVENING FOR MIZ037-
     043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...MJS
AVIATION...JK
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 301746
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
146 PM EDT SAT AUG 30 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.

&&

.UPDATE...
ISSUED AT 136 PM EDT SAT AUG 30 2014

INSTABILITY WAS BUILDING SLOWLY AS THE CLOUD COVER WAS ERODING
THIS AFTERNOON. MLCAPE VALUES NEAR 500 J/KG WITH MUCAPE VALUES UP
OVER 1500 J/KG AND EFFECTIVE SHEAR VALUES ARE AROUND 35 KNOTS.
STORMS BEGINNING TO DEVELOP AND A FEW COULD CONTAIN DAMAGING WIND
GUSTS AS INSTABILITY TRIES TO INCREASE. MID LEVEL WAVE MOVING IN
FROM WI WILL HELP TO TRIGGER ADDITIONAL STORMS. CONVECTION WILL
DECREASE THIS EVENING AS THE INSTABILITY WEAKENS.

UPDATE ISSUED AT 1032 AM EDT SAT AUG 30 2014

SATELLITE IMAGERY SHOWS DIMINISHING CLOUDS ACROSS LAKE MI. BASED
ON THE MOVEMENT...WE SHOULD SEE A PERIOD OF SUN THIS AFTERNOON.
AS A RESULT THE UPDATE FEATURES MORE SUNSHINE IN THE GRIDS. THIS
HEATING SUPPORTS THUNDERSTORMS DEVELOPING. WITH A LOW LEVEL JET
MOVING IN...THE STORMS COULD BECOME NUMEROUS. WILL KEEP THE HIGHER
POPS GOING FOR THE AFTERNOON. WILL NEED TO MONITOR THE SEVERE
POTENTIAL AS DEEP LAYER SHEAR CLIMBS ABOVE 30 KNOTS. HRRR RUC
SHOWS VERY LITTLE CONVECTION AFTER 19Z DESPITE THE ARRIVAL OF A
MID LEVEL WAVE.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING FOR OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL RESULT IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 145 PM EDT SAT AUG 30 2014

SCATTERED THUNDERSTORMS ARE EXPECTED...ESPECIALLY LATE THIS
AFTERNOON AND EARLY EVENING. THEN THE THREAT OF STORMS WILL BE
EXITING AROUND MIDNIGHT LOCAL TIME.

CONFIDENCE IN WIDESPREAD IFR LATE TONIGHT IN FOG WAS DIMINISHING
DUE TO THE ABUNDANT LOW CLOUDS THAT ARE EXPECTED TO REMAIN OVER
THE AREA. KEPT SOME IFR AROUND...BUT DID NOT HIT IT AS HARD. ANY
IFR SHOULD BE LIFTING OUT OF THE AREA BY LATE SUNDAY MORNING.

&&

.MARINE...
ISSUED AT 1032 AM EDT SAT AUG 30 2014

WAVES RUNNING 3 TO 5 FEET ALONG THE LAKESHORE. GIVEN THE VEERING
FLOW WITH GUSTS UP AROUND 25 KNOTS...HAZARDOUS CONDITIONS WILL
PERSIST INTO THE AFTERNOON. WINDS AND WAVES WILL GRADUALLY
DIMINISH LATER THIS AFTERNOON AND INTO THE EVENING.


&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 11 PM EDT THIS EVENING FOR MIZ037-
     043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

UPDATE...MJS
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...JK
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 301746
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
146 PM EDT SAT AUG 30 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.

&&

.UPDATE...
ISSUED AT 136 PM EDT SAT AUG 30 2014

INSTABILITY WAS BUILDING SLOWLY AS THE CLOUD COVER WAS ERODING
THIS AFTERNOON. MLCAPE VALUES NEAR 500 J/KG WITH MUCAPE VALUES UP
OVER 1500 J/KG AND EFFECTIVE SHEAR VALUES ARE AROUND 35 KNOTS.
STORMS BEGINNING TO DEVELOP AND A FEW COULD CONTAIN DAMAGING WIND
GUSTS AS INSTABILITY TRIES TO INCREASE. MID LEVEL WAVE MOVING IN
FROM WI WILL HELP TO TRIGGER ADDITIONAL STORMS. CONVECTION WILL
DECREASE THIS EVENING AS THE INSTABILITY WEAKENS.

UPDATE ISSUED AT 1032 AM EDT SAT AUG 30 2014

SATELLITE IMAGERY SHOWS DIMINISHING CLOUDS ACROSS LAKE MI. BASED
ON THE MOVEMENT...WE SHOULD SEE A PERIOD OF SUN THIS AFTERNOON.
AS A RESULT THE UPDATE FEATURES MORE SUNSHINE IN THE GRIDS. THIS
HEATING SUPPORTS THUNDERSTORMS DEVELOPING. WITH A LOW LEVEL JET
MOVING IN...THE STORMS COULD BECOME NUMEROUS. WILL KEEP THE HIGHER
POPS GOING FOR THE AFTERNOON. WILL NEED TO MONITOR THE SEVERE
POTENTIAL AS DEEP LAYER SHEAR CLIMBS ABOVE 30 KNOTS. HRRR RUC
SHOWS VERY LITTLE CONVECTION AFTER 19Z DESPITE THE ARRIVAL OF A
MID LEVEL WAVE.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING FOR OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL RESULT IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 145 PM EDT SAT AUG 30 2014

SCATTERED THUNDERSTORMS ARE EXPECTED...ESPECIALLY LATE THIS
AFTERNOON AND EARLY EVENING. THEN THE THREAT OF STORMS WILL BE
EXITING AROUND MIDNIGHT LOCAL TIME.

CONFIDENCE IN WIDESPREAD IFR LATE TONIGHT IN FOG WAS DIMINISHING
DUE TO THE ABUNDANT LOW CLOUDS THAT ARE EXPECTED TO REMAIN OVER
THE AREA. KEPT SOME IFR AROUND...BUT DID NOT HIT IT AS HARD. ANY
IFR SHOULD BE LIFTING OUT OF THE AREA BY LATE SUNDAY MORNING.

&&

.MARINE...
ISSUED AT 1032 AM EDT SAT AUG 30 2014

WAVES RUNNING 3 TO 5 FEET ALONG THE LAKESHORE. GIVEN THE VEERING
FLOW WITH GUSTS UP AROUND 25 KNOTS...HAZARDOUS CONDITIONS WILL
PERSIST INTO THE AFTERNOON. WINDS AND WAVES WILL GRADUALLY
DIMINISH LATER THIS AFTERNOON AND INTO THE EVENING.


&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 11 PM EDT THIS EVENING FOR MIZ037-
     043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

UPDATE...MJS
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...JK
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 301736
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
136 PM EDT SAT AUG 30 2014

LATEST UPDATE...
UPDATE

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.

&&

.UPDATE...
ISSUED AT 136 PM EDT SAT AUG 30 2014

INSTABILITY WAS BUILDING SLOWLY AS THE CLOUD COVER WAS ERODING
THIS AFTERNOON. MLCAPE VALUES NEAR 500 JKG WITH MUCAPE VALUES UP
OVER 1500 J/KG AND EFFECTIVE SHEAR VALUES ARE AROUND 35 KNOTS.
STORMS BEGINNING TO DEVELOP AND A FEW COULD CONTAIN DAMAGING WIND
GUSTS AS INSTABILITY TRIES TO INCREASE. MID LEVEL WAVE MOVING IN
FROM WI WILL HELP TO TRIGGER ADDITIONAL STORMS. CONVECTION WILL
DECREASE THIS EVENING AS THE INSTABILITY WEAKENS.

UPDATE ISSUED AT 1032 AM EDT SAT AUG 30 2014

SATELLITE IMAGERY SHOWS DIMINISHING CLOUDS ACROSS LAKE MI. BASED
ON THE MOVEMENT...WE SHOULD SEE A PERIOD OF SUN THIS AFTERNOON.
AS A RESULT THE UPDATE FEATURES MORE SUNSHINE IN THE GRIDS. THIS
HEATING SUPPORTS THUNDERSTORMS DEVELOPING. WITH A LOW LEVEL JET
MOVING IN...THE STORMS COULD BECOME NUMEROUS. WILL KEEP THE HIGHER
POPS GOING FOR THE AFTERNOON. WILL NEED TO MONITOR THE SEVERE
POTENTIAL AS DEEP LAYER SHEAR CLIMBS ABOVE 30 KNOTS. HRRR RUC
SHOWS VERY LITTLE CONVECTION AFTER 19Z DESPITE THE ARRIVAL OF A
MID LEVEL WAVE.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING FOR OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL RESULT IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 732 AM EDT SAT AUG 30 2014

WHILE IT SHOWERS AND ISOLATED THUNDERSTORMS WILL BE AROUND TODAY
IT WOULD SEEM THE LOW LEVELS ARE DRY ENOUGH THAT CIGS/VSBY WILL
LARGELY BE VFR. I PUT VCTS THIS AFTERNOON AS IT IS EXPECTED SOME
CONVECTION WILL BE AROUND AHEAD OF THE WEAK COLD FRONT BUT THE
ACTIVITY WILL NOT BE CONCENTRATED ENOUGH TO NAIL DOWN THE TIMING
AT THIS POINT. TONIGHT ONCE THE FRONT COMES THROUGH IT WILL STALL
AND WINDS WILL BECOME LIGHT. I WOULD EXPECT LOW CIGS AND SOME IFR
FOG TO DEVELOP TOWARD SUNRISE SUNDAY.


&&

.MARINE...
ISSUED AT 1032 AM EDT SAT AUG 30 2014

WAVES RUNNING 3 TO 5 FEET ALONG THE LAKESHORE. GIVEN THE VEERING
FLOW WITH GUSTS UP AROUND 25 KNOTS...HAZARDOUS CONDITIONS WILL
PERSIST INTO THE AFTERNOON. WINDS AND WAVES WILL GRADUALLY
DIMINISH LATER THIS AFTERNOON AND INTO THE EVENING.


&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 11 PM EDT THIS EVENING FOR MIZ037-
     043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

UPDATE...MJS
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 301441
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1041 AM EDT SAT AUG 30 2014

LATEST UPDATE...
UPDATE/MARINE

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.

&&

.UPDATE...
ISSUED AT 1032 AM EDT SAT AUG 30 2014

SATELLITE IMAGERY SHOWS DIMINISHING CLOUDS ACROSS LAKE MI. BASED
ON THE MOVEMENT...WE SHOULD SEE A PERIOD OF SUN THIS AFTERNOON.
AS A RESULT THE UPDATE FEATURES MORE SUNSHINE IN THE GRIDS. THIS
HEATING SUPPORTS THUNDERSTORMS DEVELOPING. WITH A LOW LEVEL JET
MOVING IN...THE STORMS COULD BECOME NUMEROUS. WILL KEEP THE HIGHER
POPS GOING FOR THE AFTERNOON. WILL NEED TO MONITOR THE SEVERE
POTENTIAL AS DEEP LAYER SHEAR CLIMBS ABOVE 30 KNOTS. HRRR RUC
SHOWS VERY LITTLE CONVECTION AFTER 19Z DESPITE THE ARRIVAL OF A
MID LEVEL WAVE.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING FOR OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL RESULT IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 732 AM EDT SAT AUG 30 2014

WHILE IT SHOWERS AND ISOLATED THUNDERSTORMS WILL BE AROUND TODAY
IT WOULD SEEM THE LOW LEVELS ARE DRY ENOUGH THAT CIGS/VSBY WILL
LARGELY BE VFR. I PUT VCTS THIS AFTERNOON AS IT IS EXPECTED SOME
CONVECTION WILL BE AROUND AHEAD OF THE WEAK COLD FRONT BUT THE
ACTIVITY WILL NOT BE CONCENTRATED ENOUGH TO NAIL DOWN THE TIMING
AT THIS POINT. TONIGHT ONCE THE FRONT COMES THROUGH IT WILL STALL
AND WINDS WILL BECOME LIGHT. I WOULD EXPECT LOW CIGS AND SOME IFR
FOG TO DEVELOP TOWARD SUNRISE SUNDAY.


&&

.MARINE...
ISSUED AT 1032 AM EDT SAT AUG 30 2014

WAVES RUNNING 3 TO 5 FEET ALONG THE LAKESHORE. GIVEN THE VEERING
FLOW WITH GUSTS UP AROUND 25 KNOTS...HAZARDOUS CONDITIONS WILL
PERSIST INTO THE AFTERNOON. WINDS AND WAVES WILL GRADUALLY
DIMINISH LATER THIS AFTERNOON AND INTO THE EVENING.

&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

UPDATE...MJS
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 301441
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1041 AM EDT SAT AUG 30 2014

LATEST UPDATE...
UPDATE/MARINE

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.

&&

.UPDATE...
ISSUED AT 1032 AM EDT SAT AUG 30 2014

SATELLITE IMAGERY SHOWS DIMINISHING CLOUDS ACROSS LAKE MI. BASED
ON THE MOVEMENT...WE SHOULD SEE A PERIOD OF SUN THIS AFTERNOON.
AS A RESULT THE UPDATE FEATURES MORE SUNSHINE IN THE GRIDS. THIS
HEATING SUPPORTS THUNDERSTORMS DEVELOPING. WITH A LOW LEVEL JET
MOVING IN...THE STORMS COULD BECOME NUMEROUS. WILL KEEP THE HIGHER
POPS GOING FOR THE AFTERNOON. WILL NEED TO MONITOR THE SEVERE
POTENTIAL AS DEEP LAYER SHEAR CLIMBS ABOVE 30 KNOTS. HRRR RUC
SHOWS VERY LITTLE CONVECTION AFTER 19Z DESPITE THE ARRIVAL OF A
MID LEVEL WAVE.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING FOR OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL RESULT IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 732 AM EDT SAT AUG 30 2014

WHILE IT SHOWERS AND ISOLATED THUNDERSTORMS WILL BE AROUND TODAY
IT WOULD SEEM THE LOW LEVELS ARE DRY ENOUGH THAT CIGS/VSBY WILL
LARGELY BE VFR. I PUT VCTS THIS AFTERNOON AS IT IS EXPECTED SOME
CONVECTION WILL BE AROUND AHEAD OF THE WEAK COLD FRONT BUT THE
ACTIVITY WILL NOT BE CONCENTRATED ENOUGH TO NAIL DOWN THE TIMING
AT THIS POINT. TONIGHT ONCE THE FRONT COMES THROUGH IT WILL STALL
AND WINDS WILL BECOME LIGHT. I WOULD EXPECT LOW CIGS AND SOME IFR
FOG TO DEVELOP TOWARD SUNRISE SUNDAY.


&&

.MARINE...
ISSUED AT 1032 AM EDT SAT AUG 30 2014

WAVES RUNNING 3 TO 5 FEET ALONG THE LAKESHORE. GIVEN THE VEERING
FLOW WITH GUSTS UP AROUND 25 KNOTS...HAZARDOUS CONDITIONS WILL
PERSIST INTO THE AFTERNOON. WINDS AND WAVES WILL GRADUALLY
DIMINISH LATER THIS AFTERNOON AND INTO THE EVENING.

&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

UPDATE...MJS
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 301132
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
732 AM EDT SAT AUG 30 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING FOR OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL RESULT IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 732 AM EDT SAT AUG 30 2014

WHILE IT SHOWERS AND ISOLATED THUNDERSTORMS WILL BE AROUND TODAY
IT WOULD SEEM THE LOW LEVELS ARE DRY ENOUGH THAT CIGS/VSBY WILL
LARGELY BE VFR. I PUT VCTS THIS AFTERNOON AS IT IS EXPECTED SOME
CONVECTION WILL BE AROUND AHEAD OF THE WEAK COLD FRONT BUT THE
ACTIVITY WILL NOT BE CONCENTRATED ENOUGH TO NAIL DOWN THE TIMING
AT THIS POINT. TONIGHT ONCE THE FRONT COMES THROUGH IT WILL STALL
AND WINDS WILL BECOME LIGHT. I WOULD EXPECT LOW CIGS AND SOME IFR
FOG TO DEVELOP TOWARD SUNRISE SUNDAY.

