Area Forecast Discussion
Issued by NWS Gaylord, MI

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000
FXUS63 KAPX 300833
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
433 AM EDT THU OCT 30 2014

.SYNOPSIS...
ISSUED AT 432 AM EDT THU OCT 30 2014

HIGH PRESSURE INCHING THROUGH THE WESTERN LAKES TONIGHT WILL BUILD
ACROSS MICHIGAN EARLY TODAY...BUT WITH SHOWERS INCREASING THIS
AFTERNOON AND 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.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 432 AM EDT THU OCT 30 2014

OVERVIEW: LARGER SCALE TROUGHING REMAINS ACROSS EASTERN NOAM THIS
MORNING WITH UPSTREAM RIDGING ACROSS THE WESTERN CONUS AND DEEP
UPPER LOW JUST OFF THE WEST COAST INTO THE GULF OF ALASKA. ONE PIECE
OF SHORT WAVE ENERGY AND ASSOCIATED WEAK LOW PRESSURE (APPARENT
REMNANTS OF HURRICANE ANA) IS NOW MOVING SOUTHEASTWARD INTO THE
MIDWEST. STRONGER SHORT WAVE ENERGY (AND OUR NEXT BIG SHOT OF COLD
AIR) DROPPING DOWN THROUGH CENTRAL CANADA. IN BETWEEN THESE TWO
SYSTEMS...ALREADY SEEING SOME MODEST FORCING ALONG THE TIGHTENING
THERMAL GRADIENT AND SPOTTY LIGHT PRECIP SPREADING INTO THE UPPER
MIDWEST AND FAR WESTERN GREAT LAKES. BUT CLOSER TO HOME...BROAD SFC
RIDGE AXIS STRETCHES FROM THE WESTERN GREAT LAKES DOWN THROUGH THE
MISSISSIPPI RIVER VALLEY AND HAS BROUGHT SOME DRYING AND BREAK IN
THE PRECIP FOR NRN MICHIGAN.

TODAY/TONIGHT...LITTLE HAS CHANGED WITH THE OVERALL EXPECTATIONS
WITH THIS UPCOMING SYSTEM. STRONG SHORT WAVE AND PLUNGE OF
SUBSTANTIALLY COLDER AIR OVER CENTRAL CANADA THIS MORNING WILL DROP
INTO THE FAR NRN LAKES REGION BY EVENING BEFORE CONTINUE TO DIG DOWN
THROUGH THE WESTERN GREAT LAKES TONIGHT. THIS WILL ULTIMATELY SPIN
UP A COMPACT SFC LOW OVER LOWER MICHIGAN THAT HELPS DRAG THAT COLDER
AIR INTO THE STATE LATE TONIGHT THROUGH FRIDAY. A VERY DYNAMIC
SYSTEM THAT WILL BRING US WIND AND COLDER TEMPS AND THE FIRST
ACCUMULATING SNOW OF THIS WINTER SEASON...JUST IN TIME FOR
HALLOWEEN.

AS FOR TODAY...RELATIVELY BENIGN WEATHER ANTICIPATED. HOWEVER...
AFOREMENTIONED MODEST FORCING ALREADY UNDERWAY ACROSS THE UPPER
MIDWEST/SRN CANADA WHERE UPPER HEIGHT FALLS ARE ALREADY TAKING SHAPE
AND THERMAL GRADIENT IS ALREADY GETTING SQUEEZED. THIS REGION OF
MODEST FORCING IS EXPECTED TO SPREAD ACROSS THE NRN GREAT LAKES
DURING THE COURSE OF THE DAY AND SHOULD BRING AN EXPANDING AREA OF
SHOWERS INTO THE NRN PARTS OF THE CWA. MAY ALSO SEE SOME RESIDUAL
LAKE EFFECT SHOWERS IMPACTING NW LOWER MICHIGAN AS WELL (SPOTTY
SHOWERS EVIDENT ON RADAR AROUND GRAND TRAVERSE BAY THIS
MORNING).

