Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 052347
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
747 PM EDT SUN JUL 5 2015

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 328 PM EDT SUN JUL 5 2015

THE AREA WILL SEE WARM AND QUIET WEATHER CONTINUE FROM TONIGHT AND
THROUGH THE DAY ON MONDAY. SOME HAZE/SMOKE FROM THE CANADIAN FIRES
AND HIGH CLOUDS WILL AFFECT THE AREA...WITH LITTLE IMPACT.
TEMPERATURES WILL REMAIN WARM TONIGHT...AND WILL WARM WELL INTO THE
80S ON MONDAY.

SHOWERS AND A FEW THUNDERSTORMS WILL MOVE IN FROM THE NORTHWEST
MONDAY NIGHT AND THEN MOVE OUT OF THE AREA ON TUESDAY. AT THIS
TIME...SOME STRONG STORMS WILL BE POSSIBLE BUT SEVERE WEATHER IS NOT
LIKELY.

MUCH COOLER WEATHER WILL MOVE IN LATER ON TUESDAY AND CONTINUE
THROUGH MID WEEK. THERE WILL BE SOME RAIN CHANCES FOR THE END OF THE
WEEK.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 328 PM EDT SUN JUL 5 2015

OUR MAIN ITEMS OF INTEREST IN THE SHORT TERM PORTION OF THE FCST
REMAIN THE HEAT INDICES ON MON...AND PCPN AND SEVERE CHCS WITH THE
FRONT FOR MON NIGHT/TUE.

THE AREA LOOKS TO REMAIN DRY NOW THROUGH THE ENTIRE DAY PERIOD OF
MON. WE WILL BE IN BETWEEN TWO SYSTEMS...ONE TO OUR SE AND
ANOTHER TO OUR WEST THROUGH MON. A SHORT WAVE RIDGE WILL HOLD
ACROSS THE AREA BETWEEN THE TWO AFOREMENTIONED SYSTEMS. THIS WILL
KEEP THE ATMOSPHERE DRY AND CAPPED THROUGH MON.

WE EXPECT MAX TEMPS ON MON TO TOP OUT IN THE UPPER 80S WITH HEAT
INDICES GENERALLY EXPECTED TO REACH THE LOWER 90S. H850 TEMPS OF
AROUND 15C TODAY ARE SUPPORTING UP TO MID 80S...AND H850 TEMPS WILL
INCREASE A LITTLE TO GO ALONG WITH BETTER MIXING ON MON. DEW POINTS
LOOK TO MAX OUT IN THE LOW TO POSSIBLY MID 60S. A SSW WIND AT THE
SFC WILL ALLOW ALMOST ALL LOCATIONS TO GET IN ON THE HEAT...EXCEPT
THE IMMEDIATE COAST.

THE TIMING OF THE SHOWERS AND STORMS WITH THE FRONT REMAINS MOSTLY
UNCHANGED EXCEPT FOR MAYBE A SLIGHT DELAY OF THE FRONT. THE TIMING
OF LATER MON NIGHT INTO TUE REMAINS QUITE UNFAVORABLE FROM A
INSTABILITY STANDPOINT. CAPES ARE ON THE ORDER OF ONLY A FEW HUNDRED
J/KG...ARE ELEVATED IN NATURE...AND ARE FAIRLY THIN ON FCST
SOUNDINGS. GOOD DEEP LAYER SHEAR IS LAGGING BEHIND THE FRONT AND
INSTABILITY. EVEN THE SE PORTION OF THE CWFA DOES NOT LOOK LIKELY TO
EXPERIENCE SEVERE WEATHER WITH THE FRONTAL PASSAGE BY 18Z TUE. A 40
KNOT LLJ DOES SUPPORT DECENT MOISTURE TRANSPORT RESULTING IN A GOOD
CHC THAT MOST LOCATIONS WILL SEE RAIN.

WE SHOULD SEE RAIN CLEAR OUT FROM NW TO SE TUE MORNING INTO EARLY
TUE AFTERNOON. A MUCH COOLER AIR MASS WILL BE USHERED IN ON NW
WINDS. TEMPS WILL BE SO COOL...THAT SOME 40S WILL BE POSSIBLE UP
NORTH TUE NIGHT.

.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 328 PM EDT SUN JUL 5 2015

LONG TERM BEGINS WITH ZONAL FLOW ALOFT...WHICH TRANSITIONS INTO
RIDGING BY THE END OF THE WEEK AND EARLY INTO NEXT WEEKEND. WHAT
THIS MEANS TEMPERATURE WISE IS COOLER THAN NORMAL READINGS TO BEGIN
THE LONG TERM ON WEDNESDAY WITH HIGHS LIKELY REMAINING IN THE 70S.
BY LATE IN THE WEEK...A BERMUDA HIGH ALOFT RETROGRADES EAST OFF THE
ATLANTIC AND INTO THE SOUTHEAST U.S. LOWER MICHIGAN WILL BE ON THE
NORTHERN FRINGES OF THIS HIGH ALOFT...WHICH MEANS BUILDING HEIGHTS
AND WARMER TEMPERATURES. BY LATE IN THE WEEK AND INTO NEXT WEEKEND
WE SHOULD BE INTO THE 80S. AT THIS POINT HAVE LOW TO MID 80S IN THE
FORECAST...BUT COULD SEE THIS BEING BUMPED UP WITH TIME.