&&

.MARINE...
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE WILL BE LEAVING THE MARINE AND BEACH HEADLINES AS IS THIS
MORNING. WINDS ARE UP NEAR SMALL CRAFT ADVISORY CRITERIA AT MANY
LOCATIONS ALONG THE COAST. WAVES ARE A BIT MORE MARGINAL...HOWEVER
THEY SHOULD BUILD A BIT AS THE FLOW GOES FROM OFFSHORE TO MORE
ONSHORE THIS AFTERNOON. WINDS WILL REMAIN UP THROUGH THE DAY TODAY
BEFORE THEY DIMINISH THIS EVENING AND TONIGHT.

ANOTHER GOOD POTENTIAL OF STRONGER WINDS LOOKS POISED TO MOVE IN ON
MON WITH THE STRONGER WINDS AHEAD OF THE COLD FRONT. SMALL CRAFT
ADVISORIES AND BEACH HAZARDS STATEMENTS LOOK LIKELY FOR MON.


&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...MJS
MARINE...NJJ








000
FXUS63 KGRR 301132
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
732 AM EDT SAT AUG 30 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING FOR OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL RESULT IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 732 AM EDT SAT AUG 30 2014

WHILE IT SHOWERS AND ISOLATED THUNDERSTORMS WILL BE AROUND TODAY
IT WOULD SEEM THE LOW LEVELS ARE DRY ENOUGH THAT CIGS/VSBY WILL
LARGELY BE VFR. I PUT VCTS THIS AFTERNOON AS IT IS EXPECTED SOME
CONVECTION WILL BE AROUND AHEAD OF THE WEAK COLD FRONT BUT THE
ACTIVITY WILL NOT BE CONCENTRATED ENOUGH TO NAIL DOWN THE TIMING
AT THIS POINT. TONIGHT ONCE THE FRONT COMES THROUGH IT WILL STALL
AND WINDS WILL BECOME LIGHT. I WOULD EXPECT LOW CIGS AND SOME IFR
FOG TO DEVELOP TOWARD SUNRISE SUNDAY.

&&

.MARINE...
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE WILL BE LEAVING THE MARINE AND BEACH HEADLINES AS IS THIS
MORNING. WINDS ARE UP NEAR SMALL CRAFT ADVISORY CRITERIA AT MANY
LOCATIONS ALONG THE COAST. WAVES ARE A BIT MORE MARGINAL...HOWEVER
THEY SHOULD BUILD A BIT AS THE FLOW GOES FROM OFFSHORE TO MORE
ONSHORE THIS AFTERNOON. WINDS WILL REMAIN UP THROUGH THE DAY TODAY
BEFORE THEY DIMINISH THIS EVENING AND TONIGHT.

ANOTHER GOOD POTENTIAL OF STRONGER WINDS LOOKS POISED TO MOVE IN ON
MON WITH THE STRONGER WINDS AHEAD OF THE COLD FRONT. SMALL CRAFT
ADVISORIES AND BEACH HAZARDS STATEMENTS LOOK LIKELY FOR MON.


&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...MJS
MARINE...NJJ







000
FXUS63 KGRR 300732 CCA
AFDGRR

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
331 AM EDT SAT AUG 30 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.


&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014


WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING FOR OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL REUSTL IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.


&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 153 AM EDT SAT AUG 30 2014

PCPN/CONVECTION TRENDS ARE THE MAIN CONCERNS FOR THE 06Z FCST
PERIOD. THE DETAILS IN THE CONVECTION TRENDS ARE STILL A BIT
UNCERTAIN THROUGH MOST OF THE PERIOD. WE CAN NOT RULE OUT A POP UP
SHOWER OR EVEN STORM REALLY AT ANY POINT THROUGH ABOUT 01-02Z SUN.

THERE DO LOOK TO BE TWO BETTER OPPORTUNITIES. THE FIRST WILL START
AFFECTING KMKG AROUND 09Z OR SO AND THEN SPREAD TO THE EAST. THIS
WILL LIKELY BE MORE SHOWERS THAN STORMS...SO WE HAVE GONE WITH
VCSH AND A TEMPO GROUP. THE SECOND IS AFTER 18Z THIS AFTERNOON AS
THE CENTER OF THE SYSTEM MOVES IN AND HEATING OF THE DAY STARTS TO
HELP POP SHOWERS AND STORMS.

WE BELIEVE AS THE LOW STARTS TO MOVE EAST OF THE AREA AFTER ABOUT
01-02Z SUN...PCPN WILL END. WE COULD SEE SOME RESIDUAL MVFR CIGS
HOLD IN THEN THROUGH THE END OF THE FCST PERIOD.


&&

.MARINE...
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE WILL BE LEAVING THE MARINE AND BEACH HEADLINES AS IS THIS
MORNING. WINDS ARE UP NEAR SMALL CRAFT ADVISORY CRITERIA AT MANY
LOCATIONS ALONG THE COAST. WAVES ARE A BIT MORE MARGINAL...HOWEVER
THEY SHOULD BUILD A BIT AS THE FLOW GOES FROM OFFSHORE TO MORE
ONSHORE THIS AFTERNOON. WINDS WILL REMAIN UP THROUGH THE DAY TODAY
BEFORE THEY DIMINISH THIS EVENING AND TONIGHT.

ANOTHER GOOD POTENTIAL OF STRONGER WINDS LOOKS POISED TO MOVE IN ON
MON WITH THE STRONGER WINDS AHEAD OF THE COLD FRONT. SMALL CRAFT
ADVISORIES AND BEACH HAZARDS STATEMENTS LOOK LIKELY FOR MON.

&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...NJJ










000
FXUS63 KGRR 300732 CCA
AFDGRR

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
331 AM EDT SAT AUG 30 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.


&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014


WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING FOR OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL REUSTL IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.


&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 153 AM EDT SAT AUG 30 2014

PCPN/CONVECTION TRENDS ARE THE MAIN CONCERNS FOR THE 06Z FCST
PERIOD. THE DETAILS IN THE CONVECTION TRENDS ARE STILL A BIT
UNCERTAIN THROUGH MOST OF THE PERIOD. WE CAN NOT RULE OUT A POP UP
SHOWER OR EVEN STORM REALLY AT ANY POINT THROUGH ABOUT 01-02Z SUN.

THERE DO LOOK TO BE TWO BETTER OPPORTUNITIES. THE FIRST WILL START
AFFECTING KMKG AROUND 09Z OR SO AND THEN SPREAD TO THE EAST. THIS
WILL LIKELY BE MORE SHOWERS THAN STORMS...SO WE HAVE GONE WITH
VCSH AND A TEMPO GROUP. THE SECOND IS AFTER 18Z THIS AFTERNOON AS
THE CENTER OF THE SYSTEM MOVES IN AND HEATING OF THE DAY STARTS TO
HELP POP SHOWERS AND STORMS.

WE BELIEVE AS THE LOW STARTS TO MOVE EAST OF THE AREA AFTER ABOUT
01-02Z SUN...PCPN WILL END. WE COULD SEE SOME RESIDUAL MVFR CIGS
HOLD IN THEN THROUGH THE END OF THE FCST PERIOD.


&&

.MARINE...
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE WILL BE LEAVING THE MARINE AND BEACH HEADLINES AS IS THIS
MORNING. WINDS ARE UP NEAR SMALL CRAFT ADVISORY CRITERIA AT MANY
LOCATIONS ALONG THE COAST. WAVES ARE A BIT MORE MARGINAL...HOWEVER
THEY SHOULD BUILD A BIT AS THE FLOW GOES FROM OFFSHORE TO MORE
ONSHORE THIS AFTERNOON. WINDS WILL REMAIN UP THROUGH THE DAY TODAY
BEFORE THEY DIMINISH THIS EVENING AND TONIGHT.

ANOTHER GOOD POTENTIAL OF STRONGER WINDS LOOKS POISED TO MOVE IN ON
MON WITH THE STRONGER WINDS AHEAD OF THE COLD FRONT. SMALL CRAFT
ADVISORIES AND BEACH HAZARDS STATEMENTS LOOK LIKELY FOR MON.

&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...NJJ









000
FXUS63 KGRR 300729
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
329 AM EDT SAT AUG 30 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.


&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014


WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING OVER OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL REUSTL IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.


&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 153 AM EDT SAT AUG 30 2014

PCPN/CONVECTION TRENDS ARE THE MAIN CONCERNS FOR THE 06Z FCST
PERIOD. THE DETAILS IN THE CONVECTION TRENDS ARE STILL A BIT
UNCERTAIN THROUGH MOST OF THE PERIOD. WE CAN NOT RULE OUT A POP UP
SHOWER OR EVEN STORM REALLY AT ANY POINT THROUGH ABOUT 01-02Z SUN.

THERE DO LOOK TO BE TWO BETTER OPPORTUNITIES. THE FIRST WILL START
AFFECTING KMKG AROUND 09Z OR SO AND THEN SPREAD TO THE EAST. THIS
WILL LIKELY BE MORE SHOWERS THAN STORMS...SO WE HAVE GONE WITH
VCSH AND A TEMPO GROUP. THE SECOND IS AFTER 18Z THIS AFTERNOON AS
THE CENTER OF THE SYSTEM MOVES IN AND HEATING OF THE DAY STARTS TO
HELP POP SHOWERS AND STORMS.

WE BELIEVE AS THE LOW STARTS TO MOVE EAST OF THE AREA AFTER ABOUT
01-02Z SUN...PCPN WILL END. WE COULD SEE SOME RESIDUAL MVFR CIGS
HOLD IN THEN THROUGH THE END OF THE FCST PERIOD.


&&

.MARINE...
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE WILL BE LEAVING THE MARINE AND BEACH HEADLINES AS IS THIS
MORNING. WINDS ARE UP NEAR SMALL CRAFT ADVISORY CRITERIA AT MANY
LOCATIONS ALONG THE COAST. WAVES ARE A BIT MORE MARGINAL...HOWEVER
THEY SHOULD BUILD A BIT AS THE FLOW GOES FROM OFFSHORE TO MORE
ONSHORE THIS AFTERNOON. WINDS WILL REMAIN UP THROUGH THE DAY TODAY
BEFORE THEY DIMINISH THIS EVENING AND TONIGHT.

ANOTHER GOOD POTENTIAL OF STRONGER WINDS LOOKS POISED TO MOVE IN ON
MON WITH THE STRONGER WINDS AHEAD OF THE COLD FRONT. SMALL CRAFT
ADVISORIES AND BEACH HAZARDS STATEMENTS LOOK LIKELY FOR MON.

&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...NJJ







000
FXUS63 KGRR 300729
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
329 AM EDT SAT AUG 30 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE

.SYNOPSIS...
ISSUED AT 327 AM EDT SAT AUG 30 2014

A LOW PRESSURE SYSTEM TRACKING THROUGH THE NORTHERN GREAT LAKES
WILL DRAG A COLD FRONT THROUGH THE SOUTHWEST LOWER MICHIGAN
TONIGHT. PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING AHEAD OF THE COLD FRONT. IT WILL BE WARM AND
HUMID TODAY TOO. SUNDAY WILL FOR THE MOST PART BE PARTLY CLOUDY
WITH A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. IT WILL
CONTINUE TO BE WARM AND HUMID. A COLD FRONT PUSHING INTO THE AREA
ON LABOR DAY WILL BRING THE RISK FOR SEVERE STORMS IN THE
AFTERNOON. WARM AND HUMID CONDITIONS WILL CONTINUE.


&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014


WE HAVE TWO PERIODS OF CONVECTION TO WATCH IN THE SHORT TERM
FORECAST. THE THUNDERSTORMS AHEAD OF THE WEAK COLD FRONT THAT
COMES THROUGH THE AREA TONIGHT... THEN THE POSSIBLY SEVERE STORMS
ON LABOR DAY AS A STRONG JET STREAM INTERACTS WITH THE COLD FRONT
DURING MAX HEATING.

A QUICK OVERVIEW OF WHAT IS HAPPENING ON THE LARGER SCALE IS THE
SHEARING OUT SOUTHERN STREAM WAVE WE HAVE BEEN WATCHING OVER OVER
A WEEK NOW COMES THROUGH THE AREA TODAY. THE MODELS ALL SHOW THE
327 MB WAVE DEVELOPING A CLOSED UPPER LOW BY MID AFTERNOON. THE
ASSOCIATED DYNAMICS OF THE UPPER JET STREAM AND CORRESPONDING LOW
LEVEL JET WILL BRING THUNDERSTORMS TO THE AREA TODAY. THAT SYSTEM
MOVES OUT OF THE AREA LEAVING A SHORTWAVE RIDGE IN THE AREA
SUNDAY. THIS WILL RESULT IN QUIET WEATHER INTO SUNDAY NIGHT.
FINALLY A STRONG PACIFIC STORM BRINGS A NORTHERN STREAM WAVE INTO
THE AREA ON LABOR DAY. THIS WILL BRING STRONG JET DYNAMICS WITH IT
AND WILL REUSTL IN A STRONG LOW LEVEL RESPONSE TO THE ASSOCIATED
COUPLED JET CORE MOVING THROUGH THROUGH ON LABOR DAY.

AS FOR TODAY...THERE WILL BE TWO PERIODS OF CONVECTION. THE FIRST
WAVE IS ASSOCIATED WITH A INCREASE IN DEEP MOISTURE AND IS
LARGELY THE SYSTEM WARM FRONT COMING THROUGH. THIS HAS A LOW LEVEL
JET ASSOCIATED WITH IT AND THE AXIS OF THAT JET WILL BE FROM BTL
TO MBS BY MID MORNING. THIS WILL HELP DEVELOP STORMS OVER WESTERN
LOWER MICHIGAN THAT WILL MOVE EAST ACROSS THE STATE DURING THE
DAY. THEN THERE IS A SECOND LOW LEVEL JET ASSOCIATE WITH THE MAIN
UPPER WAVE. IT COMES ONTO SOUTHWEST MICHIGAN THIS AFTERNOON AND
INCREASE TO 35 TO 40 KNOTS NEAR LANSING BY 2 PM. THAT WILL DEVELOP
A SECOND AREA OF CONVECTION OVER WESTERN LOWER MICHIGAN THAT WILL
ALSO MOVE EAST BY LATE AFTERNOON. BY THEN MIX LAYER CAPES COULD BE
1500 J/KG SO AND THERE COULD BE AS MUCH AS 30 KNOTS OF EFFECT DEEP
LAYER SHEAR SO SOME STORMS MAY BE STRONG.

ALL OF THAT MOVES OUT LATE THIS EVENING AND SHORTWAVE RIDING
FOLLOWS SUNDAY. HOWEVER THERE IS STILL SOME INSTABILITY EVEN THOUGH
THE MID LEVELS (ABOVE 850 MB) IS RATHER DRY. I ADDED A SMALL
CHANCE OF AFTERNOON THUNDERSTORMS MOSTLY SOUTH OF I-96 IN THE
AFTERNOON FOR THAT.

THE MAIN STORY IS MONDAY WHEN THE UPPER LEVEL WAVE MOVES INTO VERY
UNSTABLE AIR. THE LOW LEVEL JET ON THE GFS IS FOCUSED ON SOUTHWEST
LOWER MICHIGAN IN THE AFTERNOON AND SHOWS OVER 3270 J/KG OF CAPE.
SO THERE IS REAL POTENTIAL FOR SEVERE STORMS.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 327 AM EDT SAT AUG 30 2014

THE MAIN FOCUS OF THE LONG TERM REMAINS ON THE SYSTEM THAT WILL BE
AFFECTING THE AREA DURING THE FIRST PART OF NEXT WEEK. THE FRONT
LOOKS TO START OUT MON EVENING TO OUR WEST YET. THIS WILL KEEP THE
THREAT OF STORMS IN THE FCST...ALTHOUGH THE THREAT OF SEVERE WEATHER
WILL BE DIMINISHING AS DIURNAL INSTABILITY WILL BE ON THE WANE A
BIT.

