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000
FXUS63 KDTX 231122
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
622 AM EST SUN NOV 23 2014

.AVIATION...

//DISCUSSION...

CONDITIONS TODAY LOOK TO BE A BIT VARIABLE...LOW VFR VS MVFR
CEILINGS...AS BACKING SURFACE WINDS OUT OF THE SOUTHEAST WILL TEND
TO DRY OUT THE LOW LEVELS...WHILE AREAS OF SHOWERS WORKING THROUGH
THE AREA WILL TEND TO MOISTEN AND SUPPRESS CEILINGS BACK DOWN INTO
MVFR CATEGORY. HIGHER CONFIDENCE IN THE FORECAST THIS EVENING AND
TONIGHT WITH INCREASING LOW LEVEL MOISTURE AND MODERATE RAIN LEADING
TO IFR CONDITIONS THROUGH MAJORITY OF THE NIGHT...AS DEEPENING LOW
PRESSURE TRACKS WEST OF SOUTHEAST MICHIGAN. AS THE LOW TRACKS
THROUGH THE NORTHERN GREAT LAKES TOMORROW...WINDS WILL SHIFT TO THE
SOUTHWEST AND BECOME STRONG DURING THE AFTERNOON HOURS...LIKELY
GUSTING ABOVE 35 KNOTS.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE

&&

.PREV DISCUSSION...ISSUED 320 AM EST SUN NOV 23 2014

SHORT TERM... TODAY AND TONIGHT

COPIOUS AMOUNT OF UPPER LEVEL ENERGY/PV WORKING THROUGH THE ROCKIES
THIS MORNING. MOISTURE LADEN UPPER LEVEL WAVE OVER EASTERN TEXAS
ALREADY BECOMING ABSORBED/CAPTURED WITHIN THE STRENGTHENING
SOUTHWEST FLOW OVER THE CENTRAL CONSUS. IMPRESSIVE 12 HR HEIGHT FALL
CENTER (-18 DAM) WILL MOVE OVER WESTERN OHIO VALLEY BY 12Z
MONDAY...SUPPORTING GOOD CYCLOGENSIS MOVING INTO THE CENTRAL GREAT
LAKES. THIS WILL ASSURE A SOAKING RAIN TONIGHT...WITH STRONG LOW
LEVEL JET/GOOD OVERRUNNING SET UP/LARGE SCALE ASCENT...AND 850 MB
DEW PTS OF 7-8 C TO WORK WITH. RAINFALL TOTALS AROUND 1 INCH WILL
LIKELY BE COMMON. A QUICK LOOK AT 6 HR FLOOD GUIDANCE SHOWS 2
INCH THRESHOLDS...AND DO THINK THE GROUND WILL THAW OUT ENOUGH
TODAY TO BE ABLE TO HANDLE THIS RAINFALL...AND NOT PLANNING ON
ISSUING A FLOOD WATCH DESPITE THE 3+ STANDARD ANOMALY WITH RESPECT
TO PW VALES.

A MILD START TO THE DAY...AS TEMPERATURE ARE CURRENTLY IN THE MID
40S TO AROUND 50 DEGREES. HOWEVER...WITH THE SURFACE/NEAR SURFACE
WINDS BACKING OUT OF THE SOUTHEAST TODAY...WOULD NOT EXPECT MUCH
MORE OF A RISE (LOWER 50S)...WITH TEMPS HOVERING IN THE UPPER 40S
TO LOWER 50S TONIGHT WITH RENEWED SURGE OF WARM AIR ARRIVING.

LONG TERM... MONDAY THROUGH SATURDAY

DYNAMIC MID LEVEL WAVE LOCKED ONTO THE EXIT REGION OF AN ACTIVE
UPPER JET OF NORTH PACIFIC ORIGIN WILL QUICKLY LIFT INTO THE GREAT
LAKES ON MONDAY...IMMEDIATELY BEHIND THE LEAD SYSTEM WORKING THROUGH
TONIGHT.  SOME DEGREE OF INTERACTION BETWEEN THESE PV FEATURES AND
ATTENDANT UPPER JET COUPLING WILL RESULT IN A STEADY STRENGTHENING
OF THE ASSOCIATED SURFACE LOW TRACKING FROM SOUTHERN LAKE MICHIGAN
TO JUST NORTH OF THE STRAITS THROUGH MONDAY.  THERE REMAINS SOME
VARIABILITY YET WITHIN THE 00Z MODEL GUIDANCE IN TERMS OF BOTH THE
STRENGTH AND FORWARD MOMENTEM OF THE KEY LOW LEVEL FEATURES HEADING
INTO MONDAY.  HOWEVER THE GUIDANCE ENVELOP CONTINUES TO CONTRACT
WITH EACH PROGRESSIVE MODEL CYCLE...LENDING INCREASING CONFIDENCE IN
THE DETAILS THROUGH THIS TIME.

BRIEF WINDOW OF DEEPER PRE-FRONTAL SOUTHWEST FLOW IN PLACE MONDAY
MORNING...TEMPERATURES LIKELY PEAKING IN THE LOWER 50S DURING THIS
TIME.  BRIEF SUBSIDENCE SUGGESTS A SMALL PAUSE IN SHOWER DEVELOPMENT
MID MORNING...BEFORE THE INBOUND MID LEVEL WAVE WORKS ACROSS LATE
MORNING/EARLY AFTERNOON.  STRONG SIGNAL OF FRONTAL CONVERGENCE
TUCKED BENEATH FAVORABLE UPPER JET DYNAMICS AND A PERIOD OF GOOD CVA
POINTS TO AN INCREASE IN SHOWER COVERAGE THROUGH THIS TIME.
DIMINISHING STABILITY THROUGH THE COLUMN COULD YIELD A FEW RUMBLES
OF THUNDER AS WELL.  MAIN FORECAST ELEMENT OF INTEREST REMAINS THE
WIND POTENTIAL AS STRONG COLD AIR ADVECTION ENSUES FROM MID
AFTERNOON INTO THE EVENING HOURS.  STRONG POST-FRONTAL SOUTHWEST
GRADIENT TAKES HOLD DURING THIS TIME...SUSTAINED SPEEDS INCREASING
INTO THE 25 MPH RANGE.  GUST POTENTIAL WILL CAPITILIZE ON A PERIOD
OF STRONG 280-285K ISENTROPIC DESCENT AND AT LEAST WEAK MIXING
POTENTIAL AS LAPSE RATES STEEPEN WITH THE ADVECTIVE PROCESS.  RECENT
GUIDANCE MAINTAINS WIND SPEEDS IN THE 40 KNOT RANGE AT 925 MB.  THIS
WOULD INDICATE GUSTS CLOSE TO OR AT A LOW END ADVISORY /40 TO 45
MPH/...GREATEST GUSTS CENTERED 21Z-02Z.

AGGRESSIVE COLD AIR ADVECTION BRINGS TEMPERATURES BACK INTO THE 30S
BY EARLY EVENING...A PLUMMETING FREEZING LEVEL REINTRODUCING THE
POTENTIAL FOR SNOW SHOWERS TO MIX IN DURING THIS TIME.  MODEST LAKE
MICHIGAN RESPONSE INITIALLY /LAKE INDUCED EQUILIBRIUM LEVELS BELOW
5000 FT/ WITH THE STRENGTH OF THE WIND FIELD LIKELY CONTRIBUTING TO
A LACK OF BETTER DOWNSTREAM ORGANIZATION.  THE MAIN SHORTWAVE
ANCHORING THE PRIMARY HEIGHT FALL AXIS WILL SETTLE THROUGH
OVERNIGHT...WHICH MAY HELP AUGMENT THE MOISTURE FLUX IN GENERATING
SOME LIGHT SNOWERS WITH MINOR ACCUMULATION.  LOW TEMPERATURES BOTTOM
OUT WITHIN THE 25 TO 30 DEGREE RANGE.

EXTENDED STRETCH OF BELOW NORMAL TEMPERATURES STARTING TUESDAY...
LINGERING LOW LEVEL THERMAL TROUGH /-12C AT 850 MB/ AND PLENTY OF
CLOUD COVER ENSURING HIGHS ARRIVE WITHIN A COUPLE DEGREE OF
FREEZING.  LOW LEVEL FLOW VEERS TO A WESTERLY COMPONENT DURING THE
DAY...A MORE FAVORABLE TRAJECTORY FOR GREATER DOWNSTREAM ADVANCEMENT
OF THE LAKE MICHIGAN MOISTURE PLUME AND SOME LOCALIZED CONVERGENCE.
THIS WILL MAINTAIN A CHANCE FOR SNOW SHOWERS THROUGH THE DIURNAL
HEATING CYCLE.

DRY AND COLD INTO WEDNESDAY UNDER LOWER AMPLITUDE RIDGING.  CLIPPER
SYSTEM ON TRACK TO LIFT ACROSS THE GREAT LAKES WEDNESDAY NIGHT AND
EARLY THURSDAY.  MODEST MOISTURE RECOVERY IMMEDIATELY IN ADVANCE OF
THIS SYSTEM WOULD SUPPORT A LIGHT ACCUMULATING SNOWFALL AS THE
COMPACT MID LEVEL DYNAMICS SWEEP ACROSS DURING THIS TIME. DAYTIME
HIGHS IN THE LOWER 30S BOTH WEDNESDAY AND THURSDAY.

MARINE...

MODERATE SOUTHERLY WINDS WILL REMAIN IN PLACE TODAY AND TONIGHT AS
STRENGTHENING LOW PRESSURE LIFTS INTO THE GREAT LAKES.  THE ARRIVAL
OF WARMER AIR IN ADVANCE OF THIS SYSTEM WILL CONTAIN THE GUST
POTENTIAL...WITH WINDS GENERALLY AT 15 TO 25 KNOTS THROUGH THIS
PERIOD.

THE LOW PRESSURE SYSTEM WILL LIFT ACROSS THE WESTERN AND NORTHERN
GREAT LAKES THROUGH MONDAY...SENDING A STRONG COLD FRONT ACROSS THE
AREA MONDAY AFTERNOON. GALE FORCE WINDS LOOK LIKELY BEHIND THE COLD
FRONT MONDAY AND MONDAY NIGHT AS A TIGHT PRESSURE GRADIENT DEVELOPS
AND MUCH COLDER AIR RUSHES INTO THE AREA...WITH GUSTS POTENTIAL IN
EXCESS OF 45 KNOTS.  THERE IS STILL SOME UNCERTAINTY WITH HOW MUCH
THIS SYSTEM WILL DEEPEN AND THE EXACT TRACK IT WILL TAKE ACROSS THE
GREAT LAKES. FURTHER ADJUSTMENT TO THE FORECAST IS POSSIBLE. IF THE
SYSTEM DEEPENS FURTHER THAN CURRENTLY ANTICIPATED...STORM FORCE WIND
GUSTS COULD DEVELOP OVER PORTIONS OF LAKE HURON. THOSE WITH
INTERESTS IN THE GREAT LAKES MONDAY AND MONDAY NIGHT SHOULD FOLLOW
CHANGES IN THE FORECAST CLOSELY. A STORM WATCH IS NOW IN EFFECT FOR
CENTRAL LAKE HURON...WHILE A GALE WATCH REMAINS IN EFFECT MONDAY AND
MONDAY NIGHT FOR ALL OTHER MARINE AREAS.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LHZ361-
     421-422-441>443-462>464.

     STORM WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LHZ362-
     363.

LAKE ST CLAIR...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LEZ444.

&&

$$

AVIATION.....SF
SHORT TERM...SF
LONG TERM....MR
MARINE.......MR

YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 230820
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
320 AM EST SUN NOV 23 2014

.SHORT TERM... TODAY AND TONIGHT

COPIOUS AMOUNT OF UPPER LEVEL ENERGY/PV WORKING THROUGH THE ROCKIES
THIS MORNING. MOISTURE LADEN UPPER LEVEL WAVE OVER EASTERN TEXAS
ALREADY BECOMING ABSORBED/CAPTURED WITHIN THE STRENGTHENING
SOUTHWEST FLOW OVER THE CENTRAL CONSUS. IMPRESSIVE 12 HR HEIGHT FALL
CENTER (-18 DAM) WILL MOVE OVER WESTERN OHIO VALLEY BY 12Z
MONDAY...SUPPORTING GOOD CYCLOGENSIS MOVING INTO THE CENTRAL GREAT
LAKES. THIS WILL ASSURE A SOAKING RAIN TONIGHT...WITH STRONG LOW
LEVEL JET/GOOD OVERRUNNING SET UP/LARGE SCALE ASCENT...AND 850 MB
DEW PTS OF 7-8 C TO WORK WITH. RAINFALL TOTALS AROUND 1 INCH WILL
LIKELY BE COMMON. A QUICK LOOK AT 6 HR FLOOD GUIDANCE SHOWS 2
INCH THRESHOLDS...AND DO THINK THE GROUND WILL THAW OUT ENOUGH
TODAY TO BE ABLE TO HANDLE THIS RAINFALL...AND NOT PLANNING ON
ISSUING A FLOOD WATCH DESPITE THE 3+ STANDARD ANOMALY WITH RESPECT
TO PW VALES.

A MILD START TO THE DAY...AS TEMPERATURE ARE CURRENTLY IN THE MID
40S TO AROUND 50 DEGREES. HOWEVER...WITH THE SURFACE/NEAR SURFACE
WINDS BACKING OUT OF THE SOUTHEAST TODAY...WOULD NOT EXPECT MUCH
MORE OF A RISE (LOWER 50S)...WITH TEMPS HOVERING IN THE UPPER 40S
TO LOWER 50S TONIGHT WITH RENEWED SURGE OF WARM AIR ARRIVING.

&&

.LONG TERM...

DYNAMIC MID LEVEL WAVE LOCKED ONTO THE EXIT REGION OF AN ACTIVE
UPPER JET OF NORTH PACIFIC ORIGIN WILL QUICKLY LIFT INTO THE GREAT
LAKES ON MONDAY...IMMEDIATELY BEHIND THE LEAD SYSTEM WORKING THROUGH
TONIGHT.  SOME DEGREE OF INTERACTION BETWEEN THESE PV FEATURES AND
ATTENDANT UPPER JET COUPLING WILL RESULT IN A STEADY STRENGTHENING
OF THE ASSOCIATED SURFACE LOW TRACKING FROM SOUTHERN LAKE MICHIGAN
TO JUST NORTH OF THE STRAITS THROUGH MONDAY.  THERE REMAINS SOME
VARIABILITY YET WITHIN THE 00Z MODEL GUIDANCE IN TERMS OF BOTH THE
STRENGTH AND FORWARD MOMENTEM OF THE KEY LOW LEVEL FEATURES HEADING
INTO MONDAY.  HOWEVER THE GUIDANCE ENVELOP CONTINUES TO CONTRACT
WITH EACH PROGRESSIVE MODEL CYCLE...LENDING INCREASING CONFIDENCE IN
THE DETAILS THROUGH THIS TIME.

BRIEF WINDOW OF DEEPER PRE-FRONTAL SOUTHWEST FLOW IN PLACE MONDAY
MORNING...TEMPERATURES LIKELY PEAKING IN THE LOWER 50S DURING THIS
TIME.  BRIEF SUBSIDENCE SUGGESTS A SMALL PAUSE IN SHOWER DEVELOPMENT
MID MORNING...BEFORE THE INBOUND MID LEVEL WAVE WORKS ACROSS LATE
MORNING/EARLY AFTERNOON.  STRONG SIGNAL OF FRONTAL CONVERGENCE
TUCKED BENEATH FAVORABLE UPPER JET DYNAMICS AND A PERIOD OF GOOD CVA
POINTS TO AN INCREASE IN SHOWER COVERAGE THROUGH THIS TIME.
DIMINISHING STABILITY THROUGH THE COLUMN COULD YIELD A FEW RUMBLES
OF THUNDER AS WELL.  MAIN FORECAST ELEMENT OF INTEREST REMAINS THE
WIND POTENTIAL AS STRONG COLD AIR ADVECTION ENSUES FROM MID
AFTERNOON INTO THE EVENING HOURS.  STRONG POST-FRONTAL SOUTHWEST
GRADIENT TAKES HOLD DURING THIS TIME...SUSTAINED SPEEDS INCREASING
INTO THE 25 MPH RANGE.  GUST POTENTIAL WILL CAPITILIZE ON A PERIOD
OF STRONG 280-285K ISENTROPIC DESCENT AND AT LEAST WEAK MIXING
POTENTIAL AS LAPSE RATES STEEPEN WITH THE ADVECTIVE PROCESS.  RECENT
GUIDANCE MAINTAINS WIND SPEEDS IN THE 40 KNOT RANGE AT 925 MB.  THIS
WOULD INDICATE GUSTS CLOSE TO OR AT A LOW END ADVISORY /40 TO 45
MPH/...GREATEST GUSTS CENTERED 21Z-02Z.

AGGRESSIVE COLD AIR ADVECTION BRINGS TEMPERATURES BACK INTO THE 30S
BY EARLY EVENING...A PLUMMETING FREEZING LEVEL REINTRODUCING THE
POTENTIAL FOR SNOW SHOWERS TO MIX IN DURING THIS TIME.  MODEST LAKE
MICHIGAN RESPONSE INITIALLY /LAKE INDUCED EQUILIBRIUM LEVELS BELOW
5000 FT/ WITH THE STRENGTH OF THE WIND FIELD LIKELY CONTRIBUTING TO
A LACK OF BETTER DOWNSTREAM ORGANIZATION.  THE MAIN SHORTWAVE
ANCHORING THE PRIMARY HEIGHT FALL AXIS WILL SETTLE THROUGH
OVERNIGHT...WHICH MAY HELP AUGMENT THE MOISTURE FLUX IN GENERATING
SOME LIGHT SNOWERS WITH MINOR ACCUMULATION.  LOW TEMPERATURES BOTTOM
OUT WITHIN THE 25 TO 30 DEGREE RANGE.

EXTENDED STRETCH OF BELOW NORMAL TEMPERATURES STARTING TUESDAY...
LINGERING LOW LEVEL THERMAL TROUGH /-12C AT 850 MB/ AND PLENTY OF
CLOUD COVER ENSURING HIGHS ARRIVE WITHIN A COUPLE DEGREE OF
FREEZING.  LOW LEVEL FLOW VEERS TO A WESTERLY COMPONENT DURING THE
DAY...A MORE FAVORABLE TRAJECTORY FOR GREATER DOWNSTREAM ADVANCEMENT
OF THE LAKE MICHIGAN MOISTURE PLUME AND SOME LOCALIZED CONVERGENCE.
THIS WILL MAINTAIN A CHANCE FOR SNOW SHOWERS THROUGH THE DIURNAL
HEATING CYCLE.

DRY AND COLD INTO WEDNESDAY UNDER LOWER AMPLITUDE RIDGING.  CLIPPER
SYSTEM ON TRACK TO LIFT ACROSS THE GREAT LAKES WEDNESDAY NIGHT AND
EARLY THURSDAY.  MODEST MOISTURE RECOVERY IMMEDIATELY IN ADVANCE OF
THIS SYSTEM WOULD SUPPORT A LIGHT ACCUMULATING SNOWFALL AS THE
COMPACT MID LEVEL DYNAMICS SWEEP ACROSS THROUGH THIS TIME.  DAYTIME
TEMPERATURE IN THE LOWER 30S BOTH WEDNESDAY AND THURSDAY.

&&

.MARINE...

MODERATE SOUTHERLY WINDS WILL REMAIN IN PLACE TODAY AND TONIGHT AS
STRENGTHENING LOW PRESSURE LIFTS INTO THE GREAT LAKES.  THE ARRIVAL
OF WARMER AIR IN ADVANCE OF THIS SYSTEM WILL CONTAIN THE GUST
POTENTIAL...WITH WINDS GENERALLY AT 15 TO 25 KNOTS THROUGH THIS
PERIOD.

THE LOW PRESSURE SYSTEM WILL LIFT ACROSS THE WESTERN AND NORTHERN
GREAT LAKES THROUGH MONDAY...SENDING A STRONG COLD FRONT ACROSS THE
AREA MONDAY AFTERNOON. GALE FORCE WINDS LOOK LIKELY BEHIND THE COLD
FRONT MONDAY AND MONDAY NIGHT AS A TIGHT PRESSURE GRADIENT DEVELOPS
AND MUCH COLDER AIR RUSHES INTO THE AREA...WITH GUSTS POTENTIAL IN
EXCESS OF 45 KNOTS.  THERE IS STILL SOME UNCERTAINTY WITH HOW MUCH
THIS SYSTEM WILL DEEPEN AND THE EXACT TRACK IT WILL TAKE ACROSS THE
GREAT LAKES. FURTHER ADJUSTMENT TO THE FORECAST IS POSSIBLE. IF THE
SYSTEM DEEPENS FURTHER THAN CURRENTLY ANTICIPATED...STORM FORCE WIND
GUSTS COULD DEVELOP OVER PORTIONS OF LAKE HURON. THOSE WITH
INTERESTS IN THE GREAT LAKES MONDAY AND MONDAY NIGHT SHOULD FOLLOW
CHANGES IN THE FORECAST CLOSELY. A STORM WATCH IS NOW IN EFFECT FOR
CENTRAL LAKE HURON...WHILE A GALE WATCH REMAINS IN EFFECT MONDAY AND
MONDAY NIGHT FOR ALL OTHER MARINE AREAS.

&&

.AVIATION...ISSUED 1148 PM EST SAT NOV 22 2014

//DISCUSSION...

MILD CONDITIONS WILL PREVAIL OVER THE TAF SITES AHEAD OF A
DEVELOPING LOW PRESSURE SYSTEM OUT OVER THE PLAINS. LOW LEVEL WIND
SHEAR EARLY THIS MORNING WILL CEASE SHORTLY AFTER SUNRISE WHEN THE
LOW LEVEL WINDS DECREASE. CEILINGS HAVE POPPED JUST ABOVE MVFR
ACROSS THE SOUTHERN TAF SITES...HOWEVER UPSTREAM OBSERVATIONS SHOW
MVFR CIGS SHOULD RETURN SUNDAY MORNING AS ADDITIONAL LOW LEVEL
MOISTURE ADVECTS IN. WITH THE LOSS OF SNOW COVER ACROSS MOST OF THE
SITES...VSBYS ARE NO LONGER EXPECTED TO BE RESTRICTED DUE TO
INTERACTIONS WITH THE SNOW COVER. A MARKED DECREASE IN CONDITIONS IS
EXPECTED SUNDAY EVENING AS THE AFOREMENTIONED LOW TRACKS OVER THE
WESTERN GREAT LAKES WITH A SLUG OF MODERATE RAIN SHOWERS EXPECTED TO
LOWER CONDITIONS TO A PREVAILING IFR AROUND 00Z AND CONTINUE THROUGH
MUCH OF SUNDAY NIGHT. PTYPE WILL BE ALL RAIN THROUGH THE TAF PERIOD
AS WE REMAIN IN THE WARM SECTOR THROUGH SUNDAY NIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE THROUGH SUNDAY
  NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LHZ361-
     421-422-441>443-462>464.

     STORM WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LHZ362-
     363.

LAKE ST CLAIR...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LEZ444.

&&

$$

SHORT TERM...SF
LONG TERM....MR
MARINE.......MR
AVIATION.....KURIMSKI


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 230820
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
320 AM EST SUN NOV 23 2014

.SHORT TERM... TODAY AND TONIGHT

COPIOUS AMOUNT OF UPPER LEVEL ENERGY/PV WORKING THROUGH THE ROCKIES
THIS MORNING. MOISTURE LADEN UPPER LEVEL WAVE OVER EASTERN TEXAS
ALREADY BECOMING ABSORBED/CAPTURED WITHIN THE STRENGTHENING
SOUTHWEST FLOW OVER THE CENTRAL CONSUS. IMPRESSIVE 12 HR HEIGHT FALL
CENTER (-18 DAM) WILL MOVE OVER WESTERN OHIO VALLEY BY 12Z
MONDAY...SUPPORTING GOOD CYCLOGENSIS MOVING INTO THE CENTRAL GREAT
LAKES. THIS WILL ASSURE A SOAKING RAIN TONIGHT...WITH STRONG LOW
LEVEL JET/GOOD OVERRUNNING SET UP/LARGE SCALE ASCENT...AND 850 MB
DEW PTS OF 7-8 C TO WORK WITH. RAINFALL TOTALS AROUND 1 INCH WILL
LIKELY BE COMMON. A QUICK LOOK AT 6 HR FLOOD GUIDANCE SHOWS 2
INCH THRESHOLDS...AND DO THINK THE GROUND WILL THAW OUT ENOUGH
TODAY TO BE ABLE TO HANDLE THIS RAINFALL...AND NOT PLANNING ON
ISSUING A FLOOD WATCH DESPITE THE 3+ STANDARD ANOMALY WITH RESPECT
TO PW VALES.

A MILD START TO THE DAY...AS TEMPERATURE ARE CURRENTLY IN THE MID
40S TO AROUND 50 DEGREES. HOWEVER...WITH THE SURFACE/NEAR SURFACE
WINDS BACKING OUT OF THE SOUTHEAST TODAY...WOULD NOT EXPECT MUCH
MORE OF A RISE (LOWER 50S)...WITH TEMPS HOVERING IN THE UPPER 40S
TO LOWER 50S TONIGHT WITH RENEWED SURGE OF WARM AIR ARRIVING.

&&

.LONG TERM...

DYNAMIC MID LEVEL WAVE LOCKED ONTO THE EXIT REGION OF AN ACTIVE
UPPER JET OF NORTH PACIFIC ORIGIN WILL QUICKLY LIFT INTO THE GREAT
LAKES ON MONDAY...IMMEDIATELY BEHIND THE LEAD SYSTEM WORKING THROUGH
TONIGHT.  SOME DEGREE OF INTERACTION BETWEEN THESE PV FEATURES AND
ATTENDANT UPPER JET COUPLING WILL RESULT IN A STEADY STRENGTHENING
OF THE ASSOCIATED SURFACE LOW TRACKING FROM SOUTHERN LAKE MICHIGAN
TO JUST NORTH OF THE STRAITS THROUGH MONDAY.  THERE REMAINS SOME
VARIABILITY YET WITHIN THE 00Z MODEL GUIDANCE IN TERMS OF BOTH THE
STRENGTH AND FORWARD MOMENTEM OF THE KEY LOW LEVEL FEATURES HEADING
INTO MONDAY.  HOWEVER THE GUIDANCE ENVELOP CONTINUES TO CONTRACT
WITH EACH PROGRESSIVE MODEL CYCLE...LENDING INCREASING CONFIDENCE IN
THE DETAILS THROUGH THIS TIME.

BRIEF WINDOW OF DEEPER PRE-FRONTAL SOUTHWEST FLOW IN PLACE MONDAY
MORNING...TEMPERATURES LIKELY PEAKING IN THE LOWER 50S DURING THIS
TIME.  BRIEF SUBSIDENCE SUGGESTS A SMALL PAUSE IN SHOWER DEVELOPMENT
MID MORNING...BEFORE THE INBOUND MID LEVEL WAVE WORKS ACROSS LATE
MORNING/EARLY AFTERNOON.  STRONG SIGNAL OF FRONTAL CONVERGENCE
TUCKED BENEATH FAVORABLE UPPER JET DYNAMICS AND A PERIOD OF GOOD CVA
POINTS TO AN INCREASE IN SHOWER COVERAGE THROUGH THIS TIME.
DIMINISHING STABILITY THROUGH THE COLUMN COULD YIELD A FEW RUMBLES
OF THUNDER AS WELL.  MAIN FORECAST ELEMENT OF INTEREST REMAINS THE
WIND POTENTIAL AS STRONG COLD AIR ADVECTION ENSUES FROM MID
AFTERNOON INTO THE EVENING HOURS.  STRONG POST-FRONTAL SOUTHWEST
GRADIENT TAKES HOLD DURING THIS TIME...SUSTAINED SPEEDS INCREASING
INTO THE 25 MPH RANGE.  GUST POTENTIAL WILL CAPITILIZE ON A PERIOD
OF STRONG 280-285K ISENTROPIC DESCENT AND AT LEAST WEAK MIXING
POTENTIAL AS LAPSE RATES STEEPEN WITH THE ADVECTIVE PROCESS.  RECENT
GUIDANCE MAINTAINS WIND SPEEDS IN THE 40 KNOT RANGE AT 925 MB.  THIS
WOULD INDICATE GUSTS CLOSE TO OR AT A LOW END ADVISORY /40 TO 45
MPH/...GREATEST GUSTS CENTERED 21Z-02Z.

AGGRESSIVE COLD AIR ADVECTION BRINGS TEMPERATURES BACK INTO THE 30S
BY EARLY EVENING...A PLUMMETING FREEZING LEVEL REINTRODUCING THE
POTENTIAL FOR SNOW SHOWERS TO MIX IN DURING THIS TIME.  MODEST LAKE
MICHIGAN RESPONSE INITIALLY /LAKE INDUCED EQUILIBRIUM LEVELS BELOW
5000 FT/ WITH THE STRENGTH OF THE WIND FIELD LIKELY CONTRIBUTING TO
A LACK OF BETTER DOWNSTREAM ORGANIZATION.  THE MAIN SHORTWAVE
ANCHORING THE PRIMARY HEIGHT FALL AXIS WILL SETTLE THROUGH
OVERNIGHT...WHICH MAY HELP AUGMENT THE MOISTURE FLUX IN GENERATING
SOME LIGHT SNOWERS WITH MINOR ACCUMULATION.  LOW TEMPERATURES BOTTOM
OUT WITHIN THE 25 TO 30 DEGREE RANGE.

EXTENDED STRETCH OF BELOW NORMAL TEMPERATURES STARTING TUESDAY...
LINGERING LOW LEVEL THERMAL TROUGH /-12C AT 850 MB/ AND PLENTY OF
CLOUD COVER ENSURING HIGHS ARRIVE WITHIN A COUPLE DEGREE OF
FREEZING.  LOW LEVEL FLOW VEERS TO A WESTERLY COMPONENT DURING THE
DAY...A MORE FAVORABLE TRAJECTORY FOR GREATER DOWNSTREAM ADVANCEMENT
OF THE LAKE MICHIGAN MOISTURE PLUME AND SOME LOCALIZED CONVERGENCE.
THIS WILL MAINTAIN A CHANCE FOR SNOW SHOWERS THROUGH THE DIURNAL
HEATING CYCLE.

DRY AND COLD INTO WEDNESDAY UNDER LOWER AMPLITUDE RIDGING.  CLIPPER
SYSTEM ON TRACK TO LIFT ACROSS THE GREAT LAKES WEDNESDAY NIGHT AND
EARLY THURSDAY.  MODEST MOISTURE RECOVERY IMMEDIATELY IN ADVANCE OF
THIS SYSTEM WOULD SUPPORT A LIGHT ACCUMULATING SNOWFALL AS THE
COMPACT MID LEVEL DYNAMICS SWEEP ACROSS THROUGH THIS TIME.  DAYTIME
TEMPERATURE IN THE LOWER 30S BOTH WEDNESDAY AND THURSDAY.

&&

.MARINE...

MODERATE SOUTHERLY WINDS WILL REMAIN IN PLACE TODAY AND TONIGHT AS
STRENGTHENING LOW PRESSURE LIFTS INTO THE GREAT LAKES.  THE ARRIVAL
OF WARMER AIR IN ADVANCE OF THIS SYSTEM WILL CONTAIN THE GUST
POTENTIAL...WITH WINDS GENERALLY AT 15 TO 25 KNOTS THROUGH THIS
PERIOD.

THE LOW PRESSURE SYSTEM WILL LIFT ACROSS THE WESTERN AND NORTHERN
GREAT LAKES THROUGH MONDAY...SENDING A STRONG COLD FRONT ACROSS THE
AREA MONDAY AFTERNOON. GALE FORCE WINDS LOOK LIKELY BEHIND THE COLD
FRONT MONDAY AND MONDAY NIGHT AS A TIGHT PRESSURE GRADIENT DEVELOPS
AND MUCH COLDER AIR RUSHES INTO THE AREA...WITH GUSTS POTENTIAL IN
EXCESS OF 45 KNOTS.  THERE IS STILL SOME UNCERTAINTY WITH HOW MUCH
THIS SYSTEM WILL DEEPEN AND THE EXACT TRACK IT WILL TAKE ACROSS THE
GREAT LAKES. FURTHER ADJUSTMENT TO THE FORECAST IS POSSIBLE. IF THE
SYSTEM DEEPENS FURTHER THAN CURRENTLY ANTICIPATED...STORM FORCE WIND
GUSTS COULD DEVELOP OVER PORTIONS OF LAKE HURON. THOSE WITH
INTERESTS IN THE GREAT LAKES MONDAY AND MONDAY NIGHT SHOULD FOLLOW
CHANGES IN THE FORECAST CLOSELY. A STORM WATCH IS NOW IN EFFECT FOR
CENTRAL LAKE HURON...WHILE A GALE WATCH REMAINS IN EFFECT MONDAY AND
MONDAY NIGHT FOR ALL OTHER MARINE AREAS.

&&

.AVIATION...ISSUED 1148 PM EST SAT NOV 22 2014

//DISCUSSION...

MILD CONDITIONS WILL PREVAIL OVER THE TAF SITES AHEAD OF A
DEVELOPING LOW PRESSURE SYSTEM OUT OVER THE PLAINS. LOW LEVEL WIND
SHEAR EARLY THIS MORNING WILL CEASE SHORTLY AFTER SUNRISE WHEN THE
LOW LEVEL WINDS DECREASE. CEILINGS HAVE POPPED JUST ABOVE MVFR
ACROSS THE SOUTHERN TAF SITES...HOWEVER UPSTREAM OBSERVATIONS SHOW
MVFR CIGS SHOULD RETURN SUNDAY MORNING AS ADDITIONAL LOW LEVEL
MOISTURE ADVECTS IN. WITH THE LOSS OF SNOW COVER ACROSS MOST OF THE
SITES...VSBYS ARE NO LONGER EXPECTED TO BE RESTRICTED DUE TO
INTERACTIONS WITH THE SNOW COVER. A MARKED DECREASE IN CONDITIONS IS
EXPECTED SUNDAY EVENING AS THE AFOREMENTIONED LOW TRACKS OVER THE
WESTERN GREAT LAKES WITH A SLUG OF MODERATE RAIN SHOWERS EXPECTED TO
LOWER CONDITIONS TO A PREVAILING IFR AROUND 00Z AND CONTINUE THROUGH
MUCH OF SUNDAY NIGHT. PTYPE WILL BE ALL RAIN THROUGH THE TAF PERIOD
AS WE REMAIN IN THE WARM SECTOR THROUGH SUNDAY NIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE THROUGH SUNDAY
  NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LHZ361-
     421-422-441>443-462>464.

     STORM WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LHZ362-
     363.

LAKE ST CLAIR...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LEZ444.

&&

$$

SHORT TERM...SF
LONG TERM....MR
MARINE.......MR
AVIATION.....KURIMSKI


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 230448
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1148 PM EST SAT NOV 22 2014


.AVIATION...

//DISCUSSION...

