002  
FXUS63 KAPX 310155  
AFDAPX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GAYLORD MI  
955 PM EDT THU OCT 30 2014  
   
SYNOPSIS
 
 
ISSUED AT 953 PM EDT THU OCT 30 2014  
 
SHOWERS WILL BE INCREASING TONIGHT AS A COLD FRONT APPROACHES. THAT  
FRONT WILL ARRIVE HERE EARLY FRIDAY...BRINGING A PERIOD OF RAIN  
CHANGING TO SNOW AS WELL AS WINDY AND MUCH COLDER WEATHER JUST IN  
TIME FOR HALLOWEEN. PRECIPITATION CHANCES WILL DWINDLE FRIDAY  
NIGHT...WITH CHILLY AND DRY CONDITIONS ANTICIPATED FOR THE UPCOMING  
WEEKEND.  
 

 
   
UPDATE
 
 
UPDATE ISSUED AT 853 PM EDT THU OCT 30 2014  
 
LIGHT RAIN HAS OVERSPREAD MUCH OF THE AREA THIS EVENING IN ADVANCE  
OF APPROACHING SHORTWAVE/STRONG COLD STILL POISED TO SWEEP INTO  
THE AREA OVERNIGHT. FROPA LOOKS TO BE AROUND 06Z OVER EASTERN  
UPPER MICHIGAN AND BETWEEN 09Z-12Z OVER NORTHERN LOWER. HAVE  
SLOWED DOWN THE RAIN TO SNOW CHANGEOVER SLIGHTLY BASED ON UPSTREAM  
OBS...BUT OVERALL TREND IS STILL FOR RAIN TO CHANGE TO SNOW OVER  
MUCH OF EASTERN UPPER AND THE HIGHER TERRAIN OF NORTHERN LOWER  
BEFORE SUNRISE.  
 
DECIDED TO EXTEND THE WIND ADVISORY NORTHWARD UP ALONG THE LAKE  
MICHIGAN COAST. CORE OF STRONGEST 925MB WINDS OF 45-55KTS MOVES  
ACROSS THAT AREA DURING THE MORNING HOURS. AND GIVEN THE  
DYNAMICS/FORCING ASSOCIATED WITH FRONT AND COLD AIR  
ADVECTION...WOULD EXPECT SOME 40-50 MPH WIND GUSTS.  
 

 
   
SHORT TERM
 
(THIS EVENING THROUGH TONIGHT)  
ISSUED AT 853 PM EDT THU OCT 30 2014  
 
FOCUS IN THE SHORT TERM IS WITH A STRONG SHORTWAVE TROUGH CURRENTLY  
JUST NW OF LAKE SUPERIOR THAT WILL DROP INTO THE BROAD UPPER TROUGH  
OVER THE ERN CONUS. AS IT DOES SO...THE SHORTWAVE WILL CLOSE OFF  
OVER IN BY 00Z SAT AFTER IT MOVES ACROSS THE FAR WRN CWA FRI  
MORNING. WHILE THE SFC LOW COMPONENT WILL BE WEAK AT ONLY  
1010MB...THE STRONG MID/UPPER LEVEL DYNAMICS AND SFC PRESSURE CHANGE  
DUE TO INCOMING 1035MB HIGH PRESSURE COMBINED WITH STRONG CAA BEHIND  
A STRONG SFC COLD FRONT WILL LEAD TO STRONG N-NNE WINDS. THE  
STRONGEST WINDS ARE EXPECTED OVER THE GREAT LAKES AND ADJACENT  
SHORELINES...ESPECIALLY THE LAKE MICHIGAN SHORELINE. A WIND ADVISORY  
HAS BEEN ISSUED FROM MANISTEE TO LEELANAU COUNTIES FROM 10Z FRI TO  
00Z SAT. INLAND...GUSTY WINDS ARE EXPECTED AS A CORE OF 35-45KT  
925-850MB WINDS MOVES OVERHEAD. THINK GUSTS WILL REMAIN BELOW WIND  
GUST CRITERIA INLAND...BUT IF MIXING IS ESPECIALLY STRONG AN  
ADVISORY MAY BE NEEDED.  
 