A RESIDUAL CHC OF SHOWERS AND STORMS WILL BE LEFT IN FOR THE DAY ON
TUE. THE FRONT LOOKS TO SINK JUST SOUTH OF THE AREA AND STALL OUT.
HOW FAR SOUTH IT STALLS IS UNCERTAIN WITH THE GFS A BIT FURTHER
SOUTH...AND THE EURO KEEPING IT CLOSER TO THE AREA. THIS FRONTAL
POSITION WILL BE IMPORTANT AS ANOTHER WAVE LOOKS TO MOVE THROUGH THE
REGION AND COULD BRING ANOTHER ROUND OF RAIN TO THE AREA ON TUE.

THE AREA SHOULD DRY OUT FOR WED WITH A RIDGE OF HIGH PRESSURE
BUILDING INTO THE AREA. THIS RIDGE WILL BE FAIRLY FLAT IN NATURE AND
WILL BE SHORT LIVED. A TROUGH EXPECTED TO COME ONSHORE OVER THE
PACIFIC NW DURING THE TUE TIME FRAME WILL PUSH A FRONTAL SYSTEM SE
INTO THE AREA LATE IN THE WEEK. PCPN CHCS WILL START ON THU AS A
WARM FRONT MOVES THROUGH THE AREA. THE COLD FRONT THEN FOLLOWS FOR
THE DAY ON FRI.


&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 153 AM EDT SAT AUG 30 2014

PCPN/CONVECTION TRENDS ARE THE MAIN CONCERNS FOR THE 06Z FCST
PERIOD. THE DETAILS IN THE CONVECTION TRENDS ARE STILL A BIT
UNCERTAIN THROUGH MOST OF THE PERIOD. WE CAN NOT RULE OUT A POP UP
SHOWER OR EVEN STORM REALLY AT ANY POINT THROUGH ABOUT 01-02Z SUN.

THERE DO LOOK TO BE TWO BETTER OPPORTUNITIES. THE FIRST WILL START
AFFECTING KMKG AROUND 09Z OR SO AND THEN SPREAD TO THE EAST. THIS
WILL LIKELY BE MORE SHOWERS THAN STORMS...SO WE HAVE GONE WITH
VCSH AND A TEMPO GROUP. THE SECOND IS AFTER 18Z THIS AFTERNOON AS
THE CENTER OF THE SYSTEM MOVES IN AND HEATING OF THE DAY STARTS TO
HELP POP SHOWERS AND STORMS.

WE BELIEVE AS THE LOW STARTS TO MOVE EAST OF THE AREA AFTER ABOUT
01-02Z SUN...PCPN WILL END. WE COULD SEE SOME RESIDUAL MVFR CIGS
HOLD IN THEN THROUGH THE END OF THE FCST PERIOD.


&&

.MARINE...
ISSUED AT 327 AM EDT SAT AUG 30 2014

WE WILL BE LEAVING THE MARINE AND BEACH HEADLINES AS IS THIS
MORNING. WINDS ARE UP NEAR SMALL CRAFT ADVISORY CRITERIA AT MANY
LOCATIONS ALONG THE COAST. WAVES ARE A BIT MORE MARGINAL...HOWEVER
THEY SHOULD BUILD A BIT AS THE FLOW GOES FROM OFFSHORE TO MORE
ONSHORE THIS AFTERNOON. WINDS WILL REMAIN UP THROUGH THE DAY TODAY
BEFORE THEY DIMINISH THIS EVENING AND TONIGHT.

ANOTHER GOOD POTENTIAL OF STRONGER WINDS LOOKS POISED TO MOVE IN ON
MON WITH THE STRONGER WINDS AHEAD OF THE COLD FRONT. SMALL CRAFT
ADVISORIES AND BEACH HAZARDS STATEMENTS LOOK LIKELY FOR MON.

&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...NJJ








000
FXUS63 KGRR 300553
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
153 AM EDT SAT AUG 30 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 307 PM EDT FRI AUG 29 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION TONIGHT THROUGH SATURDAY. THIS SYSTEM WILL PRODUCE
AREAS OF SHOWERS AND THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL. A
WEAK AREA OF HIGH PRESSURE WILL TEMPORARILY MOVE IN FOR SUNDAY
LEADING TO MAINLY DRY WEATHER. THE RISK FOR THUNDERSTORMS RETURNS
FOR MONDAY AS A WEAK COLD FRONT TRACKS EASTWARD THROUGH THE STATE.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 307 PM EDT FRI AUG 29 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE TIMING AND
COVERAGE OF ANY SHOWERS AND THUNDERSTORMS. THE UPPER LOW NEAR
KANSAS CITY TRACKS NORTHEAST THROUGH SATURDAY. DEEPER MOISTURE
ARRIVES HERE IN SOUTHWEST LOWER MI DURING THIS TIME AND THE
ATMOSPHERE REMAINS UNSTABLE. SO WITH SOME FORCING...MOISTURE AND
INSTABILITY WE WILL SEE A RISK FOR THUNDERSTORMS INTO SATURDAY
NIGHT. THE LOW LEVEL JET WILL LIKELY FOCUS THE STORMS. AROUND 12Z
SAT WE SEE SOME LOW LEVEL CONVERGENCE ASSOCIATED WITH THE LOW
LEVEL JET THAT IT APPEARS WILL HELP CREATE NUMEROUS SHOWERS AND
THUNDERSTORMS. FOR THAT REASON I FEATURED THE HIGHEST POPS FOR SATURDAY.

WE WILL DRY OUT SAT NIGHT INTO SUNDAY AS THE WAVE OF LOW PRESSURE
PULLS AWAY.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 307 PM EDT FRI AUG 29 2014

ANOTHER COLD FRONT SHOULD BE COMING THROUGH MONDAY NIGHT.  SHOWERS
AND STORMS SHOULD BE ON THE INCREASE THROUGH MONDAY.  THERE IS AN
OUTSIDE CHANCE THAT A FEW STORMS COULD BE SEVERE...BUT MAINLY THIS
APPEARS TO BE A WET SYSTEM WITH PRECIPITABLE WATER VALUES AROUND
1.75 INCHES.  WILL MAINTAIN THE LIKELY POPS...AND EXPAND THEM ACROSS
THE ENTIRE CWA FOR MONDAY.  THE FRONT SEEMS TO HAVE SLOWED DOWN A
BIT ON THE MEDIUM RANGE MODELS...SO HAVE EXTENDED THE CHANCE POPS
INTO TUESDAY.

WE SHOULD HAVE A MOSTLY DRY PERIOD FROM TUESDAY NIGHT THROUGH
THURSDAY AS HIGH PRESSURE DRIFTS THROUGH.  AFTER A SLIGHT COOL DOWN
TUESDAY AND WEDNESDAY...TEMPS SHOULD REBOUND AGAIN FOR THURSDAY AS
RETURN SOUTHERLY FLOW KICKS IN.  THURSDAY SHOULD BE THE WARMEST DAY
OF THE WEEK...IN THE LOWER TO MID 80S.  THEN THERE ARE SOME MODELS
DIFFERENCES IN TIMING...BUT IT APPEARS ANOTHER COLD FRONT ARRIVES
THURSDAY NIGHT OR FRIDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 153 AM EDT SAT AUG 30 2014

PCPN/CONVECTION TRENDS ARE THE MAIN CONCERNS FOR THE 06Z FCST
PERIOD. THE DETAILS IN THE CONVECTION TRENDS ARE STILL A BIT
UNCERTAIN THROUGH MOST OF THE PERIOD. WE CAN NOT RULE OUT A POP UP
SHOWER OR EVEN STORM REALLY AT ANY POINT THROUGH ABOUT 01-02Z SUN.

THERE DO LOOK TO BE TWO BETTER OPPORTUNITIES. THE FIRST WILL START
AFFECTING KMKG AROUND 09Z OR SO AND THEN SPREAD TO THE EAST. THIS
WILL LIKELY BE MORE SHOWERS THAN STORMS...SO WE HAVE GONE WITH
VCSH AND A TEMPO GROUP. THE SECOND IS AFTER 18Z THIS AFTERNOON AS
THE CENTER OF THE SYSTEM MOVES IN AND HEATING OF THE DAY STARTS TO
HELP POP SHOWERS AND STORMS.

WE BELIEVE AS THE LOW STARTS TO MOVE EAST OF THE AREA AFTER ABOUT
01-02Z SUN...PCPN WILL END. WE COULD SEE SOME RESIDUAL MVFR CIGS
HOLD IN THEN THROUGH THE END OF THE FCST PERIOD.

&&

.MARINE...
ISSUED AT 307 PM EDT FRI AUG 29 2014

WITH A LOW LEVEL JET MOVING IN TONIGHT WINDS WILL
INCREASE...ESPECIALLY OVER LAKE MI. IT IS A GOOD SETUP FOR WAVES
OVER 3 FEET AS THE WINDS VEER FROM SOUTHEAST TO SOUTHWEST. THE
LONGER FETCH SUPPORT HIGHEST WAVES GENERALLY NORTH OF HOLLAND.
THE LOW LEVEL JET PULLS OUT LATER SATURDAY. THIS WILL ACT TO
SUPPORT DECREASING WAVE HEIGHTS.


&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 300553
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
153 AM EDT SAT AUG 30 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 307 PM EDT FRI AUG 29 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION TONIGHT THROUGH SATURDAY. THIS SYSTEM WILL PRODUCE
AREAS OF SHOWERS AND THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL. A
WEAK AREA OF HIGH PRESSURE WILL TEMPORARILY MOVE IN FOR SUNDAY
LEADING TO MAINLY DRY WEATHER. THE RISK FOR THUNDERSTORMS RETURNS
FOR MONDAY AS A WEAK COLD FRONT TRACKS EASTWARD THROUGH THE STATE.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 307 PM EDT FRI AUG 29 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE TIMING AND
COVERAGE OF ANY SHOWERS AND THUNDERSTORMS. THE UPPER LOW NEAR
KANSAS CITY TRACKS NORTHEAST THROUGH SATURDAY. DEEPER MOISTURE
ARRIVES HERE IN SOUTHWEST LOWER MI DURING THIS TIME AND THE
ATMOSPHERE REMAINS UNSTABLE. SO WITH SOME FORCING...MOISTURE AND
INSTABILITY WE WILL SEE A RISK FOR THUNDERSTORMS INTO SATURDAY
NIGHT. THE LOW LEVEL JET WILL LIKELY FOCUS THE STORMS. AROUND 12Z
SAT WE SEE SOME LOW LEVEL CONVERGENCE ASSOCIATED WITH THE LOW
LEVEL JET THAT IT APPEARS WILL HELP CREATE NUMEROUS SHOWERS AND
THUNDERSTORMS. FOR THAT REASON I FEATURED THE HIGHEST POPS FOR SATURDAY.

WE WILL DRY OUT SAT NIGHT INTO SUNDAY AS THE WAVE OF LOW PRESSURE
PULLS AWAY.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 307 PM EDT FRI AUG 29 2014

ANOTHER COLD FRONT SHOULD BE COMING THROUGH MONDAY NIGHT.  SHOWERS
AND STORMS SHOULD BE ON THE INCREASE THROUGH MONDAY.  THERE IS AN
OUTSIDE CHANCE THAT A FEW STORMS COULD BE SEVERE...BUT MAINLY THIS
APPEARS TO BE A WET SYSTEM WITH PRECIPITABLE WATER VALUES AROUND
1.75 INCHES.  WILL MAINTAIN THE LIKELY POPS...AND EXPAND THEM ACROSS
THE ENTIRE CWA FOR MONDAY.  THE FRONT SEEMS TO HAVE SLOWED DOWN A
BIT ON THE MEDIUM RANGE MODELS...SO HAVE EXTENDED THE CHANCE POPS
INTO TUESDAY.

WE SHOULD HAVE A MOSTLY DRY PERIOD FROM TUESDAY NIGHT THROUGH
THURSDAY AS HIGH PRESSURE DRIFTS THROUGH.  AFTER A SLIGHT COOL DOWN
TUESDAY AND WEDNESDAY...TEMPS SHOULD REBOUND AGAIN FOR THURSDAY AS
RETURN SOUTHERLY FLOW KICKS IN.  THURSDAY SHOULD BE THE WARMEST DAY
OF THE WEEK...IN THE LOWER TO MID 80S.  THEN THERE ARE SOME MODELS
DIFFERENCES IN TIMING...BUT IT APPEARS ANOTHER COLD FRONT ARRIVES
THURSDAY NIGHT OR FRIDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 153 AM EDT SAT AUG 30 2014

PCPN/CONVECTION TRENDS ARE THE MAIN CONCERNS FOR THE 06Z FCST
PERIOD. THE DETAILS IN THE CONVECTION TRENDS ARE STILL A BIT
UNCERTAIN THROUGH MOST OF THE PERIOD. WE CAN NOT RULE OUT A POP UP
SHOWER OR EVEN STORM REALLY AT ANY POINT THROUGH ABOUT 01-02Z SUN.

THERE DO LOOK TO BE TWO BETTER OPPORTUNITIES. THE FIRST WILL START
AFFECTING KMKG AROUND 09Z OR SO AND THEN SPREAD TO THE EAST. THIS
WILL LIKELY BE MORE SHOWERS THAN STORMS...SO WE HAVE GONE WITH
VCSH AND A TEMPO GROUP. THE SECOND IS AFTER 18Z THIS AFTERNOON AS
THE CENTER OF THE SYSTEM MOVES IN AND HEATING OF THE DAY STARTS TO
HELP POP SHOWERS AND STORMS.

WE BELIEVE AS THE LOW STARTS TO MOVE EAST OF THE AREA AFTER ABOUT
01-02Z SUN...PCPN WILL END. WE COULD SEE SOME RESIDUAL MVFR CIGS
HOLD IN THEN THROUGH THE END OF THE FCST PERIOD.

&&

.MARINE...
ISSUED AT 307 PM EDT FRI AUG 29 2014

WITH A LOW LEVEL JET MOVING IN TONIGHT WINDS WILL
INCREASE...ESPECIALLY OVER LAKE MI. IT IS A GOOD SETUP FOR WAVES
OVER 3 FEET AS THE WINDS VEER FROM SOUTHEAST TO SOUTHWEST. THE
LONGER FETCH SUPPORT HIGHEST WAVES GENERALLY NORTH OF HOLLAND.
THE LOW LEVEL JET PULLS OUT LATER SATURDAY. THIS WILL ACT TO
SUPPORT DECREASING WAVE HEIGHTS.


&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ844>849.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...NJJ
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 300001
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
801 PM EDT FRI AUG 29 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 307 PM EDT FRI AUG 29 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION TONIGHT THROUGH SATURDAY. THIS SYSTEM WILL PRODUCE
AREAS OF SHOWERS AND THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL. A
WEAK AREA OF HIGH PRESSURE WILL TEMPORARILY MOVE IN FOR SUNDAY
LEADING TO MAINLY DRY WEATHER. THE RISK FOR THUNDERSTORMS RETURNS
FOR MONDAY AS A WEAK COLD FRONT TRACKS EASTWARD THROUGH THE STATE.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 307 PM EDT FRI AUG 29 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE TIMING AND
COVERAGE OF ANY SHOWERS AND THUNDERSTORMS. THE UPPER LOW NEAR
KANSAS CITY TRACKS NORTHEAST THROUGH SATURDAY. DEEPER MOISTURE
ARRIVES HERE IN SOUTHWEST LOWER MI DURING THIS TIME AND THE
ATMOSPHERE REMAINS UNSTABLE. SO WITH SOME FORCING...MOISTURE AND
INSTABILITY WE WILL SEE A RISK FOR THUNDERSTORMS INTO SATURDAY
NIGHT. THE LOW LEVEL JET WILL LIKELY FOCUS THE STORMS. AROUND 12Z
SAT WE SEE SOME LOW LEVEL CONVERGENCE ASSOCIATED WITH THE LOW
LEVEL JET THAT IT APPEARS WILL HELP CREATE NUMEROUS SHOWERS AND
THUNDERSTORMS. FOR THAT REASON I FEATURED THE HIGHEST POPS FOR SATURDAY.