MILD CONDITIONS WILL PREVAIL OVER THE TAF SITES AHEAD OF A
DEVELOPING LOW PRESSURE SYSTEM OUT OVER THE PLAINS. LOW LEVEL WIND
SHEAR EARLY THIS MORNING WILL CEASE SHORTLY AFTER SUNRISE WHEN THE
LOW LEVEL WINDS DECREASE. CEILINGS HAVE POPPED JUST ABOVE MVFR
ACROSS THE SOUTHERN TAF SITES...HOWEVER UPSTREAM OBSERVATIONS SHOW
MVFR CIGS SHOULD RETURN SUNDAY MORNING AS ADDITIONAL LOW LEVEL
MOISTURE ADVECTS IN. WITH THE LOSS OF SNOW COVER ACROSS MOST OF THE
SITES...VSBYS ARE NO LONGER EXPECTED TO BE RESTRICTED DUE TO
INTERACTIONS WITH THE SNOW COVER. A MARKED DECREASE IN CONDITIONS IS
EXPECTED SUNDAY EVENING AS THE AFOREMENTIONED LOW TRACKS OVER THE
WESTERN GREAT LAKES WITH A SLUG OF MODERATE RAIN SHOWERS EXPECTED TO
LOWER CONDITIONS TO A PREVAILING IFR AROUND 00Z AND CONTINUE THROUGH
MUCH OF SUNDAY NIGHT. PTYPE WILL BE ALL RAIN THROUGH THE TAF PERIOD
AS WE REMAIN IN THE WARM SECTOR THROUGH SUNDAY NIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE THROUGH SUNDAY
  NIGHT.

&&

.PREV DISCUSSION...ISSUED 420 PM EST SAT NOV 22 2014

SHORT TERM... LATE AFTERNOON THROUGH TONIGHT

LOW PRESSURE DEVELOPING IN CENTRAL CANADA INTO THE NORTHERN PLAINS
STATES WILL MAINTAIN SOUTHERLY WIND AND A SUPPLY OF MILD AIR INTO SE
MICHIGAN THROUGH TONIGHT. AFTER A SLIGHT EARLY EVENING DROP BACK
TOWARD THE UPPER 30S...TEMPERATURES WILL EASILY BE ABLE TO REMAIN
STEADY OR SLOWLY RISE THROUGH THE LOWER AND MID 40S DURING THE
NIGHT. THIS MILD AIR IS ALSO MOISTURE LADEN WHICH WILL KEEP CLUSTERS
OF SHOWERS GOING AMID CLOUDY SKY WITH FOG AND DRIZZLE THROUGH THE
REGION.

MID AFTERNOON OBSERVATIONAL TRENDS FAVOR THE GREATEST COVERAGE OF
SHOWERS DURING LATE AFTERNOON THROUGH MID EVENING FOLLOWED BY A
BREAK DURING THE OVERNIGHT HOURS. SATELLITE AND MODEL ANALYSIS
FIELDS POINT TO ANOTHER WEAK WAVE ALOFT HELPING TO SUPPORT CLUSTERS
OF SHOWERS MOVING IN FROM NORTHERN INDIANA AND SW LOWER MICHIGAN.
THE SHORT WAVE FORCING WILL INTERACT WITH THE LOW LEVEL THETA-E
RIDGE BEING DRAWN INTO SE MICHIGAN AROUND THE 850 MB LEVEL. THE
ASSOCIATED MOISTURE TRANSPORT AND ELEVATED INSTABILITY IS MODEST
WHICH WILL LIMIT SHOWER INTENSITY...AND THE WAVE IS PROGRESSIVE
ENOUGH TO SLIDE THROUGH OUR AREA BY MIDNIGHT. THE PASSAGE OF THIS
FEATURE WILL THEN LIMIT PRECIPITATION TO PATCHY DRIZZLE WITHIN AREAS
OF FOG LIKELY TO FORM AS INCREASINGLY MILD AIR FLOWS OVER SNOW
COVERED GROUND. PLAN TO MONITOR OBSERVATIONAL TRENDS FOR DENSE FOG
POTENTIAL WHICH SHOULD BE LIMITED TO THE LAKE EFFECT ENHANCED M-59/I-
69 CORRIDOR AND POSSIBLY POINTS NORTH. SNOW COVER IS REPORTED TO BE
DIMINISHING RAPIDLY TO THE SOUTH THROUGH THE DETROIT METRO AREA
TOWARD THE OHIO BORDER.

LONG TERM...SUNDAY THROUGH NEXT SATURDAY

WARM AND RAINY PATTERN WILL CONTINUE SUNDAY AND EARLY MONDAY BEFORE
A COLD FRONT USHERS IN STRONG WINDS AND COLDER AIR LATER IN THE DAY.

LARGE UPPER TROUGH OVER THE PACIFIC NORTHWEST AND NORTHERN ROCKIES
WILL PROGRESS EAST TOWARDS THE GREAT LAKES...SCOOPING UP THE UPPER
LOW NOW SEEN ON WATER VAPOR OVER TEXAS IN THE PROCESS. THE REMNANTS
OF THE TEXAS WAVE LOOK TO LIFT NORTHWARD ACROSS LOWER MICHIGAN
SUNDAY NIGHT...WITH THE UPPER TROUGH AXIS FOLLOWING BY MONDAY NIGHT.
MODELS CONTINUE TO KEY IN ON A BAND OF ISENTROPIC LIFT PROGRESSING
NORTHWARD OVER SOUTHEAST MICHIGAN...WITH TIMING NOW RANGING FROM
MORNING TO AFTERNOON. THIS BAND OF ASCENT COMBINED WITH AMPLE
MOISTURE REMAINING OVER THE AREA SHOULD PROVIDE A GOOD COVERAGE OF
RAIN SHOWERS TOMORROW. OTHER CONCERN WILL BE CONTINUED WARM AIR
ADVECTION OVER THE COLD GROUND WHERE AT LEAST SOME SNOW COVER WILL
REMAIN. THIS COULD LEAD TO SOME FOG FORMATION...BUT THICKNESS MAY BE
ENOUGH TO HAVE AN IMPACT TO INTERESTS OTHER THAN AVIATION. BETTER
INFLUX OF MOISTURE AND ADDITIONAL WARM AIR LOOKS TO OCCUR LATER IN
THE DAY AND OVERNIGHT AS THE UPPER WAVE FROM TEXAS APPROACHES AND
THE LOW-LEVEL JET RAMPS UP OVER THE OHIO VALLEY AHEAD OF THE
ADVANCING UPPER TROUGH. PVA AHEAD OF THE APPROACHING WAVE COMBINED
WITH ASCENT ALONG THE WARM FRONT AND A COUPLED JET STRUCTURE SHOULD
PROVIDE DEEP LAYER FORCING. THIS WILL COMBINE WITH PW VALUES IN
EXCESS OF 1.0 INCHES TO PROVIDE A WIDESPREAD RAIN EVENT DURING THE
EVENING AND OVERNIGHT. QPF AMOUNTS LOOK TO RANGE BETWEEN 0.6 AND 1.0
INCH. FLOODING DOES NOT LOOK TO BE A CONCERN GIVEN LOW CURRENT LOW
RIVER LEVELS AND ONLY A SMALL AMOUNT OF SNOW COVER REMAINING.
TEMPERATURES WILL REMAIN VERY MILD...SUPPORTED BY H850 TEMPS
REACHING AROUND 8C IN THE WARM SECTOR. THIS SHOULD SUPPORT MAX TEMPS
IN THE UPPER 40S TO LOW 50S TOMORROW...WITH ONLY A SMALL DROP INTO
THE MID 40S FOR SUNDAY NIGHT.

MODELS SOLUTIONS CONTINUE TO DIVERGE WITH THE TRACK AND STRENGTH OF
THE SURFACE LOW AS IT LIFTS ACROSS WESTERN AND NORTHERN LOWER
MICHIGAN SUNDAY NIGHT INTO MONDAY. BIGGEST IMPLICATION WITH THIS IS
THE AFFECT ON AND UNCERTAINTY WITH THE WIND SPEED FORECAST. CURRENT
PREFERENCE GOES TO THE LAST FEW EURO/GEM SOLUTIONS DUE TO GOOD RUN
TO RUN CONSISTENCY AND GOOD OVERALL CONSENSUS WITHIN THE MODEL
GUIDANCE ENVELOPE. THIS HAS AN AVERAGE LOW PRESSURE OF 974MB. 12Z
NAM WAS NOT TOO FAR OFF THIS AND SHOWS GOOD DESCENT BEHIND THE COLD
FRONT ALONG ISENTROPIC SURFACES BETWEEN 280-290K (INTO THE GROUND).
THIS DESCENT COMBINED WITH STEEPENING LAPSE RATES/DEEPENING BOUNDARY
LAYER FROM STRONG COLD AIR ADVECTION...A TIGHT SURFACE PRESSURE
GRADIENT...AND A CORE OF 40-55 KNOT WINDS BETWEEN 900-800MB MAY
ALLOW VERY STRONG WIND GUSTS TO REACH THE SURFACE. CURRENT FORECAST
HIGHLIGHTS GUSTS 40 TO 45 MPH...WITH POTENTIAL TO REACH 50 MPH.
HEADLINES ARE A POSSIBILITY...BUT THERE IS STILL PLENTY OF TIME FOR
THINGS TO CHANGE. A FEW RUMBLES OF THUNDER MAY ALSO BE POSSIBLE
EARLY ON MONDAY IN THE WARM SECTOR AS INSTABILITY INCREASES...AND
POSSIBLY BECOMES SURFACE BASED. RAIN WILL CHANGE TO SNOW BEHIND THE
FRONT AS TEMPERATURES FALL DURING THE LATE AFTERNOON AND
EVENING...WITH LIGHT ACCUMULATIONS POSSIBLE IN THE EVENING AND THEN
OVERNIGHT AS LAKE EFFECT PROCESSES RAMP UP. DRIER AIR WILL FILTER
INTO THE REGION...POTENTIALLY CLEARING MOISTURE OUT OF THE DGZ IN
THE EVENING PER 12Z NAM. GEM/EURO TRY TO BRUSH THE NORTHWEST CORNER
OF THE FORECAST AREA WITH DEFORMATION LINGERING BEHIND THE DEPARTING
SYSTEM...SOMETHING TO KEEP AN EYE ON FOR THE SAGINAW VALLEY BUT
ACCUMULATIONS LOOK LIGHT AT THIS TIME.

LOW PRESSURE TRACKING NORTHEAST OF THE REGION WILL CONTINUE TO BRING
A LOW CHANCE FOR SNOW SHOWERS TO MICHIGAN ON TUESDAY. BREEZY
CONDITIONS WILL CONTINUE THROUGH THE DAY WITH GUSTS STILL IN THE 20
TO 30 MPH RANGE. HIGH PRESSURE CREEPING IN FROM THE SOUTHWEST WILL
BRING DRY CONDITIONS TO THE AREA...BUT ARCTIC AIR INTRUSION COMES
BACK IN PLACE WITH TEMPS 10 TO 15 DEGREES BELOW NORMAL. A CLIPPER
SYSTEM COULD BRING ACCUMULATING SNOW ON THANKSGIVING...MORE DETAILS
WHEN NWP COMES CLOSER TO A CONSENSUS.

MARINE...

SOUTHWEST WINDS WILL CONTINUE TO DECREASE THROUGH THE EARLY EVENING
ACROSS THE CENTRAL GREAT LAKES...ALLOWING WINDS WAVES OVER LAKE
HURON TO GRADUALLY SUBSIDE. WINDS WILL SHIFT MORE SOUTHERLY SUNDAY
AND SUNDAY NIGHT AS A LARGE LOW PRESSURE SYSTEM BEGINS TO LIFT
TOWARDS THE AREA FROM THE PLAINS. WARMER AIR WILL ALSO CONTINUE TO
SURGE INTO THE AREA...PROVIDING A FAIRLY STABLE ENVIRONMENT OVER THE
WARM LAKE WATERS. THIS SHOULD HELP LIMIT GUSTS TO THE 15 TO 25 KNOT
RANGE SUNDAY AND SUNDAY NIGHT.

THE LOW PRESSURE SYSTEM WILL LIFT ACROSS THE WESTERN AND NORTHERN
GREAT LAKES SUNDAY NIGHT THROUGH MONDAY...SENDING A STRONG COLD
FRONT ACROSS THE AREA MONDAY AFTERNOON. GALE FORCE WINDS LOOK LIKELY
BEHIND THE COLD FRONT MONDAY AND MONDAY NIGHT AS A TIGHT PRESSURE
GRADIENT DEVELOPS AND MUCH COLDER AIR RUSHES INTO THE AREA...WITH
POTENTIAL FOR WIND GUSTS TO EXCEED 45 KNOTS. THERE IS STILL SOME
UNCERTAINTY WITH HOW MUCH THIS SYSTEM WILL DEEPEN AND THE EXACT
TRACK IT WILL TAKE ACROSS THE GREAT LAKES. FURTHER ADJUSTMENT TO THE
FORECAST IS POSSIBLE. IF THE SYSTEM DEEPENS FURTHER THAN CURRENTLY
ANTICIPATED...STORM FORCE WIND GUSTS COULD DEVELOP OVER PORTIONS OF
LAKE HURON. THOSE WITH INTERESTS IN THE GREAT LAKES MONDAY AND
MONDAY NIGHT SHOULD FOLLOW CHANGES IN THE FORECAST CLOSELY. A GALE
WATCH IS NOW IN EFFECT MONDAY AND MONDAY NIGHT FOR ALL MARINE AREAS.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR
     LHZ361>363-421-422-441>443-462>464.

LAKE ST CLAIR...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LEZ444.

&&

$$

AVIATION.....KURIMSKI
SHORT TERM...BT
LONG TERM....HLO/MM
MARINE.......HLO


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 230448
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1148 PM EST SAT NOV 22 2014


.AVIATION...

//DISCUSSION...

MILD CONDITIONS WILL PREVAIL OVER THE TAF SITES AHEAD OF A
DEVELOPING LOW PRESSURE SYSTEM OUT OVER THE PLAINS. LOW LEVEL WIND
SHEAR EARLY THIS MORNING WILL CEASE SHORTLY AFTER SUNRISE WHEN THE
LOW LEVEL WINDS DECREASE. CEILINGS HAVE POPPED JUST ABOVE MVFR
ACROSS THE SOUTHERN TAF SITES...HOWEVER UPSTREAM OBSERVATIONS SHOW
MVFR CIGS SHOULD RETURN SUNDAY MORNING AS ADDITIONAL LOW LEVEL
MOISTURE ADVECTS IN. WITH THE LOSS OF SNOW COVER ACROSS MOST OF THE
SITES...VSBYS ARE NO LONGER EXPECTED TO BE RESTRICTED DUE TO
INTERACTIONS WITH THE SNOW COVER. A MARKED DECREASE IN CONDITIONS IS
EXPECTED SUNDAY EVENING AS THE AFOREMENTIONED LOW TRACKS OVER THE
WESTERN GREAT LAKES WITH A SLUG OF MODERATE RAIN SHOWERS EXPECTED TO
LOWER CONDITIONS TO A PREVAILING IFR AROUND 00Z AND CONTINUE THROUGH
MUCH OF SUNDAY NIGHT. PTYPE WILL BE ALL RAIN THROUGH THE TAF PERIOD
AS WE REMAIN IN THE WARM SECTOR THROUGH SUNDAY NIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE THROUGH SUNDAY
  NIGHT.

&&

.PREV DISCUSSION...ISSUED 420 PM EST SAT NOV 22 2014

SHORT TERM... LATE AFTERNOON THROUGH TONIGHT

LOW PRESSURE DEVELOPING IN CENTRAL CANADA INTO THE NORTHERN PLAINS
STATES WILL MAINTAIN SOUTHERLY WIND AND A SUPPLY OF MILD AIR INTO SE
MICHIGAN THROUGH TONIGHT. AFTER A SLIGHT EARLY EVENING DROP BACK
TOWARD THE UPPER 30S...TEMPERATURES WILL EASILY BE ABLE TO REMAIN
STEADY OR SLOWLY RISE THROUGH THE LOWER AND MID 40S DURING THE
NIGHT. THIS MILD AIR IS ALSO MOISTURE LADEN WHICH WILL KEEP CLUSTERS
OF SHOWERS GOING AMID CLOUDY SKY WITH FOG AND DRIZZLE THROUGH THE
REGION.

MID AFTERNOON OBSERVATIONAL TRENDS FAVOR THE GREATEST COVERAGE OF
SHOWERS DURING LATE AFTERNOON THROUGH MID EVENING FOLLOWED BY A
BREAK DURING THE OVERNIGHT HOURS. SATELLITE AND MODEL ANALYSIS
FIELDS POINT TO ANOTHER WEAK WAVE ALOFT HELPING TO SUPPORT CLUSTERS
OF SHOWERS MOVING IN FROM NORTHERN INDIANA AND SW LOWER MICHIGAN.
THE SHORT WAVE FORCING WILL INTERACT WITH THE LOW LEVEL THETA-E
RIDGE BEING DRAWN INTO SE MICHIGAN AROUND THE 850 MB LEVEL. THE
ASSOCIATED MOISTURE TRANSPORT AND ELEVATED INSTABILITY IS MODEST
WHICH WILL LIMIT SHOWER INTENSITY...AND THE WAVE IS PROGRESSIVE
ENOUGH TO SLIDE THROUGH OUR AREA BY MIDNIGHT. THE PASSAGE OF THIS
FEATURE WILL THEN LIMIT PRECIPITATION TO PATCHY DRIZZLE WITHIN AREAS
OF FOG LIKELY TO FORM AS INCREASINGLY MILD AIR FLOWS OVER SNOW
COVERED GROUND. PLAN TO MONITOR OBSERVATIONAL TRENDS FOR DENSE FOG
POTENTIAL WHICH SHOULD BE LIMITED TO THE LAKE EFFECT ENHANCED M-59/I-
69 CORRIDOR AND POSSIBLY POINTS NORTH. SNOW COVER IS REPORTED TO BE
DIMINISHING RAPIDLY TO THE SOUTH THROUGH THE DETROIT METRO AREA
TOWARD THE OHIO BORDER.

LONG TERM...SUNDAY THROUGH NEXT SATURDAY

WARM AND RAINY PATTERN WILL CONTINUE SUNDAY AND EARLY MONDAY BEFORE
A COLD FRONT USHERS IN STRONG WINDS AND COLDER AIR LATER IN THE DAY.

LARGE UPPER TROUGH OVER THE PACIFIC NORTHWEST AND NORTHERN ROCKIES
WILL PROGRESS EAST TOWARDS THE GREAT LAKES...SCOOPING UP THE UPPER
LOW NOW SEEN ON WATER VAPOR OVER TEXAS IN THE PROCESS. THE REMNANTS
OF THE TEXAS WAVE LOOK TO LIFT NORTHWARD ACROSS LOWER MICHIGAN
SUNDAY NIGHT...WITH THE UPPER TROUGH AXIS FOLLOWING BY MONDAY NIGHT.
MODELS CONTINUE TO KEY IN ON A BAND OF ISENTROPIC LIFT PROGRESSING
NORTHWARD OVER SOUTHEAST MICHIGAN...WITH TIMING NOW RANGING FROM
MORNING TO AFTERNOON. THIS BAND OF ASCENT COMBINED WITH AMPLE
MOISTURE REMAINING OVER THE AREA SHOULD PROVIDE A GOOD COVERAGE OF
RAIN SHOWERS TOMORROW. OTHER CONCERN WILL BE CONTINUED WARM AIR
ADVECTION OVER THE COLD GROUND WHERE AT LEAST SOME SNOW COVER WILL
REMAIN. THIS COULD LEAD TO SOME FOG FORMATION...BUT THICKNESS MAY BE
ENOUGH TO HAVE AN IMPACT TO INTERESTS OTHER THAN AVIATION. BETTER
INFLUX OF MOISTURE AND ADDITIONAL WARM AIR LOOKS TO OCCUR LATER IN
THE DAY AND OVERNIGHT AS THE UPPER WAVE FROM TEXAS APPROACHES AND
THE LOW-LEVEL JET RAMPS UP OVER THE OHIO VALLEY AHEAD OF THE
ADVANCING UPPER TROUGH. PVA AHEAD OF THE APPROACHING WAVE COMBINED
WITH ASCENT ALONG THE WARM FRONT AND A COUPLED JET STRUCTURE SHOULD
PROVIDE DEEP LAYER FORCING. THIS WILL COMBINE WITH PW VALUES IN
EXCESS OF 1.0 INCHES TO PROVIDE A WIDESPREAD RAIN EVENT DURING THE
EVENING AND OVERNIGHT. QPF AMOUNTS LOOK TO RANGE BETWEEN 0.6 AND 1.0
INCH. FLOODING DOES NOT LOOK TO BE A CONCERN GIVEN LOW CURRENT LOW
RIVER LEVELS AND ONLY A SMALL AMOUNT OF SNOW COVER REMAINING.
TEMPERATURES WILL REMAIN VERY MILD...SUPPORTED BY H850 TEMPS
REACHING AROUND 8C IN THE WARM SECTOR. THIS SHOULD SUPPORT MAX TEMPS
IN THE UPPER 40S TO LOW 50S TOMORROW...WITH ONLY A SMALL DROP INTO
THE MID 40S FOR SUNDAY NIGHT.

MODELS SOLUTIONS CONTINUE TO DIVERGE WITH THE TRACK AND STRENGTH OF
THE SURFACE LOW AS IT LIFTS ACROSS WESTERN AND NORTHERN LOWER
MICHIGAN SUNDAY NIGHT INTO MONDAY. BIGGEST IMPLICATION WITH THIS IS
THE AFFECT ON AND UNCERTAINTY WITH THE WIND SPEED FORECAST. CURRENT
PREFERENCE GOES TO THE LAST FEW EURO/GEM SOLUTIONS DUE TO GOOD RUN
TO RUN CONSISTENCY AND GOOD OVERALL CONSENSUS WITHIN THE MODEL
GUIDANCE ENVELOPE. THIS HAS AN AVERAGE LOW PRESSURE OF 974MB. 12Z
NAM WAS NOT TOO FAR OFF THIS AND SHOWS GOOD DESCENT BEHIND THE COLD
FRONT ALONG ISENTROPIC SURFACES BETWEEN 280-290K (INTO THE GROUND).
THIS DESCENT COMBINED WITH STEEPENING LAPSE RATES/DEEPENING BOUNDARY
LAYER FROM STRONG COLD AIR ADVECTION...A TIGHT SURFACE PRESSURE
GRADIENT...AND A CORE OF 40-55 KNOT WINDS BETWEEN 900-800MB MAY
ALLOW VERY STRONG WIND GUSTS TO REACH THE SURFACE. CURRENT FORECAST
HIGHLIGHTS GUSTS 40 TO 45 MPH...WITH POTENTIAL TO REACH 50 MPH.
HEADLINES ARE A POSSIBILITY...BUT THERE IS STILL PLENTY OF TIME FOR
THINGS TO CHANGE. A FEW RUMBLES OF THUNDER MAY ALSO BE POSSIBLE
EARLY ON MONDAY IN THE WARM SECTOR AS INSTABILITY INCREASES...AND
POSSIBLY BECOMES SURFACE BASED. RAIN WILL CHANGE TO SNOW BEHIND THE
FRONT AS TEMPERATURES FALL DURING THE LATE AFTERNOON AND
EVENING...WITH LIGHT ACCUMULATIONS POSSIBLE IN THE EVENING AND THEN
OVERNIGHT AS LAKE EFFECT PROCESSES RAMP UP. DRIER AIR WILL FILTER
INTO THE REGION...POTENTIALLY CLEARING MOISTURE OUT OF THE DGZ IN
THE EVENING PER 12Z NAM. GEM/EURO TRY TO BRUSH THE NORTHWEST CORNER
OF THE FORECAST AREA WITH DEFORMATION LINGERING BEHIND THE DEPARTING
SYSTEM...SOMETHING TO KEEP AN EYE ON FOR THE SAGINAW VALLEY BUT
ACCUMULATIONS LOOK LIGHT AT THIS TIME.

LOW PRESSURE TRACKING NORTHEAST OF THE REGION WILL CONTINUE TO BRING
A LOW CHANCE FOR SNOW SHOWERS TO MICHIGAN ON TUESDAY. BREEZY
CONDITIONS WILL CONTINUE THROUGH THE DAY WITH GUSTS STILL IN THE 20
TO 30 MPH RANGE. HIGH PRESSURE CREEPING IN FROM THE SOUTHWEST WILL
BRING DRY CONDITIONS TO THE AREA...BUT ARCTIC AIR INTRUSION COMES
BACK IN PLACE WITH TEMPS 10 TO 15 DEGREES BELOW NORMAL. A CLIPPER
SYSTEM COULD BRING ACCUMULATING SNOW ON THANKSGIVING...MORE DETAILS
WHEN NWP COMES CLOSER TO A CONSENSUS.

MARINE...

SOUTHWEST WINDS WILL CONTINUE TO DECREASE THROUGH THE EARLY EVENING
ACROSS THE CENTRAL GREAT LAKES...ALLOWING WINDS WAVES OVER LAKE
HURON TO GRADUALLY SUBSIDE. WINDS WILL SHIFT MORE SOUTHERLY SUNDAY
AND SUNDAY NIGHT AS A LARGE LOW PRESSURE SYSTEM BEGINS TO LIFT
TOWARDS THE AREA FROM THE PLAINS. WARMER AIR WILL ALSO CONTINUE TO
SURGE INTO THE AREA...PROVIDING A FAIRLY STABLE ENVIRONMENT OVER THE
WARM LAKE WATERS. THIS SHOULD HELP LIMIT GUSTS TO THE 15 TO 25 KNOT
RANGE SUNDAY AND SUNDAY NIGHT.

THE LOW PRESSURE SYSTEM WILL LIFT ACROSS THE WESTERN AND NORTHERN
GREAT LAKES SUNDAY NIGHT THROUGH MONDAY...SENDING A STRONG COLD
FRONT ACROSS THE AREA MONDAY AFTERNOON. GALE FORCE WINDS LOOK LIKELY
BEHIND THE COLD FRONT MONDAY AND MONDAY NIGHT AS A TIGHT PRESSURE
GRADIENT DEVELOPS AND MUCH COLDER AIR RUSHES INTO THE AREA...WITH
POTENTIAL FOR WIND GUSTS TO EXCEED 45 KNOTS. THERE IS STILL SOME
UNCERTAINTY WITH HOW MUCH THIS SYSTEM WILL DEEPEN AND THE EXACT
TRACK IT WILL TAKE ACROSS THE GREAT LAKES. FURTHER ADJUSTMENT TO THE
FORECAST IS POSSIBLE. IF THE SYSTEM DEEPENS FURTHER THAN CURRENTLY
ANTICIPATED...STORM FORCE WIND GUSTS COULD DEVELOP OVER PORTIONS OF
LAKE HURON. THOSE WITH INTERESTS IN THE GREAT LAKES MONDAY AND
MONDAY NIGHT SHOULD FOLLOW CHANGES IN THE FORECAST CLOSELY. A GALE
WATCH IS NOW IN EFFECT MONDAY AND MONDAY NIGHT FOR ALL MARINE AREAS.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR
     LHZ361>363-421-422-441>443-462>464.

LAKE ST CLAIR...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LEZ444.

&&

$$

AVIATION.....KURIMSKI
SHORT TERM...BT
LONG TERM....HLO/MM
MARINE.......HLO


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 222341
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
641 PM EST SAT NOV 22 2014


.AVIATION...

//DISCUSSION...

LOW PRESSURE ORGANIZING OVER SOUTHERN CANADA AND THE PLAINS STATES
TONIGHT WILL MAINTAIN MILDER SOUTHERLY WIND OVER SE MICHIGAN THROUGH
SUNDAY. LOW LEVEL WIND SHEAR REMAINS IN PLACE TONIGHT BELOW 2000
FEET IN THIS PATTERN ENHANCED BY LIMITED BOUNDARY LAYER MIXING.
CEILINGS WILL BE NO BETTER THAN MVFR THROUGH THE PERIOD COMBINED
WITH INTERVALS OF IFR IN BOTH CEILING AND VISIBILITY DEPENDING ON
MILD AIR INTERACTIONS WITH SNOW COVER. WITH SNOW COVER BASICALLY
GONE AT THE METRO AIRPORTS CONDITIONS HAVE IMPROVED VASTLY. THE
LATEST OBSERVATIONAL DATA SUGGESTS THE NEXT SIGNIFICANT DROP IN
CONDITIONS IS MOST LIKELY SUNDAY MORNING AS INCREASING SURFACE
DEWPOINT COMBINES WITH THE NEXT SURGE OF RAIN SHOWERS. EXPECT THE
SHOWERS TO LAST OFF AND ON INTO SUNDAY AFTERNOON WITH A MODEST
IMPROVEMENT TO LOW END MVFR CEILING DURING THE DAY.

FOR DTW... PRECIPITATION TYPE WILL REMAIN FIRMLY IN THE FORM OF ALL
RAIN GOING FORWARD IN THE FORECAST THROUGH SUNDAY. TEMPERATURES WILL
CONTINUE A STEADY RISE EVEN AFTER SUNSET TONIGHT WITH READINGS IN
THE LOWER TO MID 40S BEFORE THE NEXT SURGE OF RAIN SHOWERS BEGINS
SUNDAY MORNING.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE TODAY THROUGH
  SUNDAY.

&&

.PREV DISCUSSION...ISSUED 420 PM EST SAT NOV 22 2014

SHORT TERM... LATE AFTERNOON THROUGH TONIGHT

LOW PRESSURE DEVELOPING IN CENTRAL CANADA INTO THE NORTHERN PLAINS
STATES WILL MAINTAIN SOUTHERLY WIND AND A SUPPLY OF MILD AIR INTO SE
MICHIGAN THROUGH TONIGHT. AFTER A SLIGHT EARLY EVENING DROP BACK
TOWARD THE UPPER 30S...TEMPERATURES WILL EASILY BE ABLE TO REMAIN
STEADY OR SLOWLY RISE THROUGH THE LOWER AND MID 40S DURING THE
NIGHT. THIS MILD AIR IS ALSO MOISTURE LADEN WHICH WILL KEEP CLUSTERS
OF SHOWERS GOING AMID CLOUDY SKY WITH FOG AND DRIZZLE THROUGH THE
REGION.

MID AFTERNOON OBSERVATIONAL TRENDS FAVOR THE GREATEST COVERAGE OF
SHOWERS DURING LATE AFTERNOON THROUGH MID EVENING FOLLOWED BY A
BREAK DURING THE OVERNIGHT HOURS. SATELLITE AND MODEL ANALYSIS
FIELDS POINT TO ANOTHER WEAK WAVE ALOFT HELPING TO SUPPORT CLUSTERS
OF SHOWERS MOVING IN FROM NORTHERN INDIANA AND SW LOWER MICHIGAN.
THE SHORT WAVE FORCING WILL INTERACT WITH THE LOW LEVEL THETA-E
RIDGE BEING DRAWN INTO SE MICHIGAN AROUND THE 850 MB LEVEL. THE
ASSOCIATED MOISTURE TRANSPORT AND ELEVATED INSTABILITY IS MODEST
WHICH WILL LIMIT SHOWER INTENSITY...AND THE WAVE IS PROGRESSIVE
ENOUGH TO SLIDE THROUGH OUR AREA BY MIDNIGHT. THE PASSAGE OF THIS
FEATURE WILL THEN LIMIT PRECIPITATION TO PATCHY DRIZZLE WITHIN AREAS
OF FOG LIKELY TO FORM AS INCREASINGLY MILD AIR FLOWS OVER SNOW
COVERED GROUND. PLAN TO MONITOR OBSERVATIONAL TRENDS FOR DENSE FOG
POTENTIAL WHICH SHOULD BE LIMITED TO THE LAKE EFFECT ENHANCED M-59/I-
69 CORRIDOR AND POSSIBLY POINTS NORTH. SNOW COVER IS REPORTED TO BE
DIMINISHING RAPIDLY TO THE SOUTH THROUGH THE DETROIT METRO AREA
TOWARD THE OHIO BORDER.

LONG TERM...SUNDAY THROUGH NEXT SATURDAY

WARM AND RAINY PATTERN WILL CONTINUE SUNDAY AND EARLY MONDAY BEFORE
A COLD FRONT USHERS IN STRONG WINDS AND COLDER AIR LATER IN THE DAY.

LARGE UPPER TROUGH OVER THE PACIFIC NORTHWEST AND NORTHERN ROCKIES
WILL PROGRESS EAST TOWARDS THE GREAT LAKES...SCOOPING UP THE UPPER
LOW NOW SEEN ON WATER VAPOR OVER TEXAS IN THE PROCESS. THE REMNANTS
OF THE TEXAS WAVE LOOK TO LIFT NORTHWARD ACROSS LOWER MICHIGAN
SUNDAY NIGHT...WITH THE UPPER TROUGH AXIS FOLLOWING BY MONDAY NIGHT.
MODELS CONTINUE TO KEY IN ON A BAND OF ISENTROPIC LIFT PROGRESSING
NORTHWARD OVER SOUTHEAST MICHIGAN...WITH TIMING NOW RANGING FROM
MORNING TO AFTERNOON. THIS BAND OF ASCENT COMBINED WITH AMPLE
MOISTURE REMAINING OVER THE AREA SHOULD PROVIDE A GOOD COVERAGE OF
RAIN SHOWERS TOMORROW. OTHER CONCERN WILL BE CONTINUED WARM AIR
ADVECTION OVER THE COLD GROUND WHERE AT LEAST SOME SNOW COVER WILL
REMAIN. THIS COULD LEAD TO SOME FOG FORMATION...BUT THICKNESS MAY BE
ENOUGH TO HAVE AN IMPACT TO INTERESTS OTHER THAN AVIATION. BETTER
INFLUX OF MOISTURE AND ADDITIONAL WARM AIR LOOKS TO OCCUR LATER IN
THE DAY AND OVERNIGHT AS THE UPPER WAVE FROM TEXAS APPROACHES AND
THE LOW-LEVEL JET RAMPS UP OVER THE OHIO VALLEY AHEAD OF THE
ADVANCING UPPER TROUGH. PVA AHEAD OF THE APPROACHING WAVE COMBINED
WITH ASCENT ALONG THE WARM FRONT AND A COUPLED JET STRUCTURE SHOULD
PROVIDE DEEP LAYER FORCING. THIS WILL COMBINE WITH PW VALUES IN
EXCESS OF 1.0 INCHES TO PROVIDE A WIDESPREAD RAIN EVENT DURING THE
EVENING AND OVERNIGHT. QPF AMOUNTS LOOK TO RANGE BETWEEN 0.6 AND 1.0
INCH. FLOODING DOES NOT LOOK TO BE A CONCERN GIVEN LOW CURRENT LOW
RIVER LEVELS AND ONLY A SMALL AMOUNT OF SNOW COVER REMAINING.
TEMPERATURES WILL REMAIN VERY MILD...SUPPORTED BY H850 TEMPS
REACHING AROUND 8C IN THE WARM SECTOR. THIS SHOULD SUPPORT MAX TEMPS
IN THE UPPER 40S TO LOW 50S TOMORROW...WITH ONLY A SMALL DROP INTO
THE MID 40S FOR SUNDAY NIGHT.