SCATTERED RAIN SHOWERS HAVE BEEN OBSERVED OVER THE CWA TODAY AS WEAK  
HEIGHT FALLS MOVE INTO THE AREA WITH WEAK SFC CYCLOGENESIS. THOSE  
SHOWERS SHOULD MOVE E THIS EVENING AS WIDESPREAD RAIN SHOWERS PUSH  
IN FROM THE NW ALONG AND AHEAD OF THE SHORTWAVE. THE COLD FRONT WILL  
MOVE INTO ERN UPPER MI AROUND 06Z FRI THEN NWRN LOWER MI SHORELINE  
AROUND 09Z...WITH THE FRONT MOVING SE OF THE CWA BY 15Z FRI. THE  
COLDER AIR /850MB TEMPS TO AROUND -10C/ SURGING IN BEHIND THE FRONT  
WILL LEAD INCREASED SNOW CHANCES. SNOW WILL BECOME THE PREDOMINANT  
PTYPE OVER THE ERN U.P. RIGHT BEHIND THE FRONT...WITH THE TRANSITION  
OVER NRN LOWER MI STARTING OVER THE HIGHER TERRAIN AND WORKER TO THE  
LOWER TERRAIN THROUGH THE DAY. ACCUMULATIONS WILL BE HIGHEST OVER  
ERN UPPER MI AND THE HIGHER TERRAIN OF NRN LOWER MI...WHERE AROUND 2  
INCHES OF SNOW IS EXPECTED. WHILE THE GROUND IS WARM...SOME SLUSHY  
ACCUMULATIONS ARE POSSIBLE ON ROADWAYS GIVEN THAT THE SNOW WILL FALL  
RELATIVELY HEAVY AT TIMES FOR A SHORT PERIOD. DID NOT GO WITH ANY  
WINTER HEADLINES AS SNOW AMOUNTS SHOULD BE LESS THAN ADVISORY  
CRITERIA. THE PRECIPITATION WILL CONTINUE AFTER THE SHORTWAVE  
PASSES...MAINLY IN N-NNE WIND UPSLOPE/LAKE EFFECT BELTS.  
HOWEVER...MUCH DRIER AIR/SUBSIDENCE WILL LEAD TO MORE RAPID  
DIMINISHING OF PRECIP FROM THE NW LATE IN THE DAY.  
   
LONG TERM
 
(FRIDAY THROUGH THURSDAY)  
ISSUED AT 853 PM EDT THU OCT 30 2014  
 
FRIDAY NIGHT WILL POSITION THE REGION BEHIND THE STRONG SHORTWAVE  
DIVING SOUTH THROUGH THE GREAT LAKES REGION TONIGHT INTO  
FRIDAY...LEAVING STRONG AND COLD NORTH-NORTHEASTERLY FLOW IN ITS  
WAKE FOR FRIDAY NIGHT INTO SATURDAY. WITH MIXING TO 800MB TEMPS  
AROUND -12C...DELTA-T VALUES WILL BE AT OR ABOVE 20 AT 00Z SATURDAY  
AND PROVIDE PLENTY OF OVER LAKE INSTABILITY FOR LAKE EFFECT SNOW.  
THESE FAVORABLE CONDITIONS WILL BE CONFINED TO MAINLY THE LATE  
AFTERNOON...BEFORE THE INFLUENCE OF THE UPPER RIDGE OVER THE  
NORTHERN PLAINS AND THE SURFACE HIGH MOVING INTO THE WESTERN GREAT  
LAKES INCREASES SUBSIDENCE AND LOWERS THE INVERSION OVER THE AREA.  
THESE DETRIMENTAL FEATURES TO LAKE EFFECT WILL TAKE HOLD FAIRLY  
QUICKLY EARLY IN THE EVENING AND WILL SHOW A VERY FAST DROP OFF TO  
THE LAKE EFFECT POPS OVER THE FAVORED LOCATIONS ALONG THE WESTERN  
SHORE OF NORTHERN LOWER MICHIGAN. OVER THE EASTERN AREAS...THE  
SLIGHTLY LATER ARRIVAL OF THE SUBSIDENCE AND DRY AIR ALOFT WILL  
ALLOW THE LAKE EFFECT SNOW TO LINGER A LITTLE LONGER AND WILL HAVE  
CHANCE POPS REMAINING INTO THE OVERNIGHT HOURS. WILL CONTINUE TO  
SLOWLY DIMINISH POPS INTO SATURDAY MORNING AS THE CLOUD DEPTH  
CONTINUES TO SHRINK. WHILE THE SNOW WILL COME TO AN END IN THE  
MORNING...EXPECT THE LAKE CLOUDS TO PERSIST OVER THE EAST INTO MID  
AFTERNOON. HIGHS ON SATURDAY WILL REBOUND SLIGHTLY BUT STILL STAY IN  
THE MID TO UPPER 30S.  
 