WE WILL DRY OUT SAT NIGHT INTO SUNDAY AS THE WAVE OF LOW PRESSURE
PULLS AWAY.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 307 PM EDT FRI AUG 29 2014

ANOTHER COLD FRONT SHOULD BE COMING THROUGH MONDAY NIGHT.  SHOWERS
AND STORMS SHOULD BE ON THE INCREASE THROUGH MONDAY.  THERE IS AN
OUTSIDE CHANCE THAT A FEW STORMS COULD BE SEVERE...BUT MAINLY THIS
APPEARS TO BE A WET SYSTEM WITH PRECIPITABLE WATER VALUES AROUND
1.75 INCHES.  WILL MAINTAIN THE LIKELY POPS...AND EXPAND THEM ACROSS
THE ENTIRE CWA FOR MONDAY.  THE FRONT SEEMS TO HAVE SLOWED DOWN A
BIT ON THE MEDIUM RANGE MODELS...SO HAVE EXTENDED THE CHANCE POPS
INTO TUESDAY.

WE SHOULD HAVE A MOSTLY DRY PERIOD FROM TUESDAY NIGHT THROUGH
THURSDAY AS HIGH PRESSURE DRIFTS THROUGH.  AFTER A SLIGHT COOL DOWN
TUESDAY AND WEDNESDAY...TEMPS SHOULD REBOUND AGAIN FOR THURSDAY AS
RETURN SOUTHERLY FLOW KICKS IN.  THURSDAY SHOULD BE THE WARMEST DAY
OF THE WEEK...IN THE LOWER TO MID 80S.  THEN THERE ARE SOME MODELS
DIFFERENCES IN TIMING...BUT IT APPEARS ANOTHER COLD FRONT ARRIVES
THURSDAY NIGHT OR FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 800 PM EDT FRI AUG 29 2014

EXPECTING MAINLY VFR CONDITIONS THE NEXT 24 HOURS...OUTSIDE OF
SHOWERS/THUNDERSTORMS. IT WILL TURN A BIT BREEZY ON SATURDAY
MORNING (AROUND 12Z) WITH SOUTH-SOUTHWEST WINDS OF 12-25 KNOTS.

AS FOR TONIGHT...SOME SCATTERED SHOWERS WILL BE AROUND THIS
EVENING...BUT NOT EXPECTING ANYTHING WIDESPREAD. HAVE COVERED THE
THREAT FOR SHOWERS WITH VCSH FOR NOW. OVERNIGHT...EXPECTING THERE
MAY BE AN UPTICK IN SHOWER AND THUNDERSTORM DEVELOPMENT AND HAVE
VCTS WORDING IN THE TAFS FROM 06Z TO 12Z.

A LULL IN THE ACTIVITY SHOULD OCCUR SATURDAY MORNING AFTER THE
OVERNIGHT ACTIVITY MOVES THROUGH. ANOTHER INCREASE IN ACTIVITY
SHOULD OCCUR SATURDAY AFTERNOON AND ONCE AGAIN HAVE VCTS IN THE
TAFS FROM 18Z TO 00Z.

&&

.MARINE...
ISSUED AT 307 PM EDT FRI AUG 29 2014

WITH A LOW LEVEL JET MOVING IN TONIGHT WINDS WILL
INCREASE...ESPECIALLY OVER LAKE MI. IT IS A GOOD SETUP FOR WAVES
OVER 3 FEET AS THE WINDS VEER FROM SOUTHEAST TO SOUTHWEST. THE
LONGER FETCH SUPPORT HIGHEST WAVES GENERALLY NORTH OF HOLLAND.
THE LOW LEVEL JET PULLS OUT LATER SATURDAY. THIS WILL ACT TO
SUPPORT DECREASING WAVE HEIGHTS.


&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH SATURDAY EVENING FOR MIZ037-043-
     050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR LMZ848-849.

     SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR LMZ844>847.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...DUKE
HYDROLOGY...MJS
MARINE...MJS







000
FXUS63 KGRR 300001
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
801 PM EDT FRI AUG 29 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 307 PM EDT FRI AUG 29 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION TONIGHT THROUGH SATURDAY. THIS SYSTEM WILL PRODUCE
AREAS OF SHOWERS AND THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL. A
WEAK AREA OF HIGH PRESSURE WILL TEMPORARILY MOVE IN FOR SUNDAY
LEADING TO MAINLY DRY WEATHER. THE RISK FOR THUNDERSTORMS RETURNS
FOR MONDAY AS A WEAK COLD FRONT TRACKS EASTWARD THROUGH THE STATE.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 307 PM EDT FRI AUG 29 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE TIMING AND
COVERAGE OF ANY SHOWERS AND THUNDERSTORMS. THE UPPER LOW NEAR
KANSAS CITY TRACKS NORTHEAST THROUGH SATURDAY. DEEPER MOISTURE
ARRIVES HERE IN SOUTHWEST LOWER MI DURING THIS TIME AND THE
ATMOSPHERE REMAINS UNSTABLE. SO WITH SOME FORCING...MOISTURE AND
INSTABILITY WE WILL SEE A RISK FOR THUNDERSTORMS INTO SATURDAY
NIGHT. THE LOW LEVEL JET WILL LIKELY FOCUS THE STORMS. AROUND 12Z
SAT WE SEE SOME LOW LEVEL CONVERGENCE ASSOCIATED WITH THE LOW
LEVEL JET THAT IT APPEARS WILL HELP CREATE NUMEROUS SHOWERS AND
THUNDERSTORMS. FOR THAT REASON I FEATURED THE HIGHEST POPS FOR SATURDAY.

WE WILL DRY OUT SAT NIGHT INTO SUNDAY AS THE WAVE OF LOW PRESSURE
PULLS AWAY.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 307 PM EDT FRI AUG 29 2014

ANOTHER COLD FRONT SHOULD BE COMING THROUGH MONDAY NIGHT.  SHOWERS
AND STORMS SHOULD BE ON THE INCREASE THROUGH MONDAY.  THERE IS AN
OUTSIDE CHANCE THAT A FEW STORMS COULD BE SEVERE...BUT MAINLY THIS
APPEARS TO BE A WET SYSTEM WITH PRECIPITABLE WATER VALUES AROUND
1.75 INCHES.  WILL MAINTAIN THE LIKELY POPS...AND EXPAND THEM ACROSS
THE ENTIRE CWA FOR MONDAY.  THE FRONT SEEMS TO HAVE SLOWED DOWN A
BIT ON THE MEDIUM RANGE MODELS...SO HAVE EXTENDED THE CHANCE POPS
INTO TUESDAY.

WE SHOULD HAVE A MOSTLY DRY PERIOD FROM TUESDAY NIGHT THROUGH
THURSDAY AS HIGH PRESSURE DRIFTS THROUGH.  AFTER A SLIGHT COOL DOWN
TUESDAY AND WEDNESDAY...TEMPS SHOULD REBOUND AGAIN FOR THURSDAY AS
RETURN SOUTHERLY FLOW KICKS IN.  THURSDAY SHOULD BE THE WARMEST DAY
OF THE WEEK...IN THE LOWER TO MID 80S.  THEN THERE ARE SOME MODELS
DIFFERENCES IN TIMING...BUT IT APPEARS ANOTHER COLD FRONT ARRIVES
THURSDAY NIGHT OR FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 800 PM EDT FRI AUG 29 2014

EXPECTING MAINLY VFR CONDITIONS THE NEXT 24 HOURS...OUTSIDE OF
SHOWERS/THUNDERSTORMS. IT WILL TURN A BIT BREEZY ON SATURDAY
MORNING (AROUND 12Z) WITH SOUTH-SOUTHWEST WINDS OF 12-25 KNOTS.

AS FOR TONIGHT...SOME SCATTERED SHOWERS WILL BE AROUND THIS
EVENING...BUT NOT EXPECTING ANYTHING WIDESPREAD. HAVE COVERED THE
THREAT FOR SHOWERS WITH VCSH FOR NOW. OVERNIGHT...EXPECTING THERE
MAY BE AN UPTICK IN SHOWER AND THUNDERSTORM DEVELOPMENT AND HAVE
VCTS WORDING IN THE TAFS FROM 06Z TO 12Z.

A LULL IN THE ACTIVITY SHOULD OCCUR SATURDAY MORNING AFTER THE
OVERNIGHT ACTIVITY MOVES THROUGH. ANOTHER INCREASE IN ACTIVITY
SHOULD OCCUR SATURDAY AFTERNOON AND ONCE AGAIN HAVE VCTS IN THE
TAFS FROM 18Z TO 00Z.

&&

.MARINE...
ISSUED AT 307 PM EDT FRI AUG 29 2014

WITH A LOW LEVEL JET MOVING IN TONIGHT WINDS WILL
INCREASE...ESPECIALLY OVER LAKE MI. IT IS A GOOD SETUP FOR WAVES
OVER 3 FEET AS THE WINDS VEER FROM SOUTHEAST TO SOUTHWEST. THE
LONGER FETCH SUPPORT HIGHEST WAVES GENERALLY NORTH OF HOLLAND.
THE LOW LEVEL JET PULLS OUT LATER SATURDAY. THIS WILL ACT TO
SUPPORT DECREASING WAVE HEIGHTS.


&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH SATURDAY EVENING FOR MIZ037-043-
     050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR LMZ848-849.

     SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR LMZ844>847.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...DUKE
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 291929
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
329 PM EDT FRI AUG 29 2014

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE

.SYNOPSIS...
ISSUED AT 307 PM EDT FRI AUG 29 2014

AN AREA OF LOW PRESSURE WILL TRACK NORTHEAST THROUGH THE GREAT
LAKES REGION TONIGHT THROUGH SATURDAY. THIS SYSTEM WILL PRODUCE
AREAS OF SHOWERS AND THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL. A
WEAK AREA OF HIGH PRESSURE WILL TEMPORARILY MOVE IN FOR SUNDAY
LEADING TO MAINLY DRY WEATHER. THE RISK FOR THUNDERSTORMS RETURNS
FOR MONDAY AS A WEAK COLD FRONT TRACKS EASTWARD THROUGH THE STATE.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 307 PM EDT FRI AUG 29 2014

THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE TIMING AND
COVERAGE OF ANY SHOWERS AND THUNDERSTORMS. THE UPPER LOW NEAR
KANSAS CITY TRACKS NORTHEAST THROUGH SATURDAY. DEEPER MOISTURE
ARRIVES HERE IN SOUTHWEST LOWER MI DURING THIS TIME AND THE
ATMOSPHERE REMAINS UNSTABLE. SO WITH SOME FORCING...MOISTURE AND
INSTABILITY WE WILL SEE A RISK FOR THUNDERSTORMS INTO SATURDAY
NIGHT. THE LOW LEVEL JET WILL LIKELY FOCUS THE STORMS. AROUND 12Z
SAT WE SEE SOME LOW LEVEL CONVERGENCE ASSOCIATED WITH THE LOW
LEVEL JET THAT IT APPEARS WILL HELP CREATE NUMEROUS SHOWERS AND
THUNDERSTORMS. FOR THAT REASON I FEATURED THE HIGHEST POPS FOR SATURDAY.

WE WILL DRY OUT SAT NIGHT INTO SUNDAY AS THE WAVE OF LOW PRESSURE
PULLS AWAY.





.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 307 PM EDT FRI AUG 29 2014

ANOTHER COLD FRONT SHOULD BE COMING THROUGH MONDAY NIGHT.  SHOWERS
AND STORMS SHOULD BE ON THE INCREASE THROUGH MONDAY.  THERE IS AN
OUTSIDE CHANCE THAT A FEW STORMS COULD BE SEVERE...BUT MAINLY THIS
APPEARS TO BE A WET SYSTEM WITH PRECIPITABLE WATER VALUES AROUND
1.75 INCHES.  WILL MAINTAIN THE LIKELY POPS...AND EXPAND THEM ACROSS
THE ENTIRE CWA FOR MONDAY.  THE FRONT SEEMS TO HAVE SLOWED DOWN A
BIT ON THE MEDIUM RANGE MODELS...SO HAVE EXTENDED THE CHANCE POPS
INTO TUESDAY.

WE SHOULD HAVE A MOSTLY DRY PERIOD FROM TUESDAY NIGHT THROUGH
THURSDAY AS HIGH PRESSURE DRIFTS THROUGH.  AFTER A SLIGHT COOL DOWN
TUESDAY AND WEDNESDAY...TEMPS SHOULD REBOUND AGAIN FOR THURSDAY AS
RETURN SOUTHERLY FLOW KICKS IN.  THURSDAY SHOULD BE THE WARMEST DAY
OF THE WEEK...IN THE LOWER TO MID 80S.  THEN THERE ARE SOME MODELS
DIFFERENCES IN TIMING...BUT IT APPEARS ANOTHER COLD FRONT ARRIVES
THURSDAY NIGHT OR FRIDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 153 PM EDT FRI AUG 29 2014

WIDELY SCATTERED THUNDERSTORMS CAN NOT BE COMPLETED RULED OUT ANY
TIME OVER THE NEXT 24 HOURS...HOWEVER I ATTEMPTED TO SHOW WHEN
STORMS WOULD BE THE MOST LIKELY WITHIN THE 18Z TAFS.

INSTABILITY WILL BUILD THROUGH THIS AFTERNOON...HOWEVER THERE IS
NOT A FOCUSED TRIGGER TO START ANYTHING SIGNIFICANT...SO LEFT
STORMS OUT OF THE TAFS UNTIL AFTER 01Z...HOWEVER AN ISOLATED
STORM IS POSSIBLE PRIOR TO THAT. THERE IS A LOW LEVEL JET THAT
DEVELOPS THIS EVENING AND MOVES IN TOWARD SOUTHERN LAKE MICHIGAN.
I HAVE STORMS IN THE TAFS AT AZO AND BTL...BUT FURTHER NORTH AND
EAST ANY STORMS SHOULD WEAKEN...SO ONLY HAVE SHOWERS ELSEWHERE.
ANY STORMS SHOULD DIMINISH AFTER MIDNIGHT AS THE INSTABILITY
LESSENS.

ANOTHER ROUND OF STORMS WILL BECOME POSSIBLE AGAIN THROUGH
MID/LATE SATURDAY MORNING AND INTO EARLY AFTERNOON ACROSS THE
ENTIRE AREA AS INSTABILITY SHOULD INCREASE AGAIN ALONG WITH A
MORE FAVORABLE PUSH OF MOISTURE.

VFR WITH PATCHY MVFR IS EXPECTED OVER THE NEXT 24 HOURS OUTSIDE OF
ANY STORMS.


&&

.MARINE...
ISSUED AT 307 PM EDT FRI AUG 29 2014

WITH A LOW LEVEL JET MOVING IN TONIGHT WINDS WILL
INCREASE...ESPECIALLY OVER LAKE MI. IT IS A GOOD SETUP FOR WAVES
OVER 3 FEET AS THE WINDS VEER FROM SOUTHEAST TO SOUTHWEST. THE
LONGER FETCH SUPPORT HIGHEST WAVES GENERALLY NORTH OF HOLLAND.
THE LOW LEVEL JET PULLS OUT LATER SATURDAY. THIS WILL ACT TO
SUPPORT DECREASING WAVE HEIGHTS.