TONIGHT...REALLY GETS INTERESTING. POTENT SHORT WAVE AND PLUNGE OF
SUBSTANTIALLY COLD AIR DROPS DOWN THROUGH THE WESTERN GREAT
LAKES...SPINNING UP A COMPACT SFC LOW OVER LOWER MICHIGAN WITH
ATTENDING DEVELOPING COLD FRONT DROPPING DOWN THROUGH NRN MICHIGAN
LATE THIS EVENING AND OVERNIGHT. BULLSEYE OF DEEP LAYER QG-UPWARD
ASCENT DROPS DOWN INTO THE STATE WITH THE WAVE WHICH WILL RESULT IN
FLAT OUT CATEGORICAL PRECIP CHANCES ACROSS THE CWA. BUT AFTER
FROPA...GUSTY NORTHERLY WINDS WILL RAMP UP RATHER QUICKLY ESPECIALLY
ACROSS EASTERN UPPER AND NW LOWER MICHIGAN BY MORNING. BUT MORE
IMPORTANTLY...SUBSTANTIALLY COLDER AIR SLAMMING DOWN THROUGH THE
REGION WILL TURN PRECIP OVER TO SNOW ACROSS EASTERN UPPER MICHIGAN
BY LATE EVENING/EARLY OVERNIGHT AND ACROSS THE TIP OF THE MITT AND
PORTIONS OF NW LOWER MICHIGAN TOWARD MORNING (PARTICULARLY ACROSS
THE HIGHER TERRAIN). ACCUMULATIONS...SEEM MOST LIKELY ACROSS EASTERN
UPPER MICHIGAN WHERE AROUND AN INCH IS POSSIBLE. PRECIP CHANGE MAY
SIMPLY COME TO LATE ACROSS NRN LOWER MICHIGAN TO SEE ANY APPRECIABLE
ACCUMULATION...ALTHOUGH IF THE CHANGEOVER OCCURS EARLY ENOUGH AND/OR
IT SNOWS HARD ENOUGH...WE COULD SEE MORE THAN IS CURRENTLY FORECAST.

THUNDER CHANCES...OF COURSE A VERY DYNAMIC SYSTEM AND FORECAST
SOUNDING TEMP PROFILES FOLD OVER RATHER QUICKLY AS POCKET OF COLD
AIR COMES IN ALOFT...RESULTING IN SOME STEEPER LOW-MID LEVEL LAPSE
RATES. IT MAY BE A STRETCH...BUT WOULD NOT BE SURPRISED TO SEE SOME
THUNDER OVERNIGHT (AND INTO FRIDAY) AND HAVE ADDED THUNDER TO THE
FORECAST FOR NRN LOWER MICHIGAN.

&&

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 432 AM EDT THU OCT 30 2014

..."SCARY" COLD HALLOWEEN BUT THEN SOME MODERATION...

HIGH IMPACT WEATHER POTENTIAL: A BURST OF SNOW AND WIND HALLOWEEN
MORNING...AND A VERY COLD TRICK-OR-TREAT TIME. GALES EXPECTED ON
PARTS OF THE GREAT LAKES...WITH EVEN A PERIOD OF STORM FORCE WINDS
POSSIBLE...PARTICULARLY ON LAKE MICHIGAN. NOT MUCH EXPECTED
THEREAFTER.

PATTERN SYNOPSIS/EVOLUTION: QUITE THE PATTERN CHANGE UNDERWAY...
ALBEIT SOMEWHAT BRIEFLY...WITH STRONG JET ENERGY CURRENTLY HELPING
DIG TROUGHING THROUGH THE GULF OF ALASKA. THAT IN TURN IS LEADING TO
RAPID HEIGHT RISES ACROSS THE NORTHERN GREAT BASIC NORTHWARD THROUGH
THE CANADIAN ROCKIES...THUS ALLOWING FOR ALREADY QUITE STRONG VORT
ENERGY OVER FAR SOUTHWEST NUNAVUT TO DIG NEARLY DUE SOUTHWARD THE
PAST 12 HOURS. THIS EXACT SETUP WILL CONTINUE FOR THE NEXT 48
HOURS...EFFECTIVELY ALLOWING FOR TREMENDOUS TROUGH AMPLIFICATION
THROUGH THE GREAT LAKES FRIDAY...WITH THIS TROUGH ENDING UP WELL TO
OUR SOUTH TOWARD THE MID ATLANTIC STATES BY SATURDAY. THAT OVERALL
SETUP WILL FORCE THE COLDEST AIRMASS OF THE FALL SEASON SO FAR
THROUGH OUR AREA INTO THE WEEKEND...BUT WITH A SWITCH TO STRONGER
NORTH PACIFIC JET ENERGY FORCING THE WESTERN RIDGE TO BUILD BACK
TOWARD THE PLAINS/GREAT LAKES FOR A TIME INTO VERY EARLY NEXT WEEK.
THAT TOO WILL BE SHORT-LIVED (TIS THE TIME OF YEAR) AS THE PATTERN
REMAINS QUITE PROGRESSIVE...WITH RENEWED TROUGHING OVER THE PLAINS
BY MONDAY EVENTUALLY LIFTING THROUGH OUR AREA SOMETIME TOWARD MONDAY
NIGHT OR TUESDAY...WITH A VERY WAVY PATTERN EXPECTED THEREAFTER INTO
MUCH OF NEXT WEEK SUGGESTING A CLASSIC UP AND DOWN FALL WEATHER
REGIME FOR THE GREAT LAKES.