MODELS SOLUTIONS CONTINUE TO DIVERGE WITH THE TRACK AND STRENGTH OF
THE SURFACE LOW AS IT LIFTS ACROSS WESTERN AND NORTHERN LOWER
MICHIGAN SUNDAY NIGHT INTO MONDAY. BIGGEST IMPLICATION WITH THIS IS
THE AFFECT ON AND UNCERTAINTY WITH THE WIND SPEED FORECAST. CURRENT
PREFERENCE GOES TO THE LAST FEW EURO/GEM SOLUTIONS DUE TO GOOD RUN
TO RUN CONSISTENCY AND GOOD OVERALL CONSENSUS WITHIN THE MODEL
GUIDANCE ENVELOPE. THIS HAS AN AVERAGE LOW PRESSURE OF 974MB. 12Z
NAM WAS NOT TOO FAR OFF THIS AND SHOWS GOOD DESCENT BEHIND THE COLD
FRONT ALONG ISENTROPIC SURFACES BETWEEN 280-290K (INTO THE GROUND).
THIS DESCENT COMBINED WITH STEEPENING LAPSE RATES/DEEPENING BOUNDARY
LAYER FROM STRONG COLD AIR ADVECTION...A TIGHT SURFACE PRESSURE
GRADIENT...AND A CORE OF 40-55 KNOT WINDS BETWEEN 900-800MB MAY
ALLOW VERY STRONG WIND GUSTS TO REACH THE SURFACE. CURRENT FORECAST
HIGHLIGHTS GUSTS 40 TO 45 MPH...WITH POTENTIAL TO REACH 50 MPH.
HEADLINES ARE A POSSIBILITY...BUT THERE IS STILL PLENTY OF TIME FOR
THINGS TO CHANGE. A FEW RUMBLES OF THUNDER MAY ALSO BE POSSIBLE
EARLY ON MONDAY IN THE WARM SECTOR AS INSTABILITY INCREASES...AND
POSSIBLY BECOMES SURFACE BASED. RAIN WILL CHANGE TO SNOW BEHIND THE
FRONT AS TEMPERATURES FALL DURING THE LATE AFTERNOON AND
EVENING...WITH LIGHT ACCUMULATIONS POSSIBLE IN THE EVENING AND THEN
OVERNIGHT AS LAKE EFFECT PROCESSES RAMP UP. DRIER AIR WILL FILTER
INTO THE REGION...POTENTIALLY CLEARING MOISTURE OUT OF THE DGZ IN
THE EVENING PER 12Z NAM. GEM/EURO TRY TO BRUSH THE NORTHWEST CORNER
OF THE FORECAST AREA WITH DEFORMATION LINGERING BEHIND THE DEPARTING
SYSTEM...SOMETHING TO KEEP AN EYE ON FOR THE SAGINAW VALLEY BUT
ACCUMULATIONS LOOK LIGHT AT THIS TIME.

LOW PRESSURE TRACKING NORTHEAST OF THE REGION WILL CONTINUE TO BRING
A LOW CHANCE FOR SNOW SHOWERS TO MICHIGAN ON TUESDAY. BREEZY
CONDITIONS WILL CONTINUE THROUGH THE DAY WITH GUSTS STILL IN THE 20
TO 30 MPH RANGE. HIGH PRESSURE CREEPING IN FROM THE SOUTHWEST WILL
BRING DRY CONDITIONS TO THE AREA...BUT ARCTIC AIR INTRUSION COMES
BACK IN PLACE WITH TEMPS 10 TO 15 DEGREES BELOW NORMAL. A CLIPPER
SYSTEM COULD BRING ACCUMULATING SNOW ON THANKSGIVING...MORE DETAILS
WHEN NWP COMES CLOSER TO A CONSENSUS.

MARINE...

SOUTHWEST WINDS WILL CONTINUE TO DECREASE THROUGH THE EARLY EVENING
ACROSS THE CENTRAL GREAT LAKES...ALLOWING WINDS WAVES OVER LAKE
HURON TO GRADUALLY SUBSIDE. WINDS WILL SHIFT MORE SOUTHERLY SUNDAY
AND SUNDAY NIGHT AS A LARGE LOW PRESSURE SYSTEM BEGINS TO LIFT
TOWARDS THE AREA FROM THE PLAINS. WARMER AIR WILL ALSO CONTINUE TO
SURGE INTO THE AREA...PROVIDING A FAIRLY STABLE ENVIRONMENT OVER THE
WARM LAKE WATERS. THIS SHOULD HELP LIMIT GUSTS TO THE 15 TO 25 KNOT
RANGE SUNDAY AND SUNDAY NIGHT.

THE LOW PRESSURE SYSTEM WILL LIFT ACROSS THE WESTERN AND NORTHERN
GREAT LAKES SUNDAY NIGHT THROUGH MONDAY...SENDING A STRONG COLD
FRONT ACROSS THE AREA MONDAY AFTERNOON. GALE FORCE WINDS LOOK LIKELY
BEHIND THE COLD FRONT MONDAY AND MONDAY NIGHT AS A TIGHT PRESSURE
GRADIENT DEVELOPS AND MUCH COLDER AIR RUSHES INTO THE AREA...WITH
POTENTIAL FOR WIND GUSTS TO EXCEED 45 KNOTS. THERE IS STILL SOME
UNCERTAINTY WITH HOW MUCH THIS SYSTEM WILL DEEPEN AND THE EXACT
TRACK IT WILL TAKE ACROSS THE GREAT LAKES. FURTHER ADJUSTMENT TO THE
FORECAST IS POSSIBLE. IF THE SYSTEM DEEPENS FURTHER THAN CURRENTLY
ANTICIPATED...STORM FORCE WIND GUSTS COULD DEVELOP OVER PORTIONS OF
LAKE HURON. THOSE WITH INTERESTS IN THE GREAT LAKES MONDAY AND
MONDAY NIGHT SHOULD FOLLOW CHANGES IN THE FORECAST CLOSELY. A GALE
WATCH IS NOW IN EFFECT MONDAY AND MONDAY NIGHT FOR ALL MARINE AREAS.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR
     LHZ361>363-421-422-441>443-462>464.

LAKE ST CLAIR...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LEZ444.

&&

$$

AVIATION.....KURIMSKI
SHORT TERM...BT
LONG TERM....HLO/MM
MARINE.......HLO


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 222341
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
641 PM EST SAT NOV 22 2014


.AVIATION...

//DISCUSSION...

LOW PRESSURE ORGANIZING OVER SOUTHERN CANADA AND THE PLAINS STATES
TONIGHT WILL MAINTAIN MILDER SOUTHERLY WIND OVER SE MICHIGAN THROUGH
SUNDAY. LOW LEVEL WIND SHEAR REMAINS IN PLACE TONIGHT BELOW 2000
FEET IN THIS PATTERN ENHANCED BY LIMITED BOUNDARY LAYER MIXING.
CEILINGS WILL BE NO BETTER THAN MVFR THROUGH THE PERIOD COMBINED
WITH INTERVALS OF IFR IN BOTH CEILING AND VISIBILITY DEPENDING ON
MILD AIR INTERACTIONS WITH SNOW COVER. WITH SNOW COVER BASICALLY
GONE AT THE METRO AIRPORTS CONDITIONS HAVE IMPROVED VASTLY. THE
LATEST OBSERVATIONAL DATA SUGGESTS THE NEXT SIGNIFICANT DROP IN
CONDITIONS IS MOST LIKELY SUNDAY MORNING AS INCREASING SURFACE
DEWPOINT COMBINES WITH THE NEXT SURGE OF RAIN SHOWERS. EXPECT THE
SHOWERS TO LAST OFF AND ON INTO SUNDAY AFTERNOON WITH A MODEST
IMPROVEMENT TO LOW END MVFR CEILING DURING THE DAY.

FOR DTW... PRECIPITATION TYPE WILL REMAIN FIRMLY IN THE FORM OF ALL
RAIN GOING FORWARD IN THE FORECAST THROUGH SUNDAY. TEMPERATURES WILL
CONTINUE A STEADY RISE EVEN AFTER SUNSET TONIGHT WITH READINGS IN
THE LOWER TO MID 40S BEFORE THE NEXT SURGE OF RAIN SHOWERS BEGINS
SUNDAY MORNING.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE TODAY THROUGH
  SUNDAY.

&&

.PREV DISCUSSION...ISSUED 420 PM EST SAT NOV 22 2014

SHORT TERM... LATE AFTERNOON THROUGH TONIGHT

LOW PRESSURE DEVELOPING IN CENTRAL CANADA INTO THE NORTHERN PLAINS
STATES WILL MAINTAIN SOUTHERLY WIND AND A SUPPLY OF MILD AIR INTO SE
MICHIGAN THROUGH TONIGHT. AFTER A SLIGHT EARLY EVENING DROP BACK
TOWARD THE UPPER 30S...TEMPERATURES WILL EASILY BE ABLE TO REMAIN
STEADY OR SLOWLY RISE THROUGH THE LOWER AND MID 40S DURING THE
NIGHT. THIS MILD AIR IS ALSO MOISTURE LADEN WHICH WILL KEEP CLUSTERS
OF SHOWERS GOING AMID CLOUDY SKY WITH FOG AND DRIZZLE THROUGH THE
REGION.

MID AFTERNOON OBSERVATIONAL TRENDS FAVOR THE GREATEST COVERAGE OF
SHOWERS DURING LATE AFTERNOON THROUGH MID EVENING FOLLOWED BY A
BREAK DURING THE OVERNIGHT HOURS. SATELLITE AND MODEL ANALYSIS
FIELDS POINT TO ANOTHER WEAK WAVE ALOFT HELPING TO SUPPORT CLUSTERS
OF SHOWERS MOVING IN FROM NORTHERN INDIANA AND SW LOWER MICHIGAN.
THE SHORT WAVE FORCING WILL INTERACT WITH THE LOW LEVEL THETA-E
RIDGE BEING DRAWN INTO SE MICHIGAN AROUND THE 850 MB LEVEL. THE
ASSOCIATED MOISTURE TRANSPORT AND ELEVATED INSTABILITY IS MODEST
WHICH WILL LIMIT SHOWER INTENSITY...AND THE WAVE IS PROGRESSIVE
ENOUGH TO SLIDE THROUGH OUR AREA BY MIDNIGHT. THE PASSAGE OF THIS
FEATURE WILL THEN LIMIT PRECIPITATION TO PATCHY DRIZZLE WITHIN AREAS
OF FOG LIKELY TO FORM AS INCREASINGLY MILD AIR FLOWS OVER SNOW
COVERED GROUND. PLAN TO MONITOR OBSERVATIONAL TRENDS FOR DENSE FOG
POTENTIAL WHICH SHOULD BE LIMITED TO THE LAKE EFFECT ENHANCED M-59/I-
69 CORRIDOR AND POSSIBLY POINTS NORTH. SNOW COVER IS REPORTED TO BE
DIMINISHING RAPIDLY TO THE SOUTH THROUGH THE DETROIT METRO AREA
TOWARD THE OHIO BORDER.

LONG TERM...SUNDAY THROUGH NEXT SATURDAY

WARM AND RAINY PATTERN WILL CONTINUE SUNDAY AND EARLY MONDAY BEFORE
A COLD FRONT USHERS IN STRONG WINDS AND COLDER AIR LATER IN THE DAY.

LARGE UPPER TROUGH OVER THE PACIFIC NORTHWEST AND NORTHERN ROCKIES
WILL PROGRESS EAST TOWARDS THE GREAT LAKES...SCOOPING UP THE UPPER
LOW NOW SEEN ON WATER VAPOR OVER TEXAS IN THE PROCESS. THE REMNANTS
OF THE TEXAS WAVE LOOK TO LIFT NORTHWARD ACROSS LOWER MICHIGAN
SUNDAY NIGHT...WITH THE UPPER TROUGH AXIS FOLLOWING BY MONDAY NIGHT.
MODELS CONTINUE TO KEY IN ON A BAND OF ISENTROPIC LIFT PROGRESSING
NORTHWARD OVER SOUTHEAST MICHIGAN...WITH TIMING NOW RANGING FROM
MORNING TO AFTERNOON. THIS BAND OF ASCENT COMBINED WITH AMPLE
MOISTURE REMAINING OVER THE AREA SHOULD PROVIDE A GOOD COVERAGE OF
RAIN SHOWERS TOMORROW. OTHER CONCERN WILL BE CONTINUED WARM AIR
ADVECTION OVER THE COLD GROUND WHERE AT LEAST SOME SNOW COVER WILL
REMAIN. THIS COULD LEAD TO SOME FOG FORMATION...BUT THICKNESS MAY BE
ENOUGH TO HAVE AN IMPACT TO INTERESTS OTHER THAN AVIATION. BETTER
INFLUX OF MOISTURE AND ADDITIONAL WARM AIR LOOKS TO OCCUR LATER IN
THE DAY AND OVERNIGHT AS THE UPPER WAVE FROM TEXAS APPROACHES AND
THE LOW-LEVEL JET RAMPS UP OVER THE OHIO VALLEY AHEAD OF THE
ADVANCING UPPER TROUGH. PVA AHEAD OF THE APPROACHING WAVE COMBINED
WITH ASCENT ALONG THE WARM FRONT AND A COUPLED JET STRUCTURE SHOULD
PROVIDE DEEP LAYER FORCING. THIS WILL COMBINE WITH PW VALUES IN
EXCESS OF 1.0 INCHES TO PROVIDE A WIDESPREAD RAIN EVENT DURING THE
EVENING AND OVERNIGHT. QPF AMOUNTS LOOK TO RANGE BETWEEN 0.6 AND 1.0
INCH. FLOODING DOES NOT LOOK TO BE A CONCERN GIVEN LOW CURRENT LOW
RIVER LEVELS AND ONLY A SMALL AMOUNT OF SNOW COVER REMAINING.
TEMPERATURES WILL REMAIN VERY MILD...SUPPORTED BY H850 TEMPS
REACHING AROUND 8C IN THE WARM SECTOR. THIS SHOULD SUPPORT MAX TEMPS
IN THE UPPER 40S TO LOW 50S TOMORROW...WITH ONLY A SMALL DROP INTO
THE MID 40S FOR SUNDAY NIGHT.

MODELS SOLUTIONS CONTINUE TO DIVERGE WITH THE TRACK AND STRENGTH OF
THE SURFACE LOW AS IT LIFTS ACROSS WESTERN AND NORTHERN LOWER
MICHIGAN SUNDAY NIGHT INTO MONDAY. BIGGEST IMPLICATION WITH THIS IS
THE AFFECT ON AND UNCERTAINTY WITH THE WIND SPEED FORECAST. CURRENT
PREFERENCE GOES TO THE LAST FEW EURO/GEM SOLUTIONS DUE TO GOOD RUN
TO RUN CONSISTENCY AND GOOD OVERALL CONSENSUS WITHIN THE MODEL
GUIDANCE ENVELOPE. THIS HAS AN AVERAGE LOW PRESSURE OF 974MB. 12Z
NAM WAS NOT TOO FAR OFF THIS AND SHOWS GOOD DESCENT BEHIND THE COLD
FRONT ALONG ISENTROPIC SURFACES BETWEEN 280-290K (INTO THE GROUND).
THIS DESCENT COMBINED WITH STEEPENING LAPSE RATES/DEEPENING BOUNDARY
LAYER FROM STRONG COLD AIR ADVECTION...A TIGHT SURFACE PRESSURE
GRADIENT...AND A CORE OF 40-55 KNOT WINDS BETWEEN 900-800MB MAY
ALLOW VERY STRONG WIND GUSTS TO REACH THE SURFACE. CURRENT FORECAST
HIGHLIGHTS GUSTS 40 TO 45 MPH...WITH POTENTIAL TO REACH 50 MPH.
HEADLINES ARE A POSSIBILITY...BUT THERE IS STILL PLENTY OF TIME FOR
THINGS TO CHANGE. A FEW RUMBLES OF THUNDER MAY ALSO BE POSSIBLE
EARLY ON MONDAY IN THE WARM SECTOR AS INSTABILITY INCREASES...AND
POSSIBLY BECOMES SURFACE BASED. RAIN WILL CHANGE TO SNOW BEHIND THE
FRONT AS TEMPERATURES FALL DURING THE LATE AFTERNOON AND
EVENING...WITH LIGHT ACCUMULATIONS POSSIBLE IN THE EVENING AND THEN
OVERNIGHT AS LAKE EFFECT PROCESSES RAMP UP. DRIER AIR WILL FILTER
INTO THE REGION...POTENTIALLY CLEARING MOISTURE OUT OF THE DGZ IN
THE EVENING PER 12Z NAM. GEM/EURO TRY TO BRUSH THE NORTHWEST CORNER
OF THE FORECAST AREA WITH DEFORMATION LINGERING BEHIND THE DEPARTING
SYSTEM...SOMETHING TO KEEP AN EYE ON FOR THE SAGINAW VALLEY BUT
ACCUMULATIONS LOOK LIGHT AT THIS TIME.

LOW PRESSURE TRACKING NORTHEAST OF THE REGION WILL CONTINUE TO BRING
A LOW CHANCE FOR SNOW SHOWERS TO MICHIGAN ON TUESDAY. BREEZY
CONDITIONS WILL CONTINUE THROUGH THE DAY WITH GUSTS STILL IN THE 20
TO 30 MPH RANGE. HIGH PRESSURE CREEPING IN FROM THE SOUTHWEST WILL
BRING DRY CONDITIONS TO THE AREA...BUT ARCTIC AIR INTRUSION COMES
BACK IN PLACE WITH TEMPS 10 TO 15 DEGREES BELOW NORMAL. A CLIPPER
SYSTEM COULD BRING ACCUMULATING SNOW ON THANKSGIVING...MORE DETAILS
WHEN NWP COMES CLOSER TO A CONSENSUS.

MARINE...

SOUTHWEST WINDS WILL CONTINUE TO DECREASE THROUGH THE EARLY EVENING
ACROSS THE CENTRAL GREAT LAKES...ALLOWING WINDS WAVES OVER LAKE
HURON TO GRADUALLY SUBSIDE. WINDS WILL SHIFT MORE SOUTHERLY SUNDAY
AND SUNDAY NIGHT AS A LARGE LOW PRESSURE SYSTEM BEGINS TO LIFT
TOWARDS THE AREA FROM THE PLAINS. WARMER AIR WILL ALSO CONTINUE TO
SURGE INTO THE AREA...PROVIDING A FAIRLY STABLE ENVIRONMENT OVER THE
WARM LAKE WATERS. THIS SHOULD HELP LIMIT GUSTS TO THE 15 TO 25 KNOT
RANGE SUNDAY AND SUNDAY NIGHT.

THE LOW PRESSURE SYSTEM WILL LIFT ACROSS THE WESTERN AND NORTHERN
GREAT LAKES SUNDAY NIGHT THROUGH MONDAY...SENDING A STRONG COLD
FRONT ACROSS THE AREA MONDAY AFTERNOON. GALE FORCE WINDS LOOK LIKELY
BEHIND THE COLD FRONT MONDAY AND MONDAY NIGHT AS A TIGHT PRESSURE
GRADIENT DEVELOPS AND MUCH COLDER AIR RUSHES INTO THE AREA...WITH
POTENTIAL FOR WIND GUSTS TO EXCEED 45 KNOTS. THERE IS STILL SOME
UNCERTAINTY WITH HOW MUCH THIS SYSTEM WILL DEEPEN AND THE EXACT
TRACK IT WILL TAKE ACROSS THE GREAT LAKES. FURTHER ADJUSTMENT TO THE
FORECAST IS POSSIBLE. IF THE SYSTEM DEEPENS FURTHER THAN CURRENTLY
ANTICIPATED...STORM FORCE WIND GUSTS COULD DEVELOP OVER PORTIONS OF
LAKE HURON. THOSE WITH INTERESTS IN THE GREAT LAKES MONDAY AND
MONDAY NIGHT SHOULD FOLLOW CHANGES IN THE FORECAST CLOSELY. A GALE
WATCH IS NOW IN EFFECT MONDAY AND MONDAY NIGHT FOR ALL MARINE AREAS.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR
     LHZ361>363-421-422-441>443-462>464.

LAKE ST CLAIR...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LEZ444.

&&

$$

AVIATION.....KURIMSKI
SHORT TERM...BT
LONG TERM....HLO/MM
MARINE.......HLO


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 222120
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
420 PM EST SAT NOV 22 2014

.SHORT TERM... LATE AFTERNOON THROUGH TONIGHT

LOW PRESSURE DEVELOPING IN CENTRAL CANADA INTO THE NORTHERN PLAINS
STATES WILL MAINTAIN SOUTHERLY WIND AND A SUPPLY OF MILD AIR INTO SE
MICHIGAN THROUGH TONIGHT. AFTER A SLIGHT EARLY EVENING DROP BACK
TOWARD THE UPPER 30S...TEMPERATURES WILL EASILY BE ABLE TO REMAIN
STEADY OR SLOWLY RISE THROUGH THE LOWER AND MID 40S DURING THE
NIGHT. THIS MILD AIR IS ALSO MOISTURE LADEN WHICH WILL KEEP CLUSTERS
OF SHOWERS GOING AMID CLOUDY SKY WITH FOG AND DRIZZLE THROUGH THE
REGION.

MID AFTERNOON OBSERVATIONAL TRENDS FAVOR THE GREATEST COVERAGE OF
SHOWERS DURING LATE AFTERNOON THROUGH MID EVENING FOLLOWED BY A
BREAK DURING THE OVERNIGHT HOURS. SATELLITE AND MODEL ANALYSIS
FIELDS POINT TO ANOTHER WEAK WAVE ALOFT HELPING TO SUPPORT CLUSTERS
OF SHOWERS MOVING IN FROM NORTHERN INDIANA AND SW LOWER MICHIGAN.
THE SHORT WAVE FORCING WILL INTERACT WITH THE LOW LEVEL THETA-E
RIDGE BEING DRAWN INTO SE MICHIGAN AROUND THE 850 MB LEVEL. THE
ASSOCIATED MOISTURE TRANSPORT AND ELEVATED INSTABILITY IS MODEST
WHICH WILL LIMIT SHOWER INTENSITY...AND THE WAVE IS PROGRESSIVE
ENOUGH TO SLIDE THROUGH OUR AREA BY MIDNIGHT. THE PASSAGE OF THIS
FEATURE WILL THEN LIMIT PRECIPITATION TO PATCHY DRIZZLE WITHIN AREAS
OF FOG LIKELY TO FORM AS INCREASINGLY MILD AIR FLOWS OVER SNOW
COVERED GROUND. PLAN TO MONITOR OBSERVATIONAL TRENDS FOR DENSE FOG
POTENTIAL WHICH SHOULD BE LIMITED TO THE LAKE EFFECT ENHANCED M-59/I-
69 CORRIDOR AND POSSIBLY POINTS NORTH. SNOW COVER IS REPORTED TO BE
DIMINISHING RAPIDLY TO THE SOUTH THROUGH THE DETROIT METRO AREA
TOWARD THE OHIO BORDER.

&&

.LONG TERM...SUNDAY THROUGH NEXT SATURDAY

WARM AND RAINY PATTERN WILL CONTINUE SUNDAY AND EARLY MONDAY BEFORE
A COLD FRONT USHERS IN STRONG WINDS AND COLDER AIR LATER IN THE DAY.

LARGE UPPER TROUGH OVER THE PACIFIC NORTHWEST AND NORTHERN ROCKIES
WILL PROGRESS EAST TOWARDS THE GREAT LAKES...SCOOPING UP THE UPPER
LOW NOW SEEN ON WATER VAPOR OVER TEXAS IN THE PROCESS. THE REMNANTS
OF THE TEXAS WAVE LOOK TO LIFT NORTHWARD ACROSS LOWER MICHIGAN
SUNDAY NIGHT...WITH THE UPPER TROUGH AXIS FOLLOWING BY MONDAY NIGHT.
MODELS CONTINUE TO KEY IN ON A BAND OF ISENTROPIC LIFT PROGRESSING
NORTHWARD OVER SOUTHEAST MICHIGAN...WITH TIMING NOW RANGING FROM
MORNING TO AFTERNOON. THIS BAND OF ASCENT COMBINED WITH AMPLE
MOISTURE REMAINING OVER THE AREA SHOULD PROVIDE A GOOD COVERAGE OF
RAIN SHOWERS TOMORROW. OTHER CONCERN WILL BE CONTINUED WARM AIR
ADVECTION OVER THE COLD GROUND WHERE AT LEAST SOME SNOW COVER WILL
REMAIN. THIS COULD LEAD TO SOME FOG FORMATION...BUT THICKNESS MAY BE
ENOUGH TO HAVE AN IMPACT TO INTERESTS OTHER THAN AVIATION. BETTER
INFLUX OF MOISTURE AND ADDITIONAL WARM AIR LOOKS TO OCCUR LATER IN
THE DAY AND OVERNIGHT AS THE UPPER WAVE FROM TEXAS APPROACHES AND
THE LOW-LEVEL JET RAMPS UP OVER THE OHIO VALLEY AHEAD OF THE
ADVANCING UPPER TROUGH. PVA AHEAD OF THE APPROACHING WAVE COMBINED
WITH ASCENT ALONG THE WARM FRONT AND A COUPLED JET STRUCTURE SHOULD
PROVIDE DEEP LAYER FORCING. THIS WILL COMBINE WITH PW VALUES IN
EXCESS OF 1.0 INCHES TO PROVIDE A WIDESPREAD RAIN EVENT DURING THE
EVENING AND OVERNIGHT. QPF AMOUNTS LOOK TO RANGE BETWEEN 0.6 AND 1.0
INCH. FLOODING DOES NOT LOOK TO BE A CONCERN GIVEN LOW CURRENT LOW
RIVER LEVELS AND ONLY A SMALL AMOUNT OF SNOW COVER REMAINING.
TEMPERATURES WILL REMAIN VERY MILD...SUPPORTED BY H850 TEMPS
REACHING AROUND 8C IN THE WARM SECTOR. THIS SHOULD SUPPORT MAX TEMPS
IN THE UPPER 40S TO LOW 50S TOMORROW...WITH ONLY A SMALL DROP INTO
THE MID 40S FOR SUNDAY NIGHT.

MODELS SOLUTIONS CONTINUE TO DIVERGE WITH THE TRACK AND STRENGTH OF
THE SURFACE LOW AS IT LIFTS ACROSS WESTERN AND NORTHERN LOWER
MICHIGAN SUNDAY NIGHT INTO MONDAY. BIGGEST IMPLICATION WITH THIS IS
THE AFFECT ON AND UNCERTAINTY WITH THE WIND SPEED FORECAST. CURRENT
PREFERENCE GOES TO THE LAST FEW EURO/GEM SOLUTIONS DUE TO GOOD RUN
TO RUN CONSISTENCY AND GOOD OVERALL CONSENSUS WITHIN THE MODEL
GUIDANCE ENVELOPE. THIS HAS AN AVERAGE LOW PRESSURE OF 974MB. 12Z
NAM WAS NOT TOO FAR OFF THIS AND SHOWS GOOD DESCENT BEHIND THE COLD
FRONT ALONG ISENTROPIC SURFACES BETWEEN 280-290K (INTO THE GROUND).
THIS DESCENT COMBINED WITH STEEPENING LAPSE RATES/DEEPENING BOUNDARY
LAYER FROM STRONG COLD AIR ADVECTION...A TIGHT SURFACE PRESSURE
GRADIENT...AND A CORE OF 40-55 KNOT WINDS BETWEEN 900-800MB MAY
ALLOW VERY STRONG WIND GUSTS TO REACH THE SURFACE. CURRENT FORECAST
HIGHLIGHTS GUSTS 40 TO 45 MPH...WITH POTENTIAL TO REACH 50 MPH.
HEADLINES ARE A POSSIBILITY...BUT THERE IS STILL PLENTY OF TIME FOR
THINGS TO CHANGE. A FEW RUMBLES OF THUNDER MAY ALSO BE POSSIBLE
EARLY ON MONDAY IN THE WARM SECTOR AS INSTABILITY INCREASES...AND
POSSIBLY BECOMES SURFACE BASED. RAIN WILL CHANGE TO SNOW BEHIND THE
FRONT AS TEMPERATURES FALL DURING THE LATE AFTERNOON AND
EVENING...WITH LIGHT ACCUMULATIONS POSSIBLE IN THE EVENING AND THEN
OVERNIGHT AS LAKE EFFECT PROCESSES RAMP UP. DRIER AIR WILL FILTER
INTO THE REGION...POTENTIALLY CLEARING MOISTURE OUT OF THE DGZ IN
THE EVENING PER 12Z NAM. GEM/EURO TRY TO BRUSH THE NORTHWEST CORNER
OF THE FORECAST AREA WITH DEFORMATION LINGERING BEHIND THE DEPARTING
SYSTEM...SOMETHING TO KEEP AN EYE ON FOR THE SAGINAW VALLEY BUT
ACCUMULATIONS LOOK LIGHT AT THIS TIME.

LOW PRESSURE TRACKING NORTHEAST OF THE REGION WILL CONTINUE TO BRING
A LOW CHANCE FOR SNOW SHOWERS TO MICHIGAN ON TUESDAY. BREEZY
CONDITIONS WILL CONTINUE THROUGH THE DAY WITH GUSTS STILL IN THE 20
TO 30 MPH RANGE. HIGH PRESSURE CREEPING IN FROM THE SOUTHWEST WILL
BRING DRY CONDITIONS TO THE AREA...BUT ARCTIC AIR INTRUSION COMES
BACK IN PLACE WITH TEMPS 10 TO 15 DEGREES BELOW NORMAL. A CLIPPER
SYSTEM COULD BRING ACCUMULATING SNOW ON THANKSGIVING...MORE DETAILS
WHEN NWP COMES CLOSER TO A CONSENSUS.

&&

.MARINE...

SOUTHWEST WINDS WILL CONTINUE TO DECREASE THROUGH THE EARLY EVENING
ACROSS THE CENTRAL GREAT LAKES...ALLOWING WINDS WAVES OVER LAKE
HURON TO GRADUALLY SUBSIDE. WINDS WILL SHIFT MORE SOUTHERLY SUNDAY
AND SUNDAY NIGHT AS A LARGE LOW PRESSURE SYSTEM BEGINS TO LIFT
TOWARDS THE AREA FROM THE PLAINS. WARMER AIR WILL ALSO CONTINUE TO
SURGE INTO THE AREA...PROVIDING A FAIRLY STABLE ENVIRONMENT OVER THE
WARM LAKE WATERS. THIS SHOULD HELP LIMIT GUSTS TO THE 15 TO 25 KNOT
RANGE SUNDAY AND SUNDAY NIGHT.

THE LOW PRESSURE SYSTEM WILL LIFT ACROSS THE WESTERN AND NORTHERN
GREAT LAKES SUNDAY NIGHT THROUGH MONDAY...SENDING A STRONG COLD
FRONT ACROSS THE AREA MONDAY AFTERNOON. GALE FORCE WINDS LOOK LIKELY
BEHIND THE COLD FRONT MONDAY AND MONDAY NIGHT AS A TIGHT PRESSURE
GRADIENT DEVELOPS AND MUCH COLDER AIR RUSHES INTO THE AREA...WITH
POTENTIAL FOR WIND GUSTS TO EXCEED 45 KNOTS. THERE IS STILL SOME
UNCERTAINTY WITH HOW MUCH THIS SYSTEM WILL DEEPEN AND THE EXACT
TRACK IT WILL TAKE ACROSS THE GREAT LAKES. FURTHER ADJUSTMENT TO THE
FORECAST IS POSSIBLE. IF THE SYSTEM DEEPENS FURTHER THAN CURRENTLY
ANTICIPATED...STORM FORCE WIND GUSTS COULD DEVELOP OVER PORTIONS OF
LAKE HURON. THOSE WITH INTERESTS IN THE GREAT LAKES MONDAY AND
MONDAY NIGHT SHOULD FOLLOW CHANGES IN THE FORECAST CLOSELY. A GALE
WATCH IS NOW IN EFFECT MONDAY AND MONDAY NIGHT FOR ALL MARINE AREAS.

&&

.AVIATION...ISSUED 103 PM EST SAT NOV 22 2014

//DISCUSSION...

LOW PRESSURE ORGANIZING OVER CENTRAL CANADA AND THE PLAINS STATES
TODAY WILL MAINTAIN MILDER SOUTHERLY WIND OVER SE MICHIGAN THROUGH
SUNDAY. LOW LEVEL WIND SHEAR REMAINS IN PLACE BELOW 2000 FEET IN
THIS PATTERN ENHANCED BY LIMITED BOUNDARY LAYER MIXING. CEILING
WILL BE NO BETTER THAN MVFR THROUGH THE PERIOD COMBINED WITH
INTERVALS OF IFR IN BOTH CEILING AND VISIBILITY DEPENDING ON MILD
AIR INTERACTIONS WITH SNOW COVER. THE LATEST OBSERVATIONAL DATA
SUGGESTS THIS IS MOST LIKELY SUNDAY MORNING AS INCREASING SURFACE
DEWPOINT COMBINES WITH THE NEXT SURGE OF RAIN SHOWERS. EXPECT THE
SHOWERS TO LAST OFF AND ON INTO SUNDAY AFTERNOON WITH A MODEST
IMPROVEMENT TO LOW END MVFR CEILING DURING THE DAY.

FOR DTW... PRECIPITATION TYPE WILL REMAIN FIRMLY IN THE FORM OF ALL
RAIN GOING FORWARD IN THE FORECAST TODAY THROUGH SUNDAY.
TEMPERATURES WILL CONTINUE A STEADY RISE EVEN AFTER SUNSET TONIGHT
WITH READINGS IN THE LOWER TO MID 40S BEFORE THE NEXT SURGE OF RAIN
SHOWERS BEGINS SUNDAY MORNING.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE TODAY THROUGH
  SUNDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR
     LHZ361>363-421-422-441>443-462>464.

LAKE ST CLAIR...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LEZ444.

&&

$$

SHORT TERM...BT
LONG TERM....HLO/MM
MARINE.......HLO
AVIATION.....BT


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 222120
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
420 PM EST SAT NOV 22 2014

.SHORT TERM... LATE AFTERNOON THROUGH TONIGHT

LOW PRESSURE DEVELOPING IN CENTRAL CANADA INTO THE NORTHERN PLAINS
STATES WILL MAINTAIN SOUTHERLY WIND AND A SUPPLY OF MILD AIR INTO SE
MICHIGAN THROUGH TONIGHT. AFTER A SLIGHT EARLY EVENING DROP BACK
TOWARD THE UPPER 30S...TEMPERATURES WILL EASILY BE ABLE TO REMAIN
STEADY OR SLOWLY RISE THROUGH THE LOWER AND MID 40S DURING THE
NIGHT. THIS MILD AIR IS ALSO MOISTURE LADEN WHICH WILL KEEP CLUSTERS
OF SHOWERS GOING AMID CLOUDY SKY WITH FOG AND DRIZZLE THROUGH THE
REGION.