&&

.HYDROLOGY...
ISSUED AT 307 PM EDT FRI AUG 29 2014

HEAVY RAIN IS A RISK THROUGH SATURDAY. VERY MOIST AIRMASS WILL ADVECT
INTO MI AS PWAT VALUES GENERALLY CLIMB ABOVE 1.5 INCHES. GIVEN THE
LACK OF DIRECTIONAL SHEAR...WE COULD SEE SOME TRAINING WHICH MAY
LEAD TO THE STORMS PERSISTING. IF THIS ENDS UP OCCURRING...SOME
LOCATIONS COULD EASILY SEE OVER 2 INCHES OF RAIN.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM 8 PM EDT THIS EVENING THROUGH
     SATURDAY EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR LMZ848-849.

     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 11 PM EDT
     SATURDAY FOR LMZ844>847.

&&

$$

SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...JK
HYDROLOGY...MJS
MARINE...MJS








000
FXUS63 KGRR 291753
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
153 PM EDT FRI AUG 29 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 325 AM EDT FRI AUG 29 2014

SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE TODAY AS A WARM FRONT
MOVES THROUGH THE AREA. MORE WIDESPREAD THUNDERSTORM ACTIVITY IS
EXPECTED SATURDAY AHEAD OF THE COLD FRONT...WHICH COMES THROUGH
EARLY SUNDAY MORNING. BEHIND THE COLD FRONT ON SUNDAY EXPECT
PARTIAL CLEARING BY AFTERNOON. THEN A STRONG COLD FRONT WILL BRING
THE RISK OF ADDI TONAL STORMS MONDAY.

&&

.UPDATE...
ISSUED AT 1130 AM EDT FRI AUG 29 2014

LOWERED TEMPERATURES SLIGHTLY AND ADDED A RISK FOR THUNDERSTORMS
THIS AFTERNOON. ELEVATED INSTABILITY MOVES IN FOR THE AFTERNOON.
ALSO RADAR SHOWS CONVECTION CROSSING THE LAKE. CLOUDS WILL LIKELY
LIMIT HIGH TEMPERATURES TODAY. WARMEST READINGS MAY BE LATER IN
THE AFTERNOON WHEN WE WILL POTENTIALLY SEE MORE SUN.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 325 AM EDT FRI AUG 29 2014

WE ARE TRACKING SHOWERS AND THUNDERSTORMS TODAY THROUGH SATURDAY
NIGHT. WHILE THERE COULD BE SOME SHOWERS AND ISOLATED THUNDERSTORMS
AROUND TODAY....IT WOULD SEEM OUR BEST POTENTIAL FOR WIDESPREAD
CONVECTION IS SATURDAY AS THE UPPER WAVE MOVES THROUGH.

THE BIG PICTURE FINDS A OPENING UP SOUTHERN STREAM CLOSED UPPER
LOW MOVING EAST AS IT SHEARS OUT AND MOVES OVER MICHIGAN DURING
THE DAY TIME SATURDAY. THE MODELS AS NEARLY ALWAYS WEAK THESE
FEATURE TO FAST SO I WOULD EXPECT STRONG DYNAMICS SATURDAY THEN
ANY OF THE MODELS CURRENTLY WOULD SUGGEST. IN ANY EVENT AS THIS
UPPER WAVE HEADS TOWARD MICHIGAN IT DISPLACES A SHORTWAVE RIDGE
CURRENTLY IN PLACE OVER MICHIGAN. THAT RESULTS IN A SURGE OF MID
LEVEL MOISTURE THAT SHOULD LEAD TO SOME SHOWER AND THUNDERSTORM
ACTIVITY OVER THE WESTERN AND NORTHER SECTIONS OF THE CWA TODAY.
THEN THE PASSAGE OF THE MAIN SYSTEM SATURDAY WILL BRING MORE
WIDESPREAD CONVECTION TO THE AREA.

LOOKING AT THE 1000/850 MOISTURE TRANSPORT VECTORS FROM THE
GFS...NAM AND ECMWF FOR TODAY THE STORY THEY TELL IS SIMILAR TO
WHAT THEY SHOWED YESTERDAY AND THE DAY BEFORE THAT. FOR THE MOST
PART THE BEST MOISTURE TRANSPORT WILL BE NORTH AND WEST OF THE GRR
CWA TODAY. THE LOW LEVEL JET AXIS IS WEST OF MICHIGAN EARLY THIS
MORNING AND IS MOSTLY OVER NORTHERN LOWER AND UPPER MICHIGAN THIS
AFTERNOON INTO TONIGHT. ALSO THE INSTABILITY IS RATHER LIMITED AND
WHAT THERE IS OF IT IS MOSTLY OVER WESTERN SECTIONS OF LOWER
MICHIGAN INTO THIS AFTERNOON. THE SHORTWAVE RIDGE AHEAD OF THE
UPPER WAVE HAS BROUGHT TO WARM OF AIR ABOVE 700 MB SO THAT
VERTICAL TOTALS ARE MARGINAL AT BEST FOR THUNDERSTORMS TODAY. WHAT
BRING THE SHOWERS TO THE AREA TODAY IS A SURGE OF MID LEVEL
MOISTURE AS THE PRECIPITABLE WATER SURGES FROM UNDER A SEVEN TENTS
OF AN INCH EARLY THIS MORNING TO ABOVE ONE AND THREE QUARTER
INCHES OVER MOST OF THE CWA BY NOON. THE FOCUS OF THIS WILL BE ON
THE WARM FRONT NEAR THE AXIS OF THE LOW LEVEL JET. THAT MEANS MOST
OF THE CONVECTION WILL BE NORTH AND WEST OF THE GRR CWA TODAY.

SATURDAY IS WHEN THE MAIN UPPER WAVE MOVES THROUGH THE AREA AND
THERE IS WORKABLE LOW LEVEL JET IN THE AREA AND SOME UPPER LEVEL
JET SUPPORT SO WE SHOULD HAVE WIDESPREAD SHOWERS AND A FEW NON
SEVERE THUNDERSTORMS (CAPE IS LIMITED AND DEEP LAYER SHEAR IS WEAK
TOO).

ALL OF THIS MOVES OUT SATURDAY NIGHT AND SUNDAY FINES US WITH
SHORT WAVER RIDING. SO I EXPECT CLEARING TO OCCUR DURING THE DAY
SUNDAY AS DRY AIR MOVES IN FROM THE NORTHWEST.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 325 AM
EDT FRI AUG 29 2014

THE MAIN WEATHER IN THE LONG TERM WILL BE FOCUSED ON THE CONVECTION
CHCS EARLY ON IN THE PERIOD WITH A SYSTEM THAT WILL BE MOVING
THROUGH THE AREA. THE AREA WILL SEE A BREAK IN THE WEATHER FOR SUN
NIGHT IN THE WAKE OF THE DEPARTING SYSTEM FROM SAT/SAT NIGHT...AND
WELL OUT AHEAD OF THE SYSTEM POISED TO MOVE THROUGH THE AREA ON MON.

THE BREAK WILL BE A SHORT ONE AS THE STORM CHCS WILL BE INCREASING
ON MON MORNING AND LASTING INTO MON EVENING. SHORT WAVE ENERGY
EXPECTED TO COME ONSHORE ACROSS OREGON ON SAT WILL TRAVERSE THE
COUNTRY OVER THE HOLIDAY WEEKEND AND WILL BE LIFTING INTO ONTARIO BY
MON AFTERNOON. THE SHORT WAVE REMAINS MAINLY NORTH OF THE AREA.
HOWEVER THE ASSOCIATED LLJ AND STRONG MOISTURE TRANSPORT DOES MOVE
RIGHT INTO THE AREA MON. WE ENVISION A RESIDUAL LINE OF SHOWERS/
STORMS COMING INTO THE AREA FROM THE WEST ON MON...AND STRENGTHENING
AS IT ENCOUNTERS AN INCREASINGLY UNSTABLE AIR MASS WITH DIURNAL
HEATING THAT TAKES PLACE.

WE CAN NOT RULE SOME OF THE STORMS BECOMING SEVERE MON. DEEP LAYER
SHEAR WILL BE ON THE INCREASE WITH THE UPPER JET NEARBY. LI/S ARE
EXPECTED TO DROP DOWN AROUND -6C WITH CAPES APPROACHING OVER 1500
J/KG. THE LLJ OVERHEAD WILL INCREASE THE 0-3 KM SHEAR WHICH WILL
HELP THE CAUSE. THE LIMITATIONS OF POSSIBLE SEVERE WEATHER WOULD BE
LIMITED INSTABILITY IF NOT MUCH HEATING CAN TAKE PLACE...AND NOT
IDEAL UPPER JET DYNAMICS OVERHEAD.

MOST OF THE REST OF THE WEEK SHOULD BE RATHER QUIET AND SEASONABLE
FOR THE AREA. SOME RESIDUAL CHCS OF PCPN WILL HOLD ON TUE UNTIL THE
SECONDARY SHORT WAVE MOVES THROUGH. AFTER THAT...WE GET INTO A
NEARLY ZONAL FLOW WITH LOWER MICHIGAN JUST DOWNSTREAM OF SOME
RIDGING.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 153 PM EDT FRI AUG 29 2014

WIDELY SCATTERED THUNDERSTORMS CAN NOT BE COMPLETED RULED OUT ANY
TIME OVER THE NEXT 24 HOURS...HOWEVER I ATTEMPTED TO SHOW WHEN
STORMS WOULD BE THE MOST LIKELY WITHIN THE 18Z TAFS.

INSTABILITY WILL BUILD THROUGH THIS AFTERNOON...HOWEVER THERE IS
NOT A FOCUSED TRIGGER TO START ANYTHING SIGNIFICANT...SO LEFT
STORMS OUT OF THE TAFS UNTIL AFTER 01Z...HOWEVER AN ISOLATED
STORM IS POSSIBLE PRIOR TO THAT. THERE IS A LOW LEVEL JET THAT
DEVELOPS THIS EVENING AND MOVES IN TOWARD SOUTHERN LAKE MICHIGAN.
I HAVE STORMS IN THE TAFS AT AZO AND BTL...BUT FURTHER NORTH AND
EAST ANY STORMS SHOULD WEAKEN...SO ONLY HAVE SHOWERS ELSEWHERE.
ANY STORMS SHOULD DIMINISH AFTER MIDNIGHT AS THE INSTABILITY
LESSENS.

ANOTHER ROUND OF STORMS WILL BECOME POSSIBLE AGAIN THROUGH
MID/LATE SATURDAY MORNING AND INTO EARLY AFTERNOON ACROSS THE
ENTIRE AREA AS INSTABILITY SHOULD INCREASE AGAIN ALONG WITH A
MORE FAVORABLE PUSH OF MOISTURE.

VFR WITH PATCHY MVFR IS EXPECTED OVER THE NEXT 24 HOURS OUTSIDE OF
ANY STORMS.

&&

.MARINE...
ISSUED AT 1130 AM EDT FRI AUG 29 2014

KEPT THE HAZARDS GOING. SOUTHEAST WINDS BECOME MORE SOUTHERLY AND
INCREASE. THIS SHOULD RESULT IN WAVES POTENTIALLY CLIMBING ABOVE 4 FT.


&&

.HYDROLOGY...
ISSUED AT 328 PM EDT THU AUG 28 2014

THE HEAVY RAIN THREAT APPEARS TO BE LIMITED TO THE MUSKEGON AND
PERE MARQUETTE BASINS AS AN INCH OF QPF CAN BE EXPECTED THERE BY
SUNDAY MORNING...WHICH WOULD RESULT IN RISES BY EARLY NEXT WEEK.
MUCH LESS RAIN IS EXPECTED IN THE GRAND AND KALAMAZOO RIVER
BASINS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM 8 PM EDT THIS EVENING THROUGH
     SATURDAY EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR LMZ848-849.

     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 11 PM EDT
     SATURDAY FOR LMZ844>847.

&&

$$

UPDATE...MJS
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...JK
HYDROLOGY...OSTUNO
MARINE...MJS







000
FXUS63 KGRR 291753
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
153 PM EDT FRI AUG 29 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 325 AM EDT FRI AUG 29 2014

SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE TODAY AS A WARM FRONT
MOVES THROUGH THE AREA. MORE WIDESPREAD THUNDERSTORM ACTIVITY IS
EXPECTED SATURDAY AHEAD OF THE COLD FRONT...WHICH COMES THROUGH
EARLY SUNDAY MORNING. BEHIND THE COLD FRONT ON SUNDAY EXPECT
PARTIAL CLEARING BY AFTERNOON. THEN A STRONG COLD FRONT WILL BRING
THE RISK OF ADDI TONAL STORMS MONDAY.

&&

.UPDATE...
ISSUED AT 1130 AM EDT FRI AUG 29 2014

LOWERED TEMPERATURES SLIGHTLY AND ADDED A RISK FOR THUNDERSTORMS
THIS AFTERNOON. ELEVATED INSTABILITY MOVES IN FOR THE AFTERNOON.
ALSO RADAR SHOWS CONVECTION CROSSING THE LAKE. CLOUDS WILL LIKELY
LIMIT HIGH TEMPERATURES TODAY. WARMEST READINGS MAY BE LATER IN
THE AFTERNOON WHEN WE WILL POTENTIALLY SEE MORE SUN.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 325 AM EDT FRI AUG 29 2014

WE ARE TRACKING SHOWERS AND THUNDERSTORMS TODAY THROUGH SATURDAY
NIGHT. WHILE THERE COULD BE SOME SHOWERS AND ISOLATED THUNDERSTORMS
AROUND TODAY....IT WOULD SEEM OUR BEST POTENTIAL FOR WIDESPREAD
CONVECTION IS SATURDAY AS THE UPPER WAVE MOVES THROUGH.

THE BIG PICTURE FINDS A OPENING UP SOUTHERN STREAM CLOSED UPPER
LOW MOVING EAST AS IT SHEARS OUT AND MOVES OVER MICHIGAN DURING
THE DAY TIME SATURDAY. THE MODELS AS NEARLY ALWAYS WEAK THESE
FEATURE TO FAST SO I WOULD EXPECT STRONG DYNAMICS SATURDAY THEN
ANY OF THE MODELS CURRENTLY WOULD SUGGEST. IN ANY EVENT AS THIS
UPPER WAVE HEADS TOWARD MICHIGAN IT DISPLACES A SHORTWAVE RIDGE
CURRENTLY IN PLACE OVER MICHIGAN. THAT RESULTS IN A SURGE OF MID
LEVEL MOISTURE THAT SHOULD LEAD TO SOME SHOWER AND THUNDERSTORM
ACTIVITY OVER THE WESTERN AND NORTHER SECTIONS OF THE CWA TODAY.
THEN THE PASSAGE OF THE MAIN SYSTEM SATURDAY WILL BRING MORE
WIDESPREAD CONVECTION TO THE AREA.

LOOKING AT THE 1000/850 MOISTURE TRANSPORT VECTORS FROM THE
GFS...NAM AND ECMWF FOR TODAY THE STORY THEY TELL IS SIMILAR TO
WHAT THEY SHOWED YESTERDAY AND THE DAY BEFORE THAT. FOR THE MOST
PART THE BEST MOISTURE TRANSPORT WILL BE NORTH AND WEST OF THE GRR
CWA TODAY. THE LOW LEVEL JET AXIS IS WEST OF MICHIGAN EARLY THIS
MORNING AND IS MOSTLY OVER NORTHERN LOWER AND UPPER MICHIGAN THIS
AFTERNOON INTO TONIGHT. ALSO THE INSTABILITY IS RATHER LIMITED AND
WHAT THERE IS OF IT IS MOSTLY OVER WESTERN SECTIONS OF LOWER
MICHIGAN INTO THIS AFTERNOON. THE SHORTWAVE RIDGE AHEAD OF THE
UPPER WAVE HAS BROUGHT TO WARM OF AIR ABOVE 700 MB SO THAT
VERTICAL TOTALS ARE MARGINAL AT BEST FOR THUNDERSTORMS TODAY. WHAT
BRING THE SHOWERS TO THE AREA TODAY IS A SURGE OF MID LEVEL
MOISTURE AS THE PRECIPITABLE WATER SURGES FROM UNDER A SEVEN TENTS
OF AN INCH EARLY THIS MORNING TO ABOVE ONE AND THREE QUARTER
INCHES OVER MOST OF THE CWA BY NOON. THE FOCUS OF THIS WILL BE ON
THE WARM FRONT NEAR THE AXIS OF THE LOW LEVEL JET. THAT MEANS MOST
OF THE CONVECTION WILL BE NORTH AND WEST OF THE GRR CWA TODAY.

