000
FXUS63 KAPX 170401
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1201 AM EDT MON JUN 17 2013

.SYNOPSIS...
ISSUED AT 416 PM EDT SUN JUN 16 2013

A WEAK SYSTEM DROPPING INTO THE GREAT LAKES TODAY...WILL SLOWLY EXIT
NORTHEAST INTO QUEBEC MONDAY. THIS PATTERN WILL GENERATE MORE HUMID
CONDITIONS ALONG WITH A FEW THUNDERSTORMS ACROSS NORTHERN MICHIGAN
THROUGH MONDAY. A LARGE AREA OF HIGH PRESSURE WILL MOVE INTO THE
GREAT LAKES AND UPPER MIDWEST MONDAY NIGHT...AND WILL REMAIN NEARLY
STATIONARY OVER THE REGION INTO THURSDAY. THIS PATTERN WILL GENERATE
SOME SUN ALONG WITH NEARLY SEASONAL TEMPERATURES...OVER THE GREAT
LAKES THROUGH MIDWEEK.

&&

.UPDATE...
ISSUED AT 1016 PM EDT SUN JUN 16 2013

COLD FRONT...AIDED BY LAKE SUPERIOR COLD MARINE AIR AND SPOTTY
CONVECTION/ASSOCIATED COLD POOLS...HAS PUSHED JUST SOUTH OF PLN
LATE THIS EVENING. TRAIN OF SHORTWAVES...AND ASSOCIATED POCKETS OF
CONVECTION...CONTINUE HERE AND UPSTREAM AS FAR AS DULUTH MN.
THOUGH SURFACE-BASED INSTABILITY WILL CONTINUE TO DWINDLE...
PERIODIC SHOTS OF DYNAMICS WILL SUPPORT A PRECIP THREAT INTO THE
OVERNIGHT HOURS. THUNDER SHOULD TEND TO DIMINISH TO (AT BEST)
ISOLATED COVERAGE...AND DON/T ANTICIPATE ANY ADDITIONAL THREAT
FOR SEVERE STORMS.

UPDATE ISSUED AT 801 PM EDT SUN JUN 16 2013

A LITTLE BUSIER THAN ANTICIPATED THIS EVENING. HAVE EXPANDED
EVENING POPS A LITTLE BIT SOUTHWARD IN NORTHERN LOWER...AND
NORTHWARD INTO MACKINAC/SE CHIP THIS EVENING. DRIER LOW/MID LEVEL
AIR FLOODING IN HAS ALLOWED SOME CELLS TO BECOME GUSTY WIND
PRODUCERS...THOUGH THIS MAY PLAY ITSELF OUT IN THE NEXT HOUR AS
THE STRONGEST CELL REACHES LAKE HURON AND INSTABILITY WANES.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 416 PM EDT SUN JUN 16 2013

AFTERNOON SURFACE ANALYSIS SHOWS A WAVY FRONTAL BOUNDARY EXTENDING
FROM A LOW OVER NORTHEAST ONTARIO...ARCING SOUTH/SOUTHWEST BACK INTO
SOUTHERN LOWER MICHIGAN THEN STRETCHING WEST ACROSS IOWA/NORTHWEST
MISSOURI AND ACROSS KANSAS.  SECOND AREA OF LOW PRESSURE WAS
SPINNING OVER LAKE WINNIPEG...ASSOCIATED WITH A WEAKENING UPPER
LEVEL DISTURBANCE WHICH IS SPINNING A TRAIN OF SMALL SHORT WAVES
EASTWARD...ONE EVIDENT OVER EASTERN NORTH DAKOTA...A SECOND ALONG
THE MINNESOTA/WISCONSIN BORDER AND A THIRD MOVING EAST ALONG THE
MICHIGAN/WISCONSIN BORDER.