LET`S BREAK IT DOWN:

FRIDAY-FRIDAY NIGHT: ALL FOCUS OF THE FORECAST IS ON HERE. APPROACH
OF ABOVE-MENTIONED SHARPENING TROUGH WILL SHOVE A STRONG COLD FRONT
THROUGH NORTHERN MICHIGAN BY 15Z FRIDAY AT THE LATEST...WITH QUITE
THE PUSH OF COLDER AIR RUSHING IN ALOFT IN ITS WAKE (H8 TEMPS DIVING
TOWARD -10C OR COLDER THROUGH THE DAY). SUCH SHARP AMPLIFICATION OF
SAID TROUGHING ALOFT WILL INCITE A QUICK DEFORMATION FORCING
RESPONSE IMMEDIATELY IN THE POST FRONTAL ENVIRONMENT...CONTINUING TO
STRONGLY SUGGEST AN ENHANCED BAND OF PRECIPITATION BISECTING THE CWA
THROUGH MUCH OF FRIDAY MORNING INTO EARLY AFTERNOON...EASING SOUTH
WITH TIME AS MUCH DRIER AIR AND DEEPER LAYER SUBSIDENCE BUILDS SOUTH
AFTER 18Z. THE REAL KICKER WITH THIS SETUP IS THE POTENTIAL FOR A
BAND OF VERY HEAVY SNOW TO DEVELOP JUST BEHIND THE FRONT AS
THICKNESSES RAPIDLY COLLAPSE INTO THE BACKSIDE OF THE PRECIP SHIELD
AND STRONG LIFT COMPENSATES FOR AN INITIALLY WARMER BOUNDARY LAYER.
EVEN SEE SOME HINTS OF THE STRONGEST LIFT BISECTING THE DEEPENING
DGZ...IMPLYING THERE COULD BE A PERIOD OF SOME RATHER IMPRESSIVE
PRECIP RATES/FLAKE SIZE AS WE ACTIVATE DENDRITES. ADD INTO THAT A
LIKELY LAKE COMPONENT GIVEN SUCH STRONG COLD ADVECTION/FORCING AND
POTENTIALLY EVEN A CONVECTIVE COMPONENT WITH VERY STEEP LAPSE RATES
ROLLING THROUGH THE AREA...AND THE STAGE IS SET FOR WHAT COULD BE A
QUICK COUPLE OF INCHES FALLING BENEATH THE HEAVIEST PRECIP CORE...
PARTICULARLY INTO THE HIGHER TERRAIN OF NORTHERN LOWER WHERE THE
BEST FOCUS FOR PRECIP ENHANCEMENT COMES TOGETHER AND BOUNDARY LAYER
TEMPS ARE LIKELY TO FALL BELOW FREEZING VERY QUICKLY.

THERE WILL ALSO BE QUITE THE WIND COMPONENT WITH SAID COLD FRONT AS
A VERY TIGHT GRADIENT WORKS IN TANDEM WITH STRONG COLD ADVECTION AND
DEEP MIXING TO TAP INTO AN IMPRESSIVE CORE OF 40-50 KNOTS IN THE
925-850MB LAYER. FORECAST RAOBS FOR SEVERAL DAYS HAVE HINTED AT
SURFACE GUSTS PUSHING ADVISORY CRITERIA FOR A TIME INTO FRIDAY
AFTERNOON...ESPECIALLY CLOSER TO THE LAKE MICHIGAN COAST WHERE THE
STRONGEST WINDS ALOFT ARE ADVERTISED. THROW IN THAT WIND COMPONENT
WITH SNOW AND THERE COULD WELL BE SOME TRAVEL ISSUES WITH SNOWFALL
RATES OVERCOMING INITIALLY WARMER ROAD TEMPS. WILL CONTINUE TO
ADVERTISE THIS HARD IN THE HWO/WEB GRAPHICS AS IT WILL BE THE FIRST
SNOW OF THE SEASON AND THESE USUALLY CAUSE QUITE A FEW ISSUES.

SYNOPTIC SNOW WILL COME TO AN END QUICKLY FRIDAY AFTERNOON AS
FORCING WANES AND MOISTURE DEPTH SHRINKS CONSIDERABLY. AT THE SAME
TIME...CONTINUED COOLER AIR SLIDING IN ALOFT WILL ONLY GROW THE LAKE
INSTABILITY WITH DELTA T VALUES PUSHING 20C. LACK OF DEEPER MOISTURE
WILL HURT THE CAUSE BUT SUSPECT THERE WILL STILL BE LINGERING LAKE
SNOW SHOWERS HUGGING BOTH THE LAKE MICHIGAN AND LAKE HURON COASTS...
PERHAPS PUSHING A BIT MORE INTO NORTHEAST LOWER AS THE FLOW THERE IS
BACKED A BIT MORE NORTHEASTERLY. COVERAGE OF THOSE SHOULD SHRINK
INTO FRIDAY EVENING AND NIGHT...ESPECIALLY NEAR LAKE MICHIGAN AS
NORTH/NORTHEAST FLOW AIDS IN SHOVING BANDING OFFSHORE...BUT THAT
SAME REGIME SHOULD AT THE VERY LEAST HELP BUILD RENEWED CLOUD COVER
BACK THROUGH MUCH OF NORTHEAST LOWER AND THE HIGHER TERRAIN...WHERE
A COUPLE ADDITIONAL SNOW SHOWERS/FLURRIES REMAIN POSSIBLE RIGHT ON
THROUGH THE NIGHT.