SATURDAY IS WHEN THE MAIN UPPER WAVE MOVES THROUGH THE AREA AND
THERE IS WORKABLE LOW LEVEL JET IN THE AREA AND SOME UPPER LEVEL
JET SUPPORT SO WE SHOULD HAVE WIDESPREAD SHOWERS AND A FEW NON
SEVERE THUNDERSTORMS (CAPE IS LIMITED AND DEEP LAYER SHEAR IS WEAK
TOO).

ALL OF THIS MOVES OUT SATURDAY NIGHT AND SUNDAY FINES US WITH
SHORT WAVER RIDING. SO I EXPECT CLEARING TO OCCUR DURING THE DAY
SUNDAY AS DRY AIR MOVES IN FROM THE NORTHWEST.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 325 AM
EDT FRI AUG 29 2014

THE MAIN WEATHER IN THE LONG TERM WILL BE FOCUSED ON THE CONVECTION
CHCS EARLY ON IN THE PERIOD WITH A SYSTEM THAT WILL BE MOVING
THROUGH THE AREA. THE AREA WILL SEE A BREAK IN THE WEATHER FOR SUN
NIGHT IN THE WAKE OF THE DEPARTING SYSTEM FROM SAT/SAT NIGHT...AND
WELL OUT AHEAD OF THE SYSTEM POISED TO MOVE THROUGH THE AREA ON MON.

THE BREAK WILL BE A SHORT ONE AS THE STORM CHCS WILL BE INCREASING
ON MON MORNING AND LASTING INTO MON EVENING. SHORT WAVE ENERGY
EXPECTED TO COME ONSHORE ACROSS OREGON ON SAT WILL TRAVERSE THE
COUNTRY OVER THE HOLIDAY WEEKEND AND WILL BE LIFTING INTO ONTARIO BY
MON AFTERNOON. THE SHORT WAVE REMAINS MAINLY NORTH OF THE AREA.
HOWEVER THE ASSOCIATED LLJ AND STRONG MOISTURE TRANSPORT DOES MOVE
RIGHT INTO THE AREA MON. WE ENVISION A RESIDUAL LINE OF SHOWERS/
STORMS COMING INTO THE AREA FROM THE WEST ON MON...AND STRENGTHENING
AS IT ENCOUNTERS AN INCREASINGLY UNSTABLE AIR MASS WITH DIURNAL
HEATING THAT TAKES PLACE.

WE CAN NOT RULE SOME OF THE STORMS BECOMING SEVERE MON. DEEP LAYER
SHEAR WILL BE ON THE INCREASE WITH THE UPPER JET NEARBY. LI/S ARE
EXPECTED TO DROP DOWN AROUND -6C WITH CAPES APPROACHING OVER 1500
J/KG. THE LLJ OVERHEAD WILL INCREASE THE 0-3 KM SHEAR WHICH WILL
HELP THE CAUSE. THE LIMITATIONS OF POSSIBLE SEVERE WEATHER WOULD BE
LIMITED INSTABILITY IF NOT MUCH HEATING CAN TAKE PLACE...AND NOT
IDEAL UPPER JET DYNAMICS OVERHEAD.

MOST OF THE REST OF THE WEEK SHOULD BE RATHER QUIET AND SEASONABLE
FOR THE AREA. SOME RESIDUAL CHCS OF PCPN WILL HOLD ON TUE UNTIL THE
SECONDARY SHORT WAVE MOVES THROUGH. AFTER THAT...WE GET INTO A
NEARLY ZONAL FLOW WITH LOWER MICHIGAN JUST DOWNSTREAM OF SOME
RIDGING.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 153 PM EDT FRI AUG 29 2014

WIDELY SCATTERED THUNDERSTORMS CAN NOT BE COMPLETED RULED OUT ANY
TIME OVER THE NEXT 24 HOURS...HOWEVER I ATTEMPTED TO SHOW WHEN
STORMS WOULD BE THE MOST LIKELY WITHIN THE 18Z TAFS.

INSTABILITY WILL BUILD THROUGH THIS AFTERNOON...HOWEVER THERE IS
NOT A FOCUSED TRIGGER TO START ANYTHING SIGNIFICANT...SO LEFT
STORMS OUT OF THE TAFS UNTIL AFTER 01Z...HOWEVER AN ISOLATED
STORM IS POSSIBLE PRIOR TO THAT. THERE IS A LOW LEVEL JET THAT
DEVELOPS THIS EVENING AND MOVES IN TOWARD SOUTHERN LAKE MICHIGAN.
I HAVE STORMS IN THE TAFS AT AZO AND BTL...BUT FURTHER NORTH AND
EAST ANY STORMS SHOULD WEAKEN...SO ONLY HAVE SHOWERS ELSEWHERE.
ANY STORMS SHOULD DIMINISH AFTER MIDNIGHT AS THE INSTABILITY
LESSENS.

ANOTHER ROUND OF STORMS WILL BECOME POSSIBLE AGAIN THROUGH
MID/LATE SATURDAY MORNING AND INTO EARLY AFTERNOON ACROSS THE
ENTIRE AREA AS INSTABILITY SHOULD INCREASE AGAIN ALONG WITH A
MORE FAVORABLE PUSH OF MOISTURE.

VFR WITH PATCHY MVFR IS EXPECTED OVER THE NEXT 24 HOURS OUTSIDE OF
ANY STORMS.

&&

.MARINE...
ISSUED AT 1130 AM EDT FRI AUG 29 2014

KEPT THE HAZARDS GOING. SOUTHEAST WINDS BECOME MORE SOUTHERLY AND
INCREASE. THIS SHOULD RESULT IN WAVES POTENTIALLY CLIMBING ABOVE 4 FT.


&&

.HYDROLOGY...
ISSUED AT 328 PM EDT THU AUG 28 2014

THE HEAVY RAIN THREAT APPEARS TO BE LIMITED TO THE MUSKEGON AND
PERE MARQUETTE BASINS AS AN INCH OF QPF CAN BE EXPECTED THERE BY
SUNDAY MORNING...WHICH WOULD RESULT IN RISES BY EARLY NEXT WEEK.
MUCH LESS RAIN IS EXPECTED IN THE GRAND AND KALAMAZOO RIVER
BASINS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM 8 PM EDT THIS EVENING THROUGH
     SATURDAY EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR LMZ848-849.

     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 11 PM EDT
     SATURDAY FOR LMZ844>847.

&&

$$

UPDATE...MJS
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...JK
HYDROLOGY...OSTUNO
MARINE...MJS








000
FXUS63 KGRR 291533
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1133 AM EDT FRI AUG 29 2014

LATEST UPDATE...
UPDATE/MARINE

.SYNOPSIS...
ISSUED AT 325 AM EDT FRI AUG 29 2014

SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE TODAY AS A WARM FRONT
MOVES THROUGH THE AREA. MORE WIDESPREAD THUNDERSTORM ACTIVITY IS
EXPECTED SATURDAY AHEAD OF THE COLD FRONT...WHICH COMES THROUGH
EARLY SUNDAY MORNING. BEHIND THE COLD FRONT ON SUNDAY EXPECT
PARTIAL CLEARING BY AFTERNOON. THEN A STRONG COLD FRONT WILL BRING
THE RISK OF ADDI TONAL STORMS MONDAY.

&&

.UPDATE...
ISSUED AT 1130 AM EDT FRI AUG 29 2014

LOWERED TEMPERATURES SLIGHTLY AND ADDED A RISK FOR THUNDERSTORMS
THIS AFTERNOON. ELEVATED INSTABILITY MOVES IN FOR THE AFTERNOON.
ALSO RADAR SHOWS CONVECTION CROSSING THE LAKE. CLOUDS WILL LIKELY
LIMIT HIGH TEMPERATURES TODAY. WARMEST READINGS MAY BE LATER IN
THE AFTERNOON WHEN WE WILL POTENTIALLY SEE MORE SUN.


&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 325 AM EDT FRI AUG 29 2014

WE ARE TRACKING SHOWERS AND THUNDERSTORMS TODAY THROUGH SATURDAY
NIGHT. WHILE THERE COULD BE SOME SHOWERS AND ISOLATED THUNDERSTORMS
AROUND TODAY....IT WOULD SEEM OUR BEST POTENTIAL FOR WIDESPREAD
CONVECTION IS SATURDAY AS THE UPPER WAVE MOVES THROUGH.

THE BIG PICTURE FINDS A OPENING UP SOUTHERN STREAM CLOSED UPPER
LOW MOVING EAST AS IT SHEARS OUT AND MOVES OVER MICHIGAN DURING
THE DAY TIME SATURDAY. THE MODELS AS NEARLY ALWAYS WEAK THESE
FEATURE TO FAST SO I WOULD EXPECT STRONG DYNAMICS SATURDAY THEN
ANY OF THE MODELS CURRENTLY WOULD SUGGEST. IN ANY EVENT AS THIS
UPPER WAVE HEADS TOWARD MICHIGAN IT DISPLACES A SHORTWAVE RIDGE
CURRENTLY IN PLACE OVER MICHIGAN. THAT RESULTS IN A SURGE OF MID
LEVEL MOISTURE THAT SHOULD LEAD TO SOME SHOWER AND THUNDERSTORM
ACTIVITY OVER THE WESTERN AND NORTHER SECTIONS OF THE CWA TODAY.
THEN THE PASSAGE OF THE MAIN SYSTEM SATURDAY WILL BRING MORE
WIDESPREAD CONVECTION TO THE AREA.

LOOKING AT THE 1000/850 MOISTURE TRANSPORT VECTORS FROM THE
GFS...NAM AND ECMWF FOR TODAY THE STORY THEY TELL IS SIMILAR TO
WHAT THEY SHOWED YESTERDAY AND THE DAY BEFORE THAT. FOR THE MOST
PART THE BEST MOISTURE TRANSPORT WILL BE NORTH AND WEST OF THE GRR
CWA TODAY. THE LOW LEVEL JET AXIS IS WEST OF MICHIGAN EARLY THIS
MORNING AND IS MOSTLY OVER NORTHERN LOWER AND UPPER MICHIGAN THIS
AFTERNOON INTO TONIGHT. ALSO THE INSTABILITY IS RATHER LIMITED AND
WHAT THERE IS OF IT IS MOSTLY OVER WESTERN SECTIONS OF LOWER
MICHIGAN INTO THIS AFTERNOON. THE SHORTWAVE RIDGE AHEAD OF THE
UPPER WAVE HAS BROUGHT TO WARM OF AIR ABOVE 700 MB SO THAT
VERTICAL TOTALS ARE MARGINAL AT BEST FOR THUNDERSTORMS TODAY. WHAT
BRING THE SHOWERS TO THE AREA TODAY IS A SURGE OF MID LEVEL
MOISTURE AS THE PRECIPITABLE WATER SURGES FROM UNDER A SEVEN TENTS
OF AN INCH EARLY THIS MORNING TO ABOVE ONE AND THREE QUARTER
INCHES OVER MOST OF THE CWA BY NOON. THE FOCUS OF THIS WILL BE ON
THE WARM FRONT NEAR THE AXIS OF THE LOW LEVEL JET. THAT MEANS MOST
OF THE CONVECTION WILL BE NORTH AND WEST OF THE GRR CWA TODAY.

SATURDAY IS WHEN THE MAIN UPPER WAVE MOVES THROUGH THE AREA AND
THERE IS WORKABLE LOW LEVEL JET IN THE AREA AND SOME UPPER LEVEL
JET SUPPORT SO WE SHOULD HAVE WIDESPREAD SHOWERS AND A FEW NON
SEVERE THUNDERSTORMS (CAPE IS LIMITED AND DEEP LAYER SHEAR IS WEAK
TOO).

ALL OF THIS MOVES OUT SATURDAY NIGHT AND SUNDAY FINES US WITH
SHORT WAVER RIDING. SO I EXPECT CLEARING TO OCCUR DURING THE DAY
SUNDAY AS DRY AIR MOVES IN FROM THE NORTHWEST.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 325 AM
EDT FRI AUG 29 2014

THE MAIN WEATHER IN THE LONG TERM WILL BE FOCUSED ON THE CONVECTION
CHCS EARLY ON IN THE PERIOD WITH A SYSTEM THAT WILL BE MOVING
THROUGH THE AREA. THE AREA WILL SEE A BREAK IN THE WEATHER FOR SUN
NIGHT IN THE WAKE OF THE DEPARTING SYSTEM FROM SAT/SAT NIGHT...AND
WELL OUT AHEAD OF THE SYSTEM POISED TO MOVE THROUGH THE AREA ON MON.

THE BREAK WILL BE A SHORT ONE AS THE STORM CHCS WILL BE INCREASING
ON MON MORNING AND LASTING INTO MON EVENING. SHORT WAVE ENERGY
EXPECTED TO COME ONSHORE ACROSS OREGON ON SAT WILL TRAVERSE THE
COUNTRY OVER THE HOLIDAY WEEKEND AND WILL BE LIFTING INTO ONTARIO BY
MON AFTERNOON. THE SHORT WAVE REMAINS MAINLY NORTH OF THE AREA.
HOWEVER THE ASSOCIATED LLJ AND STRONG MOISTURE TRANSPORT DOES MOVE
RIGHT INTO THE AREA MON. WE ENVISION A RESIDUAL LINE OF SHOWERS/
STORMS COMING INTO THE AREA FROM THE WEST ON MON...AND STRENGTHENING
AS IT ENCOUNTERS AN INCREASINGLY UNSTABLE AIR MASS WITH DIURNAL
HEATING THAT TAKES PLACE.

WE CAN NOT RULE SOME OF THE STORMS BECOMING SEVERE MON. DEEP LAYER
SHEAR WILL BE ON THE INCREASE WITH THE UPPER JET NEARBY. LI/S ARE
EXPECTED TO DROP DOWN AROUND -6C WITH CAPES APPROACHING OVER 1500
J/KG. THE LLJ OVERHEAD WILL INCREASE THE 0-3 KM SHEAR WHICH WILL
HELP THE CAUSE. THE LIMITATIONS OF POSSIBLE SEVERE WEATHER WOULD BE
LIMITED INSTABILITY IF NOT MUCH HEATING CAN TAKE PLACE...AND NOT
IDEAL UPPER JET DYNAMICS OVERHEAD.

MOST OF THE REST OF THE WEEK SHOULD BE RATHER QUIET AND SEASONABLE
FOR THE AREA. SOME RESIDUAL CHCS OF PCPN WILL HOLD ON TUE UNTIL THE
SECONDARY SHORT WAVE MOVES THROUGH. AFTER THAT...WE GET INTO A
NEARLY ZONAL FLOW WITH LOWER MICHIGAN JUST DOWNSTREAM OF SOME
RIDGING.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 740 AM EDT FRI AUG 29 2014

ALL OF THE HIGH RESOLUTION MODELS (HRRR 09Z AND RAP 10Z) SHOW THE
AREA OF SCATTERED SHOWERS OVER LAKE MICHIGAN BECOMING A SOLID AREA
OF SHOWERS WITH EMBEDDED HEAVER RAIN SHOWERS (INSTABILITY QUESTIONABLE
FOR THUNDERSTORMS). THE AREA OF SHOWERS WILL IMPACT THE TAF SITES
FROM AROUND 15Z TILL AROUND 21Z BEFORE DISSIPATING.

I ALSO ADDED MVFR CIGS AFTER 07Z IN THE WESTERN TAF SITES TO
REFLECT INCREASED LOW LEVEL MOISTURE ADVECTION AS THE UPPER
SHORTWAVE GETS CLOSER TO LOWER MICHIGAN. SO EXPECT MVFR VSBY/CIGS
IN SHOWERS AT MOST OF THE TAR SITES FROM 15Z TILL 19Z....THEN
BECOMING VFR.