MID AFTERNOON OBSERVATIONAL TRENDS FAVOR THE GREATEST COVERAGE OF
SHOWERS DURING LATE AFTERNOON THROUGH MID EVENING FOLLOWED BY A
BREAK DURING THE OVERNIGHT HOURS. SATELLITE AND MODEL ANALYSIS
FIELDS POINT TO ANOTHER WEAK WAVE ALOFT HELPING TO SUPPORT CLUSTERS
OF SHOWERS MOVING IN FROM NORTHERN INDIANA AND SW LOWER MICHIGAN.
THE SHORT WAVE FORCING WILL INTERACT WITH THE LOW LEVEL THETA-E
RIDGE BEING DRAWN INTO SE MICHIGAN AROUND THE 850 MB LEVEL. THE
ASSOCIATED MOISTURE TRANSPORT AND ELEVATED INSTABILITY IS MODEST
WHICH WILL LIMIT SHOWER INTENSITY...AND THE WAVE IS PROGRESSIVE
ENOUGH TO SLIDE THROUGH OUR AREA BY MIDNIGHT. THE PASSAGE OF THIS
FEATURE WILL THEN LIMIT PRECIPITATION TO PATCHY DRIZZLE WITHIN AREAS
OF FOG LIKELY TO FORM AS INCREASINGLY MILD AIR FLOWS OVER SNOW
COVERED GROUND. PLAN TO MONITOR OBSERVATIONAL TRENDS FOR DENSE FOG
POTENTIAL WHICH SHOULD BE LIMITED TO THE LAKE EFFECT ENHANCED M-59/I-
69 CORRIDOR AND POSSIBLY POINTS NORTH. SNOW COVER IS REPORTED TO BE
DIMINISHING RAPIDLY TO THE SOUTH THROUGH THE DETROIT METRO AREA
TOWARD THE OHIO BORDER.

&&

.LONG TERM...SUNDAY THROUGH NEXT SATURDAY

WARM AND RAINY PATTERN WILL CONTINUE SUNDAY AND EARLY MONDAY BEFORE
A COLD FRONT USHERS IN STRONG WINDS AND COLDER AIR LATER IN THE DAY.

LARGE UPPER TROUGH OVER THE PACIFIC NORTHWEST AND NORTHERN ROCKIES
WILL PROGRESS EAST TOWARDS THE GREAT LAKES...SCOOPING UP THE UPPER
LOW NOW SEEN ON WATER VAPOR OVER TEXAS IN THE PROCESS. THE REMNANTS
OF THE TEXAS WAVE LOOK TO LIFT NORTHWARD ACROSS LOWER MICHIGAN
SUNDAY NIGHT...WITH THE UPPER TROUGH AXIS FOLLOWING BY MONDAY NIGHT.
MODELS CONTINUE TO KEY IN ON A BAND OF ISENTROPIC LIFT PROGRESSING
NORTHWARD OVER SOUTHEAST MICHIGAN...WITH TIMING NOW RANGING FROM
MORNING TO AFTERNOON. THIS BAND OF ASCENT COMBINED WITH AMPLE
MOISTURE REMAINING OVER THE AREA SHOULD PROVIDE A GOOD COVERAGE OF
RAIN SHOWERS TOMORROW. OTHER CONCERN WILL BE CONTINUED WARM AIR
ADVECTION OVER THE COLD GROUND WHERE AT LEAST SOME SNOW COVER WILL
REMAIN. THIS COULD LEAD TO SOME FOG FORMATION...BUT THICKNESS MAY BE
ENOUGH TO HAVE AN IMPACT TO INTERESTS OTHER THAN AVIATION. BETTER
INFLUX OF MOISTURE AND ADDITIONAL WARM AIR LOOKS TO OCCUR LATER IN
THE DAY AND OVERNIGHT AS THE UPPER WAVE FROM TEXAS APPROACHES AND
THE LOW-LEVEL JET RAMPS UP OVER THE OHIO VALLEY AHEAD OF THE
ADVANCING UPPER TROUGH. PVA AHEAD OF THE APPROACHING WAVE COMBINED
WITH ASCENT ALONG THE WARM FRONT AND A COUPLED JET STRUCTURE SHOULD
PROVIDE DEEP LAYER FORCING. THIS WILL COMBINE WITH PW VALUES IN
EXCESS OF 1.0 INCHES TO PROVIDE A WIDESPREAD RAIN EVENT DURING THE
EVENING AND OVERNIGHT. QPF AMOUNTS LOOK TO RANGE BETWEEN 0.6 AND 1.0
INCH. FLOODING DOES NOT LOOK TO BE A CONCERN GIVEN LOW CURRENT LOW
RIVER LEVELS AND ONLY A SMALL AMOUNT OF SNOW COVER REMAINING.
TEMPERATURES WILL REMAIN VERY MILD...SUPPORTED BY H850 TEMPS
REACHING AROUND 8C IN THE WARM SECTOR. THIS SHOULD SUPPORT MAX TEMPS
IN THE UPPER 40S TO LOW 50S TOMORROW...WITH ONLY A SMALL DROP INTO
THE MID 40S FOR SUNDAY NIGHT.

MODELS SOLUTIONS CONTINUE TO DIVERGE WITH THE TRACK AND STRENGTH OF
THE SURFACE LOW AS IT LIFTS ACROSS WESTERN AND NORTHERN LOWER
MICHIGAN SUNDAY NIGHT INTO MONDAY. BIGGEST IMPLICATION WITH THIS IS
THE AFFECT ON AND UNCERTAINTY WITH THE WIND SPEED FORECAST. CURRENT
PREFERENCE GOES TO THE LAST FEW EURO/GEM SOLUTIONS DUE TO GOOD RUN
TO RUN CONSISTENCY AND GOOD OVERALL CONSENSUS WITHIN THE MODEL
GUIDANCE ENVELOPE. THIS HAS AN AVERAGE LOW PRESSURE OF 974MB. 12Z
NAM WAS NOT TOO FAR OFF THIS AND SHOWS GOOD DESCENT BEHIND THE COLD
FRONT ALONG ISENTROPIC SURFACES BETWEEN 280-290K (INTO THE GROUND).
THIS DESCENT COMBINED WITH STEEPENING LAPSE RATES/DEEPENING BOUNDARY
LAYER FROM STRONG COLD AIR ADVECTION...A TIGHT SURFACE PRESSURE
GRADIENT...AND A CORE OF 40-55 KNOT WINDS BETWEEN 900-800MB MAY
ALLOW VERY STRONG WIND GUSTS TO REACH THE SURFACE. CURRENT FORECAST
HIGHLIGHTS GUSTS 40 TO 45 MPH...WITH POTENTIAL TO REACH 50 MPH.
HEADLINES ARE A POSSIBILITY...BUT THERE IS STILL PLENTY OF TIME FOR
THINGS TO CHANGE. A FEW RUMBLES OF THUNDER MAY ALSO BE POSSIBLE
EARLY ON MONDAY IN THE WARM SECTOR AS INSTABILITY INCREASES...AND
POSSIBLY BECOMES SURFACE BASED. RAIN WILL CHANGE TO SNOW BEHIND THE
FRONT AS TEMPERATURES FALL DURING THE LATE AFTERNOON AND
EVENING...WITH LIGHT ACCUMULATIONS POSSIBLE IN THE EVENING AND THEN
OVERNIGHT AS LAKE EFFECT PROCESSES RAMP UP. DRIER AIR WILL FILTER
INTO THE REGION...POTENTIALLY CLEARING MOISTURE OUT OF THE DGZ IN
THE EVENING PER 12Z NAM. GEM/EURO TRY TO BRUSH THE NORTHWEST CORNER
OF THE FORECAST AREA WITH DEFORMATION LINGERING BEHIND THE DEPARTING
SYSTEM...SOMETHING TO KEEP AN EYE ON FOR THE SAGINAW VALLEY BUT
ACCUMULATIONS LOOK LIGHT AT THIS TIME.

LOW PRESSURE TRACKING NORTHEAST OF THE REGION WILL CONTINUE TO BRING
A LOW CHANCE FOR SNOW SHOWERS TO MICHIGAN ON TUESDAY. BREEZY
CONDITIONS WILL CONTINUE THROUGH THE DAY WITH GUSTS STILL IN THE 20
TO 30 MPH RANGE. HIGH PRESSURE CREEPING IN FROM THE SOUTHWEST WILL
BRING DRY CONDITIONS TO THE AREA...BUT ARCTIC AIR INTRUSION COMES
BACK IN PLACE WITH TEMPS 10 TO 15 DEGREES BELOW NORMAL. A CLIPPER
SYSTEM COULD BRING ACCUMULATING SNOW ON THANKSGIVING...MORE DETAILS
WHEN NWP COMES CLOSER TO A CONSENSUS.

&&

.MARINE...

SOUTHWEST WINDS WILL CONTINUE TO DECREASE THROUGH THE EARLY EVENING
ACROSS THE CENTRAL GREAT LAKES...ALLOWING WINDS WAVES OVER LAKE
HURON TO GRADUALLY SUBSIDE. WINDS WILL SHIFT MORE SOUTHERLY SUNDAY
AND SUNDAY NIGHT AS A LARGE LOW PRESSURE SYSTEM BEGINS TO LIFT
TOWARDS THE AREA FROM THE PLAINS. WARMER AIR WILL ALSO CONTINUE TO
SURGE INTO THE AREA...PROVIDING A FAIRLY STABLE ENVIRONMENT OVER THE
WARM LAKE WATERS. THIS SHOULD HELP LIMIT GUSTS TO THE 15 TO 25 KNOT
RANGE SUNDAY AND SUNDAY NIGHT.

THE LOW PRESSURE SYSTEM WILL LIFT ACROSS THE WESTERN AND NORTHERN
GREAT LAKES SUNDAY NIGHT THROUGH MONDAY...SENDING A STRONG COLD
FRONT ACROSS THE AREA MONDAY AFTERNOON. GALE FORCE WINDS LOOK LIKELY
BEHIND THE COLD FRONT MONDAY AND MONDAY NIGHT AS A TIGHT PRESSURE
GRADIENT DEVELOPS AND MUCH COLDER AIR RUSHES INTO THE AREA...WITH
POTENTIAL FOR WIND GUSTS TO EXCEED 45 KNOTS. THERE IS STILL SOME
UNCERTAINTY WITH HOW MUCH THIS SYSTEM WILL DEEPEN AND THE EXACT
TRACK IT WILL TAKE ACROSS THE GREAT LAKES. FURTHER ADJUSTMENT TO THE
FORECAST IS POSSIBLE. IF THE SYSTEM DEEPENS FURTHER THAN CURRENTLY
ANTICIPATED...STORM FORCE WIND GUSTS COULD DEVELOP OVER PORTIONS OF
LAKE HURON. THOSE WITH INTERESTS IN THE GREAT LAKES MONDAY AND
MONDAY NIGHT SHOULD FOLLOW CHANGES IN THE FORECAST CLOSELY. A GALE
WATCH IS NOW IN EFFECT MONDAY AND MONDAY NIGHT FOR ALL MARINE AREAS.

&&

.AVIATION...ISSUED 103 PM EST SAT NOV 22 2014

//DISCUSSION...

LOW PRESSURE ORGANIZING OVER CENTRAL CANADA AND THE PLAINS STATES
TODAY WILL MAINTAIN MILDER SOUTHERLY WIND OVER SE MICHIGAN THROUGH
SUNDAY. LOW LEVEL WIND SHEAR REMAINS IN PLACE BELOW 2000 FEET IN
THIS PATTERN ENHANCED BY LIMITED BOUNDARY LAYER MIXING. CEILING
WILL BE NO BETTER THAN MVFR THROUGH THE PERIOD COMBINED WITH
INTERVALS OF IFR IN BOTH CEILING AND VISIBILITY DEPENDING ON MILD
AIR INTERACTIONS WITH SNOW COVER. THE LATEST OBSERVATIONAL DATA
SUGGESTS THIS IS MOST LIKELY SUNDAY MORNING AS INCREASING SURFACE
DEWPOINT COMBINES WITH THE NEXT SURGE OF RAIN SHOWERS. EXPECT THE
SHOWERS TO LAST OFF AND ON INTO SUNDAY AFTERNOON WITH A MODEST
IMPROVEMENT TO LOW END MVFR CEILING DURING THE DAY.

FOR DTW... PRECIPITATION TYPE WILL REMAIN FIRMLY IN THE FORM OF ALL
RAIN GOING FORWARD IN THE FORECAST TODAY THROUGH SUNDAY.
TEMPERATURES WILL CONTINUE A STEADY RISE EVEN AFTER SUNSET TONIGHT
WITH READINGS IN THE LOWER TO MID 40S BEFORE THE NEXT SURGE OF RAIN
SHOWERS BEGINS SUNDAY MORNING.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE TODAY THROUGH
  SUNDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR
     LHZ361>363-421-422-441>443-462>464.

LAKE ST CLAIR...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WATCH FROM MONDAY MORNING THROUGH TUESDAY MORNING FOR LEZ444.

&&

$$

SHORT TERM...BT
LONG TERM....HLO/MM
MARINE.......HLO
AVIATION.....BT


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 221803
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
103 PM EST SAT NOV 22 2014

.AVIATION...

//DISCUSSION...

LOW PRESSURE ORGANIZING OVER CENTRAL CANADA AND THE PLAINS STATES
TODAY WILL MAINTAIN MILDER SOUTHERLY WIND OVER SE MICHIGAN THROUGH
SUNDAY. LOW LEVEL WIND SHEAR REMAINS IN PLACE BELOW 2000 FEET IN
THIS PATTERN ENHANCED BY LIMITED BOUNDARY LAYER MIXING. CEILING
WILL BE NO BETTER THAN MVFR THROUGH THE PERIOD COMBINED WITH
INTERVALS OF IFR IN BOTH CEILING AND VISIBILITY DEPENDING ON MILD
AIR INTERACTIONS WITH SNOW COVER. THE LATEST OBSERVATIONAL DATA
SUGGESTS THIS IS MOST LIKELY SUNDAY MORNING AS INCREASING SURFACE
DEWPOINT COMBINES WITH THE NEXT SURGE OF RAIN SHOWERS. EXPECT THE
SHOWERS TO LAST OFF AND ON INTO SUNDAY AFTERNOON WITH A MODEST
IMPROVEMENT TO LOW END MVFR CEILING DURING THE DAY.

FOR DTW... PRECIPITATION TYPE WILL REMAIN FIRMLY IN THE FORM OF ALL
RAIN GOING FORWARD IN THE FORECAST TODAY THROUGH SUNDAY.
TEMPERATURES WILL CONTINUE A STEADY RISE EVEN AFTER SUNSET TONIGHT
WITH READINGS IN THE LOWER TO MID 40S BEFORE THE NEXT SURGE OF RAIN
SHOWERS BEGINS SUNDAY MORNING.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE TODAY THROUGH
  SUNDAY.

&&

.PREV DISCUSSION...ISSUED 1130 AM EST SAT NOV 22 2014

UPDATE...

WARMER AIR SURGING INTO SE MICHIGAN HAS ELIMINATED THE FREEZING
RAIN HAZARD BY LIFTING TEMPS INTO THE MID AND UPPER 30S ACROSS
THE REGION. UPSTREAM OBSERVATIONS DURING THE LATE MORNING INDICATE
EVEN WARMER AIR ON OUR DOORSTEP WITH READINGS IN THE UPPER 40S TO
LOWER 50S ENTERING CENTRAL AND SOUTHERN INDIANA. WE WILL LIKELY
NOT WARM UP THAT MUCH BASED ON THE PACE OF SURFACE WARM ADVECTION
OVER SNOW COVER IN OUR AREA BUT MID TO UPPER 40S LOOK REACHABLE.

COVERAGE OF SHOWERS WILL CONTINUE DIMINISHING DURING THE
AFTERNOON WITH A DRIZZLE COMPONENT ADDED DUE TO MID LEVEL
SUBSIDENCE BETWEEN SHORT WAVES ALOFT. THIS WILL KEEP CONDITIONS
DAMP AND CLOUDY WITH FOG ALSO BECOMING MORE NOTICEABLE AS THE
INCREASINGLY MILD AIR FLOWS OVER THE SNOW COVER.

PREV DISCUSSION...ISSUED 330 AM EST SAT NOV 22 2014

SHORT TERM...TODAY AND TONIGHT

TEMPERATURES ARE STILL IN THE LOW TO MID 20S EARLY THIS
MORNING...WITH SURFACE DEW PTS IN THE LOWER TEENS.
WITH THIS AMOUNT OF LOW LEVEL DRY AIR IN PLACE...BOUNDARY LAYER WET
BULB TEMPERATURES LOOK TO REMAIN BELOW FREEZING THROUGH THE MORNING
HOURS...PER 00Z NAM. MEANWHILE...WATER VAPOR IMAGERY SHOWS MID LEVEL
WAVE/CIRCULATION LIFTING INTO THE WESTERN GREAT LAKES...WHICH WILL
ALLOW FOR SUBSTANTIAL SURGE OF WARM AND MOIST AIR TO ARRIVE THIS
MORNING...WITH 850 MB DEW POINTS RISING TO BETWEEN 4-5 C. THIS WILL
LEAD TO SOME INSTABILITY...AS SHOWLATER INDEX FALLS TO AROUND ZERO
WITH GOOD MID LEVEL (700-500 MB) LAPSE RATES IN EXCESS OF 7 C/KM
WORKING THROUGH SOUTHERN LOWER MICHIGAN. DUE TO THE CONVECTIVE
NATURE OF THE ACTIVITY...TOUGH TO GAUGE QPF AREAL COVERAGE...AS
ESPECIALLY THE 00Z GFS IS LIKELY OVERDONE. STILL...BASED ON UPSTREAM
RADAR TRENDS...65-80 PERCENT POPS APPEAR APPROPRIATE...AND HAVE
ELECTED TO EXTEND FREEZING RAIN ADVISORY SOUTH...AS A QUICK GLAZE OF
ICE APPEARS LIKELY WITH THE FROZEN GROUND. SELF-LIMITING
PROCESS/LATENT HEAT RELEASE FROM THE FREEZING RAIN WITH NO COLD AIR
FEED WILL ASSURE TRANSITION TO JUST COLD RAIN AS THE DEEP AND STRONG
SOUTHWEST FLOW OVERSPREADS THE AREA...AND THE WARMER RAIN DROPS TAKE
HOLD. ALTHOUGH ACTIVITY MAY TAPER OFF TO DRIZZLE THIS
AFTERNOON...ANOTHER DEEPER SURGE OF MOISTURE TONIGHT...PW VALUES
INCREASING TO 1 INCH SHOULD ASSURE FURTHER ADDITIONAL LIGHT
RAIN/DRIZZLE...AS MERGING HEIGHT FALLS TAKE PLACE OVER THE CENTRAL
CONUS...BACKING THE FLOW OVER THE MISSISSIPPI RIVER VALLEY. WITH
FORECASTED (SEE EURO) SURFACE DEW PTS OF 40 F COMING OVER COLD/SNOW
COVERED GROUND OVER SOUTHERN LOWER MICHIGAN...ZONES WILL CONTAIN
SOME MENTION OF FOG. THE COLD SNOW COVERED GROUND IS ALSO EXPECTED
TO INHIBIT THE MIXING DEPTHS TODAY...AND THINK WIND GUSTS WILL BE
HARD PRESSED TO EXCEED MUCH PAST 20 KNOTS...DESPITE THE GOOD LOW
LEVEL JET (50 KNOTS).

LONG TERM...

SUNDAY...COMPACT SOUTHERN STREAM MID LEVEL WAVE NOTED ON WATER VAPOR
THIS MORNING EJECTING EASTWARD ACROSS NORTHERN MEXICO WILL STEADILY
LIFT NORTHEAST AND EVENTUALLY ACROSS THE GREAT LAKES BY SUNDAY
NIGHT.  MOIST LOW LEVEL SOUTHERLY FLOW ALONG THE EASTERN FLANK OF
THE MAIN HEIGHT FALLS WILL MARK CONDITIONS LOCALLY IN ADVANCE OF
THIS SYSTEM ON SUNDAY.  A RENEWED PERIOD OF STRONGER MOIST
ISENTROPIC ASCENT WILL TRANSLATE FROM SOUTH TO NORTH ACROSS THE
REGION DURING THE FIRST HALF OF THE DAY.  THIS PROCESS WILL IMPROVE
THE OVERALL MOISTURE QUALITY /PW AROUND 1 INCH/...IN ADDITION TO
SUPPORTING SOME LIGHT SHOWER DEVELOPMENT DURING THIS TIME.  A BRIEF
LULL IN THE FORCING FOR MIDDAY WILL PROVIDE THE GREATEST WINDOW FOR
A BETTER THERMAL RESPONSE.  A BACKGROUND OF WEAK WARM AIR ADVECTION
WILL COUNTER THE LACK OF MIXING AND INSOLATION POTENTIAL...ALLOWING
HIGHS TO MAKE A RUN TOWARD THE 50 DEGREE MARK.

SUNDAY NIGHT...STRONG MID LEVEL DYNAMICS ANCHORED BY STOUT LEFT EXIT
REGION UPPER JET FORCING...DIVERGENCE AND INCREASING CVA ATTENDANT
TO THE INBOUND WAVE WILL SWEEP ACROSS SE MICHIGAN SUNDAY NIGHT.
THIS FORCING INTO THE EXISTING VERY MOIST AMBIENT ENVIRONMENT WILL
RESULT IN A 6-9 HOUR PERIOD OF WIDESPREAD RAINFALL FOR THE ENTIRE
REGION OVERNIGHT.  QPF AMOUNTS WITHIN THE .5" TO .75" RANGE LOOK
ATTAINABLE GIVEN THE UNDERLYING STRENGTH OF ASCENT...MOISTURE DEPTH
AND OVERALL RESIDENCE TIME.  A FIRM SOUTHEAST GRADIENT WILL CONTAIN
TEMPERATURES IN THE LOWER AND MIDDLE 40S THROUGH THE NIGHT.

MONDAY...00Z NAM REMAINS OUTSIDE THE MODEL CONSENSUS WHICH HOLDS
WITH A MUCH DEEPER SURFACE LOW AS IT TRACKS FROM THE SOUTH END OF
LAKE MICHIGAN THROUGH NORTHERN LAKE HURON DURING THIS TIME.  00Z GFS
SEEMINGLY TOO AGGRESSIVE WITH THE RESPONSE /966 MB CENTER AT 18Z MON
NORTH OF THE STRAITS/...OWING TO MORE PRONOUNCED PHASING OF THE LEAD
PV FEATURE WITH A TRAILING NORTHERN STREAM TROUGH THAT BECOMES
NEGATIVELY TILTED.  THE NET RESULT IS A MORE SIZABLE DIFFERENCE IN
HANDLING THE DETAILS IN THE WAKE OF THE EXITING MAIN MOISTURE PLUME
HEADING INTO MONDAY.  SLIVER OF MILDER PRE-COLD FRONTAL AIR WILL
EXIST MONDAY MORNING...THE TRAILING COLD FRONTAL PASSAGE MOST LIKELY
COMMENCING DURING THE LATTER HALF OF THE DAY.  AT THIS POINT...MAIN
ELEMENT OF CONCERN BECOMES THE WIND POTENTIAL MONDAY AFTERNOON AND
EVENING...AS THE ENSUING ADVECTIVE PROCESS BUILDS THE CONVECTIVE
LAYER DEPTH INTO AN ALREADY FIRM WIND FIELD JUST OFF THE SURFACE.  A
PERIOD OF GOOD 280-285K ISENTROPIC DESCENT WITH 35 TO 40KT WINDS
WITHIN THIS LEVEL WOULD SUGGEST PEAK GUSTS IN EXCESS OF 35 MPH ARE
ATTAINABLE...WITH AN UPTICK TO HEADLINE WORTHY GUST POTENTIAL
CERTAINLY PLAUSIBLE.  WINDOW FOR STRONG CONVERGENCE ALONG THE
FRONTAL SLOPE AND WITH THE PASSAGE OF THE TRAILING WAVE WILL
MAINTAIN A CHANCE FOR SHOWERS INTO MONDAY...PARTICULARLY DURING THE
FIRST HALF OF THE DAY.  PRE-FRONTAL TEMPERATURES PEAK IN THE UPPER
40S-LOWER 50S...STRONGER COLD AIR ADVECTION AWAITING THE BETTER
HEIGHT FALLS TOWARD EVENING.

TUESDAY AND BEYOND...SUBSTANTIAL SOUTHWARD EXPANSION OF THE LOWER
HEIGHT FIELD WILL SPELL ANOTHER EXTENDED STRETCH OF BELOW NORMAL
TEMPERATURES STARTING TUESDAY.  PLACEMENT OF AN ENERGETIC NORTHERN
PACIFIC JET CORE SOUTHEAST AND NEAR/OVER THE GREAT LAKES WILL BRING
THE POTENTIAL FOR A PERIODICALLY ACTIVE PATTERN THROUGH THE UPCOMING
HOLIDAY WEEKEND.  POTENTIAL FOR LIGHT SNOW SHOWERS TUESDAY WITHIN A
MOIST CYCLONIC FLOW...AUGMENTED BY THE MOISTURE FLUX OFF LAKE
MICHIGAN.  WEAK SHORTWAVE WORKING THROUGH THE NORTHWEST FLOW IS
FORECAST TO DEEPEN WITHIN FAVORABLE UPPER JET SUPPORT ON
WEDNESDAY...LONG RANGE MODEL GUIDANCE ALLOWING THIS WAVE TO SHIFT
INTO SOUTHEAST MICHIGAN BY THANKSGIVING.  WHILE SUBJECT TO CHANGE
YET AT THIS TIME SCALE...LATEST TRENDS WOULD BRING THE POTENTIAL FOR
A LIGHT ACCUMULATING SNOWFALL WITH THIS SYSTEM FOR THE HOLIDAY.

MARINE...

SOUTHWEST WINDS WILL REMAIN STRONG THROUGH THE FIRST HALF OF TODAY.
GUSTS TO GALES OR NEAR GALES WILL EXIST OVER CENTRAL PORTIONS OF
LAKE HURON THROUGH THE MORNING PERIOD.  WINDS WILL EASE SLIGHTLY
THIS AFTERNOON AS THE OVERALL GRADIENT SLACKENS.  A MODEST SOUTHERLY
WIND WILL EXIST TONIGHT AND SUNDAY IN ADVANCE OF STRENGTHENING LOW
PRESSURE.  SOME INCREASE IN SOUTHEAST WINDS WILL OCCUR AS THIS LOW
TRACKS FROM SOUTHERN LAKE MICHIGAN TO THE STRAITS SUNDAY NIGHT.  THE
COMBINATION OF AN INCREASING GRADIENT AND THE RETURN OF COLDER AIR
WILL BRING THE POTENTIAL FOR GALES ACROSS ALL MARINE AREAS BY MONDAY
AFTERNOON AND EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LHZ421-441.

     SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR LHZ442.

LAKE ST CLAIR...NONE.

MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....BT
UPDATE.......BT
SHORT TERM...SF
LONG TERM....MR
MARINE.......MR


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 221803
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
103 PM EST SAT NOV 22 2014

.AVIATION...

//DISCUSSION...

LOW PRESSURE ORGANIZING OVER CENTRAL CANADA AND THE PLAINS STATES
TODAY WILL MAINTAIN MILDER SOUTHERLY WIND OVER SE MICHIGAN THROUGH
SUNDAY. LOW LEVEL WIND SHEAR REMAINS IN PLACE BELOW 2000 FEET IN
THIS PATTERN ENHANCED BY LIMITED BOUNDARY LAYER MIXING. CEILING
WILL BE NO BETTER THAN MVFR THROUGH THE PERIOD COMBINED WITH
INTERVALS OF IFR IN BOTH CEILING AND VISIBILITY DEPENDING ON MILD
AIR INTERACTIONS WITH SNOW COVER. THE LATEST OBSERVATIONAL DATA
SUGGESTS THIS IS MOST LIKELY SUNDAY MORNING AS INCREASING SURFACE
DEWPOINT COMBINES WITH THE NEXT SURGE OF RAIN SHOWERS. EXPECT THE
SHOWERS TO LAST OFF AND ON INTO SUNDAY AFTERNOON WITH A MODEST
IMPROVEMENT TO LOW END MVFR CEILING DURING THE DAY.

FOR DTW... PRECIPITATION TYPE WILL REMAIN FIRMLY IN THE FORM OF ALL
RAIN GOING FORWARD IN THE FORECAST TODAY THROUGH SUNDAY.
TEMPERATURES WILL CONTINUE A STEADY RISE EVEN AFTER SUNSET TONIGHT
WITH READINGS IN THE LOWER TO MID 40S BEFORE THE NEXT SURGE OF RAIN
SHOWERS BEGINS SUNDAY MORNING.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET.

* HIGH CONFIDENCE IN RAIN AS PRECIPITATION TYPE TODAY THROUGH
  SUNDAY.

&&

.PREV DISCUSSION...ISSUED 1130 AM EST SAT NOV 22 2014

UPDATE...

WARMER AIR SURGING INTO SE MICHIGAN HAS ELIMINATED THE FREEZING
RAIN HAZARD BY LIFTING TEMPS INTO THE MID AND UPPER 30S ACROSS
THE REGION. UPSTREAM OBSERVATIONS DURING THE LATE MORNING INDICATE
EVEN WARMER AIR ON OUR DOORSTEP WITH READINGS IN THE UPPER 40S TO
LOWER 50S ENTERING CENTRAL AND SOUTHERN INDIANA. WE WILL LIKELY
NOT WARM UP THAT MUCH BASED ON THE PACE OF SURFACE WARM ADVECTION
OVER SNOW COVER IN OUR AREA BUT MID TO UPPER 40S LOOK REACHABLE.

COVERAGE OF SHOWERS WILL CONTINUE DIMINISHING DURING THE
AFTERNOON WITH A DRIZZLE COMPONENT ADDED DUE TO MID LEVEL
SUBSIDENCE BETWEEN SHORT WAVES ALOFT. THIS WILL KEEP CONDITIONS
DAMP AND CLOUDY WITH FOG ALSO BECOMING MORE NOTICEABLE AS THE
INCREASINGLY MILD AIR FLOWS OVER THE SNOW COVER.

PREV DISCUSSION...ISSUED 330 AM EST SAT NOV 22 2014

SHORT TERM...TODAY AND TONIGHT

TEMPERATURES ARE STILL IN THE LOW TO MID 20S EARLY THIS
MORNING...WITH SURFACE DEW PTS IN THE LOWER TEENS.
WITH THIS AMOUNT OF LOW LEVEL DRY AIR IN PLACE...BOUNDARY LAYER WET
BULB TEMPERATURES LOOK TO REMAIN BELOW FREEZING THROUGH THE MORNING
HOURS...PER 00Z NAM. MEANWHILE...WATER VAPOR IMAGERY SHOWS MID LEVEL
WAVE/CIRCULATION LIFTING INTO THE WESTERN GREAT LAKES...WHICH WILL
ALLOW FOR SUBSTANTIAL SURGE OF WARM AND MOIST AIR TO ARRIVE THIS
MORNING...WITH 850 MB DEW POINTS RISING TO BETWEEN 4-5 C. THIS WILL
LEAD TO SOME INSTABILITY...AS SHOWLATER INDEX FALLS TO AROUND ZERO
WITH GOOD MID LEVEL (700-500 MB) LAPSE RATES IN EXCESS OF 7 C/KM
WORKING THROUGH SOUTHERN LOWER MICHIGAN. DUE TO THE CONVECTIVE
NATURE OF THE ACTIVITY...TOUGH TO GAUGE QPF AREAL COVERAGE...AS
ESPECIALLY THE 00Z GFS IS LIKELY OVERDONE. STILL...BASED ON UPSTREAM
RADAR TRENDS...65-80 PERCENT POPS APPEAR APPROPRIATE...AND HAVE
ELECTED TO EXTEND FREEZING RAIN ADVISORY SOUTH...AS A QUICK GLAZE OF
ICE APPEARS LIKELY WITH THE FROZEN GROUND. SELF-LIMITING
PROCESS/LATENT HEAT RELEASE FROM THE FREEZING RAIN WITH NO COLD AIR
FEED WILL ASSURE TRANSITION TO JUST COLD RAIN AS THE DEEP AND STRONG
SOUTHWEST FLOW OVERSPREADS THE AREA...AND THE WARMER RAIN DROPS TAKE
HOLD. ALTHOUGH ACTIVITY MAY TAPER OFF TO DRIZZLE THIS
AFTERNOON...ANOTHER DEEPER SURGE OF MOISTURE TONIGHT...PW VALUES
INCREASING TO 1 INCH SHOULD ASSURE FURTHER ADDITIONAL LIGHT
RAIN/DRIZZLE...AS MERGING HEIGHT FALLS TAKE PLACE OVER THE CENTRAL
CONUS...BACKING THE FLOW OVER THE MISSISSIPPI RIVER VALLEY. WITH
FORECASTED (SEE EURO) SURFACE DEW PTS OF 40 F COMING OVER COLD/SNOW
COVERED GROUND OVER SOUTHERN LOWER MICHIGAN...ZONES WILL CONTAIN
SOME MENTION OF FOG. THE COLD SNOW COVERED GROUND IS ALSO EXPECTED
TO INHIBIT THE MIXING DEPTHS TODAY...AND THINK WIND GUSTS WILL BE
HARD PRESSED TO EXCEED MUCH PAST 20 KNOTS...DESPITE THE GOOD LOW
LEVEL JET (50 KNOTS).

LONG TERM...

SUNDAY...COMPACT SOUTHERN STREAM MID LEVEL WAVE NOTED ON WATER VAPOR
THIS MORNING EJECTING EASTWARD ACROSS NORTHERN MEXICO WILL STEADILY
LIFT NORTHEAST AND EVENTUALLY ACROSS THE GREAT LAKES BY SUNDAY
NIGHT.  MOIST LOW LEVEL SOUTHERLY FLOW ALONG THE EASTERN FLANK OF
THE MAIN HEIGHT FALLS WILL MARK CONDITIONS LOCALLY IN ADVANCE OF
THIS SYSTEM ON SUNDAY.  A RENEWED PERIOD OF STRONGER MOIST
ISENTROPIC ASCENT WILL TRANSLATE FROM SOUTH TO NORTH ACROSS THE
REGION DURING THE FIRST HALF OF THE DAY.  THIS PROCESS WILL IMPROVE
THE OVERALL MOISTURE QUALITY /PW AROUND 1 INCH/...IN ADDITION TO
SUPPORTING SOME LIGHT SHOWER DEVELOPMENT DURING THIS TIME.  A BRIEF
LULL IN THE FORCING FOR MIDDAY WILL PROVIDE THE GREATEST WINDOW FOR
A BETTER THERMAL RESPONSE.  A BACKGROUND OF WEAK WARM AIR ADVECTION
WILL COUNTER THE LACK OF MIXING AND INSOLATION POTENTIAL...ALLOWING
HIGHS TO MAKE A RUN TOWARD THE 50 DEGREE MARK.

SUNDAY NIGHT...STRONG MID LEVEL DYNAMICS ANCHORED BY STOUT LEFT EXIT
REGION UPPER JET FORCING...DIVERGENCE AND INCREASING CVA ATTENDANT
TO THE INBOUND WAVE WILL SWEEP ACROSS SE MICHIGAN SUNDAY NIGHT.
THIS FORCING INTO THE EXISTING VERY MOIST AMBIENT ENVIRONMENT WILL
RESULT IN A 6-9 HOUR PERIOD OF WIDESPREAD RAINFALL FOR THE ENTIRE
REGION OVERNIGHT.  QPF AMOUNTS WITHIN THE .5" TO .75" RANGE LOOK
ATTAINABLE GIVEN THE UNDERLYING STRENGTH OF ASCENT...MOISTURE DEPTH
AND OVERALL RESIDENCE TIME.  A FIRM SOUTHEAST GRADIENT WILL CONTAIN
TEMPERATURES IN THE LOWER AND MIDDLE 40S THROUGH THE NIGHT.