AS CLOUDS CLEAR OUT AND THE HIGH PRESSURE RIDGE MOVES DIRECTLY OVER  
LOWER MICHIGAN ON SATURDAY NIGHT...A GREAT RADIATIONAL COOLING  
NIGHT IS IN STORE AND WILL LEAD TO VERY COLD OVERNIGHT LOWS. WITH  
THE MAV GENERALLY PERFORMING WELL IN RADIATIONAL COOLING  
SITUATIONS...WILL FOLLOW THAT FOR LOWS AND HAVE VALUES IN THE UPPER  
TEENS AND LOWER 20S FOR LOCATIONS AWAY FROM THE GREAT LAKES  
SHORELINES. SOME LOCATIONS OVER WESTERN LOWER MICHIGAN COULD  
WARM SLIGHTLY LATE IN THE NIGHT AS HIGH CLOUDS BEGIN TO STREAM INTO  
THE AREA (AND CONTINUE INTO SUNDAY) AHEAD OF A WEAK SHORTAVE  
UNDERCUTTING THE UPPER RIDGE.  
 
THAT SHORTWAVE AND BROAD WARM AIR ADVECTION WILL PUSH THROUGH THE  
AREA ON SUNDAY NIGHT. AT THIS TIME...EXPECT MAINLY MID CLOUDS TO BE  
ASSOCIATED WITH THESE FEATURES BUT WOULDN/T BE SURPRISED TO SEE A  
FEW SPRINKLES AFFECTING THE WESTERN PART OF NORTHERN LOWER  
MICHIGAN. SHOULDN/T SEE MUCH MORE THAN THAT PRECIPITATION WISE DUE  
TO THE EXISTING LOW LEVEL DRY AIR FROM THE DEPARTING SURFACE HIGH.  
 
THE FIRST PART OF NEXT WEEK WILL BE CONTROLLED BY AN UPPER TROUGH  
LIFTING OUT OF THE WESTERN CONUS ON SUNDAY AND THROUGH THE NORTHERN  
PLAINS ON MONDAY. THIS WILL TRACK EAST THROUGH THE UPPER GREAT  
LAKES TUESDAY NIGHT. A SURFACE LOW ASSOCIATED WITH THIS FEATURE  
WILL LIFT NORTHEAST FROM THE NORTHERN PLAINS ON SUNDAY THROUGH LAKE  
WINNIPEG AND TO FAR NORTHERN ONTARIO BY 00Z WEDNESDAY. EXPECT MUCH  
OF MONDAY TO BE DRY AS THE UPPER RIDGE AXIS SLIDES OVER THE AREA.  
THE SOUTHWEST FLOW WILL ALLOW FOR WARMING ALOFT AND PRODUCE  
HIGHS IN THE UPPER 40S AND LOWER 50S. THAT SOUTHWESTERLY FLOW WILL  
SURGE ABUNDANT MOISTURE FROM THE PACIFIC INTO LOWER MICHIGAN MONDAY  
NIGHT INTO TUESDAY MORNING BEFORE THE COLD FRONT ASSOCIATED WITH  
THE LOW MOVES THROUGH ON TUESDAY. THERE ARE STILL DIFFERENCES IN  
THE MODELS ON 850-700MB FLOW DIRECTION...WHICH WILL CONTROL THE  
NORTHWARD EXTENT OF THE PRECIPITATION FOR MONDAY NIGHT INTO TUESDAY  
MORNING. 12Z GFS AND 00Z ECMWF ARE FOCUSING THE BEST PRECIPITATION  
OVER CENTRAL/SOUTHERN LOWER MICHIGAN...WHILE THE 00Z/12Z GEM IS  
SHOWING MORE SOUTH-SOUTHWEST FLOW AT 850-700MB AND PULLING THE  
PRECIPITATION FARTHER TO THE NORTH. WILL FOLLOW A BLEND OF THE  
GFS/ECMWF WITH A NORTHWEST TO SOUTHEAST GRADIENT TO THE POPS AND  
HAVE A FEW LIKELY VALUES RUNNING ALONG THE SOUTHEN PART OF THE CWA.  
 