THE CHANCE FOR PRECIPITATION PORTION OF THE FORECAST IS NOT STRAIGHT
FORWARD BY ANY MEANS. EVEN WITH THE RIDGING ALOFT LATE IN THE
WEEK...WE ARE STILL ON THE FRINGES OF IT AND THEREFORE REMAIN
SOMEWHAT ZONAL. WHAT THIS MEANS ALMOST THROUGH THE ENTIRE LONG TERM
IS A FRONTAL BOUNDARY WILL BE NEARBY PARALLEL TO THE UPPER FLOW. AS
SHORTWAVES ZIP THROUGH THE FLOW...THE BOUNDARY WILL OSCILLATE
THROUGH THE REGION. HAVE CHANCES (20-40 PCT) FOR SHOWERS AND STORMS
ALMOST EACH PERIOD OF THE EXTENDED...WHICH MATCHES WITH NEIGHBORING
OFFICES. DETAILS ARE QUITE FUZZY GIVEN THE LACK OF CONSISTENCY
BETWEEN THE OPERATIONAL MODELS AND THE DIFFICULTY OF TIMING ROUNDS
OF CONVECTION THROUGH THE FORECAST AREA IN THE DAY 3-7 RANGE.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 747 PM EDT SUN JUL 5 2015

VFR CONDITIONS ARE EXPECTED THIS EVENING...BUT ONCE WINDS GO CALM
OVERNIGHT WE WILL SEE SHALLOW GROUND FOG FORM SIMILAR TO THE PAST
COUPLE NIGHTS. AFTER 06Z...GENERALLY MVFR CONDITIONS IN LIGHT FOG
WILL PREVAIL BUT IFR SHOULD DEVELOP AROUND 08Z TO 10Z WITH SOME
LIFR AT TIMES BEFORE SUNRISE. THE FOG WILL DISSIPATE AFTER 12Z.

WINDS WILL BE LIGHT SOUTHERLY THIS EVENING THEN CALM OVERNIGHT
BEFORE PICKING UP FROM THE SOUTH AND SOUTHWEST ON MONDAY MORNING
WITH SOME GUSTS NEAR 20 KNOTS DURING THE AFTERNOON.

&&

.MARINE...
ISSUED AT 328 PM EDT SUN JUL 5 2015

WE WILL BE ISSUING A SMALL CRAFT ADVISORY FOR THE ENTIRE NEARSHORE
AND A BEACH HAZARDS STATEMENT VALID FROM TOMORROW AFTERNOON THROUGH
MOST OF THE DAY ON TUESDAY.

AS HAS BEEN ADVERTISED...WINDS WILL BE ON THE INCREASE ON MON AS WE
SEE THE NEXT COLD FRONT APPROACH THE AREA LATER. WINDS WILL INCREASE
FIRST ACROSS THE NORTH...AND THEN SPREAD SOUTH INTO MONDAY EVENING.
WINDS WILL HAVE THE POTENTIAL TO BECOME GUSTY AGAIN BEHIND THE FRONT
ON TUE AS WINDS SWITCH TO THE NW.


&&

.HYDROLOGY...
ISSUED AT 1100 AM EDT SUN JUL 5 2015

THERE ARE NO IMMEDIATE HYDRO CONCERNS AT THIS TIME.

PERSISTENT DRY WEATHER HAS ALLOWED RIVERS TO FALL BACK WITHIN
THEIR BANKS OVER THE LAST SEVERAL DAYS. RIVERS EITHER CONTINUE TO
SLOWLY FALL OR HAVE BECOME STABLE. A ROUND OF RAINFALL IS EXPECTED
MONDAY NIGHT WITH QPF AROUND 0.50-0.75 INCHES. THE MORE ACTIVE
STORM TRACK STAYS SOUTH OF THE CWA FOR MOST OF THE WEEK BUT NUDGES
NORTHWARD BY THE END OF THE 7 DAY PERIOD. CONDITIONS MAY BECOME
WET AGAIN TOWARD THE END OF THE WEEK...PENDING THE LOCATION OF THE
BOUNDARY. RAINFALL AMOUNTS THROUGH THE WEEK...AS A WHOLE...ARE
NOT REALLY CONCERNING BUT MORE SO BENEFICIAL WITH THE RECENT DRY
PATTERN.

&&

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

LM...SMALL CRAFT ADVISORY FROM 2 PM MONDAY TO 8 AM EDT TUESDAY FOR
     LMZ844>849.

&&

$$

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


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