MONDAY...00Z NAM REMAINS OUTSIDE THE MODEL CONSENSUS WHICH HOLDS
WITH A MUCH DEEPER SURFACE LOW AS IT TRACKS FROM THE SOUTH END OF
LAKE MICHIGAN THROUGH NORTHERN LAKE HURON DURING THIS TIME.  00Z GFS
SEEMINGLY TOO AGGRESSIVE WITH THE RESPONSE /966 MB CENTER AT 18Z MON
NORTH OF THE STRAITS/...OWING TO MORE PRONOUNCED PHASING OF THE LEAD
PV FEATURE WITH A TRAILING NORTHERN STREAM TROUGH THAT BECOMES
NEGATIVELY TILTED.  THE NET RESULT IS A MORE SIZABLE DIFFERENCE IN
HANDLING THE DETAILS IN THE WAKE OF THE EXITING MAIN MOISTURE PLUME
HEADING INTO MONDAY.  SLIVER OF MILDER PRE-COLD FRONTAL AIR WILL
EXIST MONDAY MORNING...THE TRAILING COLD FRONTAL PASSAGE MOST LIKELY
COMMENCING DURING THE LATTER HALF OF THE DAY.  AT THIS POINT...MAIN
ELEMENT OF CONCERN BECOMES THE WIND POTENTIAL MONDAY AFTERNOON AND
EVENING...AS THE ENSUING ADVECTIVE PROCESS BUILDS THE CONVECTIVE
LAYER DEPTH INTO AN ALREADY FIRM WIND FIELD JUST OFF THE SURFACE.  A
PERIOD OF GOOD 280-285K ISENTROPIC DESCENT WITH 35 TO 40KT WINDS
WITHIN THIS LEVEL WOULD SUGGEST PEAK GUSTS IN EXCESS OF 35 MPH ARE
ATTAINABLE...WITH AN UPTICK TO HEADLINE WORTHY GUST POTENTIAL
CERTAINLY PLAUSIBLE.  WINDOW FOR STRONG CONVERGENCE ALONG THE
FRONTAL SLOPE AND WITH THE PASSAGE OF THE TRAILING WAVE WILL
MAINTAIN A CHANCE FOR SHOWERS INTO MONDAY...PARTICULARLY DURING THE
FIRST HALF OF THE DAY.  PRE-FRONTAL TEMPERATURES PEAK IN THE UPPER
40S-LOWER 50S...STRONGER COLD AIR ADVECTION AWAITING THE BETTER
HEIGHT FALLS TOWARD EVENING.

TUESDAY AND BEYOND...SUBSTANTIAL SOUTHWARD EXPANSION OF THE LOWER
HEIGHT FIELD WILL SPELL ANOTHER EXTENDED STRETCH OF BELOW NORMAL
TEMPERATURES STARTING TUESDAY.  PLACEMENT OF AN ENERGETIC NORTHERN
PACIFIC JET CORE SOUTHEAST AND NEAR/OVER THE GREAT LAKES WILL BRING
THE POTENTIAL FOR A PERIODICALLY ACTIVE PATTERN THROUGH THE UPCOMING
HOLIDAY WEEKEND.  POTENTIAL FOR LIGHT SNOW SHOWERS TUESDAY WITHIN A
MOIST CYCLONIC FLOW...AUGMENTED BY THE MOISTURE FLUX OFF LAKE
MICHIGAN.  WEAK SHORTWAVE WORKING THROUGH THE NORTHWEST FLOW IS
FORECAST TO DEEPEN WITHIN FAVORABLE UPPER JET SUPPORT ON
WEDNESDAY...LONG RANGE MODEL GUIDANCE ALLOWING THIS WAVE TO SHIFT
INTO SOUTHEAST MICHIGAN BY THANKSGIVING.  WHILE SUBJECT TO CHANGE
YET AT THIS TIME SCALE...LATEST TRENDS WOULD BRING THE POTENTIAL FOR
A LIGHT ACCUMULATING SNOWFALL WITH THIS SYSTEM FOR THE HOLIDAY.

MARINE...

SOUTHWEST WINDS WILL REMAIN STRONG THROUGH THE FIRST HALF OF TODAY.
GUSTS TO GALES OR NEAR GALES WILL EXIST OVER CENTRAL PORTIONS OF
LAKE HURON THROUGH THE MORNING PERIOD.  WINDS WILL EASE SLIGHTLY
THIS AFTERNOON AS THE OVERALL GRADIENT SLACKENS.  A MODEST SOUTHERLY
WIND WILL EXIST TONIGHT AND SUNDAY IN ADVANCE OF STRENGTHENING LOW
PRESSURE.  SOME INCREASE IN SOUTHEAST WINDS WILL OCCUR AS THIS LOW
TRACKS FROM SOUTHERN LAKE MICHIGAN TO THE STRAITS SUNDAY NIGHT.  THE
COMBINATION OF AN INCREASING GRADIENT AND THE RETURN OF COLDER AIR
WILL BRING THE POTENTIAL FOR GALES ACROSS ALL MARINE AREAS BY MONDAY
AFTERNOON AND EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LHZ421-441.

     SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR LHZ442.

LAKE ST CLAIR...NONE.

MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....BT
UPDATE.......BT
SHORT TERM...SF
LONG TERM....MR
MARINE.......MR


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 221630
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1130 AM EST SAT NOV 22 2014

.UPDATE...

WARMER AIR SURGING INTO SE MICHIGAN HAS ELIMINATED THE FREEZING
RAIN HAZARD BY LIFTING TEMPS INTO THE MID AND UPPER 30S ACROSS
THE REGION. UPSTREAM OBSERVATIONS DURING THE LATE MORNING INDICATE
EVEN WARMER AIR ON OUR DOORSTEP WITH READINGS IN THE UPPER 40S TO
LOWER 50S ENTERING CENTRAL AND SOUTHERN INDIANA. WE WILL LIKELY
NOT WARM UP THAT MUCH BASED ON THE PACE OF SURFACE WARM ADVECTION
OVER SNOW COVER IN OUR AREA BUT MID TO UPPER 40S LOOK REACHABLE.

COVERAGE OF SHOWERS WILL CONTINUE DIMINISHING DURING THE
AFTERNOON WITH A DRIZZLE COMPONENT ADDED DUE TO MID LEVEL
SUBSIDENCE BETWEEN SHORT WAVES ALOFT. THIS WILL KEEP CONDITIONS
DAMP AND CLOUDY WITH FOG ALSO BECOMING MORE NOTICEABLE AS THE
INCREASINGLY MILD AIR FLOWS OVER THE SNOW COVER.

&&

.AVIATION...ISSUED 652 AM EST SAT NOV 22 2014

//DISCUSSION...

A STRONG SOUTHWEST LOW LEVEL JET (50+ KNOTS) AT THE 2000 TO 3000
FOOT IS PUMPING MOIST AIR INTO LOWER MICHIGAN...AND TAF SITES SHOULD
BE LOCKED IN THE MVFR CATEGORY FOR MOST/ALL OF THE PERIOD. A PERIOD
OF LIGHT FREEZING RAIN CAN BE EXPECTED THIS MORNING BEFORE CHANGING
OVER TO COLD RAIN/DRIZZLE. FURTHER MOISTENING OFF THE LOW LEVELS
THROUGH THE DAY WILL LEAD TO FOG CONCERNS TONIGHT AND LIKELY IFR
CONDITIONS...AS ADDITIONAL LIGHT RAIN/DRIZZLE CONTINUES. PREVIOUS
MENTIONED LOW LEVEL JET WILL LEAD TO WIND SHEAR...AS COLD SURFACE
HINDERS BOUNDARY LAYER DEPTHS AND WIND SPEEDS AT THE SURFACE.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET.

* HIGH CONFIDENCE PRECIPITATION WILL CHANGE TO RAIN LATE IN THE
  MORNING...WITH RAIN OVER THE REMAINDER OF THE TAF PERIOD

&&

.PREV DISCUSSION...ISSUED 330 AM EST SAT NOV 22 2014

SHORT TERM...TODAY AND TONIGHT

TEMPERATURES ARE STILL IN THE LOW TO MID 20S EARLY THIS
MORNING...WITH SURFACE DEW PTS IN THE LOWER TEENS.
WITH THIS AMOUNT OF LOW LEVEL DRY AIR IN PLACE...BOUNDARY LAYER WET
BULB TEMPERATURES LOOK TO REMAIN BELOW FREEZING THROUGH THE MORNING
HOURS...PER 00Z NAM. MEANWHILE...WATER VAPOR IMAGERY SHOWS MID LEVEL
WAVE/CIRCULATION LIFTING INTO THE WESTERN GREAT LAKES...WHICH WILL
ALLOW FOR SUBSTANTIAL SURGE OF WARM AND MOIST AIR TO ARRIVE THIS
MORNING...WITH 850 MB DEW POINTS RISING TO BETWEEN 4-5 C. THIS WILL
LEAD TO SOME INSTABILITY...AS SHOWLATER INDEX FALLS TO AROUND ZERO
.WITH GOOD MID LEVEL (700-500 MB) LAPSE RATES IN EXCESS OF 7 C/KM
WORKING THROUGH SOUTHERN LOWER MICHIGAN. DUE TO THE CONVECTIVE
NATURE OF THE ACTIVITY...TOUGH TO GAUGE QPF AREAL COVERAGE...AS
ESPECIALLY THE 00Z GFS IS LIKELY OVERDONE. STILL...BASED ON UPSTREAM
RADAR TRENDS...65-80 PERCENT POPS APPEAR APPROPRIATE...AND HAVE
ELECTED TO EXTEND FREEZING RAIN ADVISORY SOUTH...AS A QUICK GLAZE OF
ICE APPEARS LIKELY WITH THE FROZEN GROUND. SELF-LIMITING
PROCESS/LATENT HEAT RELEASE FROM THE FREEZING RAIN WITH NO COLD AIR
FEED WILL ASSURE TRANSITION TO JUST COLD RAIN AS THE DEEP AND STRONG
SOUTHWEST FLOW OVERSPREADS THE AREA...AND THE WARMER RAIN DROPS TAKE
HOLD. ALTHOUGH ACTIVITY MAY TAPER OFF TO DRIZZLE THIS
AFTERNOON...ANOTHER DEEPER SURGE OF MOISTURE TONIGHT...PW VALUES
INCREASING TO 1 INCH SHOULD ASSURE FURTHER ADDITIONAL LIGHT
RAIN/DRIZZLE...AS MERGING HEIGHT FALLS TAKE PLACE OVER THE CENTRAL
CONUS...BACKING THE FLOW OVER THE MISSISSIPPI RIVER VALLEY. WITH
FORECASTED (SEE EURO) SURFACE DEW PTS OF 40 F COMING OVER COLD/SNOW
COVERED GROUND OVER SOUTHERN LOWER MICHIGAN...ZONES WILL CONTAIN
SOME MENTION OF FOG. THE COLD SNOW COVERED GROUND IS ALSO EXPECTED
TO INHIBIT THE MIXING DEPTHS TODAY...AND THINK WIND GUSTS WILL BE
HARD PRESSED TO EXCEED MUCH PAST 20 KNOTS...DESPITE THE GOOD LOW
LEVEL JET (50 KNOTS).

LONG TERM...

SUNDAY...COMPACT SOUTHERN STREAM MID LEVEL WAVE NOTED ON WATER VAPOR
THIS MORNING EJECTING EASTWARD ACROSS NORTHERN MEXICO WILL STEADILY
LIFT NORTHEAST AND EVENTUALLY ACROSS THE GREAT LAKES BY SUNDAY
NIGHT.  MOIST LOW LEVEL SOUTHERLY FLOW ALONG THE EASTERN FLANK OF
THE MAIN HEIGHT FALLS WILL MARK CONDITIONS LOCALLY IN ADVANCE OF
THIS SYSTEM ON SUNDAY.  A RENEWED PERIOD OF STRONGER MOIST
ISENTROPIC ASCENT WILL TRANSLATE FROM SOUTH TO NORTH ACROSS THE
REGION DURING THE FIRST HALF OF THE DAY.  THIS PROCESS WILL IMPROVE
THE OVERALL MOISTURE QUALITY /PW AROUND 1 INCH/...IN ADDITION TO
SUPPORTING SOME LIGHT SHOWER DEVELOPMENT DURING THIS TIME.  A BRIEF
LULL IN THE FORCING FOR MIDDAY WILL PROVIDE THE GREATEST WINDOW FOR
A BETTER THERMAL RESPONSE.  A BACKGROUND OF WEAK WARM AIR ADVECTION
WILL COUNTER THE LACK OF MIXING AND INSOLATION POTENTIAL...ALLOWING
HIGHS TO MAKE A RUN TOWARD THE 50 DEGREE MARK.

SUNDAY NIGHT...STRONG MID LEVEL DYNAMICS ANCHORED BY STOUT LEFT EXIT
REGION UPPER JET FORCING...DIVERGENCE AND INCREASING CVA ATTENDANT
TO THE INBOUND WAVE WILL SWEEP ACROSS SE MICHIGAN SUNDAY NIGHT.
THIS FORCING INTO THE EXISTING VERY MOIST AMBIENT ENVIRONMENT WILL
RESULT IN A 6-9 HOUR PERIOD OF WIDESPREAD RAINFALL FOR THE ENTIRE
REGION OVERNIGHT.  QPF AMOUNTS WITHIN THE .5" TO .75" RANGE LOOK
ATTAINABLE GIVEN THE UNDERLYING STRENGTH OF ASCENT...MOISTURE DEPTH
AND OVERALL RESIDENCE TIME.  A FIRM SOUTHEAST GRADIENT WILL CONTAIN
TEMPERATURES IN THE LOWER AND MIDDLE 40S THROUGH THE NIGHT.

MONDAY...00Z NAM REMAINS OUTSIDE THE MODEL CONSENSUS WHICH HOLDS
WITH A MUCH DEEPER SURFACE LOW AS IT TRACKS FROM THE SOUTH END OF
LAKE MICHIGAN THROUGH NORTHERN LAKE HURON DURING THIS TIME.  00Z GFS
SEEMINGLY TOO AGGRESSIVE WITH THE RESPONSE /966 MB CENTER AT 18Z MON
NORTH OF THE STRAITS/...OWING TO MORE PRONOUNCED PHASING OF THE LEAD
PV FEATURE WITH A TRAILING NORTHERN STREAM TROUGH THAT BECOMES
NEGATIVELY TILTED.  THE NET RESULT IS A MORE SIZABLE DIFFERENCE IN
HANDLING THE DETAILS IN THE WAKE OF THE EXITING MAIN MOISTURE PLUME
HEADING INTO MONDAY.  SLIVER OF MILDER PRE-COLD FRONTAL AIR WILL
EXIST MONDAY MORNING...THE TRAILING COLD FRONTAL PASSAGE MOST LIKELY
COMMENCING DURING THE LATTER HALF OF THE DAY.  AT THIS POINT...MAIN
ELEMENT OF CONCERN BECOMES THE WIND POTENTIAL MONDAY AFTERNOON AND
EVENING...AS THE ENSUING ADVECTIVE PROCESS BUILDS THE CONVECTIVE
LAYER DEPTH INTO AN ALREADY FIRM WIND FIELD JUST OFF THE SURFACE.  A
PERIOD OF GOOD 280-285K ISENTROPIC DESCENT WITH 35 TO 40KT WINDS
WITHIN THIS LEVEL WOULD SUGGEST PEAK GUSTS IN EXCESS OF 35 MPH ARE
ATTAINABLE...WITH AN UPTICK TO HEADLINE WORTHY GUST POTENTIAL
CERTAINLY PLAUSIBLE.  WINDOW FOR STRONG CONVERGENCE ALONG THE
FRONTAL SLOPE AND WITH THE PASSAGE OF THE TRAILING WAVE WILL
MAINTAIN A CHANCE FOR SHOWERS INTO MONDAY...PARTICULARLY DURING THE
FIRST HALF OF THE DAY.  PRE-FRONTAL TEMPERATURES PEAK IN THE UPPER
40S-LOWER 50S...STRONGER COLD AIR ADVECTION AWAITING THE BETTER
HEIGHT FALLS TOWARD EVENING.

TUESDAY AND BEYOND...SUBSTANTIAL SOUTHWARD EXPANSION OF THE LOWER
HEIGHT FIELD WILL SPELL ANOTHER EXTENDED STRETCH OF BELOW NORMAL
TEMPERATURES STARTING TUESDAY.  PLACEMENT OF AN ENERGETIC NORTHERN
PACIFIC JET CORE SOUTHEAST AND NEAR/OVER THE GREAT LAKES WILL BRING
THE POTENTIAL FOR A PERIODICALLY ACTIVE PATTERN THROUGH THE UPCOMING
HOLIDAY WEEKEND.  POTENTIAL FOR LIGHT SNOW SHOWERS TUESDAY WITHIN A
MOIST CYCLONIC FLOW...AUGMENTED BY THE MOISTURE FLUX OFF LAKE
MICHIGAN.  WEAK SHORTWAVE WORKING THROUGH THE NORTHWEST FLOW IS
FORECAST TO DEEPEN WITHIN FAVORABLE UPPER JET SUPPORT ON
WEDNESDAY...LONG RANGE MODEL GUIDANCE ALLOWING THIS WAVE TO SHIFT
INTO SOUTHEAST MICHIGAN BY THANKSGIVING.  WHILE SUBJECT TO CHANGE
YET AT THIS TIME SCALE...LATEST TRENDS WOULD BRING THE POTENTIAL FOR
A LIGHT ACCUMULATING SNOWFALL WITH THIS SYSTEM FOR THE HOLIDAY.

MARINE...

SOUTHWEST WINDS WILL REMAIN STRONG THROUGH THE FIRST HALF OF TODAY.
GUSTS TO GALES OR NEAR GALES WILL EXIST OVER CENTRAL PORTIONS OF
LAKE HURON THROUGH THE MORNING PERIOD.  WINDS WILL EASE SLIGHTLY
THIS AFTERNOON AS THE OVERALL GRADIENT SLACKENS.  A MODEST SOUTHERLY
WIND WILL EXIST TONIGHT AND SUNDAY IN ADVANCE OF STRENGTHENING LOW
PRESSURE.  SOME INCREASE IN SOUTHEAST WINDS WILL OCCUR AS THIS LOW
TRACKS FROM SOUTHERN LAKE MICHIGAN TO THE STRAITS SUNDAY NIGHT.  THE
COMBINATION OF AN INCREASING GRADIENT AND THE RETURN OF COLDER AIR
WILL BRING THE POTENTIAL FOR GALES ACROSS ALL MARINE AREAS BY MONDAY
AFTERNOON AND EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LHZ421-441.

     SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR LHZ442.

LAKE ST CLAIR...NONE.

MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

UPDATE.......BT
AVIATION.....SF
SHORT TERM...SF
LONG TERM....MR
MARINE.......MR


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 221630
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1130 AM EST SAT NOV 22 2014

.UPDATE...

WARMER AIR SURGING INTO SE MICHIGAN HAS ELIMINATED THE FREEZING
RAIN HAZARD BY LIFTING TEMPS INTO THE MID AND UPPER 30S ACROSS
THE REGION. UPSTREAM OBSERVATIONS DURING THE LATE MORNING INDICATE
EVEN WARMER AIR ON OUR DOORSTEP WITH READINGS IN THE UPPER 40S TO
LOWER 50S ENTERING CENTRAL AND SOUTHERN INDIANA. WE WILL LIKELY
NOT WARM UP THAT MUCH BASED ON THE PACE OF SURFACE WARM ADVECTION
OVER SNOW COVER IN OUR AREA BUT MID TO UPPER 40S LOOK REACHABLE.

COVERAGE OF SHOWERS WILL CONTINUE DIMINISHING DURING THE
AFTERNOON WITH A DRIZZLE COMPONENT ADDED DUE TO MID LEVEL
SUBSIDENCE BETWEEN SHORT WAVES ALOFT. THIS WILL KEEP CONDITIONS
DAMP AND CLOUDY WITH FOG ALSO BECOMING MORE NOTICEABLE AS THE
INCREASINGLY MILD AIR FLOWS OVER THE SNOW COVER.

&&

.AVIATION...ISSUED 652 AM EST SAT NOV 22 2014

//DISCUSSION...

A STRONG SOUTHWEST LOW LEVEL JET (50+ KNOTS) AT THE 2000 TO 3000
FOOT IS PUMPING MOIST AIR INTO LOWER MICHIGAN...AND TAF SITES SHOULD
BE LOCKED IN THE MVFR CATEGORY FOR MOST/ALL OF THE PERIOD. A PERIOD
OF LIGHT FREEZING RAIN CAN BE EXPECTED THIS MORNING BEFORE CHANGING
OVER TO COLD RAIN/DRIZZLE. FURTHER MOISTENING OFF THE LOW LEVELS
THROUGH THE DAY WILL LEAD TO FOG CONCERNS TONIGHT AND LIKELY IFR
CONDITIONS...AS ADDITIONAL LIGHT RAIN/DRIZZLE CONTINUES. PREVIOUS
MENTIONED LOW LEVEL JET WILL LEAD TO WIND SHEAR...AS COLD SURFACE
HINDERS BOUNDARY LAYER DEPTHS AND WIND SPEEDS AT THE SURFACE.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET.

* HIGH CONFIDENCE PRECIPITATION WILL CHANGE TO RAIN LATE IN THE
  MORNING...WITH RAIN OVER THE REMAINDER OF THE TAF PERIOD

&&

.PREV DISCUSSION...ISSUED 330 AM EST SAT NOV 22 2014

SHORT TERM...TODAY AND TONIGHT

TEMPERATURES ARE STILL IN THE LOW TO MID 20S EARLY THIS
MORNING...WITH SURFACE DEW PTS IN THE LOWER TEENS.
WITH THIS AMOUNT OF LOW LEVEL DRY AIR IN PLACE...BOUNDARY LAYER WET
BULB TEMPERATURES LOOK TO REMAIN BELOW FREEZING THROUGH THE MORNING
HOURS...PER 00Z NAM. MEANWHILE...WATER VAPOR IMAGERY SHOWS MID LEVEL
WAVE/CIRCULATION LIFTING INTO THE WESTERN GREAT LAKES...WHICH WILL
ALLOW FOR SUBSTANTIAL SURGE OF WARM AND MOIST AIR TO ARRIVE THIS
MORNING...WITH 850 MB DEW POINTS RISING TO BETWEEN 4-5 C. THIS WILL
LEAD TO SOME INSTABILITY...AS SHOWLATER INDEX FALLS TO AROUND ZERO
.WITH GOOD MID LEVEL (700-500 MB) LAPSE RATES IN EXCESS OF 7 C/KM
WORKING THROUGH SOUTHERN LOWER MICHIGAN. DUE TO THE CONVECTIVE
NATURE OF THE ACTIVITY...TOUGH TO GAUGE QPF AREAL COVERAGE...AS
ESPECIALLY THE 00Z GFS IS LIKELY OVERDONE. STILL...BASED ON UPSTREAM
RADAR TRENDS...65-80 PERCENT POPS APPEAR APPROPRIATE...AND HAVE
ELECTED TO EXTEND FREEZING RAIN ADVISORY SOUTH...AS A QUICK GLAZE OF
ICE APPEARS LIKELY WITH THE FROZEN GROUND. SELF-LIMITING
PROCESS/LATENT HEAT RELEASE FROM THE FREEZING RAIN WITH NO COLD AIR
FEED WILL ASSURE TRANSITION TO JUST COLD RAIN AS THE DEEP AND STRONG
SOUTHWEST FLOW OVERSPREADS THE AREA...AND THE WARMER RAIN DROPS TAKE
HOLD. ALTHOUGH ACTIVITY MAY TAPER OFF TO DRIZZLE THIS
AFTERNOON...ANOTHER DEEPER SURGE OF MOISTURE TONIGHT...PW VALUES
INCREASING TO 1 INCH SHOULD ASSURE FURTHER ADDITIONAL LIGHT
RAIN/DRIZZLE...AS MERGING HEIGHT FALLS TAKE PLACE OVER THE CENTRAL
CONUS...BACKING THE FLOW OVER THE MISSISSIPPI RIVER VALLEY. WITH
FORECASTED (SEE EURO) SURFACE DEW PTS OF 40 F COMING OVER COLD/SNOW
COVERED GROUND OVER SOUTHERN LOWER MICHIGAN...ZONES WILL CONTAIN
SOME MENTION OF FOG. THE COLD SNOW COVERED GROUND IS ALSO EXPECTED
TO INHIBIT THE MIXING DEPTHS TODAY...AND THINK WIND GUSTS WILL BE
HARD PRESSED TO EXCEED MUCH PAST 20 KNOTS...DESPITE THE GOOD LOW
LEVEL JET (50 KNOTS).

LONG TERM...

SUNDAY...COMPACT SOUTHERN STREAM MID LEVEL WAVE NOTED ON WATER VAPOR
THIS MORNING EJECTING EASTWARD ACROSS NORTHERN MEXICO WILL STEADILY
LIFT NORTHEAST AND EVENTUALLY ACROSS THE GREAT LAKES BY SUNDAY
NIGHT.  MOIST LOW LEVEL SOUTHERLY FLOW ALONG THE EASTERN FLANK OF
THE MAIN HEIGHT FALLS WILL MARK CONDITIONS LOCALLY IN ADVANCE OF
THIS SYSTEM ON SUNDAY.  A RENEWED PERIOD OF STRONGER MOIST
ISENTROPIC ASCENT WILL TRANSLATE FROM SOUTH TO NORTH ACROSS THE
REGION DURING THE FIRST HALF OF THE DAY.  THIS PROCESS WILL IMPROVE
THE OVERALL MOISTURE QUALITY /PW AROUND 1 INCH/...IN ADDITION TO
SUPPORTING SOME LIGHT SHOWER DEVELOPMENT DURING THIS TIME.  A BRIEF
LULL IN THE FORCING FOR MIDDAY WILL PROVIDE THE GREATEST WINDOW FOR
A BETTER THERMAL RESPONSE.  A BACKGROUND OF WEAK WARM AIR ADVECTION
WILL COUNTER THE LACK OF MIXING AND INSOLATION POTENTIAL...ALLOWING
HIGHS TO MAKE A RUN TOWARD THE 50 DEGREE MARK.

SUNDAY NIGHT...STRONG MID LEVEL DYNAMICS ANCHORED BY STOUT LEFT EXIT
REGION UPPER JET FORCING...DIVERGENCE AND INCREASING CVA ATTENDANT
TO THE INBOUND WAVE WILL SWEEP ACROSS SE MICHIGAN SUNDAY NIGHT.
THIS FORCING INTO THE EXISTING VERY MOIST AMBIENT ENVIRONMENT WILL
RESULT IN A 6-9 HOUR PERIOD OF WIDESPREAD RAINFALL FOR THE ENTIRE
REGION OVERNIGHT.  QPF AMOUNTS WITHIN THE .5" TO .75" RANGE LOOK
ATTAINABLE GIVEN THE UNDERLYING STRENGTH OF ASCENT...MOISTURE DEPTH
AND OVERALL RESIDENCE TIME.  A FIRM SOUTHEAST GRADIENT WILL CONTAIN
TEMPERATURES IN THE LOWER AND MIDDLE 40S THROUGH THE NIGHT.

MONDAY...00Z NAM REMAINS OUTSIDE THE MODEL CONSENSUS WHICH HOLDS
WITH A MUCH DEEPER SURFACE LOW AS IT TRACKS FROM THE SOUTH END OF
LAKE MICHIGAN THROUGH NORTHERN LAKE HURON DURING THIS TIME.  00Z GFS
SEEMINGLY TOO AGGRESSIVE WITH THE RESPONSE /966 MB CENTER AT 18Z MON
NORTH OF THE STRAITS/...OWING TO MORE PRONOUNCED PHASING OF THE LEAD
PV FEATURE WITH A TRAILING NORTHERN STREAM TROUGH THAT BECOMES
NEGATIVELY TILTED.  THE NET RESULT IS A MORE SIZABLE DIFFERENCE IN
HANDLING THE DETAILS IN THE WAKE OF THE EXITING MAIN MOISTURE PLUME
HEADING INTO MONDAY.  SLIVER OF MILDER PRE-COLD FRONTAL AIR WILL
EXIST MONDAY MORNING...THE TRAILING COLD FRONTAL PASSAGE MOST LIKELY
COMMENCING DURING THE LATTER HALF OF THE DAY.  AT THIS POINT...MAIN
ELEMENT OF CONCERN BECOMES THE WIND POTENTIAL MONDAY AFTERNOON AND
EVENING...AS THE ENSUING ADVECTIVE PROCESS BUILDS THE CONVECTIVE
LAYER DEPTH INTO AN ALREADY FIRM WIND FIELD JUST OFF THE SURFACE.  A
PERIOD OF GOOD 280-285K ISENTROPIC DESCENT WITH 35 TO 40KT WINDS
WITHIN THIS LEVEL WOULD SUGGEST PEAK GUSTS IN EXCESS OF 35 MPH ARE
ATTAINABLE...WITH AN UPTICK TO HEADLINE WORTHY GUST POTENTIAL
CERTAINLY PLAUSIBLE.  WINDOW FOR STRONG CONVERGENCE ALONG THE
FRONTAL SLOPE AND WITH THE PASSAGE OF THE TRAILING WAVE WILL
MAINTAIN A CHANCE FOR SHOWERS INTO MONDAY...PARTICULARLY DURING THE
FIRST HALF OF THE DAY.  PRE-FRONTAL TEMPERATURES PEAK IN THE UPPER
40S-LOWER 50S...STRONGER COLD AIR ADVECTION AWAITING THE BETTER
HEIGHT FALLS TOWARD EVENING.

TUESDAY AND BEYOND...SUBSTANTIAL SOUTHWARD EXPANSION OF THE LOWER
HEIGHT FIELD WILL SPELL ANOTHER EXTENDED STRETCH OF BELOW NORMAL
TEMPERATURES STARTING TUESDAY.  PLACEMENT OF AN ENERGETIC NORTHERN
PACIFIC JET CORE SOUTHEAST AND NEAR/OVER THE GREAT LAKES WILL BRING
THE POTENTIAL FOR A PERIODICALLY ACTIVE PATTERN THROUGH THE UPCOMING
HOLIDAY WEEKEND.  POTENTIAL FOR LIGHT SNOW SHOWERS TUESDAY WITHIN A
MOIST CYCLONIC FLOW...AUGMENTED BY THE MOISTURE FLUX OFF LAKE
MICHIGAN.  WEAK SHORTWAVE WORKING THROUGH THE NORTHWEST FLOW IS
FORECAST TO DEEPEN WITHIN FAVORABLE UPPER JET SUPPORT ON
WEDNESDAY...LONG RANGE MODEL GUIDANCE ALLOWING THIS WAVE TO SHIFT
INTO SOUTHEAST MICHIGAN BY THANKSGIVING.  WHILE SUBJECT TO CHANGE
YET AT THIS TIME SCALE...LATEST TRENDS WOULD BRING THE POTENTIAL FOR
A LIGHT ACCUMULATING SNOWFALL WITH THIS SYSTEM FOR THE HOLIDAY.

MARINE...

SOUTHWEST WINDS WILL REMAIN STRONG THROUGH THE FIRST HALF OF TODAY.
GUSTS TO GALES OR NEAR GALES WILL EXIST OVER CENTRAL PORTIONS OF
LAKE HURON THROUGH THE MORNING PERIOD.  WINDS WILL EASE SLIGHTLY
THIS AFTERNOON AS THE OVERALL GRADIENT SLACKENS.  A MODEST SOUTHERLY
WIND WILL EXIST TONIGHT AND SUNDAY IN ADVANCE OF STRENGTHENING LOW
PRESSURE.  SOME INCREASE IN SOUTHEAST WINDS WILL OCCUR AS THIS LOW
TRACKS FROM SOUTHERN LAKE MICHIGAN TO THE STRAITS SUNDAY NIGHT.  THE
COMBINATION OF AN INCREASING GRADIENT AND THE RETURN OF COLDER AIR
WILL BRING THE POTENTIAL FOR GALES ACROSS ALL MARINE AREAS BY MONDAY
AFTERNOON AND EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LHZ421-441.

     SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR LHZ442.

LAKE ST CLAIR...NONE.

MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

UPDATE.......BT
AVIATION.....SF
SHORT TERM...SF
LONG TERM....MR
MARINE.......MR


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 221152
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
652 AM EST SAT NOV 22 2014

.AVIATION...

//DISCUSSION...

A STRONG SOUTHWEST LOW LEVEL JET (50+ KNOTS) AT THE 2000 TO 3000
FOOT IS PUMPING MOIST AIR INTO LOWER MICHIGAN...AND TAF SITES SHOULD
BE LOCKED IN THE MVFR CATEGORY FOR MOST/ALL OF THE PERIOD. A PERIOD
OF LIGHT FREEZING RAIN CAN BE EXPECTED THIS MORNING BEFORE CHANGING
OVER TO COLD RAIN/DRIZZLE. FURTHER MOISTENING OFF THE LOW LEVELS
THROUGH THE DAY WILL LEAD TO FOG CONCERNS TONIGHT AND LIKELY IFR
CONDITIONS...AS ADDITIONAL LIGHT RAIN/DRIZZLE CONTINUES. PREVIOUS
MENTIONED LOW LEVEL JET WILL LEAD TO WIND SHEAR...AS COLD SURFACE
HINDERS BOUNDARY LAYER DEPTHS AND WIND SPEEDS AT THE SURFACE.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET.

* HIGH CONFIDENCE PRECIPITATION WILL CHANGE TO RAIN LATE IN THE
  MORNING...WITH RAIN OVER THE REMAINDER OF THE TAF PERIOD

&&

.PREV DISCUSSION...ISSUED 330 AM EST SAT NOV 22 2014

SHORT TERM...TODAY AND TONIGHT

TEMPERATURES ARE STILL IN THE LOW TO MID 20S EARLY THIS
MORNING...WITH SURFACE DEW PTS IN THE LOWER TEENS.
WITH THIS AMOUNT OF LOW LEVEL DRY AIR IN PLACE...BOUNDARY LAYER WET
BULB TEMPERATURES LOOK TO REMAIN BELOW FREEZING THROUGH THE MORNING
HOURS...PER 00Z NAM. MEANWHILE...WATER VAPOR IMAGERY SHOWS MID LEVEL
WAVE/CIRCULATION LIFTING INTO THE WESTERN GREAT LAKES...WHICH WILL
ALLOW FOR SUBSTANTIAL SURGE OF WARM AND MOIST AIR TO ARRIVE THIS
MORNING...WITH 850 MB DEW POINTS RISING TO BETWEEN 4-5 C. THIS WILL
LEAD TO SOME INSTABILITY...AS SHOWLATER INDEX FALLS TO AROUND ZERO
..WITH GOOD MID LEVEL (700-500 MB) LAPSE RATES IN EXCESS OF 7 C/KM
WORKING THROUGH SOUTHERN LOWER MICHIGAN. DUE TO THE CONVECTIVE
NATURE OF THE ACTIVITY...TOUGH TO GAUGE QPF AREAL COVERAGE...AS
ESPECIALLY THE 00Z GFS IS LIKELY OVERDONE. STILL...BASED ON UPSTREAM
RADAR TRENDS...65-80 PERCENT POPS APPEAR APPROPRIATE...AND HAVE
ELECTED TO EXTEND FREEZING RAIN ADVISORY SOUTH...AS A QUICK GLAZE OF
ICE APPEARS LIKELY WITH THE FROZEN GROUND. SELF-LIMITING
PROCESS/LATENT HEAT RELEASE FROM THE FREEZING RAIN WITH NO COLD AIR
FEED WILL ASSURE TRANSITION TO JUST COLD RAIN AS THE DEEP AND STRONG
SOUTHWEST FLOW OVERSPREADS THE AREA...AND THE WARMER RAIN DROPS TAKE
HOLD. ALTHOUGH ACTIVITY MAY TAPER OFF TO DRIZZLE THIS
AFTERNOON...ANOTHER DEEPER SURGE OF MOISTURE TONIGHT...PW VALUES
INCREASING TO 1 INCH SHOULD ASSURE FURTHER ADDITIONAL LIGHT
RAIN/DRIZZLE...AS MERGING HEIGHT FALLS TAKE PLACE OVER THE CENTRAL
CONUS...BACKING THE FLOW OVER THE MISSISSIPPI RIVER VALLEY. WITH
FORECASTED (SEE EURO) SURFACE DEW PTS OF 40 F COMING OVER COLD/SNOW
COVERED GROUND OVER SOUTHERN LOWER MICHIGAN...ZONES WILL CONTAIN
SOME MENTION OF FOG. THE COLD SNOW COVERED GROUND IS ALSO EXPECTED
TO INHIBIT THE MIXING DEPTHS TODAY...AND THINK WIND GUSTS WILL BE
HARD PRESSED TO EXCEED MUCH PAST 20 KNOTS...DESPITE THE GOOD LOW
LEVEL JET (50 KNOTS).