ONCE THE COLD FRONT MOVES THROUGH ON TUESDAY...AREA WILL BE DRY  
SLOTTED FOR A PERIOD INTO TUESDAY NIGHT BEFORE MOISTURE WRAPS BACK  
AROUND AND INTO THE AREA AS THE UPPER TROUGH ROTATES THROUGH. WILL  
SHOW SOME POPS OVER THE EASTERN U.P. AS THAT DEEPER MOISTURE MOVES  
THROUGH TUESDAY NIGHT INTO WEDNESDAY MORNING AN KEEP MOSTLY CLOUDY  
SKIES THROUGH WEDNESDAY. WILL FOLLOW A GENERAL CONSENSUS FOR  
THURSDAY AS BOTH GFS/ECMWF ARE SHOWING ANOTHER SHORTWAVE OR LARGER  
UPPER TROUGH (12Z GFS) SLIDING SOUTHEAST THROUGH THE AREA.  
 

 
   
AVIATION
 
(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)  
ISSUED AT 853 PM EDT THU OCT 30 2014  
   
..STRONG NORTH WINDS DEVELOPING LATE TONIGHT INTO FRIDAY
 
 
A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA LATER TONIGHT  
ACCOMPANIED BY RAIN AND SNOW SHOWERS AND STRONG WINDS. WINDS WILL  
INCREASE FROM THE NORTH...WITH GUSTS OVER 30KTS POSSIBLE AFTER 10Z.  
CIGS WILL LOWER TO MVFR TONIGHT...WITH PERIODS OF IFR CIGS/VBSYS  
POSSIBLE FRIDAY MORNING WITHIN STRONGER RAIN/SNOWSHOWER ACTIVITY.  
THE PRECIPITATION WILL GRADUALLY END THROUGH MIDDAY FRIDAY BUT  
STRONG NORTH WINDS WILL CONTINUE. SLOWLY IMPROVING CONDITIONS LATE  
FRIDAY INTO FRIDAY NIGHT AS HIGH PRESSURE BEGINS TO MOVE INTO THE  
AREA. WINDS WILL GRADUALLY DIMINISH AND SKIES WILL BEGIN TO CLEAR.  
 

 
   
MARINE
 
 
ISSUED AT 853 PM EDT THU OCT 30 2014  
 
A WEAK LOW PRESSURE SYSTEM MOVING ACROSS UPPER MICHIGAN THIS  
AFTERNOON WILL STRENGTHEN AS IT MOVES SOUTHEAST THROUGH THE REST OF  
THE GREAT LAKES TONIGHT INTO FRIDAY. THAT LOW...IN COMBINATION WITH  
A STRONG HIGH IN CENTRAL CANADA AND THE NORTHERN PLAINS WILL LEAD TO  
GALE CONDITIONS FOR MANY OF THE LAKE MICHIGAN AND LAKE HURON  
NEARSHORE WATERS...WITH SMALL CRAFT ADVISORY CONDITIONS LIKELY  
ELSEWHERE FRIDAY INTO FRIDAY NIGHT. THERE COULD EVEN BE A BRIEF  
PERIOD OF STORM FORCE WINDS SOUTH OF GRAND TRAVERSE LIGHT ON  
FRIDAY...THOUGH THAT LOOKS VERY BRIEF. PERIODS OF RAIN WILL CHANGE  
OVER TO SNOW BEHIND THE FRONT. WINDS WILL GRADUALLY SUBSIDE INTO  
SATURDAY AND ESPECIALLY SATURDAY NIGHT INTO SUNDAY WITH THE ARRIVAL  
OF HIGH PRESSURE...BEFORE SOUTHERLY WINDS INCREASE ONCE AGAIN INTO  
THE EARLY WORK WEEK.  
 

 
   
APX WATCHES/WARNINGS/ADVISORIES
 
 
MI...WIND ADVISORY FROM 6 AM TO 8 PM EDT FRIDAY FOR MIZ016-019>021-  
025-026-031.  
 
LH...SMALL CRAFT ADVISORY FROM 5 AM FRIDAY TO 5 AM EDT SATURDAY FOR  
LHZ345-346.  
 
GALE WARNING FROM 8 AM FRIDAY TO 5 AM EDT SATURDAY FOR  
LHZ347>349.  
 
LM...SMALL CRAFT ADVISORY FROM 5 AM FRIDAY TO 5 AM EDT SATURDAY FOR  
LMZ341.  
 
GALE WARNING FROM 5 AM TO 11 PM EDT FRIDAY FOR LMZ323-342-  
344>346.  
 
LS...SMALL CRAFT ADVISORY FROM 5 AM FRIDAY TO 5 AM EDT SATURDAY FOR  
LSZ321-322.  
 

 
 

 
 
UPDATE...KEYSOR  
SYNOPSIS...TJL  
SHORT TERM...MQT  
LONG TERM...MQT  
AVIATION...KEYSOR  
MARINE...MQT  
 
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