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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1200 AM EDT SAT OCT 25 2014

.SYNOPSIS...
ISSUED AT 351 PM EDT FRI OCT 24 2014

CLOUDS WILL BRIEFLY DEPART TONIGHT...ONLY TO RETURN LATE AND INTO 
SATURDAY AS A COLD FRONT WORKS THROUGH THE REGION. NO RAIN IS 
EXPECTED WITH THIS FEATURE...BUT WINDY CONDITIONS ARE LIKELY INTO 
SATURDAY NIGHT. SUNDAY LOOKS SEASONABLY COOL BUT NICE WITH HIGH 
PRESSURE IN CONTROL...BEFORE STRENGTHENING LOW PRESSURE OVER THE 
REGION PROVIDES SEVERAL CHANCES FOR RAIN SUNDAY NIGHT THROUGH 
MIDWEEK.

&&

.UPDATE...
ISSUED AT 915 PM EDT FRI OCT 24 2014

HAVE BEEN FIDDLING WITH SKY COVER GRIDS THRU THE EVENING.
DOWNSTATE CLEARING IS TRYING TO EDGE UP INTO THE GLADWIN/
STANDISH/TAWAS AREAS...BUT OTHERWISE LOW CLOUD DECK IS HOLDING
TOUGH ACROSS NORTHERN MI. SOME POSSIBILITY FOR THIS TO WORK UP
INTO OTHER PARTS OF NE LOWER. MEANWHILE...STRATUS AHEAD OF THE
COLD FRONT TO THE WEST IS EXPANDING QUICKLY EAST...AND FILLING IN
ACROSS LAKE MI. SO ELSEWHERE...WE WILL HAVE TO WAIT TIL WE GET
BEHIND THE FRONT SATURDAY FOR ANY SUBSTANTIAL CLEARING. WILL
SUBSEQUENTLY BUMP UP MIN TEMPS IN NORTHERN LOWER MI A HAIR.

VERY BRIEF PRE-FRONTAL PERIOD WHERE MOISTURE DEEPENS UP A SMIDGE.
SUSPECT DRIZZLE WILL LARGELY BE CONFINED TO UPSLOPE LOCALES...AND
WILL DIMINISH MENTION OF SUCH LATE TONIGHT.

&&

.SHORT TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 351 PM EDT FRI OCT 24 2014

HIGH IMPACT WEATHER POTENTIAL: NONE.

PRIMARY FORECAST CHALLENGES: WHETHER THERE WILL BE ENOUGH BREAK IN 
THE CLOUDS OVERNIGHT TO DROP TEMPERATURES LOWER TONIGHT. 

CURRENTLY, WEAK RETURN FLOW OVER THE FORECAST IS HELPING TO KEEP THE 
LOW LEVEL MOISTURE IN NORTHERN MICHIGAN THROUGH THE DAY. THE 
MOISTURE EXTENDS TO THE WEST OVER LAKE MICHIGAN AND INTO EASTERN 
WISCONSIN. TO THE WEST IS THE SFC LOW JUST NORTH OF LAKE WINNIPEG 
AND THE 500 MB SHORTWAVE TROUGH IN THE CANADIAN PRAIRIES.

TONIGHT...WHILE THE CLEARING LINE IN WISCONSIN IS BEGINNING TO HEAD 
OUT OVER LAKE MICHIGAN, MORE MOISTURE IS POOLING IN THE UPPER 
MISSISSIPPI VALLEY AND IS EXPECTED TO MOVE INTO NORTHERN LOWER 
OVERNIGHT. IN THE MEANTIME, THE CLEARING OF THE LOW CLOUDS AROUND 
THE FORECAST AREA, WILL MOVE THROUGH LATE THIS EVENING WHICH WILL 
TEMPORARILY ALLOW THE TEMPERATURES TO DROP BEFORE THE NEXT SURGE OF 
MOISTURE/CLOUDS MOVES IN POST 04Z. ONCE THE NEXT BATCH IS IN HERE, 
AND WITH THE TIGHTER SFC GRADIENT, WILL EXPECT THAT THE TEMPERATURES 
WILL BEGIN TO HEAD BACK UP OR AT THE VERY LEAST HOLD STEADY AS WE 
HEAD INTO SATURDAY MORNING. WITH THE FORMATION OF THE LOW CLOUDS, 
THE MODEL SOUNDINGS ARE MARGINAL WITH AN INCREASE IN MOISTURE WITH 
HEIGHT, SO WILL ALLOW FOR PATCHY DRIZZLE WHILE AREAS OF LIGHT FOG 
AROUND THE FORECAST AREA AGAIN SIMILAR TO THIS MORNING. HOWEVER, IT 
LOOKS LIKE AROUND 12Z THAT THE COLD FRONT WILL BE PUSHING THROUGH, 
SO THAT THERE COULD BE SOME THINNING OF THE CLOUDS, ESPECIALLY ALONG 
THE LAKE MICHIGAN SHORELINE.