MAIN SHORT WAVE TROUGH OVER MANITOBA WILL DROP SOUTHEAST INTO THE
UPPER MIDWEST BY MONDAY AFTERNOON...WHICH IN TURN WILL ALLOW THE
FRONT OVER NORTHWEST ONTARIO TO SINK INTO LOWER MICHIGAN LATER
TODAY/MONDAY.  BETTER MOISTURE/CLOUD COVER IS LOCATED BEHIND THE
BOUNDARY...WHILE PRECIPITATION AHEAD OF IT DIURNALLY DRIVEN SO SOME
OF THIS WILL FALL APART WITH LOSS OF HEATING.  BUT AM CURIOUS ABOUT
CONVECTION AHEAD OF NORTHWEST MINNESOTA VORTICITY CENTER WHICH IS A
PRETTY HEALTHY LOOKING WAVE.  THIS FEATURE WILL PROBABLY REACH
NORTHWEST LOWER TOWARD MIDNIGHT...AND THINK THAT ASSOCIATED
CONVECTION MAY HAVE ENOUGH INERTIA TO PUSH INTO THE AREA LATER THIS
EVENING.  OVERNIGHT...AS COLD FRONT DROPS IN WILL SEE ANOTHER ROUND
OF PRECIPITATION CHANCES SPREAD IN FROM THE NORTH ALONG AXIS OF
BETTER MOISTURE AND SOME FRONTOGENETIC SUPPORT.

MONDAY SHAPING UP TO BE A CLOUDIER DAY AS FRONT CONTINUES ITS PUSH
SOUTH INTO CENTRAL LOWER MICHIGAN.  RAIN SHOWERS/EMBEDDED
THUNDERSTORMS SHOULD BE ONGOING MONDAY MORNING...BY AFTERNOON THE
TREND SHOULD BE DRIER ACROSS EASTERN UPPER...BUT SOME HEATING
ALONG/AHEAD OF THE BOUNDARY SOUTH OF THE M-72 CORRIDOR MAY ALLOW FOR
ADDITIONAL THUNDERSTORM DEVELOPMENT SIMILAR TO WHAT IS OCCURRING
TODAY ACROSS NORTHERN ONTARIO.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 416 PM EDT SUN JUN 16 2013

MONDAY NIGHT...WITH THE 500 MB TROUGH AXIS EAST OF THE FORECAST
AREA, AND THE FRONT SOUTH OF THE FORECAST AREA, THE REGION DRIES OUT
RAPIDLY. HIGH PRESSURE WILL BUILD INTO THE REGION BY 06Z AND QUICKLY
OVERSPREAD THE REGION OVERNIGHT. THE MOISTURE IN THE 700-500 MB
LAYER DRIES OUT PRETTY QUICK SO THAT BY 09Z THE RH IS DOWN BELOW 10%
ON THE NAM (GFS AND ECMWF IS ABOUT THE SAME). THE 850 MB MOISTURE
TAKES A LITTLE LONGER TIME FOR THE CLEARING, BUT THAT TOO GETS TO
M-55. THE ECMWF IS A LITTLE SLOWER AT CLEARING OUT THE LOWER CLOUDS.
WITH THE NAM AND GFS ON PAR WITH THE FORECAST.

TUESDAY...LOOKED AT THE 850 MB MOISTURE AND THINK THAT THE 50% OR SO
WILL ALLOW THE SKY TO TURN OUT MOSTLY SUNNY, ALTHOUGH IF THE NAM IS
RIGHT PART OF NC LOWER AND E UPPER WILL BE PARTLY SUNNY. WITH THE
SFC HIGH AND THE 500 MB VORT MAX TRAVELING SOUTH OF THE AREA, WILL
EXPECT THAT THE SUBSIDENCE WILL CLEAR OUT THE SKY.

TUESDAY NIGHT...THE CORE OF THE HIGH DROPS SE ACROSS THE STATE.
MOISTURE DRIES A BIT A 850 MB AND WITH THE DRY UPPER LEVELS, WILL GO
MOSTLY CLEAR WITH THE TEMPERATURES DROPPING TO THE MID 40S.

WEDNESDAY...THE HIGH CONTINUES TO MOVE OFF TO THE SOUTHEAST, AND THE
RETURN FLOW BEGINS. WILL GO TOWARD THE GFS MORE OPTIMISTIC FORECAST
WITH THE MOSTLY SUNNY DAY, ALTHOUGH PORTIONS OF THE FORECAST AREA,
LIKE NC LOWER MAY CU UP A BIT FOR A PARTLY SUNNY SKY. OVERNIGHT, A
500 MB SHORTWAVE TROUGH DROPS INTO THE NORTHWEST FLOW AND WITH A
LITTLE MOISTURE WILL ALLOW FOR THE CHANCE OF SHOWERS. THE MODELS ARE
THINNING OUT THE MOISTURE THROUGH THE OVERNIGHT PERIOD, HOWEVER, SO
WILL KEEP THE POPS LOW AT THIS POINT. WITH THE ECMWF, THERE IS ONLY
A GLANCING BLOW TO E UPPER, WHILE THE GFS HAS A SMALL AREA THE GETS
GOING OVER C AND E UPPER. WOULDN`T BE SURPRISED IF NOTHING HAPPENS.