LONG TERM...

SUNDAY...COMPACT SOUTHERN STREAM MID LEVEL WAVE NOTED ON WATER VAPOR
THIS MORNING EJECTING EASTWARD ACROSS NORTHERN MEXICO WILL STEADILY
LIFT NORTHEAST AND EVENTUALLY ACROSS THE GREAT LAKES BY SUNDAY
NIGHT.  MOIST LOW LEVEL SOUTHERLY FLOW ALONG THE EASTERN FLANK OF
THE MAIN HEIGHT FALLS WILL MARK CONDITIONS LOCALLY IN ADVANCE OF
THIS SYSTEM ON SUNDAY.  A RENEWED PERIOD OF STRONGER MOIST
ISENTROPIC ASCENT WILL TRANSLATE FROM SOUTH TO NORTH ACROSS THE
REGION DURING THE FIRST HALF OF THE DAY.  THIS PROCESS WILL IMPROVE
THE OVERALL MOISTURE QUALITY /PW AROUND 1 INCH/...IN ADDITION TO
SUPPORTING SOME LIGHT SHOWER DEVELOPMENT DURING THIS TIME.  A BRIEF
LULL IN THE FORCING FOR MIDDAY WILL PROVIDE THE GREATEST WINDOW FOR
A BETTER THERMAL RESPONSE.  A BACKGROUND OF WEAK WARM AIR ADVECTION
WILL COUNTER THE LACK OF MIXING AND INSOLATION POTENTIAL...ALLOWING
HIGHS TO MAKE A RUN TOWARD THE 50 DEGREE MARK.

SUNDAY NIGHT...STRONG MID LEVEL DYNAMICS ANCHORED BY STOUT LEFT EXIT
REGION UPPER JET FORCING...DIVERGENCE AND INCREASING CVA ATTENDANT
TO THE INBOUND WAVE WILL SWEEP ACROSS SE MICHIGAN SUNDAY NIGHT.
THIS FORCING INTO THE EXISTING VERY MOIST AMBIENT ENVIRONMENT WILL
RESULT IN A 6-9 HOUR PERIOD OF WIDESPREAD RAINFALL FOR THE ENTIRE
REGION OVERNIGHT.  QPF AMOUNTS WITHIN THE .5" TO .75" RANGE LOOK
ATTAINABLE GIVEN THE UNDERLYING STRENGTH OF ASCENT...MOISTURE DEPTH
AND OVERALL RESIDENCE TIME.  A FIRM SOUTHEAST GRADIENT WILL CONTAIN
TEMPERATURES IN THE LOWER AND MIDDLE 40S THROUGH THE NIGHT.

MONDAY...00Z NAM REMAINS OUTSIDE THE MODEL CONSENSUS WHICH HOLDS
WITH A MUCH DEEPER SURFACE LOW AS IT TRACKS FROM THE SOUTH END OF
LAKE MICHIGAN THROUGH NORTHERN LAKE HURON DURING THIS TIME.  00Z GFS
SEEMINGLY TOO AGGRESSIVE WITH THE RESPONSE /966 MB CENTER AT 18Z MON
NORTH OF THE STRAITS/...OWING TO MORE PRONOUNCED PHASING OF THE LEAD
PV FEATURE WITH A TRAILING NORTHERN STREAM TROUGH THAT BECOMES
NEGATIVELY TILTED.  THE NET RESULT IS A MORE SIZABLE DIFFERENCE IN
HANDLING THE DETAILS IN THE WAKE OF THE EXITING MAIN MOISTURE PLUME
HEADING INTO MONDAY.  SLIVER OF MILDER PRE-COLD FRONTAL AIR WILL
EXIST MONDAY MORNING...THE TRAILING COLD FRONTAL PASSAGE MOST LIKELY
COMMENCING DURING THE LATTER HALF OF THE DAY.  AT THIS POINT...MAIN
ELEMENT OF CONCERN BECOMES THE WIND POTENTIAL MONDAY AFTERNOON AND
EVENING...AS THE ENSUING ADVECTIVE PROCESS BUILDS THE CONVECTIVE
LAYER DEPTH INTO AN ALREADY FIRM WIND FIELD JUST OFF THE SURFACE.  A
PERIOD OF GOOD 280-285K ISENTROPIC DESCENT WITH 35 TO 40KT WINDS
WITHIN THIS LEVEL WOULD SUGGEST PEAK GUSTS IN EXCESS OF 35 MPH ARE
ATTAINABLE...WITH AN UPTICK TO HEADLINE WORTHY GUST POTENTIAL
CERTAINLY PLAUSIBLE.  WINDOW FOR STRONG CONVERGENCE ALONG THE
FRONTAL SLOPE AND WITH THE PASSAGE OF THE TRAILING WAVE WILL
MAINTAIN A CHANCE FOR SHOWERS INTO MONDAY...PARTICULARLY DURING THE
FIRST HALF OF THE DAY.  PRE-FRONTAL TEMPERATURES PEAK IN THE UPPER
40S-LOWER 50S...STRONGER COLD AIR ADVECTION AWAITING THE BETTER
HEIGHT FALLS TOWARD EVENING.

TUESDAY AND BEYOND...SUBSTANTIAL SOUTHWARD EXPANSION OF THE LOWER
HEIGHT FIELD WILL SPELL ANOTHER EXTENDED STRETCH OF BELOW NORMAL
TEMPERATURES STARTING TUESDAY.  PLACEMENT OF AN ENERGETIC NORTHERN
PACIFIC JET CORE SOUTHEAST AND NEAR/OVER THE GREAT LAKES WILL BRING
THE POTENTIAL FOR A PERIODICALLY ACTIVE PATTERN THROUGH THE UPCOMING
HOLIDAY WEEKEND.  POTENTIAL FOR LIGHT SNOW SHOWERS TUESDAY WITHIN A
MOIST CYCLONIC FLOW...AUGMENTED BY THE MOISTURE FLUX OFF LAKE
MICHIGAN.  WEAK SHORTWAVE WORKING THROUGH THE NORTHWEST FLOW IS
FORECAST TO DEEPEN WITHIN FAVORABLE UPPER JET SUPPORT ON
WEDNESDAY...LONG RANGE MODEL GUIDANCE ALLOWING THIS WAVE TO SHIFT
INTO SOUTHEAST MICHIGAN BY THANKSGIVING.  WHILE SUBJECT TO CHANGE
YET AT THIS TIME SCALE...LATEST TRENDS WOULD BRING THE POTENTIAL FOR
A LIGHT ACCUMULATING SNOWFALL WITH THIS SYSTEM FOR THE HOLIDAY.

MARINE...

SOUTHWEST WINDS WILL REMAIN STRONG THROUGH THE FIRST HALF OF TODAY.
GUSTS TO GALES OR NEAR GALES WILL EXIST OVER CENTRAL PORTIONS OF
LAKE HURON THROUGH THE MORNING PERIOD.  WINDS WILL EASE SLIGHTLY
THIS AFTERNOON AS THE OVERALL GRADIENT SLACKENS.  A MODEST SOUTHERLY
WIND WILL EXIST TONIGHT AND SUNDAY IN ADVANCE OF STRENGTHENING LOW
PRESSURE.  SOME INCREASE IN SOUTHEAST WINDS WILL OCCUR AS THIS LOW
TRACKS FROM SOUTHERN LAKE MICHIGAN TO THE STRAITS SUNDAY NIGHT.  THE
COMBINATION OF AN INCREASING GRADIENT AND THE RETURN OF COLDER AIR
WILL BRING THE POTENTIAL FOR GALES ACROSS ALL MARINE AREAS BY MONDAY
AFTERNOON AND EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...FREEZING RAIN ADVISORY UNTIL 11 AM EST THIS MORNING FOR MIZ060>063-
     068>070-075-076-082-083.

     FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR MIZ047>049-053>055.

LAKE HURON...GALE WARNING UNTIL 11 AM EST THIS MORNING FOR LHZ362-363-421-462-
     463.

     SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR LHZ441-442.

     SMALL CRAFT ADVISORY UNTIL 11 AM EST THIS MORNING FOR LHZ422.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....SF
SHORT TERM...SF
LONG TERM....MR
MARINE.......MR

YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS
ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 220830
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
330 AM EST SAT NOV 22 2014

.SHORT TERM...TODAY AND TONIGHT

TEMPERATURES ARE STILL IN THE LOW TO MID 20S EARLY THIS
MORNING...WITH SURFACE DEW PTS IN THE LOWER TEENS.
WITH THIS AMOUNT OF LOW LEVEL DRY AIR IN PLACE...BOUNDARY LAYER WET
BULB TEMPERATURES LOOK TO REMAIN BELOW FREEZING THROUGH THE MORNING
HOURS...PER 00Z NAM. MEANWHILE...WATER VAPOR IMAGERY SHOWS MID LEVEL
WAVE/CIRCULATION LIFTING INTO THE WESTERN GREAT LAKES...WHICH WILL
ALLOW FOR SUBSTANTIAL SURGE OF WARM AND MOIST AIR TO ARRIVE THIS
MORNING...WITH 850 MB DEW POINTS RISING TO BETWEEN 4-5 C. THIS WILL
LEAD TO SOME INSTABILITY...AS SHOWLATER INDEX FALLS TO AROUND ZERO
...WITH GOOD MID LEVEL (700-500 MB) LAPSE RATES IN EXCESS OF 7 C/KM
WORKING THROUGH SOUTHERN LOWER MICHIGAN. DUE TO THE CONVECTIVE
NATURE OF THE ACTIVITY...TOUGH TO GAUGE QPF AREAL COVERAGE...AS
ESPECIALLY THE 00Z GFS IS LIKELY OVERDONE. STILL...BASED ON UPSTREAM
RADAR TRENDS...65-80 PERCENT POPS APPEAR APPROPRIATE...AND HAVE
ELECTED TO EXTEND FREEZING RAIN ADVISORY SOUTH...AS A QUICK GLAZE OF
ICE APPEARS LIKELY WITH THE FROZEN GROUND. SELF-LIMITING
PROCESS/LATENT HEAT RELEASE FROM THE FREEZING RAIN WITH NO COLD AIR
FEED WILL ASSURE TRANSITION TO JUST COLD RAIN AS THE DEEP AND STRONG
SOUTHWEST FLOW OVERSPREADS THE AREA...AND THE WARMER RAIN DROPS TAKE
HOLD. ALTHOUGH ACTIVITY MAY TAPER OFF TO DRIZZLE THIS
AFTERNOON...ANOTHER DEEPER SURGE OF MOISTURE TONIGHT...PW VALUES
INCREASING TO 1 INCH SHOULD ASSURE FURTHER ADDITIONAL LIGHT
RAIN/DRIZZLE...AS MERGING HEIGHT FALLS TAKE PLACE OVER THE CENTRAL
CONUS...BACKING THE FLOW OVER THE MISSISSIPPI RIVER VALLEY. WITH
FORECASTED (SEE EURO) SURFACE DEW PTS OF 40 F COMING OVER COLD/SNOW
COVERED GROUND OVER SOUTHERN LOWER MICHIGAN...ZONES WILL CONTAIN
SOME MENTION OF FOG. THE COLD SNOW COVERED GROUND IS ALSO EXPECTED
TO INHIBIT THE MIXING DEPTHS TODAY...AND THINK WIND GUSTS WILL BE
HARD PRESSED TO EXCEED MUCH PAST 20 KNOTS...DESPITE THE GOOD LOW
LEVEL JET (50 KNOTS).

&&

.LONG TERM...

SUNDAY...COMPACT SOUTHERN STREAM MID LEVEL WAVE NOTED ON WATER VAPOR
THIS MORNING EJECTING EASTWARD ACROSS NORTHERN MEXICO WILL STEADILY
LIFT NORTHEAST AND EVENTUALLY ACROSS THE GREAT LAKES BY SUNDAY
NIGHT.  MOIST LOW LEVEL SOUTHERLY FLOW ALONG THE EASTERN FLANK OF
THE MAIN HEIGHT FALLS WILL MARK CONDITIONS LOCALLY IN ADVANCE OF
THIS SYSTEM ON SUNDAY.  A RENEWED PERIOD OF STRONGER MOIST
ISENTROPIC ASCENT WILL TRANSLATE FROM SOUTH TO NORTH ACROSS THE
REGION DURING THE FIRST HALF OF THE DAY.  THIS PROCESS WILL IMPROVE
THE OVERALL MOISTURE QUALITY /PW AROUND 1 INCH/...IN ADDITION TO
SUPPORTING SOME LIGHT SHOWER DEVELOPMENT DURING THIS TIME.  A BRIEF
LULL IN THE FORCING FOR MIDDAY WILL PROVIDE THE GREATEST WINDOW FOR
A BETTER THERMAL RESPONSE.  A BACKGROUND OF WEAK WARM AIR ADVECTION
WILL COUNTER THE LACK OF MIXING AND INSOLATION POTENTIAL...ALLOWING
HIGHS TO MAKE A RUN TOWARD THE 50 DEGREE MARK.

SUNDAY NIGHT...STRONG MID LEVEL DYNAMICS ANCHORED BY STOUT LEFT EXIT
REGION UPPER JET FORCING...DIVERGENCE AND INCREASING CVA ATTENDANT
TO THE INBOUND WAVE WILL SWEEP ACROSS SE MICHIGAN SUNDAY NIGHT.
THIS FORCING INTO THE EXISTING VERY MOIST AMBIENT ENVIRONMENT WILL
RESULT IN A 6-9 HOUR PERIOD OF WIDESPREAD RAINFALL FOR THE ENTIRE
REGION OVERNIGHT.  QPF AMOUNTS WITHIN THE .5" TO .75" RANGE LOOK
ATTAINABLE GIVEN THE UNDERLYING STRENGTH OF ASCENT...MOISTURE DEPTH
AND OVERALL RESIDENCE TIME.  A FIRM SOUTHEAST GRADIENT WILL CONTAIN
TEMPERATURES IN THE LOWER AND MIDDLE 40S THROUGH THE NIGHT.

MONDAY...00Z NAM REMAINS OUTSIDE THE MODEL CONSENSUS WHICH HOLDS
WITH A MUCH DEEPER SURFACE LOW AS IT TRACKS FROM THE SOUTH END OF
LAKE MICHIGAN THROUGH NORTHERN LAKE HURON DURING THIS TIME.  00Z GFS
SEEMINGLY TOO AGGRESSIVE WITH THE RESPONSE /966 MB CENTER AT 18Z MON
NORTH OF THE STRAITS/...OWING TO MORE PRONOUNCED PHASING OF THE LEAD
PV FEATURE WITH A TRAILING NORTHERN STREAM TROUGH THAT BECOMES
NEGATIVELY TILTED.  THE NET RESULT IS A MORE SIZABLE DIFFERENCE IN
HANDLING THE DETAILS IN THE WAKE OF THE EXITING MAIN MOISTURE PLUME
HEADING INTO MONDAY.  SLIVER OF MILDER PRE-COLD FRONTAL AIR WILL
EXIST MONDAY MORNING...THE TRAILING COLD FRONTAL PASSAGE MOST LIKELY
COMMENCING DURING THE LATTER HALF OF THE DAY.  AT THIS POINT...MAIN
ELEMENT OF CONCERN BECOMES THE WIND POTENTIAL MONDAY AFTERNOON AND
EVENING...AS THE ENSUING ADVECTIVE PROCESS BUILDS THE CONVECTIVE
LAYER DEPTH INTO AN ALREADY FIRM WIND FIELD JUST OFF THE SURFACE.  A
PERIOD OF GOOD 280-285K ISENTROPIC DESCENT WITH 35 TO 40KT WINDS
WITHIN THIS LEVEL WOULD SUGGEST PEAK GUSTS IN EXCESS OF 35 MPH ARE
ATTAINABLE...WITH AN UPTICK TO HEADLINE WORTHY GUST POTENTIAL
CERTAINLY PLAUSIBLE.  WINDOW FOR STRONG CONVERGENCE ALONG THE
FRONTAL SLOPE AND WITH THE PASSAGE OF THE TRAILING WAVE WILL
MAINTAIN A CHANCE FOR SHOWERS INTO MONDAY...PARTICULARLY DURING THE
FIRST HALF OF THE DAY.  PRE-FRONTAL TEMPERATURES PEAK IN THE UPPER
40S-LOWER 50S...STRONGER COLD AIR ADVECTION AWAITING THE BETTER
HEIGHT FALLS TOWARD EVENING.

TUESDAY AND BEYOND...SUBSTANTIAL SOUTHWARD EXPANSION OF THE LOWER
HEIGHT FIELD WILL SPELL ANOTHER EXTENDED STRETCH OF BELOW NORMAL
TEMPERATURES STARTING TUESDAY.  PLACEMENT OF AN ENERGETIC NORTHERN
PACIFIC JET CORE SOUTHEAST AND NEAR/OVER THE GREAT LAKES WILL BRING
THE POTENTIAL FOR A PERIODICALLY ACTIVE PATTERN THROUGH THE UPCOMING
HOLIDAY WEEKEND.  POTENTIAL FOR LIGHT SNOW SHOWERS TUESDAY WITHIN A
MOIST CYCLONIC FLOW...AUGMENTED BY THE MOISTURE FLUX OFF LAKE
MICHIGAN.  WEAK SHORTWAVE WORKING THROUGH THE NORTHWEST FLOW IS
FORECAST TO DEEPEN WITHIN FAVORABLE UPPER JET SUPPORT ON
WEDNESDAY...LONG RANGE MODEL GUIDANCE ALLOWING THIS WAVE TO SHIFT
INTO SOUTHEAST MICHIGAN BY THANKSGIVING.  WHILE SUBJECT TO CHANGE
YET AT THIS TIME SCALE...LATEST TRENDS WOULD BRING THE POTENTIAL FOR
A LIGHT ACCUMULATING SNOWFALL WITH THIS SYSTEM FOR THE HOLIDAY.

&&

.MARINE...

SOUTHWEST WINDS WILL REMAIN STRONG THROUGH THE FIRST HALF OF TODAY.
GUSTS TO GALES OR NEAR GALES WILL EXIST OVER CENTRAL PORTIONS OF
LAKE HURON THROUGH THE MORNING PERIOD.  WINDS WILL EASE SLIGHTLY
THIS AFTERNOON AS THE OVERALL GRADIENT SLACKENS.  A MODEST SOUTHERLY
WIND WILL EXIST TONIGHT AND SUNDAY IN ADVANCE OF STRENGTHENING LOW
PRESSURE.  SOME INCREASE IN SOUTHEAST WINDS WILL OCCUR AS THIS LOW
TRACKS FROM SOUTHERN LAKE MICHIGAN TO THE STRAITS SUNDAY NIGHT.  THE
COMBINATION OF AN INCREASING GRADIENT AND THE RETURN OF COLDER AIR
WILL BRING THE POTENTIAL FOR GALES ACROSS ALL MARINE AREAS BY MONDAY
AFTERNOON AND EVENING.

&&

.AVIATION...ISSUED 1150 PM EST FRI NOV 21 2014

//DISCUSSION...

A WARM FRONT...INITIALLY ELEVATED...WILL LIFT UP INTO LOWER MICHIGAN
LATE TONIGHT AND SATURDAY. THIS WILL ALLOW A WARMER LAYER OF AIR TO
SETTLE IN OVER SUB-FREEZING AIR AT THE SURFACE...POTENTIALLY LEADING
TO FREEZING RAIN AND SLEET AS MOISTURE AND LIFT ARRIVE WITH THE
FRONT. A PERIOD OF FREEZING RAIN OR SLEET WILL BE POSSIBLE BEFORE 14-
16Z BEFORE STRONGER WARM AIR ADVECTION COMMENCES AND PRECIPITATION
CHANGES TO ALL RAIN. THE FRONT WILL ALSO ALLOW CEILINGS TO FALL TO
MVFR...WITH POSSIBLY A DROP TO IFR MID-MORNING SATURDAY.

IN ADDITION...THE LOW-LEVEL JET WILL NOSE INTO THE AREA LATE TONIGHT
AND REMAIN OVERHEAD ON SATURDAY...RESULTING IN A STRONG CORE OF 40-
50 KT WINDS ABOVE 1500 FEET. LOW-LEVEL WIND SHEAR IS EXPECTED AFTER
08Z AT ALL OF THE TAF SITES AND WILL LAST THROUGH THE DAY ON
SATURDAY.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS FALLING BELOW 5000 FEET AFTER 09Z.

* MEDIUM CONFIDENCE WITH AT LEAST A LITTLE FREEZING RAIN AT ONSET OF
  PRECIPITATION BETWEEN 10Z-14Z SATURDAY. HIGH CONFIDENCE
  PRECIPITATION WILL THEN CHANGE TO RAIN DURING THE MID-MORNING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...FREEZING RAIN ADVISORY UNTIL 11 AM EST THIS MORNING FOR MIZ060>063-
     068>070-075-076-082-083.

     FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR MIZ047>049-053>055.

LAKE HURON...GALE WARNING UNTIL 11 AM EST THIS MORNING FOR LHZ362-363-421-462-
     463.

     SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR LHZ441-442.

     SMALL CRAFT ADVISORY UNTIL 11 AM EST THIS MORNING FOR LHZ422.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

SHORT TERM...SF
LONG TERM....MR
MARINE.......MR
AVIATION.....KURIMSKI


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 220830
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
330 AM EST SAT NOV 22 2014

.SHORT TERM...TODAY AND TONIGHT

TEMPERATURES ARE STILL IN THE LOW TO MID 20S EARLY THIS
MORNING...WITH SURFACE DEW PTS IN THE LOWER TEENS.
WITH THIS AMOUNT OF LOW LEVEL DRY AIR IN PLACE...BOUNDARY LAYER WET
BULB TEMPERATURES LOOK TO REMAIN BELOW FREEZING THROUGH THE MORNING
HOURS...PER 00Z NAM. MEANWHILE...WATER VAPOR IMAGERY SHOWS MID LEVEL
WAVE/CIRCULATION LIFTING INTO THE WESTERN GREAT LAKES...WHICH WILL
ALLOW FOR SUBSTANTIAL SURGE OF WARM AND MOIST AIR TO ARRIVE THIS
MORNING...WITH 850 MB DEW POINTS RISING TO BETWEEN 4-5 C. THIS WILL
LEAD TO SOME INSTABILITY...AS SHOWLATER INDEX FALLS TO AROUND ZERO
...WITH GOOD MID LEVEL (700-500 MB) LAPSE RATES IN EXCESS OF 7 C/KM
WORKING THROUGH SOUTHERN LOWER MICHIGAN. DUE TO THE CONVECTIVE
NATURE OF THE ACTIVITY...TOUGH TO GAUGE QPF AREAL COVERAGE...AS
ESPECIALLY THE 00Z GFS IS LIKELY OVERDONE. STILL...BASED ON UPSTREAM
RADAR TRENDS...65-80 PERCENT POPS APPEAR APPROPRIATE...AND HAVE
ELECTED TO EXTEND FREEZING RAIN ADVISORY SOUTH...AS A QUICK GLAZE OF
ICE APPEARS LIKELY WITH THE FROZEN GROUND. SELF-LIMITING
PROCESS/LATENT HEAT RELEASE FROM THE FREEZING RAIN WITH NO COLD AIR
FEED WILL ASSURE TRANSITION TO JUST COLD RAIN AS THE DEEP AND STRONG
SOUTHWEST FLOW OVERSPREADS THE AREA...AND THE WARMER RAIN DROPS TAKE
HOLD. ALTHOUGH ACTIVITY MAY TAPER OFF TO DRIZZLE THIS
AFTERNOON...ANOTHER DEEPER SURGE OF MOISTURE TONIGHT...PW VALUES
INCREASING TO 1 INCH SHOULD ASSURE FURTHER ADDITIONAL LIGHT
RAIN/DRIZZLE...AS MERGING HEIGHT FALLS TAKE PLACE OVER THE CENTRAL
CONUS...BACKING THE FLOW OVER THE MISSISSIPPI RIVER VALLEY. WITH
FORECASTED (SEE EURO) SURFACE DEW PTS OF 40 F COMING OVER COLD/SNOW
COVERED GROUND OVER SOUTHERN LOWER MICHIGAN...ZONES WILL CONTAIN
SOME MENTION OF FOG. THE COLD SNOW COVERED GROUND IS ALSO EXPECTED
TO INHIBIT THE MIXING DEPTHS TODAY...AND THINK WIND GUSTS WILL BE
HARD PRESSED TO EXCEED MUCH PAST 20 KNOTS...DESPITE THE GOOD LOW
LEVEL JET (50 KNOTS).

&&

.LONG TERM...

SUNDAY...COMPACT SOUTHERN STREAM MID LEVEL WAVE NOTED ON WATER VAPOR
THIS MORNING EJECTING EASTWARD ACROSS NORTHERN MEXICO WILL STEADILY
LIFT NORTHEAST AND EVENTUALLY ACROSS THE GREAT LAKES BY SUNDAY
NIGHT.  MOIST LOW LEVEL SOUTHERLY FLOW ALONG THE EASTERN FLANK OF
THE MAIN HEIGHT FALLS WILL MARK CONDITIONS LOCALLY IN ADVANCE OF
THIS SYSTEM ON SUNDAY.  A RENEWED PERIOD OF STRONGER MOIST
ISENTROPIC ASCENT WILL TRANSLATE FROM SOUTH TO NORTH ACROSS THE
REGION DURING THE FIRST HALF OF THE DAY.  THIS PROCESS WILL IMPROVE
THE OVERALL MOISTURE QUALITY /PW AROUND 1 INCH/...IN ADDITION TO
SUPPORTING SOME LIGHT SHOWER DEVELOPMENT DURING THIS TIME.  A BRIEF
LULL IN THE FORCING FOR MIDDAY WILL PROVIDE THE GREATEST WINDOW FOR
A BETTER THERMAL RESPONSE.  A BACKGROUND OF WEAK WARM AIR ADVECTION
WILL COUNTER THE LACK OF MIXING AND INSOLATION POTENTIAL...ALLOWING
HIGHS TO MAKE A RUN TOWARD THE 50 DEGREE MARK.

SUNDAY NIGHT...STRONG MID LEVEL DYNAMICS ANCHORED BY STOUT LEFT EXIT
REGION UPPER JET FORCING...DIVERGENCE AND INCREASING CVA ATTENDANT
TO THE INBOUND WAVE WILL SWEEP ACROSS SE MICHIGAN SUNDAY NIGHT.
THIS FORCING INTO THE EXISTING VERY MOIST AMBIENT ENVIRONMENT WILL
RESULT IN A 6-9 HOUR PERIOD OF WIDESPREAD RAINFALL FOR THE ENTIRE
REGION OVERNIGHT.  QPF AMOUNTS WITHIN THE .5" TO .75" RANGE LOOK
ATTAINABLE GIVEN THE UNDERLYING STRENGTH OF ASCENT...MOISTURE DEPTH
AND OVERALL RESIDENCE TIME.  A FIRM SOUTHEAST GRADIENT WILL CONTAIN
TEMPERATURES IN THE LOWER AND MIDDLE 40S THROUGH THE NIGHT.

MONDAY...00Z NAM REMAINS OUTSIDE THE MODEL CONSENSUS WHICH HOLDS
WITH A MUCH DEEPER SURFACE LOW AS IT TRACKS FROM THE SOUTH END OF
LAKE MICHIGAN THROUGH NORTHERN LAKE HURON DURING THIS TIME.  00Z GFS
SEEMINGLY TOO AGGRESSIVE WITH THE RESPONSE /966 MB CENTER AT 18Z MON
NORTH OF THE STRAITS/...OWING TO MORE PRONOUNCED PHASING OF THE LEAD
PV FEATURE WITH A TRAILING NORTHERN STREAM TROUGH THAT BECOMES
NEGATIVELY TILTED.  THE NET RESULT IS A MORE SIZABLE DIFFERENCE IN
HANDLING THE DETAILS IN THE WAKE OF THE EXITING MAIN MOISTURE PLUME
HEADING INTO MONDAY.  SLIVER OF MILDER PRE-COLD FRONTAL AIR WILL
EXIST MONDAY MORNING...THE TRAILING COLD FRONTAL PASSAGE MOST LIKELY
COMMENCING DURING THE LATTER HALF OF THE DAY.  AT THIS POINT...MAIN
ELEMENT OF CONCERN BECOMES THE WIND POTENTIAL MONDAY AFTERNOON AND
EVENING...AS THE ENSUING ADVECTIVE PROCESS BUILDS THE CONVECTIVE
LAYER DEPTH INTO AN ALREADY FIRM WIND FIELD JUST OFF THE SURFACE.  A
PERIOD OF GOOD 280-285K ISENTROPIC DESCENT WITH 35 TO 40KT WINDS
WITHIN THIS LEVEL WOULD SUGGEST PEAK GUSTS IN EXCESS OF 35 MPH ARE
ATTAINABLE...WITH AN UPTICK TO HEADLINE WORTHY GUST POTENTIAL
CERTAINLY PLAUSIBLE.  WINDOW FOR STRONG CONVERGENCE ALONG THE
FRONTAL SLOPE AND WITH THE PASSAGE OF THE TRAILING WAVE WILL
MAINTAIN A CHANCE FOR SHOWERS INTO MONDAY...PARTICULARLY DURING THE
FIRST HALF OF THE DAY.  PRE-FRONTAL TEMPERATURES PEAK IN THE UPPER
40S-LOWER 50S...STRONGER COLD AIR ADVECTION AWAITING THE BETTER
HEIGHT FALLS TOWARD EVENING.

TUESDAY AND BEYOND...SUBSTANTIAL SOUTHWARD EXPANSION OF THE LOWER
HEIGHT FIELD WILL SPELL ANOTHER EXTENDED STRETCH OF BELOW NORMAL
TEMPERATURES STARTING TUESDAY.  PLACEMENT OF AN ENERGETIC NORTHERN
PACIFIC JET CORE SOUTHEAST AND NEAR/OVER THE GREAT LAKES WILL BRING
THE POTENTIAL FOR A PERIODICALLY ACTIVE PATTERN THROUGH THE UPCOMING
HOLIDAY WEEKEND.  POTENTIAL FOR LIGHT SNOW SHOWERS TUESDAY WITHIN A
MOIST CYCLONIC FLOW...AUGMENTED BY THE MOISTURE FLUX OFF LAKE
MICHIGAN.  WEAK SHORTWAVE WORKING THROUGH THE NORTHWEST FLOW IS
FORECAST TO DEEPEN WITHIN FAVORABLE UPPER JET SUPPORT ON
WEDNESDAY...LONG RANGE MODEL GUIDANCE ALLOWING THIS WAVE TO SHIFT
INTO SOUTHEAST MICHIGAN BY THANKSGIVING.  WHILE SUBJECT TO CHANGE
YET AT THIS TIME SCALE...LATEST TRENDS WOULD BRING THE POTENTIAL FOR
A LIGHT ACCUMULATING SNOWFALL WITH THIS SYSTEM FOR THE HOLIDAY.

&&

.MARINE...

SOUTHWEST WINDS WILL REMAIN STRONG THROUGH THE FIRST HALF OF TODAY.
GUSTS TO GALES OR NEAR GALES WILL EXIST OVER CENTRAL PORTIONS OF
LAKE HURON THROUGH THE MORNING PERIOD.  WINDS WILL EASE SLIGHTLY
THIS AFTERNOON AS THE OVERALL GRADIENT SLACKENS.  A MODEST SOUTHERLY
WIND WILL EXIST TONIGHT AND SUNDAY IN ADVANCE OF STRENGTHENING LOW
PRESSURE.  SOME INCREASE IN SOUTHEAST WINDS WILL OCCUR AS THIS LOW
TRACKS FROM SOUTHERN LAKE MICHIGAN TO THE STRAITS SUNDAY NIGHT.  THE
COMBINATION OF AN INCREASING GRADIENT AND THE RETURN OF COLDER AIR
WILL BRING THE POTENTIAL FOR GALES ACROSS ALL MARINE AREAS BY MONDAY
AFTERNOON AND EVENING.

&&

.AVIATION...ISSUED 1150 PM EST FRI NOV 21 2014

//DISCUSSION...

A WARM FRONT...INITIALLY ELEVATED...WILL LIFT UP INTO LOWER MICHIGAN
LATE TONIGHT AND SATURDAY. THIS WILL ALLOW A WARMER LAYER OF AIR TO
SETTLE IN OVER SUB-FREEZING AIR AT THE SURFACE...POTENTIALLY LEADING
TO FREEZING RAIN AND SLEET AS MOISTURE AND LIFT ARRIVE WITH THE
FRONT. A PERIOD OF FREEZING RAIN OR SLEET WILL BE POSSIBLE BEFORE 14-
16Z BEFORE STRONGER WARM AIR ADVECTION COMMENCES AND PRECIPITATION
CHANGES TO ALL RAIN. THE FRONT WILL ALSO ALLOW CEILINGS TO FALL TO
MVFR...WITH POSSIBLY A DROP TO IFR MID-MORNING SATURDAY.

IN ADDITION...THE LOW-LEVEL JET WILL NOSE INTO THE AREA LATE TONIGHT
AND REMAIN OVERHEAD ON SATURDAY...RESULTING IN A STRONG CORE OF 40-
50 KT WINDS ABOVE 1500 FEET. LOW-LEVEL WIND SHEAR IS EXPECTED AFTER
08Z AT ALL OF THE TAF SITES AND WILL LAST THROUGH THE DAY ON
SATURDAY.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS FALLING BELOW 5000 FEET AFTER 09Z.

* MEDIUM CONFIDENCE WITH AT LEAST A LITTLE FREEZING RAIN AT ONSET OF
  PRECIPITATION BETWEEN 10Z-14Z SATURDAY. HIGH CONFIDENCE
  PRECIPITATION WILL THEN CHANGE TO RAIN DURING THE MID-MORNING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...FREEZING RAIN ADVISORY UNTIL 11 AM EST THIS MORNING FOR MIZ060>063-
     068>070-075-076-082-083.