.LONG TERM...(SATURDAY THROUGH FRIDAY)
ISSUED AT 351 PM EDT FRI OCT 24 2014

OVERVIEW: FOUR WAVE LONG WAVE PATTERN REMAINS IN PLACE TODAY WITH 
TROUGHINESS ACROSS THE FAR EASTERN PACIFIC AND STRONG JET ENERGY 
FLOWING INTO THE PACIFIC NORTHWEST...DOWNSTREAM RIDGING INTO THE 
CENTRAL CONUS. FLOW BECOMES A BIT MORE SPLIT ACROSS EASTERN 
NOAM...WITH AN OLD CUT-OFF FEATURE LIFTING NE ALONG THE ATLANTIC 
COAST INTO NEW ENGLAND. SPLIT SHORT WAVE ENERGY (THAT BROUGHT US 
ISOLATED SHOWERS OVERNIGHT) NOW EXITING THE GREAT LAKES WITH ONE 
PIECE MOVING UP THROUGH EASTERN CANADA AND ANOTHER MOVING DOWN 
THROUGH THE OHIO VALLEY TOWARD THE SE ATLANTIC STATES. AT THE 
SFC...NARROW RIDGE AXIS STRETCHES FROM THE GULF UP THROUGH THE GREAT 
LAKES. BUT ABUNDANT STRATUS SPANS THE MIDWEST INTO THE GREAT LAKES 
AND LOOKING TO IMPACT THE REGION FOR AT LEAST ANOTHER DAY. 

PATTERN EVOLUTION/FORECAST: OVERALL HEMISPHERIC FLOW PATTERN STILL 
EXPECTED TO FLATTEN OUT AND BECOME MORE PROGRESSIVE FOR THE NEXT 
SEVERAL DAYS...WITH A SERIES OF SHORT WAVE TROUGHS MOVING 
THROUGH/NEAR THE REGION THROUGH THE EXTENDED FORECAST PERIOD. 

BY LATE NEXT WEEK...HEMISPHERIC LONGWAVE PATTERN WAS FORECAST TO 
UNDERGO A RECONFIGURATION WITH A BIG PUSH OF COLD AIR AND LARGER 
SCALE TROUGHING DEVELOPING ACROSS EASTERN NOAM AND THE GREAT 
LAKES...RAISING THE POSSIBILITIES FOR OUR FIRST SNOW OF THIS SEASON. 
HOWEVER...RECENT EURO/GFS/GEM GUIDANCE SOLUTIONS HAVE BACKED OFF 
THIS IDEA...SOMEWHAT...AND INSTEAD HANG ON TO EASTERN PACIFIC 
TROUGHING WHILE MAINTAINING A BIT MORE PROGRESSIVE FLOW ACROSS THE 
CONUS. COLDER AIR DOES STILL MAKE A SOUTHWARD PUSH OUT OF THE ARCTIC 
NEXT WEEK...BUT TRENDS SUGGEST MORE OF A GLANCING BLOW OF COLD AIR 
FOR THE GREAT LAKES WHILE CORE OF COLDEST AIR SLIDES THROUGH EASTERN 
CANADA. BUT THERE IS STILL QUITE A BIT OF FORECAST UNCERTAINTY 
TOWARD THE END OF NEXT WEEK HOWEVER...AS GUIDANCE SOLUTIONS HAVE 
EXHIBITED A FAIR AMOUNT OF INCONSISTENCY.   

IN THE NEARER TERM...BENIGN WEATHER ANTICIPATED THROUGH THE WEEKEND 
WHILE LOW CLOUDS/FOG CONTINUE TO BE THE PRIMARY SHORT TERM FORECAST 
CONCERN. 