SATURDAY-SUNDAY NIGHT: DEEPEST UPPER TROUGHING WILL DEPART TO THE
EAST AS ELONGATED LOW LEVEL RIDGING GRADUALLY WORKS OVERHEAD.
RESIDUAL LAKE INSTABILITY AND TRAPPED MOISTURE BENEATH A LOWERING
INVERSION ARGUES FOR PESKY STRATOCU HANGING TOUGH ACROSS MUCH OF
NORTHERN LOWER THROUGH EARLY AFTERNOON...BUT STRONG DRYING AND
WANING INSTABILITY SHOULD FAVOR QUICK CLEARING LATER IN THE DAY AND
OVERNIGHT...WITH LIGHT WINDS/DRY AIR FAVORING WHAT COULD BE SOME
QUITE CHILLY TEMPS. WOULDN`T BE SHOCKED TO SEE SOME OF THE USUAL
COLD SPOTS DIP INTO THE TEENS...ESPECIALLY CONSIDERING MANY SPOTS
WILL BE STRUGGLING THROUGH THE 30S DURING THE DAY.

CLOUDS WILL THICKEN THROUGH THE DAY SUNDAY AS WARM ADVECTION CRANKS
UP ALOFT...BUT WITH NO PRECIP THREAT GIVEN A VERY DRY SUB-750MB
LAYER. STRONGER PUSH OF WARM ADVECTION MAY DELIVER A COUPLE
SPRINKLES BY SUNDAY NIGHT BUT DOUBTFUL AS THE BEST ASCENT LIES OVER
THE SOUTHWEST LAKES.

MONDAY-WEDNESDAY: UPPER TROUGH OVER THE PLAINS WILL LIFT TOWARD THE
GREAT LAKES LATER MONDAY INTO TUESDAY...WITH RESULTANT INCREASING
CHANCES FOR SHOWERS ACROSS NORTHERN MICHIGAN THOUGH TIMING AND
COVERAGE IS A BIT IN QUESTION. TUESDAY NIGHT INTO WEDNESDAY LOOK DRY
AT THE MOMENT AS OUR NEXT BOUT OF UPPER TROUGHING WORKS OVERHEAD BUT
HIGH PRESSURE DOMINATES DOWN LOW. TEMPS MUCH MORE SEASONABLE WITH
HIGHS GENERALLY IN THE 40S AND LOWS IN THE 30S.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1145 PM EDT WED OCT 29 2014

LOW PRESSURE WILL DROP SE OUT OF CENTRAL CANADA OVERNIGHT AND
RAPIDLY DEEPEN AS IT HEADS INTO NRN MICHIGAN ON THURSDAY.
CHANCES OF RAIN SHOWERS WILL INCREASE AGAIN ON THURSDAY AS THAT
AREA OF LOW PRESSURE AND ASSOCIATED MOISTURE SLIDE INTO NRN
MICHIGAN. CONDITIONS WILL DETERIORATE TO SOLID MVFR...AND
EVENTUALLY IFR THURSDAY EVENING AS RAIN SHOWERS BECOME WIDESPREAD.
WINDS WILL REMAIN UNDER 10 KTS THRU THE FORECAST PERIOD.


&&

.MARINE...
ISSUED AT 432 AM EDT THU OCT 30 2014

A PERIOD OF LIGHTER WINDS IS ANTICIPATED TODAY AS HIGH PRESSURE
DRIFTS OVER THE WATERS. HOWEVER...A STRONG COLD FRONT WILL BLAST
THROUGH THE REGION LATE TONIGHT INTO EARLY FRIDAY MORNING...SHIFTING
WINDS NORTH TO NORTH/NORTHEASTERLY WITH INCREASING SPEEDS AS SOME
VERY COLD AIR ARRIVES AND DEEP MIXING ENSUES OVER THE WATERS. FULLY
ANTICIPATE 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 AS THE FRONT ARRIVES...WITH THUNDERSTORMS ALSO
POSSIBLE. 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...NONE.
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.

&&

$$

SYNOPSIS...LAWRENCE
SHORT TERM...ADAM
LONG TERM...LAWRENCE
AVIATION...MR
MARINE...LAWRENCE






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