     FREEZING RAIN ADVISORY UNTIL NOON EST TODAY FOR MIZ047>049-053>055.

LAKE HURON...GALE WARNING UNTIL 11 AM EST THIS MORNING FOR LHZ362-363-421-462-
     463.

     SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR LHZ441-442.

     SMALL CRAFT ADVISORY UNTIL 11 AM EST THIS MORNING FOR LHZ422.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

SHORT TERM...SF
LONG TERM....MR
MARINE.......MR
AVIATION.....KURIMSKI


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 220450
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1150 PM EST FRI NOV 21 2014


.AVIATION...

//DISCUSSION...

A WARM FRONT...INITIALLY ELEVATED...WILL LIFT UP INTO LOWER MICHIGAN
LATE TONIGHT AND SATURDAY. THIS WILL ALLOW A WARMER LAYER OF AIR TO
SETTLE IN OVER SUB-FREEZING AIR AT THE SURFACE...POTENTIALLY LEADING
TO FREEZING RAIN AND SLEET AS MOISTURE AND LIFT ARRIVE WITH THE
FRONT. A PERIOD OF FREEZING RAIN OR SLEET WILL BE POSSIBLE BEFORE 14-
16Z BEFORE STRONGER WARM AIR ADVECTION COMMENCES AND PRECIPITATION
CHANGES TO ALL RAIN. THE FRONT WILL ALSO ALLOW CEILINGS TO FALL TO
MVFR...WITH POSSIBLY A DROP TO IFR MID-MORNING SATURDAY.

IN ADDITION...THE LOW-LEVEL JET WILL NOSE INTO THE AREA LATE TONIGHT
AND REMAIN OVERHEAD ON SATURDAY...RESULTING IN A STRONG CORE OF 40-
50 KT WINDS ABOVE 1500 FEET. LOW-LEVEL WIND SHEAR IS EXPECTED AFTER
08Z AT ALL OF THE TAF SITES AND WILL LAST THROUGH THE DAY ON
SATURDAY.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS FALLING BELOW 5000 FEET AFTER 09Z.

* MEDIUM CONFIDENCE WITH AT LEAST A LITTLE FREEZING RAIN AT ONSET OF
  PRECIPITATION BETWEEN 10Z-14Z SATURDAY. HIGH CONFIDENCE
  PRECIPITATION WILL THEN CHANGE TO RAIN DURING THE MID-MORNING.

&&

.PREV DISCUSSION...ISSUED 328 PM EST FRI NOV 21 2014

SHORT TERM...THROUGH LATE TONIGHT

STRONG HIGH PRESSURE CENTERED OVER THE OHIO VALLEY AND AN UPPER
RIDGE OVER THE WESTERN GREAT LAKES HAVE PROVIDED QUIET CONDITIONS
AND MOSTLY CLEAR SKIES OVER SOUTHEAST MICHIGAN TODAY AS THEY HAVE
WORKED TO QUELL LAKE EFFECT PROCESSES. THE QUIET WEATHER IS EXPECTED
TO CONTINUE THROUGH MOST OF THE NIGHT...ALTHOUGH WE WILL SEE SOME
HIGHER CLOUDS MOVING IN AHEAD OF THE NEXT SYSTEM. TEMPERATURES WILL
DROP PRETTY QUICKLY INTO THE MID TEENS TO NEAR 20 THIS EVENING WITH
CLEAR SKIES AND FRESH SNOW OFF-SETTING 5 TO 10 MPH SOUTHWEST WINDS.
THESE WILL ACTUALLY BE OUR MINS FOR THE NIGHT...AS WARMER AIR BEGINS
TO ADVECT IN OVERNIGHT. MORE DETAILS ON THE WARM FRONT AND WEATHER
EXPECTED ALONG WITH IT (AFTER ABOUT 4 AM) FOLLOW IN THE LONG TERM
DISCUSSION.

LONG TERM...

RETURN FLOW IS UNDERWAY OVER THE EASTERN PLAINS AS HEIGHT FALLS AND
SOUTHERLY FLOW LEADING THE POTENT WAVE DIGGING INTO THE BAJA
OVERSPREAD EASTERN TX, OK, AND KS. THE ASSOCIATED THETA-E RIDGE IS
BEING DRAWN NORTHWARD AND IS NOTED ON VISIBLE SATELLITE IMAGERY AS
WIDESPREAD LOW CLOUDS BENEATH THE DEVELOPING INVERSION SPANNING AN
EVER-INCREASING COVERAGE OF THE MIDWEST. MEANWHILE, A SHORTWAVE
NOTED OVER THE WESTERN HIGH PLAINS THIS AFTERNOON IS IN THE PROCESS
OF LIFTING TO THE NORTHEAST IN ADVANCE OF NORTHERN STREAM SHORTWAVE
TROUGH. THIS WAVE WILL ZIP ACROSS THE GREAT LAKES LATE TONIGHT INTO
EARLY SATURDAY MORNING BRINGING WITH IT A QUICK HIT OF ISENTROPIC
ASCENT/PV ADVECTION AND AND A QUICKLY DEVELOPING LOW-LEVEL JET
RESPONSE. WITH ARCTIC AIR FIRMLY IN PLACE AT THE SURFACE AND WARM
ADVECTION ONGOING ALOFT, CONFIDENCE IN AT LEAST A BROKEN COVERAGE OF
FREEZING SHOWERS 09Z-14Z HAS INCREASED. MODEL CONSENSUS IS THAT WARM
ADVECTIVE SHOWERS WILL NOT BE PARTICULARLY WELL ORGANIZED EXCEPT
THOSE IMMEDIATELY SUPPORTED BY THE DEEPER ASCENT ASSOCIATED WITH THE
PV ANOMALY ITSELF. CURRENT INDICATIONS ARE THAT THIS WILL BE ACROSS
THE FAR NORTH OF THE CWA, WHERE QPF IS A TENTH OF AN INCH OR SO AND
A FREEZING RAIN ADVISORY IS NOW IN EFFECT. WITH ROADS DRYING OUT
TODAY/TONIGHT THINKING IS THAT THERE IS SUFFICIENT POTENTIAL FOR A
BRIEF DISRUPTION TO TRAVEL TO WARRANT ADVISORY ISSUANCE. THERE IS
SOME POTENTIAL FOR A SECONDARY PEAK IN FREEZING RAIN COVERAGE
ASSOCIATED WITH THE THE STRENGTHENING LOW-LEVEL WIND FIELD MAINLY
SOUTH OF DETROIT WHICH WILL WARRANT MONITORING AS THE SCENARIO
UNFOLDS.

THETA-E GRADIENT WILL BECOME INCREASINGLY ZONALLY ORIENTED AS THE
UPPER FLOW FLATTENS OUT SATURDAY INTO SATURDAY NIGHT. PERIODS OF
INCREASED WARM ADVECTION SUPPORT A BLANKET CHC POP. IT IS DIFFICULT
TO ARGUE GOING HIGHER GIVEN THE LACK OF FOCUSED FORCING, BUT CAN
ENVISION A SCENARIO INVOLVING SCATTERED COVERAGE OF SHOWERS INVOF
THE BAROCLINIC ZONE ON SATURDAY, ESPECIALLY AS A WEAKER NORTHERN
STREAM WAVE TRACKS BY DURING THE EVENING. DRIZZLE IS ALSO A
POSSIBILITY ONCE MID-LEVEL MOISTURE IS SCOURED OUT SATURDAY
AFTERNOON. EITHER WAY, SHOULD BE A DREARY AND DAMPISH DAY ALBEIT
WARMER WITH NORMAL TEMPERATURES IN THE 40S.

A POTENT SHEAR MAX WITH ORIGINS IN THE STRONG EAST PAC JET WILL THEN
QUICKLY RACE SOUTHEAST INTO THE TX PANHANDLE BY 12Z SUNDAY CAUSING
THE STRONG PV ANOMALY PRESENTLY DIGGING INTO THE BAJA TO EJECT
NORTHEAST AND ROLL BACK TOWARD THE STRAITS AS SIGNIFICANT LARGE
SCALE HEIGHT FALLS ENVELOP THE CENTRAL UNITED STATES. THE CURVED
UPPER JET THAT DEVELOPS IN RESPONSE TO THE INCREASING HEIGHT
GRADIENT WILL PLACE SOUTHEAST MICHIGAN UNDER VERY STRONG RIGHT
ENTRANCE DYNAMICS & UPPER DIVERGENCE SIMULTANEOUS WITH THE MAXIMUM
IN PV ADVECTION ARRIVING FROM THE SOUTH. THE SURFACE LOW IS PROGGED
TO PASS OVER OR JUST WEST OF THE AREA, CARRYING WITH IT AN
IMPRESSIVELY DEEP LAYER AXIS OF DEFORMATION FLOW. WITH PWATS OF 1.1"
APPROACHING 2 SIGMA TERRITORY FOR LATE NOVEMBER, A WIDESPREAD HALF
TO INCH OF RAIN IN ABOUT 9 HOURS SHOULD NOT BE HARD TO COME BY.
BUMPED POPS UP ANOTHER NOTCH AND RAMPED UP QPF ACCORDINGLY.

LOW PRESSURE TRACKING ACROSS THE GREAT LAKES ON EARLY MONDAY STILL
APPEARS TO START AS MODERATE RAIN...WITH A GRADUAL TRANSITION TO
RAIN/SNOW MIX AND THEN SNOW ON THE BACK SIDE OF THE LOW. NWP STILL
NOT CONVERGENT ON ONE OUTPUT...BUT BELIEVE THIS HIGH POP EVENT WILL
BRING ANOTHER REGIME CHANGE TO BELOW NORMAL THROUGH THE WEEK. MID
LEVEL FLOW REMAINS IN A DOMINANT TROUGH PATTER THROUGH THE EXTENDED
WITH ANY FURTHER IMPULSES ACROSS THE AREA RESULTING IN SNOW SHOWERS.
THIS PATTERN WILL BE FAVORABLE FOR 1-2 CLIPPER SYSTEMS TO DROP A FEW
INCHES OF SNOW TO THE REGION OVER THE NEXT 7 DAYS.

MARINE...

STRONG HIGH PRESSURE WILL SHIFT FROM THE OHIO VALLEY TO THE EAST
COAST TONIGHT...WHILE A LOW PRESSURE SYSTEM DROPS THROUGH NORTHERN
ONTARIO. STRONG SOUTHWEST FLOW WILL DEVELOP OVER THE CENTRAL GREAT
LAKES LATE THIS EVENING THROUGH EARLY SATURDAY AS THE AREA BECOMES
SITUATED BETWEEN THESE TWO FEATURES. ALTHOUGH WARMER AIR WILL BE
STREAMING INTO THE AREA LATE TONIGHT ALONG A WARM FRONT...THE AIR
WILL STILL REMAIN COLDER THAN THE WATER SURFACE...AND ALLOW GUSTS
FROM A STRONG CORE OF WINDS ALOFT TO MIX DOWN TO THE WATER SURFACE.
GALE FORCE WINDS ARE EXPECTED TO DEVELOP OVER MUCH OF LAKE
HURON...INCLUDING OUTER SAGINAW BAY WHERE WINDS WILL GET AN EXTRA
BOOST FROM FUNNELING BETWEEN THE LAND AREAS. WIND SPEEDS WILL
DECREASE ON SATURDAY AS LOW PRESSURE LIFTS INTO QUEBEC AND THE AREA
OF HIGH PRESSURE PUSHES OFF THE EAST COAST.

ANOTHER LOW PRESSURE SYSTEM WILL LIFT ACROSS THE AREA SUNDAY INTO
MONDAY. THIS WILL BRING ANOTHER ROUND OF STRONG SOUTHERLY WINDS TO
THE GREAT LAKES.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...FREEZING RAIN ADVISORY FROM 4 AM TO 9 AM EST SATURDAY FOR
     MIZ047>049-053>055.

LAKE HURON...GALE WARNING UNTIL 11 AM EST SATURDAY FOR LHZ362-363-421-462-463.

     SMALL CRAFT ADVISORY UNTIL 4 PM EST SATURDAY FOR LHZ441-442.

     SMALL CRAFT ADVISORY UNTIL 11 AM EST SATURDAY FOR LHZ422.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....KURIMSKI
SHORT TERM...HLO
LONG TERM....JVC/MM
MARINE.......HLO


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 220450
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1150 PM EST FRI NOV 21 2014


.AVIATION...

//DISCUSSION...

A WARM FRONT...INITIALLY ELEVATED...WILL LIFT UP INTO LOWER MICHIGAN
LATE TONIGHT AND SATURDAY. THIS WILL ALLOW A WARMER LAYER OF AIR TO
SETTLE IN OVER SUB-FREEZING AIR AT THE SURFACE...POTENTIALLY LEADING
TO FREEZING RAIN AND SLEET AS MOISTURE AND LIFT ARRIVE WITH THE
FRONT. A PERIOD OF FREEZING RAIN OR SLEET WILL BE POSSIBLE BEFORE 14-
16Z BEFORE STRONGER WARM AIR ADVECTION COMMENCES AND PRECIPITATION
CHANGES TO ALL RAIN. THE FRONT WILL ALSO ALLOW CEILINGS TO FALL TO
MVFR...WITH POSSIBLY A DROP TO IFR MID-MORNING SATURDAY.

IN ADDITION...THE LOW-LEVEL JET WILL NOSE INTO THE AREA LATE TONIGHT
AND REMAIN OVERHEAD ON SATURDAY...RESULTING IN A STRONG CORE OF 40-
50 KT WINDS ABOVE 1500 FEET. LOW-LEVEL WIND SHEAR IS EXPECTED AFTER
08Z AT ALL OF THE TAF SITES AND WILL LAST THROUGH THE DAY ON
SATURDAY.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS FALLING BELOW 5000 FEET AFTER 09Z.

* MEDIUM CONFIDENCE WITH AT LEAST A LITTLE FREEZING RAIN AT ONSET OF
  PRECIPITATION BETWEEN 10Z-14Z SATURDAY. HIGH CONFIDENCE
  PRECIPITATION WILL THEN CHANGE TO RAIN DURING THE MID-MORNING.

&&

.PREV DISCUSSION...ISSUED 328 PM EST FRI NOV 21 2014

SHORT TERM...THROUGH LATE TONIGHT

STRONG HIGH PRESSURE CENTERED OVER THE OHIO VALLEY AND AN UPPER
RIDGE OVER THE WESTERN GREAT LAKES HAVE PROVIDED QUIET CONDITIONS
AND MOSTLY CLEAR SKIES OVER SOUTHEAST MICHIGAN TODAY AS THEY HAVE
WORKED TO QUELL LAKE EFFECT PROCESSES. THE QUIET WEATHER IS EXPECTED
TO CONTINUE THROUGH MOST OF THE NIGHT...ALTHOUGH WE WILL SEE SOME
HIGHER CLOUDS MOVING IN AHEAD OF THE NEXT SYSTEM. TEMPERATURES WILL
DROP PRETTY QUICKLY INTO THE MID TEENS TO NEAR 20 THIS EVENING WITH
CLEAR SKIES AND FRESH SNOW OFF-SETTING 5 TO 10 MPH SOUTHWEST WINDS.
THESE WILL ACTUALLY BE OUR MINS FOR THE NIGHT...AS WARMER AIR BEGINS
TO ADVECT IN OVERNIGHT. MORE DETAILS ON THE WARM FRONT AND WEATHER
EXPECTED ALONG WITH IT (AFTER ABOUT 4 AM) FOLLOW IN THE LONG TERM
DISCUSSION.

LONG TERM...

RETURN FLOW IS UNDERWAY OVER THE EASTERN PLAINS AS HEIGHT FALLS AND
SOUTHERLY FLOW LEADING THE POTENT WAVE DIGGING INTO THE BAJA
OVERSPREAD EASTERN TX, OK, AND KS. THE ASSOCIATED THETA-E RIDGE IS
BEING DRAWN NORTHWARD AND IS NOTED ON VISIBLE SATELLITE IMAGERY AS
WIDESPREAD LOW CLOUDS BENEATH THE DEVELOPING INVERSION SPANNING AN
EVER-INCREASING COVERAGE OF THE MIDWEST. MEANWHILE, A SHORTWAVE
NOTED OVER THE WESTERN HIGH PLAINS THIS AFTERNOON IS IN THE PROCESS
OF LIFTING TO THE NORTHEAST IN ADVANCE OF NORTHERN STREAM SHORTWAVE
TROUGH. THIS WAVE WILL ZIP ACROSS THE GREAT LAKES LATE TONIGHT INTO
EARLY SATURDAY MORNING BRINGING WITH IT A QUICK HIT OF ISENTROPIC
ASCENT/PV ADVECTION AND AND A QUICKLY DEVELOPING LOW-LEVEL JET
RESPONSE. WITH ARCTIC AIR FIRMLY IN PLACE AT THE SURFACE AND WARM
ADVECTION ONGOING ALOFT, CONFIDENCE IN AT LEAST A BROKEN COVERAGE OF
FREEZING SHOWERS 09Z-14Z HAS INCREASED. MODEL CONSENSUS IS THAT WARM
ADVECTIVE SHOWERS WILL NOT BE PARTICULARLY WELL ORGANIZED EXCEPT
THOSE IMMEDIATELY SUPPORTED BY THE DEEPER ASCENT ASSOCIATED WITH THE
PV ANOMALY ITSELF. CURRENT INDICATIONS ARE THAT THIS WILL BE ACROSS
THE FAR NORTH OF THE CWA, WHERE QPF IS A TENTH OF AN INCH OR SO AND
A FREEZING RAIN ADVISORY IS NOW IN EFFECT. WITH ROADS DRYING OUT
TODAY/TONIGHT THINKING IS THAT THERE IS SUFFICIENT POTENTIAL FOR A
BRIEF DISRUPTION TO TRAVEL TO WARRANT ADVISORY ISSUANCE. THERE IS
SOME POTENTIAL FOR A SECONDARY PEAK IN FREEZING RAIN COVERAGE
ASSOCIATED WITH THE THE STRENGTHENING LOW-LEVEL WIND FIELD MAINLY
SOUTH OF DETROIT WHICH WILL WARRANT MONITORING AS THE SCENARIO
UNFOLDS.

THETA-E GRADIENT WILL BECOME INCREASINGLY ZONALLY ORIENTED AS THE
UPPER FLOW FLATTENS OUT SATURDAY INTO SATURDAY NIGHT. PERIODS OF
INCREASED WARM ADVECTION SUPPORT A BLANKET CHC POP. IT IS DIFFICULT
TO ARGUE GOING HIGHER GIVEN THE LACK OF FOCUSED FORCING, BUT CAN
ENVISION A SCENARIO INVOLVING SCATTERED COVERAGE OF SHOWERS INVOF
THE BAROCLINIC ZONE ON SATURDAY, ESPECIALLY AS A WEAKER NORTHERN
STREAM WAVE TRACKS BY DURING THE EVENING. DRIZZLE IS ALSO A
POSSIBILITY ONCE MID-LEVEL MOISTURE IS SCOURED OUT SATURDAY
AFTERNOON. EITHER WAY, SHOULD BE A DREARY AND DAMPISH DAY ALBEIT
WARMER WITH NORMAL TEMPERATURES IN THE 40S.

A POTENT SHEAR MAX WITH ORIGINS IN THE STRONG EAST PAC JET WILL THEN
QUICKLY RACE SOUTHEAST INTO THE TX PANHANDLE BY 12Z SUNDAY CAUSING
THE STRONG PV ANOMALY PRESENTLY DIGGING INTO THE BAJA TO EJECT
NORTHEAST AND ROLL BACK TOWARD THE STRAITS AS SIGNIFICANT LARGE
SCALE HEIGHT FALLS ENVELOP THE CENTRAL UNITED STATES. THE CURVED
UPPER JET THAT DEVELOPS IN RESPONSE TO THE INCREASING HEIGHT
GRADIENT WILL PLACE SOUTHEAST MICHIGAN UNDER VERY STRONG RIGHT
ENTRANCE DYNAMICS & UPPER DIVERGENCE SIMULTANEOUS WITH THE MAXIMUM
IN PV ADVECTION ARRIVING FROM THE SOUTH. THE SURFACE LOW IS PROGGED
TO PASS OVER OR JUST WEST OF THE AREA, CARRYING WITH IT AN
IMPRESSIVELY DEEP LAYER AXIS OF DEFORMATION FLOW. WITH PWATS OF 1.1"
APPROACHING 2 SIGMA TERRITORY FOR LATE NOVEMBER, A WIDESPREAD HALF
TO INCH OF RAIN IN ABOUT 9 HOURS SHOULD NOT BE HARD TO COME BY.
BUMPED POPS UP ANOTHER NOTCH AND RAMPED UP QPF ACCORDINGLY.

LOW PRESSURE TRACKING ACROSS THE GREAT LAKES ON EARLY MONDAY STILL
APPEARS TO START AS MODERATE RAIN...WITH A GRADUAL TRANSITION TO
RAIN/SNOW MIX AND THEN SNOW ON THE BACK SIDE OF THE LOW. NWP STILL
NOT CONVERGENT ON ONE OUTPUT...BUT BELIEVE THIS HIGH POP EVENT WILL
BRING ANOTHER REGIME CHANGE TO BELOW NORMAL THROUGH THE WEEK. MID
LEVEL FLOW REMAINS IN A DOMINANT TROUGH PATTER THROUGH THE EXTENDED
WITH ANY FURTHER IMPULSES ACROSS THE AREA RESULTING IN SNOW SHOWERS.
THIS PATTERN WILL BE FAVORABLE FOR 1-2 CLIPPER SYSTEMS TO DROP A FEW
INCHES OF SNOW TO THE REGION OVER THE NEXT 7 DAYS.

MARINE...

STRONG HIGH PRESSURE WILL SHIFT FROM THE OHIO VALLEY TO THE EAST
COAST TONIGHT...WHILE A LOW PRESSURE SYSTEM DROPS THROUGH NORTHERN
ONTARIO. STRONG SOUTHWEST FLOW WILL DEVELOP OVER THE CENTRAL GREAT
LAKES LATE THIS EVENING THROUGH EARLY SATURDAY AS THE AREA BECOMES
SITUATED BETWEEN THESE TWO FEATURES. ALTHOUGH WARMER AIR WILL BE
STREAMING INTO THE AREA LATE TONIGHT ALONG A WARM FRONT...THE AIR
WILL STILL REMAIN COLDER THAN THE WATER SURFACE...AND ALLOW GUSTS
FROM A STRONG CORE OF WINDS ALOFT TO MIX DOWN TO THE WATER SURFACE.
GALE FORCE WINDS ARE EXPECTED TO DEVELOP OVER MUCH OF LAKE
HURON...INCLUDING OUTER SAGINAW BAY WHERE WINDS WILL GET AN EXTRA
BOOST FROM FUNNELING BETWEEN THE LAND AREAS. WIND SPEEDS WILL
DECREASE ON SATURDAY AS LOW PRESSURE LIFTS INTO QUEBEC AND THE AREA
OF HIGH PRESSURE PUSHES OFF THE EAST COAST.

ANOTHER LOW PRESSURE SYSTEM WILL LIFT ACROSS THE AREA SUNDAY INTO
MONDAY. THIS WILL BRING ANOTHER ROUND OF STRONG SOUTHERLY WINDS TO
THE GREAT LAKES.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...FREEZING RAIN ADVISORY FROM 4 AM TO 9 AM EST SATURDAY FOR
     MIZ047>049-053>055.

LAKE HURON...GALE WARNING UNTIL 11 AM EST SATURDAY FOR LHZ362-363-421-462-463.

     SMALL CRAFT ADVISORY UNTIL 4 PM EST SATURDAY FOR LHZ441-442.

     SMALL CRAFT ADVISORY UNTIL 11 AM EST SATURDAY FOR LHZ422.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....KURIMSKI
SHORT TERM...HLO
LONG TERM....JVC/MM
MARINE.......HLO


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 212315
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
615 PM EST FRI NOV 21 2014


.AVIATION...

//DISCUSSION...

HIGH PRESSURE WILL SHIFT TOWARDS THE EAST COAST TONIGHT...ALLOWING
CLOUDS TO SPREAD INTO THE AREA FROM THE WEST. A WARM
FRONT...INITIALLY ELEVATED...WILL THEN LIFT UP INTO LOWER MICHIGAN
LATE TONIGHT AND SATURDAY. THIS WILL ALLOW A WARMER LAYER OF AIR TO
SETTLE IN OVER SUB-FREEZING AIR AT THE SURFACE...POTENTIALLY LEADING
TO FREEZING RAIN AND SLEET AS MOISTURE AND LIFT ARRIVE WITH THE
FRONT. A PERIOD OF FREEZING RAIN OR SLEET WILL BE POSSIBLE BEFORE 14-
16Z BEFORE STRONGER WARM AIR ADVECTION COMMENCES AND PRECIPITATION
CHANGES TO ALL RAIN. THE FRONT WILL ALSO ALLOW CEILINGS TO FALL TO
MVFR...WITH POSSIBLY A DROP TO IFR MID-MORNING SATURDAY.

IN ADDITION...THE LOW-LEVEL JET WILL NOSE INTO THE AREA LATE TONIGHT
AND REMAIN OVERHEAD ON SATURDAY...RESULTING IN A STRONG CORE OF 40-
50 KT WINDS ABOVE 1500 FEET. LOW-LEVEL WIND SHEAR IS EXPECTED AFTER
08Z AT ALL OF THE TAF SITES.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS FALLING BELOW 5000 FEET AFTER 09Z
  SATURDAY.

* MEDIUM CONFIDENCE WITH AT LEAST A LITTLE FREEZING RAIN AT ONSET OF
  PRECIPITATION BETWEEN 08Z-13Z SATURDAY. HIGH CONFIDENCE
  PRECIPITATION WILL THEN CHANGE TO RAIN DURING THE MID-MORNING.

&&

.PREV DISCUSSION...ISSUED 328 PM EST FRI NOV 21 2014

SHORT TERM...THROUGH LATE TONIGHT

STRONG HIGH PRESSURE CENTERED OVER THE OHIO VALLEY AND AN UPPER
RIDGE OVER THE WESTERN GREAT LAKES HAVE PROVIDED QUIET CONDITIONS
AND MOSTLY CLEAR SKIES OVER SOUTHEAST MICHIGAN TODAY AS THEY HAVE
WORKED TO QUELL LAKE EFFECT PROCESSES. THE QUIET WEATHER IS EXPECTED
TO CONTINUE THROUGH MOST OF THE NIGHT...ALTHOUGH WE WILL SEE SOME
HIGHER CLOUDS MOVING IN AHEAD OF THE NEXT SYSTEM. TEMPERATURES WILL
DROP PRETTY QUICKLY INTO THE MID TEENS TO NEAR 20 THIS EVENING WITH
CLEAR SKIES AND FRESH SNOW OFF-SETTING 5 TO 10 MPH SOUTHWEST WINDS.
THESE WILL ACTUALLY BE OUR MINS FOR THE NIGHT...AS WARMER AIR BEGINS
TO ADVECT IN OVERNIGHT. MORE DETAILS ON THE WARM FRONT AND WEATHER
EXPECTED ALONG WITH IT (AFTER ABOUT 4 AM) FOLLOW IN THE LONG TERM
DISCUSSION.

LONG TERM...

RETURN FLOW IS UNDERWAY OVER THE EASTERN PLAINS AS HEIGHT FALLS AND
SOUTHERLY FLOW LEADING THE POTENT WAVE DIGGING INTO THE BAJA
OVERSPREAD EASTERN TX, OK, AND KS. THE ASSOCIATED THETA-E RIDGE IS
BEING DRAWN NORTHWARD AND IS NOTED ON VISIBLE SATELLITE IMAGERY AS
WIDESPREAD LOW CLOUDS BENEATH THE DEVELOPING INVERSION SPANNING AN
EVER-INCREASING COVERAGE OF THE MIDWEST. MEANWHILE, A SHORTWAVE
NOTED OVER THE WESTERN HIGH PLAINS THIS AFTERNOON IS IN THE PROCESS
OF LIFTING TO THE NORTHEAST IN ADVANCE OF NORTHERN STREAM SHORTWAVE
TROUGH. THIS WAVE WILL ZIP ACROSS THE GREAT LAKES LATE TONIGHT INTO
EARLY SATURDAY MORNING BRINGING WITH IT A QUICK HIT OF ISENTROPIC
ASCENT/PV ADVECTION AND AND A QUICKLY DEVELOPING LOW-LEVEL JET
RESPONSE. WITH ARCTIC AIR FIRMLY IN PLACE AT THE SURFACE AND WARM
ADVECTION ONGOING ALOFT, CONFIDENCE IN AT LEAST A BROKEN COVERAGE OF
FREEZING SHOWERS 09Z-14Z HAS INCREASED. MODEL CONSENSUS IS THAT WARM
ADVECTIVE SHOWERS WILL NOT BE PARTICULARLY WELL ORGANIZED EXCEPT
THOSE IMMEDIATELY SUPPORTED BY THE DEEPER ASCENT ASSOCIATED WITH THE
PV ANOMALY ITSELF. CURRENT INDICATIONS ARE THAT THIS WILL BE ACROSS
THE FAR NORTH OF THE CWA, WHERE QPF IS A TENTH OF AN INCH OR SO AND
A FREEZING RAIN ADVISORY IS NOW IN EFFECT. WITH ROADS DRYING OUT
TODAY/TONIGHT THINKING IS THAT THERE IS SUFFICIENT POTENTIAL FOR A
BRIEF DISRUPTION TO TRAVEL TO WARRANT ADVISORY ISSUANCE. THERE IS
SOME POTENTIAL FOR A SECONDARY PEAK IN FREEZING RAIN COVERAGE
ASSOCIATED WITH THE THE STRENGTHENING LOW-LEVEL WIND FIELD MAINLY
SOUTH OF DETROIT WHICH WILL WARRANT MONITORING AS THE SCENARIO
UNFOLDS.

THETA-E GRADIENT WILL BECOME INCREASINGLY ZONALLY ORIENTED AS THE
UPPER FLOW FLATTENS OUT SATURDAY INTO SATURDAY NIGHT. PERIODS OF
INCREASED WARM ADVECTION SUPPORT A BLANKET CHC POP. IT IS DIFFICULT
TO ARGUE GOING HIGHER GIVEN THE LACK OF FOCUSED FORCING, BUT CAN
ENVISION A SCENARIO INVOLVING SCATTERED COVERAGE OF SHOWERS INVOF
THE BAROCLINIC ZONE ON SATURDAY, ESPECIALLY AS A WEAKER NORTHERN
STREAM WAVE TRACKS BY DURING THE EVENING. DRIZZLE IS ALSO A
POSSIBILITY ONCE MID-LEVEL MOISTURE IS SCOURED OUT SATURDAY
AFTERNOON. EITHER WAY, SHOULD BE A DREARY AND DAMPISH DAY ALBEIT
WARMER WITH NORMAL TEMPERATURES IN THE 40S.

A POTENT SHEAR MAX WITH ORIGINS IN THE STRONG EAST PAC JET WILL THEN
QUICKLY RACE SOUTHEAST INTO THE TX PANHANDLE BY 12Z SUNDAY CAUSING
THE STRONG PV ANOMALY PRESENTLY DIGGING INTO THE BAJA TO EJECT
NORTHEAST AND ROLL BACK TOWARD THE STRAITS AS SIGNIFICANT LARGE
SCALE HEIGHT FALLS ENVELOP THE CENTRAL UNITED STATES. THE CURVED
UPPER JET THAT DEVELOPS IN RESPONSE TO THE INCREASING HEIGHT
GRADIENT WILL PLACE SOUTHEAST MICHIGAN UNDER VERY STRONG RIGHT
ENTRANCE DYNAMICS & UPPER DIVERGENCE SIMULTANEOUS WITH THE MAXIMUM
IN PV ADVECTION ARRIVING FROM THE SOUTH. THE SURFACE LOW IS PROGGED
TO PASS OVER OR JUST WEST OF THE AREA, CARRYING WITH IT AN
IMPRESSIVELY DEEP LAYER AXIS OF DEFORMATION FLOW. WITH PWATS OF 1.1"
APPROACHING 2 SIGMA TERRITORY FOR LATE NOVEMBER, A WIDESPREAD HALF
TO INCH OF RAIN IN ABOUT 9 HOURS SHOULD NOT BE HARD TO COME BY.
BUMPED POPS UP ANOTHER NOTCH AND RAMPED UP QPF ACCORDINGLY.

LOW PRESSURE TRACKING ACROSS THE GREAT LAKES ON EARLY MONDAY STILL
APPEARS TO START AS MODERATE RAIN...WITH A GRADUAL TRANSITION TO
RAIN/SNOW MIX AND THEN SNOW ON THE BACK SIDE OF THE LOW. NWP STILL
NOT CONVERGENT ON ONE OUTPUT...BUT BELIEVE THIS HIGH POP EVENT WILL
BRING ANOTHER REGIME CHANGE TO BELOW NORMAL THROUGH THE WEEK. MID
LEVEL FLOW REMAINS IN A DOMINANT TROUGH PATTER THROUGH THE EXTENDED
WITH ANY FURTHER IMPULSES ACROSS THE AREA RESULTING IN SNOW SHOWERS.
THIS PATTERN WILL BE FAVORABLE FOR 1-2 CLIPPER SYSTEMS TO DROP A FEW
INCHES OF SNOW TO THE REGION OVER THE NEXT 7 DAYS.

MARINE...

STRONG HIGH PRESSURE WILL SHIFT FROM THE OHIO VALLEY TO THE EAST
COAST TONIGHT...WHILE A LOW PRESSURE SYSTEM DROPS THROUGH NORTHERN
ONTARIO. STRONG SOUTHWEST FLOW WILL DEVELOP OVER THE CENTRAL GREAT
LAKES LATE THIS EVENING THROUGH EARLY SATURDAY AS THE AREA BECOMES
SITUATED BETWEEN THESE TWO FEATURES. ALTHOUGH WARMER AIR WILL BE
STREAMING INTO THE AREA LATE TONIGHT ALONG A WARM FRONT...THE AIR
WILL STILL REMAIN COLDER THAN THE WATER SURFACE...AND ALLOW GUSTS
FROM A STRONG CORE OF WINDS ALOFT TO MIX DOWN TO THE WATER SURFACE.
GALE FORCE WINDS ARE EXPECTED TO DEVELOP OVER MUCH OF LAKE
HURON...INCLUDING OUTER SAGINAW BAY WHERE WINDS WILL GET AN EXTRA
BOOST FROM FUNNELING BETWEEN THE LAND AREAS. WIND SPEEDS WILL
DECREASE ON SATURDAY AS LOW PRESSURE LIFTS INTO QUEBEC AND THE AREA
OF HIGH PRESSURE PUSHES OFF THE EAST COAST.

ANOTHER LOW PRESSURE SYSTEM WILL LIFT ACROSS THE AREA SUNDAY INTO
MONDAY. THIS WILL BRING ANOTHER ROUND OF STRONG SOUTHERLY WINDS TO
THE GREAT LAKES.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...FREEZING RAIN ADVISORY FROM 4 AM TO 9 AM EST SATURDAY FOR
     MIZ047>049-053>055.

LAKE HURON...GALE WARNING UNTIL 11 AM EST SATURDAY FOR LHZ362-363-421-462-463.

     SMALL CRAFT ADVISORY UNTIL 4 PM EST SATURDAY FOR LHZ441-442.