EXTENDED (THURSDAY THROUGH SUNDAY)...THURSDAY, IT LOOKS LIKE WE GET
INTO A NW FLOW PATTERN THAT COULD BRING SCATTERED SHOWERS AND
THUNDERSTORM. HOWEVER, THE MODELS ARE BEGINNING TO BACK OFF OF THAT
IDEA, WITH A FAIR AMOUNT OF DRY AIR IN THE 700-500 MB LAYER AND THE
HUDSON BAY HIGH THAT IS DRIFTING SE OVERNIGHT. FRIDAY, THE MODELS
HAVE BOTH BACKED OFF OF BRINGING ANYTHING THROUGH SO HAVE LOWERED
THE POPS TO SLIGHT CHANCE. FRIDAY NIGHT, LOOKS LIKE THERE COULD BE A
DIRTY RIDGE BRINGING NOCTURNAL THUNDERSTORMS...MAINLY OVERNIGHT. IF
THE MODELS HAVE IT RIGHT, WE COULD MISS OUT OF THIS WITH THE MAIN
ACTION FIRING UP TO THE WEST AND DROPPING SOUTHEAST. SATURDAY,
MODELS HAVE SOME SORT OF CONVECTIVELY FORCED VORT MAX AT 500 MB THAT
IS KICKING OFF MORE SHOWERS AND THUNDERSTORMS. VORT IS SO FORCED ON
THE ECMWF THAT IT KICKS A SFC LOW OUT FROM THAT SFC LOW IN THE
PLAINS. NOT SURE I BELIEVE THAT. WILL KEEP THE CHANCE POPS. SUNDAY,
LOOKS LIKE WE ARE CAUGHT BETWEEN SYSTEMS. THE ECMWF IS DRY AND THE
GFS HAS A LOT OF CONVECTIVELY DRIVEN BULL`S EYES TO THE SOUTH OF US,
THIS DOESN`T INSPIRE A LOT OF CONFIDENCE IN THE FORECAST. SO WILL
KEEP THE CHANCE POPS LOW.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1159 PM EDT SUN JUN 16 2013

MAINLY VFR...THOUGH SOME RISK FOR MVFR CONDITIONS MONDAY MORNING
APN/PLN.

A COLD FRONT WAS SLOWLY MOVING SOUTH ACROSS NORTHERN LOWER MI.
UPPER LEVEL DISTURBANCES WERE INTERACTING WITH THAT FRONT TO
PRODUCE SOME SHRA AND A STRAY TSRA OR TWO. THESE WILL DWINDLE
OVERNIGHT. SOME DEVELOPMENT POSSIBLE MONDAY...ESPECIALLY IN THE
AFTERNOON...BUT THE BEST CHANCE WILL BE SOUTH OF APN AND EAST OF
TVC/MBL. NE WINDS JUST BEHIND THE FRONT WILL TRY TO BRING
COOL/MOIST LOW LEVEL AIR INTO APN/PLN TOWARD DAYBREAK. THIS LOOKS
A LITTLE OVERDONE...AND HAVE OPTED JUST FOR A SCT015 LAYER AND NO
CIG RESTRICTIONS FOR NOW.

LIGHT WINDS OVERNIGHT...N TO NE WINDS (LIGHT) ON MONDAY.

&&

.MARINE...
ISSUED AT 416 PM EDT SUN JUN 16 2013

PRESSURE GRADIENT REMAINS WEAK AS COLD FRONT TO THE NORTH DROPS INTO
THE UPPER LAKES TONIGHT/EARLY MONDAY.  WINDS WILL SHIFT TO A MORE
NORTHEASTERLY DIRECTION OVERNIGHT AS THE BOUNDARY PASSES THE
NEARSHORE ZONES SURROUNDING EASTERN UPPER...WITH A BIT OF AN
EASTERLY SYNOPTIC COMPONENT ALL AREAS MONDAY THROUGH LAND/LAKE
DIFFERENTIAL HEATING WILL RESULT IN LOCAL CHANGES IN WIND
DIRECTION.  HEADLINE CRITERIA CONDITIONS NOT EXPECTED THROUGH MONDAY.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.

&&

$$

UPDATE...JZ
SYNOPSIS...KAB
SHORT TERM...JPB
LONG TERM...JSL
AVIATION...JZ
MARINE...JPB