SATURDAY/SATURDAY NIGHT/SUNDAY...STRONG SHORT WAVE WORKING THROUGH  
SOUTH-CENTRAL CANADA TODAY WILL TAKE A DIP DOWN THROUGH THE NRN 
GREAT LAKES ON SATURDAY...WITH AN ATTENDING COLD FRONT DROPPING DOWN 
THROUGH THE STATE BY EVENING. VERY LITTLE ORGANIZED PRECIP 
ANTICIPATED WITH THIS SYSTEM AS STRONGER FORCING WILL RESIDE WELL 
NORTH OF THE GREAT LAKES AND ANTECEDENT AIRMASS ACROSS THE GREAT 
LAKES/MIDWEST IS FAIRLY DRY. ABOUT THE BEST CHANCE FOR ANY PRECIP 
WILL OCCUR ACROSS THE NRN PARTS OF THE CWA LATE TONIGHT THROUGH 
SATURDAY MORNING IN CLOSER PROXIMITY TO THE BETTER MOISTURE/ 
FORCING...ALTHOUGH THERE VERY WELL COULD BE SPOTTY RETURNS/SPRINKLES 
ROLLING THROUGH THE REGION WITH THE FRONT. HOWEVER...NEXT BATCH OF 
STRATUS ALREADY ACROSS IOWA/SRN MINNESOTA TODAY STILL LOOKING TO GET 
DRAWN UP ACROSS NRN MICHIGAN AHEAD OF THE FRONT TONIGHT INTO 
SATURDAY LEADING TO ANOTHER CLOUDY START TO THE DAY WITH DRIZZLE 
AGAIN POSSIBLE PARTICULARLY ACROSS THE HIGHER TERRAIN. GOING 
FORECAST ALREADY PAINTS THAT SCENARIO. 

BEHIND THE FRONT...GUIDANCE HAS TRENDED MUCH MORE AGGRESSIVE WITH 
MIXING AND DRYING THINGS OUT SATURDAY AFTERNOON/SATURDAY NIGHT AS A 
BIG RIDGE OF HIGH PRESSURE AND WEDGE OF DRY AIR BUILD OVER THE GREAT 
LAKES BY SUNDAY. FORECAST SOUNDINGS AND LOW LEVEL RH PROGS SUPPORT 
CLEARING SKIES THROUGH SATURDAY AFTERNOON WHILE BREEZY NW WINDS 
DEVELOP BEHIND THE FRONT AND PERSIST THROUGH SATURDAY NIGHT.    

SUNDAY/SUNDAY NIGHT...SFC HIGH PRESSURE AND DRY AIR ACROSS THE 
REGION WILL RESULT IN A DECENT DAY WITH DIMINISHING WINDS. A GOOD 
AMOUNT OF SUNSHINE ANTICIPATED...ALTHOUGH WITH NW FLOW AND COOL LOW 
LEVEL TEMPS...AM A BIT CONCERNED WE SEE A BIT MORE LAKE RESPONSE/ 
LAKE CLOUDS. THEN...A COOL NIGHT SUNDAY NIGHT WITH DIMINISHING  
WINDS AND MAINLY CLEAR SKIES.            

MONDAY THROUGH FRIDAY...AS MENTIONED ABOVE...FLOW BECOMES 
MORE PROGRESSIVE FOR MUCH OF NEXT WEEK BEFORE TRANSITIONING TO 
DEEPER TROUGHINESS ACROSS EASTERN NOAM HEADING INTO NEXT WEEKEND. 
ANOTHER STRONGER PACIFIC SHORT WAVE TROUGH ADVANCES THROUGH THE 
CONUS DURING THE TUESDAY INTO WEDNESDAY TIMEFRAME BRINGING A STRONG 
LOW PRESSURE SYSTEM AND COLD FRONT THROUGH THE REGION LATE TUESDAY 
AND ANOTHER SHOT OF CHILLY AIR FOR MIDWEEK. RAIN CHANCES START TO 
INCREASE LATE SUNDAY NIGHT THROUGH MONDAY AS WE GET INTO THE WARM 
ADVECTION FORCING PART OF THIS SYSTEM. BUT THE BEST RAIN CHANCES 
WILL COME MONDAY NIGHT THROUGH TUESDAY AS THE SFC/UPPER LOW AND 
FRONT ADVANCE THROUGH THE REGION. 