&&

.MARINE...
ISSUED AT 1130 AM EDT FRI AUG 29 2014

KEPT THE HAZARDS GOING. SOUTHEAST WINDS BECOME MORE SOUTHERLY AND
INCREASE. THIS SHOULD RESULT IN WAVES POTENTIALLY CLIMBING ABOVE 4 FT.

&&

.HYDROLOGY...
ISSUED AT 328 PM EDT THU AUG 28 2014

THE HEAVY RAIN THREAT APPEARS TO BE LIMITED TO THE MUSKEGON AND
PERE MARQUETTE BASINS AS AN INCH OF QPF CAN BE EXPECTED THERE BY
SUNDAY MORNING...WHICH WOULD RESULT IN RISES BY EARLY NEXT WEEK.
MUCH LESS RAIN IS EXPECTED IN THE GRAND AND KALAMAZOO RIVER
BASINS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM 8 PM EDT THIS EVENING THROUGH
     SATURDAY EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR LMZ848-849.

     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 11 PM EDT
     SATURDAY FOR LMZ844>847.

&&

$$

UPDATE...MJS
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...OSTUNO
MARINE...MJS







000
FXUS63 KGRR 291533
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1133 AM EDT FRI AUG 29 2014

LATEST UPDATE...
UPDATE/MARINE

.SYNOPSIS...
ISSUED AT 325 AM EDT FRI AUG 29 2014

SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE TODAY AS A WARM FRONT
MOVES THROUGH THE AREA. MORE WIDESPREAD THUNDERSTORM ACTIVITY IS
EXPECTED SATURDAY AHEAD OF THE COLD FRONT...WHICH COMES THROUGH
EARLY SUNDAY MORNING. BEHIND THE COLD FRONT ON SUNDAY EXPECT
PARTIAL CLEARING BY AFTERNOON. THEN A STRONG COLD FRONT WILL BRING
THE RISK OF ADDI TONAL STORMS MONDAY.

&&

.UPDATE...
ISSUED AT 1130 AM EDT FRI AUG 29 2014

LOWERED TEMPERATURES SLIGHTLY AND ADDED A RISK FOR THUNDERSTORMS
THIS AFTERNOON. ELEVATED INSTABILITY MOVES IN FOR THE AFTERNOON.
ALSO RADAR SHOWS CONVECTION CROSSING THE LAKE. CLOUDS WILL LIKELY
LIMIT HIGH TEMPERATURES TODAY. WARMEST READINGS MAY BE LATER IN
THE AFTERNOON WHEN WE WILL POTENTIALLY SEE MORE SUN.


&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 325 AM EDT FRI AUG 29 2014

WE ARE TRACKING SHOWERS AND THUNDERSTORMS TODAY THROUGH SATURDAY
NIGHT. WHILE THERE COULD BE SOME SHOWERS AND ISOLATED THUNDERSTORMS
AROUND TODAY....IT WOULD SEEM OUR BEST POTENTIAL FOR WIDESPREAD
CONVECTION IS SATURDAY AS THE UPPER WAVE MOVES THROUGH.

THE BIG PICTURE FINDS A OPENING UP SOUTHERN STREAM CLOSED UPPER
LOW MOVING EAST AS IT SHEARS OUT AND MOVES OVER MICHIGAN DURING
THE DAY TIME SATURDAY. THE MODELS AS NEARLY ALWAYS WEAK THESE
FEATURE TO FAST SO I WOULD EXPECT STRONG DYNAMICS SATURDAY THEN
ANY OF THE MODELS CURRENTLY WOULD SUGGEST. IN ANY EVENT AS THIS
UPPER WAVE HEADS TOWARD MICHIGAN IT DISPLACES A SHORTWAVE RIDGE
CURRENTLY IN PLACE OVER MICHIGAN. THAT RESULTS IN A SURGE OF MID
LEVEL MOISTURE THAT SHOULD LEAD TO SOME SHOWER AND THUNDERSTORM
ACTIVITY OVER THE WESTERN AND NORTHER SECTIONS OF THE CWA TODAY.
THEN THE PASSAGE OF THE MAIN SYSTEM SATURDAY WILL BRING MORE
WIDESPREAD CONVECTION TO THE AREA.

LOOKING AT THE 1000/850 MOISTURE TRANSPORT VECTORS FROM THE
GFS...NAM AND ECMWF FOR TODAY THE STORY THEY TELL IS SIMILAR TO
WHAT THEY SHOWED YESTERDAY AND THE DAY BEFORE THAT. FOR THE MOST
PART THE BEST MOISTURE TRANSPORT WILL BE NORTH AND WEST OF THE GRR
CWA TODAY. THE LOW LEVEL JET AXIS IS WEST OF MICHIGAN EARLY THIS
MORNING AND IS MOSTLY OVER NORTHERN LOWER AND UPPER MICHIGAN THIS
AFTERNOON INTO TONIGHT. ALSO THE INSTABILITY IS RATHER LIMITED AND
WHAT THERE IS OF IT IS MOSTLY OVER WESTERN SECTIONS OF LOWER
MICHIGAN INTO THIS AFTERNOON. THE SHORTWAVE RIDGE AHEAD OF THE
UPPER WAVE HAS BROUGHT TO WARM OF AIR ABOVE 700 MB SO THAT
VERTICAL TOTALS ARE MARGINAL AT BEST FOR THUNDERSTORMS TODAY. WHAT
BRING THE SHOWERS TO THE AREA TODAY IS A SURGE OF MID LEVEL
MOISTURE AS THE PRECIPITABLE WATER SURGES FROM UNDER A SEVEN TENTS
OF AN INCH EARLY THIS MORNING TO ABOVE ONE AND THREE QUARTER
INCHES OVER MOST OF THE CWA BY NOON. THE FOCUS OF THIS WILL BE ON
THE WARM FRONT NEAR THE AXIS OF THE LOW LEVEL JET. THAT MEANS MOST
OF THE CONVECTION WILL BE NORTH AND WEST OF THE GRR CWA TODAY.

SATURDAY IS WHEN THE MAIN UPPER WAVE MOVES THROUGH THE AREA AND
THERE IS WORKABLE LOW LEVEL JET IN THE AREA AND SOME UPPER LEVEL
JET SUPPORT SO WE SHOULD HAVE WIDESPREAD SHOWERS AND A FEW NON
SEVERE THUNDERSTORMS (CAPE IS LIMITED AND DEEP LAYER SHEAR IS WEAK
TOO).

ALL OF THIS MOVES OUT SATURDAY NIGHT AND SUNDAY FINES US WITH
SHORT WAVER RIDING. SO I EXPECT CLEARING TO OCCUR DURING THE DAY
SUNDAY AS DRY AIR MOVES IN FROM THE NORTHWEST.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 325 AM
EDT FRI AUG 29 2014

THE MAIN WEATHER IN THE LONG TERM WILL BE FOCUSED ON THE CONVECTION
CHCS EARLY ON IN THE PERIOD WITH A SYSTEM THAT WILL BE MOVING
THROUGH THE AREA. THE AREA WILL SEE A BREAK IN THE WEATHER FOR SUN
NIGHT IN THE WAKE OF THE DEPARTING SYSTEM FROM SAT/SAT NIGHT...AND
WELL OUT AHEAD OF THE SYSTEM POISED TO MOVE THROUGH THE AREA ON MON.

THE BREAK WILL BE A SHORT ONE AS THE STORM CHCS WILL BE INCREASING
ON MON MORNING AND LASTING INTO MON EVENING. SHORT WAVE ENERGY
EXPECTED TO COME ONSHORE ACROSS OREGON ON SAT WILL TRAVERSE THE
COUNTRY OVER THE HOLIDAY WEEKEND AND WILL BE LIFTING INTO ONTARIO BY
MON AFTERNOON. THE SHORT WAVE REMAINS MAINLY NORTH OF THE AREA.
HOWEVER THE ASSOCIATED LLJ AND STRONG MOISTURE TRANSPORT DOES MOVE
RIGHT INTO THE AREA MON. WE ENVISION A RESIDUAL LINE OF SHOWERS/
STORMS COMING INTO THE AREA FROM THE WEST ON MON...AND STRENGTHENING
AS IT ENCOUNTERS AN INCREASINGLY UNSTABLE AIR MASS WITH DIURNAL
HEATING THAT TAKES PLACE.

WE CAN NOT RULE SOME OF THE STORMS BECOMING SEVERE MON. DEEP LAYER
SHEAR WILL BE ON THE INCREASE WITH THE UPPER JET NEARBY. LI/S ARE
EXPECTED TO DROP DOWN AROUND -6C WITH CAPES APPROACHING OVER 1500
J/KG. THE LLJ OVERHEAD WILL INCREASE THE 0-3 KM SHEAR WHICH WILL
HELP THE CAUSE. THE LIMITATIONS OF POSSIBLE SEVERE WEATHER WOULD BE
LIMITED INSTABILITY IF NOT MUCH HEATING CAN TAKE PLACE...AND NOT
IDEAL UPPER JET DYNAMICS OVERHEAD.

MOST OF THE REST OF THE WEEK SHOULD BE RATHER QUIET AND SEASONABLE
FOR THE AREA. SOME RESIDUAL CHCS OF PCPN WILL HOLD ON TUE UNTIL THE
SECONDARY SHORT WAVE MOVES THROUGH. AFTER THAT...WE GET INTO A
NEARLY ZONAL FLOW WITH LOWER MICHIGAN JUST DOWNSTREAM OF SOME
RIDGING.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 740 AM EDT FRI AUG 29 2014

ALL OF THE HIGH RESOLUTION MODELS (HRRR 09Z AND RAP 10Z) SHOW THE
AREA OF SCATTERED SHOWERS OVER LAKE MICHIGAN BECOMING A SOLID AREA
OF SHOWERS WITH EMBEDDED HEAVER RAIN SHOWERS (INSTABILITY QUESTIONABLE
FOR THUNDERSTORMS). THE AREA OF SHOWERS WILL IMPACT THE TAF SITES
FROM AROUND 15Z TILL AROUND 21Z BEFORE DISSIPATING.

I ALSO ADDED MVFR CIGS AFTER 07Z IN THE WESTERN TAF SITES TO
REFLECT INCREASED LOW LEVEL MOISTURE ADVECTION AS THE UPPER
SHORTWAVE GETS CLOSER TO LOWER MICHIGAN. SO EXPECT MVFR VSBY/CIGS
IN SHOWERS AT MOST OF THE TAR SITES FROM 15Z TILL 19Z....THEN
BECOMING VFR.


&&

.MARINE...
ISSUED AT 1130 AM EDT FRI AUG 29 2014

KEPT THE HAZARDS GOING. SOUTHEAST WINDS BECOME MORE SOUTHERLY AND
INCREASE. THIS SHOULD RESULT IN WAVES POTENTIALLY CLIMBING ABOVE 4 FT.

&&

.HYDROLOGY...
ISSUED AT 328 PM EDT THU AUG 28 2014

THE HEAVY RAIN THREAT APPEARS TO BE LIMITED TO THE MUSKEGON AND
PERE MARQUETTE BASINS AS AN INCH OF QPF CAN BE EXPECTED THERE BY
SUNDAY MORNING...WHICH WOULD RESULT IN RISES BY EARLY NEXT WEEK.
MUCH LESS RAIN IS EXPECTED IN THE GRAND AND KALAMAZOO RIVER
BASINS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM 8 PM EDT THIS EVENING THROUGH
     SATURDAY EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR LMZ848-849.

     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 11 PM EDT
     SATURDAY FOR LMZ844>847.

&&

$$

UPDATE...MJS
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...OSTUNO
MARINE...MJS








000
FXUS63 KGRR 291142
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
742 AM EDT FRI AUG 29 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 325 AM EDT FRI AUG 29 2014

SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE TODAY AS A WARM FRONT
MOVES THROUGH THE AREA. MORE WIDESPREAD THUNDERSTORM ACTIVITY IS
EXPECTED SATURDAY AHEAD OF THE COLD FRONT...WHICH COMES THROUGH
EARLY SUNDAY MORNING. BEHIND THE COLD FRONT ON SUNDAY EXPECT
PARTIAL CLEARING BY AFTERNOON. THEN A STRONG COLD FRONT WILL BRING
THE RISK OF ADDI TONAL STORMS MONDAY.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 325 AM EDT FRI AUG 29 2014

WE ARE TRACKING SHOWERS AND THUNDERSTORMS TODAY THROUGH SATURDAY
NIGHT. WHILE THERE COULD BE SOME SHOWERS AND ISOLATED THUNDERSTORMS
AROUND TODAY....IT WOULD SEEM OUR BEST POTENTIAL FOR WIDESPREAD
CONVECTION IS SATURDAY AS THE UPPER WAVE MOVES THROUGH.

THE BIG PICTURE FINDS A OPENING UP SOUTHERN STREAM CLOSED UPPER
LOW MOVING EAST AS IT SHEARS OUT AND MOVES OVER MICHIGAN DURING
THE DAY TIME SATURDAY. THE MODELS AS NEARLY ALWAYS WEAK THESE
FEATURE TO FAST SO I WOULD EXPECT STRONG DYNAMICS SATURDAY THEN
ANY OF THE MODELS CURRENTLY WOULD SUGGEST. IN ANY EVENT AS THIS
UPPER WAVE HEADS TOWARD MICHIGAN IT DISPLACES A SHORTWAVE RIDGE
CURRENTLY IN PLACE OVER MICHIGAN. THAT RESULTS IN A SURGE OF MID
LEVEL MOISTURE THAT SHOULD LEAD TO SOME SHOWER AND THUNDERSTORM
ACTIVITY OVER THE WESTERN AND NORTHER SECTIONS OF THE CWA TODAY.
THEN THE PASSAGE OF THE MAIN SYSTEM SATURDAY WILL BRING MORE
WIDESPREAD CONVECTION TO THE AREA.

LOOKING AT THE 1000/850 MOISTURE TRANSPORT VECTORS FROM THE
GFS...NAM AND ECMWF FOR TODAY THE STORY THEY TELL IS SIMILAR TO
WHAT THEY SHOWED YESTERDAY AND THE DAY BEFORE THAT. FOR THE MOST
PART THE BEST MOISTURE TRANSPORT WILL BE NORTH AND WEST OF THE GRR
CWA TODAY. THE LOW LEVEL JET AXIS IS WEST OF MICHIGAN EARLY THIS
MORNING AND IS MOSTLY OVER NORTHERN LOWER AND UPPER MICHIGAN THIS
AFTERNOON INTO TONIGHT. ALSO THE INSTABILITY IS RATHER LIMITED AND
WHAT THERE IS OF IT IS MOSTLY OVER WESTERN SECTIONS OF LOWER
MICHIGAN INTO THIS AFTERNOON. THE SHORTWAVE RIDGE AHEAD OF THE
UPPER WAVE HAS BROUGHT TO WARM OF AIR ABOVE 700 MB SO THAT
VERTICAL TOTALS ARE MARGINAL AT BEST FOR THUNDERSTORMS TODAY. WHAT
BRING THE SHOWERS TO THE AREA TODAY IS A SURGE OF MID LEVEL
MOISTURE AS THE PRECIPITABLE WATER SURGES FROM UNDER A SEVEN TENTS
OF AN INCH EARLY THIS MORNING TO ABOVE ONE AND THREE QUARTER
INCHES OVER MOST OF THE CWA BY NOON. THE FOCUS OF THIS WILL BE ON
THE WARM FRONT NEAR THE AXIS OF THE LOW LEVEL JET. THAT MEANS MOST
OF THE CONVECTION WILL BE NORTH AND WEST OF THE GRR CWA TODAY.