GRADUALLY DRIES OUT FOR WEDNESDAY AND THURSDAY. ALTHOUGH WITH COLDER 
AIR OVER THE LAKES (-2C TO -4C H8 TEMPS) AND DEEPER CYCLONIC FLOW/ 
MOISTURE ACROSS THE NRN LAKES THROUGH AT LEAST WEDNESDAY...W/NW FLOW 
LAKE EFFECT RAIN SHOWERS ARE A GOOD BET FOR WEDNESDAY. AFTER 
THAT...PERHAPS A BREAK/DRY DAY FOR THURSDAY. BUT AS MENTIONED 
ABOVE...EXPECT A BIGGER PUSH OF COLD AIR DOWN THROUGH CANADA AND 
TOWARD THE GREAT LAKES FOR THE END OF THE WEEK. JUST HOW MUCH COLD 
AIR GETS DOWN INTO THE GREAT LAKES IS STILL UP FOR DEBATE WITH 
GUIDANCE TRENDS NOW KEEPING THE COLDEST AIR UP THROUGH EASTERN 
CANADA. BUT COLDER NONETHELESS BY HALLOWEEN WITH LAKE EFFECT SHOWER 
POTENTIAL. HAVE KEPT SNOW OUT OF THE FORECAST FOR NRN LOWER MICHIGAN 
AT THIS POINT...BUT HAVE RAIN OR SNOW SHOWER WORDING IN EASTERN 
UPPER MICHIGAN THURSDAY NIGHT AND FRIDAY. 

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1154 PM EDT FRI OCT 24 2014

CIGS DECREASING TO MVFR/IFR OVERNIGHT INTO THE START OF SAT
MORNING...THEN QUICKLY TURNING BREEZY AND VFR.

COLD FRONT MOVING INTO WI...WILL CROSSING NORTHERN MI TOWARD
DAYBREAK. MVFR TO AT TIMES IFR CLOUDS WILL RETURN JUST AHEAD OF
THE FRONT. COULD BE A TOUCH OF -DZ AS WELL...ESPECIALLY NEAR LAKE
MI. MUCH DRIER AIR ARRIVES BEHIND THE FRONT SAT MORNING...WITH
VFR CONDITIONS BY NOON.

LIGHT WINDS TONIGHT...GUSTY W TO NW WINDS SATURDAY.

&&

.MARINE...
ISSUED AT 351 PM EDT FRI OCT 24 2014

WINDS OVERNIGHT WILL INCREASE ON LAKE MICHIGAN AS THE 
PRESSURE GRADIENT BEGINS TO TIGHTEN UP AHEAD OF THE SFC AND COLD 
FRONT THAT WILL MOVE THROUGH MICHIGAN ON MONDAY. WINDS ALONG THE 
LAKE MICHIGAN SHORELINE IN NW LOWER IS EXPECTED TO GUST TO 25 KNOTS 
AFTER 06Z, AND WAVES ARE EXPECTED TO BUILD TO SMALL CRAFT HEIGHTS (3 
TO 5 FEET) BY SATURDAY MORNING. DURING THE DAY ON SATURDAY THE WINDS 
WILL VEER TO THE NW AND INCREASE TO SMALL CRAFT CRITERIA GUSTS. 
EVENTUALLY, BY SATURDAY AFTERNOON, THE NW WINDS WILL INCREASE ON 
LAKE HURON AS WELL, ESPECIALLY ALONG THE AREA FROM THE MACKINAC 
BRIDGE TO NORTH POINT. THE WINDS WILL CONTINUE THROUGH SATURDAY 
NIGHT UNTIL THE SFC HIGH BUILDS INTO LAKE MICHIGAN AROUND 12Z 
SUNDAY. WINDS ARE EXPECTED TO DIMINISH THROUGH THE MORNING, AND THE 
WAVES SUBSIDE BY SUNDAY AFTERNOON. 


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT SATURDAY FOR LHZ345-
     347.
LM...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR LMZ341-342-
     344>346.
LS...NONE.

&&

$$

UPDATE...JZ
SYNOPSIS...AM
SHORT TERM...JL
LONG TERM...ADAM
AVIATION...JZ
MARINE...JL

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