SATURDAY IS WHEN THE MAIN UPPER WAVE MOVES THROUGH THE AREA AND
THERE IS WORKABLE LOW LEVEL JET IN THE AREA AND SOME UPPER LEVEL
JET SUPPORT SO WE SHOULD HAVE WIDESPREAD SHOWERS AND A FEW NON
SEVERE THUNDERSTORMS (CAPE IS LIMITED AND DEEP LAYER SHEAR IS WEAK
TOO).

ALL OF THIS MOVES OUT SATURDAY NIGHT AND SUNDAY FINES US WITH
SHORT WAVER RIDING. SO I EXPECT CLEARING TO OCCUR DURING THE DAY
SUNDAY AS DRY AIR MOVES IN FROM THE NORTHWEST.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 325 AM
EDT FRI AUG 29 2014

THE MAIN WEATHER IN THE LONG TERM WILL BE FOCUSED ON THE CONVECTION
CHCS EARLY ON IN THE PERIOD WITH A SYSTEM THAT WILL BE MOVING
THROUGH THE AREA. THE AREA WILL SEE A BREAK IN THE WEATHER FOR SUN
NIGHT IN THE WAKE OF THE DEPARTING SYSTEM FROM SAT/SAT NIGHT...AND
WELL OUT AHEAD OF THE SYSTEM POISED TO MOVE THROUGH THE AREA ON MON.

THE BREAK WILL BE A SHORT ONE AS THE STORM CHCS WILL BE INCREASING
ON MON MORNING AND LASTING INTO MON EVENING. SHORT WAVE ENERGY
EXPECTED TO COME ONSHORE ACROSS OREGON ON SAT WILL TRAVERSE THE
COUNTRY OVER THE HOLIDAY WEEKEND AND WILL BE LIFTING INTO ONTARIO BY
MON AFTERNOON. THE SHORT WAVE REMAINS MAINLY NORTH OF THE AREA.
HOWEVER THE ASSOCIATED LLJ AND STRONG MOISTURE TRANSPORT DOES MOVE
RIGHT INTO THE AREA MON. WE ENVISION A RESIDUAL LINE OF SHOWERS/
STORMS COMING INTO THE AREA FROM THE WEST ON MON...AND STRENGTHENING
AS IT ENCOUNTERS AN INCREASINGLY UNSTABLE AIR MASS WITH DIURNAL
HEATING THAT TAKES PLACE.

WE CAN NOT RULE SOME OF THE STORMS BECOMING SEVERE MON. DEEP LAYER
SHEAR WILL BE ON THE INCREASE WITH THE UPPER JET NEARBY. LI/S ARE
EXPECTED TO DROP DOWN AROUND -6C WITH CAPES APPROACHING OVER 1500
J/KG. THE LLJ OVERHEAD WILL INCREASE THE 0-3 KM SHEAR WHICH WILL
HELP THE CAUSE. THE LIMITATIONS OF POSSIBLE SEVERE WEATHER WOULD BE
LIMITED INSTABILITY IF NOT MUCH HEATING CAN TAKE PLACE...AND NOT
IDEAL UPPER JET DYNAMICS OVERHEAD.

MOST OF THE REST OF THE WEEK SHOULD BE RATHER QUIET AND SEASONABLE
FOR THE AREA. SOME RESIDUAL CHCS OF PCPN WILL HOLD ON TUE UNTIL THE
SECONDARY SHORT WAVE MOVES THROUGH. AFTER THAT...WE GET INTO A
NEARLY ZONAL FLOW WITH LOWER MICHIGAN JUST DOWNSTREAM OF SOME
RIDGING.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 740 AM EDT FRI AUG 29 2014

ALL OF THE HIGH RESOLUTION MODELS (HRRR 09Z AND RAP 10Z) SHOW THE
AREA OF SCATTERED SHOWERS OVER LAKE MICHIGAN BECOMING A SOLID AREA
OF SHOWERS WITH EMBEDDED HEAVER RAIN SHOWERS (INSTABILITY QUESTIONABLE
FOR THUNDERSTORMS). THE AREA OF SHOWERS WILL IMPACT THE TAF SITES
FROM AROUND 15Z TILL AROUND 21Z BEFORE DISSIPATING.

I ALSO ADDED MVFR CIGS AFTER 07Z IN THE WESTERN TAF SITES TO
REFLECT INCREASED LOW LEVEL MOISTURE ADVECTION AS THE UPPER
SHORTWAVE GETS CLOSER TO LOWER MICHIGAN. SO EXPECT MVFR VSBY/CIGS
IN SHOWERS AT MOST OF THE TAR SITES FROM 15Z TILL 19Z....THEN
BECOMING VFR.

&&

.MARINE...
ISSUED AT 325 AM EDT FRI AUG 29 2014

WE WILL BE HOISTING A SMALL CRAFT ADVISORY FOR THE NRN MARINE ZONES
FOR TODAY AND LASTING THROUGH SAT. WE WILL ALSO HOIST A SMALL CRAFT
ADVISORY FOR THE REMAINDER OF THE ZONES FOR TONIGHT AND SAT. THE
GRADIENT WILL BE INCREASING AHEAD OF THE INCOMING SYSTEM OUT OF THE
SOUTH. THIS WILL LAST INTO SAT EVENING BEFORE IT DIMINISHES A BIT.


&&

.HYDROLOGY...
ISSUED AT 328 PM EDT THU AUG 28 2014

THE HEAVY RAIN THREAT APPEARS TO BE LIMITED TO THE MUSKEGON AND
PERE MARQUETTE BASINS AS AN INCH OF QPF CAN BE EXPECTED THERE BY
SUNDAY MORNING...WHICH WOULD RESULT IN RISES BY EARLY NEXT WEEK.
MUCH LESS RAIN IS EXPECTED IN THE GRAND AND KALAMAZOO RIVER
BASINS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM THIS EVENING THROUGH SATURDAY
     EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 11 PM EDT
     SATURDAY FOR LMZ848-849.

     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 11 PM EDT
     SATURDAY FOR LMZ844>847.

&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...OSTUNO
MARINE...NJJ







000
FXUS63 KGRR 291142
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
742 AM EDT FRI AUG 29 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 325 AM EDT FRI AUG 29 2014

SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE TODAY AS A WARM FRONT
MOVES THROUGH THE AREA. MORE WIDESPREAD THUNDERSTORM ACTIVITY IS
EXPECTED SATURDAY AHEAD OF THE COLD FRONT...WHICH COMES THROUGH
EARLY SUNDAY MORNING. BEHIND THE COLD FRONT ON SUNDAY EXPECT
PARTIAL CLEARING BY AFTERNOON. THEN A STRONG COLD FRONT WILL BRING
THE RISK OF ADDI TONAL STORMS MONDAY.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 325 AM EDT FRI AUG 29 2014

WE ARE TRACKING SHOWERS AND THUNDERSTORMS TODAY THROUGH SATURDAY
NIGHT. WHILE THERE COULD BE SOME SHOWERS AND ISOLATED THUNDERSTORMS
AROUND TODAY....IT WOULD SEEM OUR BEST POTENTIAL FOR WIDESPREAD
CONVECTION IS SATURDAY AS THE UPPER WAVE MOVES THROUGH.

THE BIG PICTURE FINDS A OPENING UP SOUTHERN STREAM CLOSED UPPER
LOW MOVING EAST AS IT SHEARS OUT AND MOVES OVER MICHIGAN DURING
THE DAY TIME SATURDAY. THE MODELS AS NEARLY ALWAYS WEAK THESE
FEATURE TO FAST SO I WOULD EXPECT STRONG DYNAMICS SATURDAY THEN
ANY OF THE MODELS CURRENTLY WOULD SUGGEST. IN ANY EVENT AS THIS
UPPER WAVE HEADS TOWARD MICHIGAN IT DISPLACES A SHORTWAVE RIDGE
CURRENTLY IN PLACE OVER MICHIGAN. THAT RESULTS IN A SURGE OF MID
LEVEL MOISTURE THAT SHOULD LEAD TO SOME SHOWER AND THUNDERSTORM
ACTIVITY OVER THE WESTERN AND NORTHER SECTIONS OF THE CWA TODAY.
THEN THE PASSAGE OF THE MAIN SYSTEM SATURDAY WILL BRING MORE
WIDESPREAD CONVECTION TO THE AREA.

LOOKING AT THE 1000/850 MOISTURE TRANSPORT VECTORS FROM THE
GFS...NAM AND ECMWF FOR TODAY THE STORY THEY TELL IS SIMILAR TO
WHAT THEY SHOWED YESTERDAY AND THE DAY BEFORE THAT. FOR THE MOST
PART THE BEST MOISTURE TRANSPORT WILL BE NORTH AND WEST OF THE GRR
CWA TODAY. THE LOW LEVEL JET AXIS IS WEST OF MICHIGAN EARLY THIS
MORNING AND IS MOSTLY OVER NORTHERN LOWER AND UPPER MICHIGAN THIS
AFTERNOON INTO TONIGHT. ALSO THE INSTABILITY IS RATHER LIMITED AND
WHAT THERE IS OF IT IS MOSTLY OVER WESTERN SECTIONS OF LOWER
MICHIGAN INTO THIS AFTERNOON. THE SHORTWAVE RIDGE AHEAD OF THE
UPPER WAVE HAS BROUGHT TO WARM OF AIR ABOVE 700 MB SO THAT
VERTICAL TOTALS ARE MARGINAL AT BEST FOR THUNDERSTORMS TODAY. WHAT
BRING THE SHOWERS TO THE AREA TODAY IS A SURGE OF MID LEVEL
MOISTURE AS THE PRECIPITABLE WATER SURGES FROM UNDER A SEVEN TENTS
OF AN INCH EARLY THIS MORNING TO ABOVE ONE AND THREE QUARTER
INCHES OVER MOST OF THE CWA BY NOON. THE FOCUS OF THIS WILL BE ON
THE WARM FRONT NEAR THE AXIS OF THE LOW LEVEL JET. THAT MEANS MOST
OF THE CONVECTION WILL BE NORTH AND WEST OF THE GRR CWA TODAY.

SATURDAY IS WHEN THE MAIN UPPER WAVE MOVES THROUGH THE AREA AND
THERE IS WORKABLE LOW LEVEL JET IN THE AREA AND SOME UPPER LEVEL
JET SUPPORT SO WE SHOULD HAVE WIDESPREAD SHOWERS AND A FEW NON
SEVERE THUNDERSTORMS (CAPE IS LIMITED AND DEEP LAYER SHEAR IS WEAK
TOO).

ALL OF THIS MOVES OUT SATURDAY NIGHT AND SUNDAY FINES US WITH
SHORT WAVER RIDING. SO I EXPECT CLEARING TO OCCUR DURING THE DAY
SUNDAY AS DRY AIR MOVES IN FROM THE NORTHWEST.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 325 AM
EDT FRI AUG 29 2014

THE MAIN WEATHER IN THE LONG TERM WILL BE FOCUSED ON THE CONVECTION
CHCS EARLY ON IN THE PERIOD WITH A SYSTEM THAT WILL BE MOVING
THROUGH THE AREA. THE AREA WILL SEE A BREAK IN THE WEATHER FOR SUN
NIGHT IN THE WAKE OF THE DEPARTING SYSTEM FROM SAT/SAT NIGHT...AND
WELL OUT AHEAD OF THE SYSTEM POISED TO MOVE THROUGH THE AREA ON MON.

THE BREAK WILL BE A SHORT ONE AS THE STORM CHCS WILL BE INCREASING
ON MON MORNING AND LASTING INTO MON EVENING. SHORT WAVE ENERGY
EXPECTED TO COME ONSHORE ACROSS OREGON ON SAT WILL TRAVERSE THE
COUNTRY OVER THE HOLIDAY WEEKEND AND WILL BE LIFTING INTO ONTARIO BY
MON AFTERNOON. THE SHORT WAVE REMAINS MAINLY NORTH OF THE AREA.
HOWEVER THE ASSOCIATED LLJ AND STRONG MOISTURE TRANSPORT DOES MOVE
RIGHT INTO THE AREA MON. WE ENVISION A RESIDUAL LINE OF SHOWERS/
STORMS COMING INTO THE AREA FROM THE WEST ON MON...AND STRENGTHENING
AS IT ENCOUNTERS AN INCREASINGLY UNSTABLE AIR MASS WITH DIURNAL
HEATING THAT TAKES PLACE.

WE CAN NOT RULE SOME OF THE STORMS BECOMING SEVERE MON. DEEP LAYER
SHEAR WILL BE ON THE INCREASE WITH THE UPPER JET NEARBY. LI/S ARE
EXPECTED TO DROP DOWN AROUND -6C WITH CAPES APPROACHING OVER 1500
J/KG. THE LLJ OVERHEAD WILL INCREASE THE 0-3 KM SHEAR WHICH WILL
HELP THE CAUSE. THE LIMITATIONS OF POSSIBLE SEVERE WEATHER WOULD BE
LIMITED INSTABILITY IF NOT MUCH HEATING CAN TAKE PLACE...AND NOT
IDEAL UPPER JET DYNAMICS OVERHEAD.

MOST OF THE REST OF THE WEEK SHOULD BE RATHER QUIET AND SEASONABLE
FOR THE AREA. SOME RESIDUAL CHCS OF PCPN WILL HOLD ON TUE UNTIL THE
SECONDARY SHORT WAVE MOVES THROUGH. AFTER THAT...WE GET INTO A
NEARLY ZONAL FLOW WITH LOWER MICHIGAN JUST DOWNSTREAM OF SOME
RIDGING.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 740 AM EDT FRI AUG 29 2014

ALL OF THE HIGH RESOLUTION MODELS (HRRR 09Z AND RAP 10Z) SHOW THE
AREA OF SCATTERED SHOWERS OVER LAKE MICHIGAN BECOMING A SOLID AREA
OF SHOWERS WITH EMBEDDED HEAVER RAIN SHOWERS (INSTABILITY QUESTIONABLE
FOR THUNDERSTORMS). THE AREA OF SHOWERS WILL IMPACT THE TAF SITES
FROM AROUND 15Z TILL AROUND 21Z BEFORE DISSIPATING.

I ALSO ADDED MVFR CIGS AFTER 07Z IN THE WESTERN TAF SITES TO
REFLECT INCREASED LOW LEVEL MOISTURE ADVECTION AS THE UPPER
SHORTWAVE GETS CLOSER TO LOWER MICHIGAN. SO EXPECT MVFR VSBY/CIGS
IN SHOWERS AT MOST OF THE TAR SITES FROM 15Z TILL 19Z....THEN
BECOMING VFR.

&&

.MARINE...
ISSUED AT 325 AM EDT FRI AUG 29 2014

WE WILL BE HOISTING A SMALL CRAFT ADVISORY FOR THE NRN MARINE ZONES
FOR TODAY AND LASTING THROUGH SAT. WE WILL ALSO HOIST A SMALL CRAFT
ADVISORY FOR THE REMAINDER OF THE ZONES FOR TONIGHT AND SAT. THE
GRADIENT WILL BE INCREASING AHEAD OF THE INCOMING SYSTEM OUT OF THE
SOUTH. THIS WILL LAST INTO SAT EVENING BEFORE IT DIMINISHES A BIT.


&&

.HYDROLOGY...
ISSUED AT 328 PM EDT THU AUG 28 2014

THE HEAVY RAIN THREAT APPEARS TO BE LIMITED TO THE MUSKEGON AND
PERE MARQUETTE BASINS AS AN INCH OF QPF CAN BE EXPECTED THERE BY
SUNDAY MORNING...WHICH WOULD RESULT IN RISES BY EARLY NEXT WEEK.
MUCH LESS RAIN IS EXPECTED IN THE GRAND AND KALAMAZOO RIVER
BASINS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM THIS EVENING THROUGH SATURDAY
     EVENING FOR MIZ037-043-050-056-064-071.

LM...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 11 PM EDT
     SATURDAY FOR LMZ848-849.

     SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 11 PM EDT
     SATURDAY FOR LMZ844>847.

&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...OSTUNO
MARINE...NJJ








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