     SMALL CRAFT ADVISORY UNTIL 11 AM EST SATURDAY FOR LHZ422.

     SMALL CRAFT ADVISORY UNTIL 9 PM EST THIS EVENING FOR LHZ421.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....KURIMSKI
SHORT TERM...HLO
LONG TERM....JVC/MM
MARINE.......HLO


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 212028
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
328 PM EST FRI NOV 21 2014

.SHORT TERM...THROUGH LATE TONIGHT

STRONG HIGH PRESSURE CENTERED OVER THE OHIO VALLEY AND AN UPPER
RIDGE OVER THE WESTERN GREAT LAKES HAVE PROVIDED QUIET CONDITIONS
AND MOSTLY CLEAR SKIES OVER SOUTHEAST MICHIGAN TODAY AS THEY HAVE
WORKED TO QUELL LAKE EFFECT PROCESSES. THE QUIET WEATHER IS EXPECTED
TO CONTINUE THROUGH MOST OF THE NIGHT...ALTHOUGH WE WILL SEE SOME
HIGHER CLOUDS MOVING IN AHEAD OF THE NEXT SYSTEM. TEMPERATURES WILL
DROP PRETTY QUICKLY INTO THE MID TEENS TO NEAR 20 THIS EVENING WITH
CLEAR SKIES AND FRESH SNOW OFF-SETTING 5 TO 10 MPH SOUTHWEST WINDS.
THESE WILL ACTUALLY BE OUR MINS FOR THE NIGHT...AS WARMER AIR BEGINS
TO ADVECT IN OVERNIGHT. MORE DETAILS ON THE WARM FRONT AND WEATHER
EXPECTED ALONG WITH IT (AFTER ABOUT 4 AM) FOLLOW IN THE LONG TERM
DISCUSSION.

&&

.LONG TERM...

RETURN FLOW IS UNDERWAY OVER THE EASTERN PLAINS AS HEIGHT FALLS AND
SOUTHERLY FLOW LEADING THE POTENT WAVE DIGGING INTO THE BAJA
OVERSPREAD EASTERN TX, OK, AND KS. THE ASSOCIATED THETA-E RIDGE IS
BEING DRAWN NORTHWARD AND IS NOTED ON VISIBLE SATELLITE IMAGERY AS
WIDESPREAD LOW CLOUDS BENEATH THE DEVELOPING INVERSION SPANNING AN
EVER-INCREASING COVERAGE OF THE MIDWEST. MEANWHILE, A SHORTWAVE
NOTED OVER THE WESTERN HIGH PLAINS THIS AFTERNOON IS IN THE PROCESS
OF LIFTING TO THE NORTHEAST IN ADVANCE OF NORTHERN STREAM SHORTWAVE
TROUGH. THIS WAVE WILL ZIP ACROSS THE GREAT LAKES LATE TONIGHT INTO
EARLY SATURDAY MORNING BRINGING WITH IT A QUICK HIT OF ISENTROPIC
ASCENT/PV ADVECTION AND AND A QUICKLY DEVELOPING LOW-LEVEL JET
RESPONSE. WITH ARCTIC AIR FIRMLY IN PLACE AT THE SURFACE AND WARM
ADVECTION ONGOING ALOFT, CONFIDENCE IN AT LEAST A BROKEN COVERAGE OF
FREEZING SHOWERS 09Z-14Z HAS INCREASED. MODEL CONSENSUS IS THAT WARM
ADVECTIVE SHOWERS WILL NOT BE PARTICULARLY WELL ORGANIZED EXCEPT
THOSE IMMEDIATELY SUPPORTED BY THE DEEPER ASCENT ASSOCIATED WITH THE
PV ANOMALY ITSELF. CURRENT INDICATIONS ARE THAT THIS WILL BE ACROSS
THE FAR NORTH OF THE CWA, WHERE QPF IS A TENTH OF AN INCH OR SO AND
A FREEZING RAIN ADVISORY IS NOW IN EFFECT. WITH ROADS DRYING OUT
TODAY/TONIGHT THINKING IS THAT THERE IS SUFFICIENT POTENTIAL FOR A
BRIEF DISRUPTION TO TRAVEL TO WARRANT ADVISORY ISSUANCE. THERE IS
SOME POTENTIAL FOR A SECONDARY PEAK IN FREEZING RAIN COVERAGE
ASSOCIATED WITH THE THE STRENGTHENING LOW-LEVEL WIND FIELD MAINLY
SOUTH OF DETROIT WHICH WILL WARRANT MONITORING AS THE SCENARIO
UNFOLDS.

THETA-E GRADIENT WILL BECOME INCREASINGLY ZONALLY ORIENTED AS THE
UPPER FLOW FLATTENS OUT SATURDAY INTO SATURDAY NIGHT. PERIODS OF
INCREASED WARM ADVECTION SUPPORT A BLANKET CHC POP. IT IS DIFFICULT
TO ARGUE GOING HIGHER GIVEN THE LACK OF FOCUSED FORCING, BUT CAN
ENVISION A SCENARIO INVOLVING SCATTERED COVERAGE OF SHOWERS INVOF
THE BAROCLINIC ZONE ON SATURDAY, ESPECIALLY AS A WEAKER NORTHERN
STREAM WAVE TRACKS BY DURING THE EVENING. DRIZZLE IS ALSO A
POSSIBILITY ONCE MID-LEVEL MOISTURE IS SCOURED OUT SATURDAY
AFTERNOON. EITHER WAY, SHOULD BE A DREARY AND DAMPISH DAY ALBEIT
WARMER WITH NORMAL TEMPERATURES IN THE 40S.

A POTENT SHEAR MAX WITH ORIGINS IN THE STRONG EAST PAC JET WILL THEN
QUICKLY RACE SOUTHEAST INTO THE TX PANHANDLE BY 12Z SUNDAY CAUSING
THE STRONG PV ANOMALY PRESENTLY DIGGING INTO THE BAJA TO EJECT
NORTHEAST AND ROLL BACK TOWARD THE STRAITS AS SIGNIFICANT LARGE
SCALE HEIGHT FALLS ENVELOP THE CENTRAL UNITED STATES. THE CURVED
UPPER JET THAT DEVELOPS IN RESPONSE TO THE INCREASING HEIGHT
GRADIENT WILL PLACE SOUTHEAST MICHIGAN UNDER VERY STRONG RIGHT
ENTRANCE DYNAMICS & UPPER DIVERGENCE SIMULTANEOUS WITH THE MAXIMUM
IN PV ADVECTION ARRIVING FROM THE SOUTH. THE SURFACE LOW IS PROGGED
TO PASS OVER OR JUST WEST OF THE AREA, CARRYING WITH IT AN
IMPRESSIVELY DEEP LAYER AXIS OF DEFORMATION FLOW. WITH PWATS OF 1.1"
APPROACHING 2 SIGMA TERRITORY FOR LATE NOVEMBER, A WIDESPREAD HALF
TO INCH OF RAIN IN ABOUT 9 HOURS SHOULD NOT BE HARD TO COME BY.
BUMPED POPS UP ANOTHER NOTCH AND RAMPED UP QPF ACCORDINGLY.

LOW PRESSURE TRACKING ACROSS THE GREAT LAKES ON EARLY MONDAY STILL
APPEARS TO START AS MODERATE RAIN...WITH A GRADUAL TRANSITION TO
RAIN/SNOW MIX AND THEN SNOW ON THE BACK SIDE OF THE LOW. NWP STILL
NOT CONVERGENT ON ONE OUTPUT...BUT BELIEVE THIS HIGH POP EVENT WILL
BRING ANOTHER REGIME CHANGE TO BELOW NORMAL THROUGH THE WEEK. MID
LEVEL FLOW REMAINS IN A DOMINANT TROUGH PATTER THROUGH THE EXTENDED
WITH ANY FURTHER IMPULSES ACROSS THE AREA RESULTING IN SNOW SHOWERS.
THIS PATTERN WILL BE FAVORABLE FOR 1-2 CLIPPER SYSTEMS TO DROP A FEW
INCHES OF SNOW TO THE REGION OVER THE NEXT 7 DAYS.

&&

.MARINE...

STRONG HIGH PRESSURE WILL SHIFT FROM THE OHIO VALLEY TO THE EAST
COAST TONIGHT...WHILE A LOW PRESSURE SYSTEM DROPS THROUGH NORTHERN
ONTARIO. STRONG SOUTHWEST FLOW WILL DEVELOP OVER THE CENTRAL GREAT
LAKES LATE THIS EVENING THROUGH EARLY SATURDAY AS THE AREA BECOMES
SITUATED BETWEEN THESE TWO FEATURES. ALTHOUGH WARMER AIR WILL BE
STREAMING INTO THE AREA LATE TONIGHT ALONG A WARM FRONT...THE AIR
WILL STILL REMAIN COLDER THAN THE WATER SURFACE...AND ALLOW GUSTS
FROM A STRONG CORE OF WINDS ALOFT TO MIX DOWN TO THE WATER SURFACE.
GALE FORCE WINDS ARE EXPECTED TO DEVELOP OVER MUCH OF LAKE
HURON...INCLUDING OUTER SAGINAW BAY WHERE WINDS WILL GET AN EXTRA
BOOST FROM FUNNELING BETWEEN THE LAND AREAS. WIND SPEEDS WILL
DECREASE ON SATURDAY AS LOW PRESSURE LIFTS INTO QUEBEC AND THE AREA
OF HIGH PRESSURE PUSHES OFF THE EAST COAST.

ANOTHER LOW PRESSURE SYSTEM WILL LIFT ACROSS THE AREA SUNDAY INTO
MONDAY. THIS WILL BRING ANOTHER ROUND OF STRONG SOUTHERLY WINDS TO
THE GREAT LAKES.

&&

.AVIATION...ISSUED 1231 PM EST FRI NOV 21 2014

//DISCUSSION...

HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL KEEP MAINTAIN VFR
CONDITIONS TODAY...BUT THERE WILL BE A SOME CU THAT DEVELOPS BETWEEN
2500 AND 3500 FEET. THE HIGH WILL SHIFT TOWARDS THE EAST COAST
TONIGHT...ALLOWING CLOUDS TO SPREAD INTO THE AREA. A WARM
FRONT...INITIALLY ELEVATED...WILL THEN LIFT UP INTO LOWER MICHIGAN
LATE TONIGHT AND SATURDAY. THIS WILL ALLOW A WARMER LAYER OF AIR TO
SETTLE IN OVER SUB-FREEZING AIR AT THE SURFACE...POTENTIALLY LEADING
TO FREEZING RAIN AND SLEET AS MOISTURE AND LIFT ARRIVE WITH THE
FRONT. A PERIOD OF FREEZING RAIN OR SLEET WILL BE POSSIBLE BEFORE 14-
16Z BEFORE STRONGER WARM AIR ADVECTION COMMENCES AND PRECIPITATION
CHANGES TO ALL RAIN. THE FRONT WILL ALSO ALLOW CEILINGS TO FALL TO
MVFR...WITH POSSIBLY A DROP TO IFR MID-MORNING SATURDAY.

IN ADDITION...THE LOW-LEVEL JET WILL NOSE INTO THE AREA LATE TONIGHT
AND REMAIN OVERHEAD TOMORROW RESULTING IN A STRONG CORE OF 40-50 KT
WINDS ABOVE 1500 FEET. LOW-LEVEL WIND SHEAR WAS THEREFORE ADDED TO
THE TAFS AFTER 08Z.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS FALLING BELOW 5000 FEET AFTER 09Z
  SATURDAY.

* MEDIUM CONFIDENCE WITH AT LEAST A LITTLE FREEZING RAIN AT ONSET OF
  PRECIPITATION BETWEEN 08Z-13Z SATURDAY. HIGH CONFIDENCE
  PRECIPITATION WILL THEN CHANGE TO RAIN DURING THE MID-MORNING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...FREEZING RAIN ADVISORY FROM 4 AM TO 9 AM EST SATURDAY FOR
     MIZ047>049-053>055.

LAKE HURON...GALE WARNING FROM 9 PM THIS EVENING TO 11 AM EST SATURDAY FOR
     LHZ362-363-421-462-463.

     SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 11 AM EST SATURDAY
     FOR LHZ441-442.

     SMALL CRAFT ADVISORY UNTIL 11 AM EST SATURDAY FOR LHZ422.

     SMALL CRAFT ADVISORY UNTIL 9 PM EST THIS EVENING FOR LHZ421.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

SHORT TERM...HLO
LONG TERM....JVC/MM
MARINE.......HLO
AVIATION.....HLO


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 211731
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1231 PM EST FRI NOV 21 2014


.AVIATION...

//DISCUSSION...

HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL KEEP MAINTAIN VFR
CONDITIONS TODAY...BUT THERE WILL BE A SOME CU THAT DEVELOPS BETWEEN
2500 AND 3500 FEET. THE HIGH WILL SHIFT TOWARDS THE EAST COAST
TONIGHT...ALLOWING CLOUDS TO SPREAD INTO THE AREA. A WARM
FRONT...INITIALLY ELEVATED...WILL THEN LIFT UP INTO LOWER MICHIGAN
LATE TONIGHT AND SATURDAY. THIS WILL ALLOW A WARMER LAYER OF AIR TO
SETTLE IN OVER SUB-FREEZING AIR AT THE SURFACE...POTENTIALLY LEADING
TO FREEZING RAIN AND SLEET AS MOISTURE AND LIFT ARRIVE WITH THE
FRONT. A PERIOD OF FREEZING RAIN OR SLEET WILL BE POSSIBLE BEFORE 14-
16Z BEFORE STRONGER WARM AIR ADVECTION COMMENCES AND PRECIPITATION
CHANGES TO ALL RAIN. THE FRONT WILL ALSO ALLOW CEILINGS TO FALL TO
MVFR...WITH POSSIBLY A DROP TO IFR MID-MORNING SATURDAY.

IN ADDITION...THE LOW-LEVEL JET WILL NOSE INTO THE AREA LATE TONIGHT
AND REMAIN OVERHEAD TOMORROW RESULTING IN A STRONG CORE OF 40-50 KT
WINDS ABOVE 1500 FEET. LOW-LEVEL WIND SHEAR WAS THEREFORE ADDED TO
THE TAFS AFTER 08Z.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS FALLING BELOW 5000 FEET AFTER 09Z
  SATURDAY.

* MEDIUM CONFIDENCE WITH AT LEAST A LITTLE FREEZING RAIN AT ONSET OF
  PRECIPITATION BETWEEN 08Z-13Z SATURDAY. HIGH CONFIDENCE
  PRECIPITATION WILL THEN CHANGE TO RAIN DURING THE MID-MORNING.

&&

.PREV DISCUSSION...ISSUED 343 AM EST FRI NOV 21 2014

SHORT TERM...TODAY AND TONIGHT

AMPLIFIED UPPER LEVEL RIDGE AXIS WILL SLIDE OVER THE CENTRAL GREAT
LAKES THIS AFTERNOON/EVENING. INVERSION HEIGHTS WILL BE CRASHING
DOWN THIS MORNING...SUB 4000 FEET...EFFECTIVELY ENDING ANY THREAT
OF ADDITIONAL LAKE EFFECT FLURRIES/SNOW SHOWERS BY AROUND
NOON...WITH WARM ADVECTION PATTERN KICKING IN THIS AFTERNOON...AS
850 MB TEMPS RISE INTO THE NEGATIVE LOW SINGLE NUMBERS TOWARD 00Z
SATURDAY. STILL...WITH THE COLD START...LATE NOVEMBER INSOLATION
AND SNOW COVER ACROSS MUCH OF SOUTHEAST MICHIGAN...MAX TEMPS WILL
PROBABLY FALL SHORT OF 30 DEGREES (BASED ON THE 925 MB TEMPS
FORECAST OF -9 C). CLEAR SKIES AND WINDS ATTEMPTING TO DECOUPLE
EARLY THIS EVENING SHOULD ALLOW MOST LOCATIONS TO DIP INTO UPPER
TEENS TO AROUND 20 DEGREES BEFORE CLOUDS AND INCREASING WARM
ADVECTION PATTERN TAKES OVER. STRUNG OUT UPPER LEVEL PV
ADVECTION/GOOD ISENTROPIC ASCENT (285-290-295 K) VERY LATE TONIGHT
(9-12 Z) WILL SUPPORT A CHANCE OF SOME TYPE OF FROZEN
PRECIPITATION...WITH BORDERLINE 3 C WARM LAYER (925-850 MB)
INDICATED. ANY FREEZING RAIN/SLEET/SNOW WILL ULTIMATELY BE
DEPENDENT ON PRECIPITATION RATE/WET BULBING EFFECTS...AS 850-700
MB WET BULB TEMP REMAINS AT OR BELOW FREEZING THROUGH 12Z SATURDAY
(PER 00Z NAM).

LONG TERM...

SATURDAY MORNING...EXTENSIVE PATTERN OF WARM AIR ADVECTION WORKING
INTO THE EXITING ARCTIC AIRMASS WILL BE WELL UNDER WAY BY EARLY
SATURDAY.  SLIVER OF STRONGER 285-290K ISENTROPIC ASCENT LODGED
ALONG THE SOUTHERN PERIPHERY OF A WEAK PV FILAMENT WILL TRANSLATE
THROUGH SE MICHIGAN DURING THE LATTER HALF OF THE MORNING PERIOD.
THIS WILL MAINTAIN A CHANCE FOR LIGHT PRECIPITATION PRODUCTION
DURING THIS TIME.  STEADY WARMING THROUGH THE COLUMN AT THE SAME
TIME WILL LEAVE A FIRM WARM NOSE/MELTING LAYER AT 900-800
MB...RECENT SOUNDINGS ON THE NAM AND GFS SHOWING A MEAN TEMPERATURE
OF 3-4C WITHIN THIS LAYER.  SOME LAG TO THE RESPONSE IN THE NEAR
SURFACE LAYER WILL PRESENT A NARROW 3-4 HOUR WINDOW /12-16Z/ FOR
LIGHT FREEZING RAIN AS THIS LAYER WORKS TO CLIMB ABOVE FREEZING.  A
RAPIDLY WARMING THERMAL PROFLE AND THE LIMITED DURATION/INTENSITY
AND CORRESPONDING LOW QPF /A FEW HUNDREDTHS/ WILL CONTAIN THE
POTENTIAL FOR ICE ACCRETION... PERHAPS GENERATING A FEW SLICK SPOTS
ON ELEVATED SURFACES.

SATURDAY AFTERNOON AND EVENING...PERSISTENT BUT WEAK ASCENT WITHIN A
STRONGLY SHEARED WEST-SOUTHWEST FLOW/ADVECTIVE PROCESS WILL SUSTAIN
A SATURATED PROFILE IN THE LOWEST 5 TO 6K FT DURING THE LATTER HALF
OF THE DAY AND INTO THE EVENING PERIOD.  SE MICHIGAN SETTLES ALONG
THE NORTHERN PERIPHERY OF AN ANTICYLONIC UPPER JET CORE DURING THIS
TIME...SOME DEGREE OF WEAKER FRONTAL FORCING OR CONVERGENCE HOLDING
IN PLACE.  SUFFICIENT DEPTH INTO THE TOP OF THE INVERSION LAYER TO
SUGGEST SOME POCKETS OF LIGHT RAIN OR DRIZZLE WILL EMERGE AT TIMES
IN THIS ENVIRONMENT... WORTHY OF A LOW POP MENTION.  LATE AFTERNOON
TEMPERATURES IN THE VICINITY OF 40 DEGREES.

REST OF THE WEEKEND...DYNAMIC SOUTHERN STREAM WAVE WILL EJECT
NORTHEAST OUT OF TEXAS SATURDAY NIGHT...REACHING THE GREAT LAKES BY
LATE SUNDAY.  THIS PROCESS WILL PROVIDE A RENEWED INCREASE IN MOIST
ISENTROPIC ASCENT DOWNSTREAM ANCHORED ON A SECONDARY WARM FRONTAL
BOUNDARY.   THIS FORCING WILL WORK ACROSS SE MICHIGAN EARLY
SUNDAY...YIELDING AN UPTICK IN RAIN CHANCES THROUGH THIS TIME.   THE
EXTENSIVE CLOUD COVER AND A SLIGHT EASTERLY COMPONENT TO THE LOW
LEVEL WIND FIELD WILL CAP HIGHS SUNDAY  IN THE MIDDLE AND UPPER 40S.
A DEEPER MOISTURE PLUME WILL THEN ACCOMPANY THE ARRIVAL OF THE MAIN
MID LEVEL ASCENT/VORTICITY AXIS DURING THE SUNDAY EVENING/NIGHT
PERIOD.  HIGH CONFIDENCE FOR A WIDESPREAD COVERAGE OF SHOWERS GIVEN
THE DEGREE OF FORCING AND MOISTURE QUALITY DURING THIS TIME...WORTHY
OF AN UPGRADE TO CATEGORICAL POPS.

EARLY NEXT WEEK...INITIAL PERIOD OF WEAK COLD AIR ADVECTION ENSUES
ON MONDAY AS THE ASSOCIATED DEEP SURFACE LOW EXITS NORTHWARD THROUGH
NORTHERN LAKE HURON.  A PERIOD OF STRONGER CONVERGENCE ALONG THE
PASSING COLD FRONT MAY PROVIDE AN ADDITIONAL ROUND OF SHOWERS DURING
THE DAYLIGHT PERIOD.  TRAILING NORTHERN STREAM TROUGH WILL THEN
PROVIDE A STRONGER DOWNWARD SPIRAL IN TEMPERATURES BY TUESDAY... 850
MB TEMPERATURE PROJECTED TO FALL BELOW -10C ONCE AGAIN.  THIS MOIST
CYCLONIC FLOW AND COLD AIR ADVECTION WILL PROVIDE THE NEXT
OPPORTUNITY FOR SNOW SHOWERS WITHIN MONDAY NIGHT AND TUESDAY
TIMEFRAME.

MARINE...

WINDS WILL EASE A BIT TODAY WHILE SHIFTING TO SOUTHWESTERLY IN
RESPONSE PASSING HIGH PRESSURE.  SOUTHWEST WINDS WILL STRENGTHEN
AGAIN HEADING INTO THE EVENING...A PERIOD OF PEAK WINDS IN EXCESS OF
20 KNOTS EMERGING THROUGHOUT LAKE HURON BY TONIGHT.  THE POTENTIAL
DOES EXIST FOR GUSTS TO APPROACH MARGINAL GALES ACROSS CENTRAL
PORTIONS OF THE LAKE TONIGHT THROUGH EARLY SATURDAY.  A GALE WATCH
IS NOW IN EFFECT FOR THIS CORRIDOR.  A DIMINISHING GRADIENT WILL
PROVIDE A GRADUAL DECREASE OF SOUTHERLY WIND SPEEDS SATURDAY NIGHT
AND SUNDAY.  SOUTHEAST FLOW WILL STRENGTHEN IN RESPONSE SUNDAY
NIGHT TO STRONG LOW PRESSURE TRACKING BY TO THE WEST.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM 9 PM EST THIS EVENING THROUGH SATURDAY MORNING FOR
     LHZ362-363.

     SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 4 PM EST SATURDAY
     FOR LHZ421.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....HLO
SHORT TERM...SF
LONG TERM....MR
MARINE.......MR


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 211731
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1231 PM EST FRI NOV 21 2014


.AVIATION...

//DISCUSSION...

HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL KEEP MAINTAIN VFR
CONDITIONS TODAY...BUT THERE WILL BE A SOME CU THAT DEVELOPS BETWEEN
2500 AND 3500 FEET. THE HIGH WILL SHIFT TOWARDS THE EAST COAST
TONIGHT...ALLOWING CLOUDS TO SPREAD INTO THE AREA. A WARM
FRONT...INITIALLY ELEVATED...WILL THEN LIFT UP INTO LOWER MICHIGAN
LATE TONIGHT AND SATURDAY. THIS WILL ALLOW A WARMER LAYER OF AIR TO
SETTLE IN OVER SUB-FREEZING AIR AT THE SURFACE...POTENTIALLY LEADING
TO FREEZING RAIN AND SLEET AS MOISTURE AND LIFT ARRIVE WITH THE
FRONT. A PERIOD OF FREEZING RAIN OR SLEET WILL BE POSSIBLE BEFORE 14-
16Z BEFORE STRONGER WARM AIR ADVECTION COMMENCES AND PRECIPITATION
CHANGES TO ALL RAIN. THE FRONT WILL ALSO ALLOW CEILINGS TO FALL TO
MVFR...WITH POSSIBLY A DROP TO IFR MID-MORNING SATURDAY.

IN ADDITION...THE LOW-LEVEL JET WILL NOSE INTO THE AREA LATE TONIGHT
AND REMAIN OVERHEAD TOMORROW RESULTING IN A STRONG CORE OF 40-50 KT
WINDS ABOVE 1500 FEET. LOW-LEVEL WIND SHEAR WAS THEREFORE ADDED TO
THE TAFS AFTER 08Z.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS FALLING BELOW 5000 FEET AFTER 09Z
  SATURDAY.

* MEDIUM CONFIDENCE WITH AT LEAST A LITTLE FREEZING RAIN AT ONSET OF
  PRECIPITATION BETWEEN 08Z-13Z SATURDAY. HIGH CONFIDENCE
  PRECIPITATION WILL THEN CHANGE TO RAIN DURING THE MID-MORNING.

&&

.PREV DISCUSSION...ISSUED 343 AM EST FRI NOV 21 2014

SHORT TERM...TODAY AND TONIGHT

AMPLIFIED UPPER LEVEL RIDGE AXIS WILL SLIDE OVER THE CENTRAL GREAT
LAKES THIS AFTERNOON/EVENING. INVERSION HEIGHTS WILL BE CRASHING
DOWN THIS MORNING...SUB 4000 FEET...EFFECTIVELY ENDING ANY THREAT
OF ADDITIONAL LAKE EFFECT FLURRIES/SNOW SHOWERS BY AROUND
NOON...WITH WARM ADVECTION PATTERN KICKING IN THIS AFTERNOON...AS
850 MB TEMPS RISE INTO THE NEGATIVE LOW SINGLE NUMBERS TOWARD 00Z
SATURDAY. STILL...WITH THE COLD START...LATE NOVEMBER INSOLATION
AND SNOW COVER ACROSS MUCH OF SOUTHEAST MICHIGAN...MAX TEMPS WILL
PROBABLY FALL SHORT OF 30 DEGREES (BASED ON THE 925 MB TEMPS
FORECAST OF -9 C). CLEAR SKIES AND WINDS ATTEMPTING TO DECOUPLE
EARLY THIS EVENING SHOULD ALLOW MOST LOCATIONS TO DIP INTO UPPER
TEENS TO AROUND 20 DEGREES BEFORE CLOUDS AND INCREASING WARM
ADVECTION PATTERN TAKES OVER. STRUNG OUT UPPER LEVEL PV
ADVECTION/GOOD ISENTROPIC ASCENT (285-290-295 K) VERY LATE TONIGHT
(9-12 Z) WILL SUPPORT A CHANCE OF SOME TYPE OF FROZEN
PRECIPITATION...WITH BORDERLINE 3 C WARM LAYER (925-850 MB)
INDICATED. ANY FREEZING RAIN/SLEET/SNOW WILL ULTIMATELY BE
DEPENDENT ON PRECIPITATION RATE/WET BULBING EFFECTS...AS 850-700
MB WET BULB TEMP REMAINS AT OR BELOW FREEZING THROUGH 12Z SATURDAY
(PER 00Z NAM).

LONG TERM...

SATURDAY MORNING...EXTENSIVE PATTERN OF WARM AIR ADVECTION WORKING
INTO THE EXITING ARCTIC AIRMASS WILL BE WELL UNDER WAY BY EARLY
SATURDAY.  SLIVER OF STRONGER 285-290K ISENTROPIC ASCENT LODGED
ALONG THE SOUTHERN PERIPHERY OF A WEAK PV FILAMENT WILL TRANSLATE
THROUGH SE MICHIGAN DURING THE LATTER HALF OF THE MORNING PERIOD.
THIS WILL MAINTAIN A CHANCE FOR LIGHT PRECIPITATION PRODUCTION
DURING THIS TIME.  STEADY WARMING THROUGH THE COLUMN AT THE SAME
TIME WILL LEAVE A FIRM WARM NOSE/MELTING LAYER AT 900-800
MB...RECENT SOUNDINGS ON THE NAM AND GFS SHOWING A MEAN TEMPERATURE
OF 3-4C WITHIN THIS LAYER.  SOME LAG TO THE RESPONSE IN THE NEAR
SURFACE LAYER WILL PRESENT A NARROW 3-4 HOUR WINDOW /12-16Z/ FOR
LIGHT FREEZING RAIN AS THIS LAYER WORKS TO CLIMB ABOVE FREEZING.  A
RAPIDLY WARMING THERMAL PROFLE AND THE LIMITED DURATION/INTENSITY
AND CORRESPONDING LOW QPF /A FEW HUNDREDTHS/ WILL CONTAIN THE
POTENTIAL FOR ICE ACCRETION... PERHAPS GENERATING A FEW SLICK SPOTS
ON ELEVATED SURFACES.

SATURDAY AFTERNOON AND EVENING...PERSISTENT BUT WEAK ASCENT WITHIN A
STRONGLY SHEARED WEST-SOUTHWEST FLOW/ADVECTIVE PROCESS WILL SUSTAIN
A SATURATED PROFILE IN THE LOWEST 5 TO 6K FT DURING THE LATTER HALF
OF THE DAY AND INTO THE EVENING PERIOD.  SE MICHIGAN SETTLES ALONG
THE NORTHERN PERIPHERY OF AN ANTICYLONIC UPPER JET CORE DURING THIS
TIME...SOME DEGREE OF WEAKER FRONTAL FORCING OR CONVERGENCE HOLDING
IN PLACE.  SUFFICIENT DEPTH INTO THE TOP OF THE INVERSION LAYER TO
SUGGEST SOME POCKETS OF LIGHT RAIN OR DRIZZLE WILL EMERGE AT TIMES
IN THIS ENVIRONMENT... WORTHY OF A LOW POP MENTION.  LATE AFTERNOON
TEMPERATURES IN THE VICINITY OF 40 DEGREES.

REST OF THE WEEKEND...DYNAMIC SOUTHERN STREAM WAVE WILL EJECT
NORTHEAST OUT OF TEXAS SATURDAY NIGHT...REACHING THE GREAT LAKES BY
LATE SUNDAY.  THIS PROCESS WILL PROVIDE A RENEWED INCREASE IN MOIST
ISENTROPIC ASCENT DOWNSTREAM ANCHORED ON A SECONDARY WARM FRONTAL
BOUNDARY.   THIS FORCING WILL WORK ACROSS SE MICHIGAN EARLY
SUNDAY...YIELDING AN UPTICK IN RAIN CHANCES THROUGH THIS TIME.   THE
EXTENSIVE CLOUD COVER AND A SLIGHT EASTERLY COMPONENT TO THE LOW
LEVEL WIND FIELD WILL CAP HIGHS SUNDAY  IN THE MIDDLE AND UPPER 40S.
A DEEPER MOISTURE PLUME WILL THEN ACCOMPANY THE ARRIVAL OF THE MAIN
MID LEVEL ASCENT/VORTICITY AXIS DURING THE SUNDAY EVENING/NIGHT
PERIOD.  HIGH CONFIDENCE FOR A WIDESPREAD COVERAGE OF SHOWERS GIVEN
THE DEGREE OF FORCING AND MOISTURE QUALITY DURING THIS TIME...WORTHY
OF AN UPGRADE TO CATEGORICAL POPS.

EARLY NEXT WEEK...INITIAL PERIOD OF WEAK COLD AIR ADVECTION ENSUES
ON MONDAY AS THE ASSOCIATED DEEP SURFACE LOW EXITS NORTHWARD THROUGH
NORTHERN LAKE HURON.  A PERIOD OF STRONGER CONVERGENCE ALONG THE
PASSING COLD FRONT MAY PROVIDE AN ADDITIONAL ROUND OF SHOWERS DURING
THE DAYLIGHT PERIOD.  TRAILING NORTHERN STREAM TROUGH WILL THEN
PROVIDE A STRONGER DOWNWARD SPIRAL IN TEMPERATURES BY TUESDAY... 850
MB TEMPERATURE PROJECTED TO FALL BELOW -10C ONCE AGAIN.  THIS MOIST
CYCLONIC FLOW AND COLD AIR ADVECTION WILL PROVIDE THE NEXT
OPPORTUNITY FOR SNOW SHOWERS WITHIN MONDAY NIGHT AND TUESDAY
TIMEFRAME.

MARINE...

WINDS WILL EASE A BIT TODAY WHILE SHIFTING TO SOUTHWESTERLY IN
RESPONSE PASSING HIGH PRESSURE.  SOUTHWEST WINDS WILL STRENGTHEN
AGAIN HEADING INTO THE EVENING...A PERIOD OF PEAK WINDS IN EXCESS OF
20 KNOTS EMERGING THROUGHOUT LAKE HURON BY TONIGHT.  THE POTENTIAL
DOES EXIST FOR GUSTS TO APPROACH MARGINAL GALES ACROSS CENTRAL
PORTIONS OF THE LAKE TONIGHT THROUGH EARLY SATURDAY.  A GALE WATCH
IS NOW IN EFFECT FOR THIS CORRIDOR.  A DIMINISHING GRADIENT WILL
PROVIDE A GRADUAL DECREASE OF SOUTHERLY WIND SPEEDS SATURDAY NIGHT
AND SUNDAY.  SOUTHEAST FLOW WILL STRENGTHEN IN RESPONSE SUNDAY
NIGHT TO STRONG LOW PRESSURE TRACKING BY TO THE WEST.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM 9 PM EST THIS EVENING THROUGH SATURDAY MORNING FOR
     LHZ362-363.

     SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 4 PM EST SATURDAY
     FOR LHZ421.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....HLO
SHORT TERM...SF
LONG TERM....MR
MARINE.......MR


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 211118
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
618 AM EST FRI NOV 21 2014

.AVIATION...

//DISCUSSION...

LINGERING LOW VFR/HIGH MVFR LAKE MICHIGAN CLOUDS WILL ATTEMPT TO
SPREAD INTO SOUTHEAST MICHIGAN THIS MORNING. HOWEVER...SURFACE RIDGE
BUILDING INTO SOUTHEAST MICHIGAN TODAY WILL PROVIDE CLEAR SKIES THIS
AFTERNOON INTO THIS EVENING. CLOUDS WILL THEN QUICKLY OVERSPREAD THE
AREA TONIGHT AS A WARM FRONT LIFTS INTO THE GREAT LAKES REGION
TOMORROW. A BRIEF WINTRY MIX OF PRECIPITATION IS POSSIBLE AROUND
SUNRISE...BUT QUICKLY CHANGING TO ALL RAIN SATURDAY MORNING...WITH
AT LEAST LOW MVFR CONDITIONS SETTLING IN.

//DTW THRESHOLD THREATS...

* LOW CONFIDENCE IN CEILINGS BELOW 5000 FEET THIS MORNING...HIGH
  CONFIDENCE TOMORROW MORNING/AFTERNOON

* LOW CONFIDENCE IN WINTRY MIX OF PRECIPITATION EARLY
  SATURDAY...HIGH CONFIDENCE PRECIPITATION WILL FALL AS RAIN MID
  MORNING SATURDAY ONWARD.

&&

.PREV DISCUSSION...ISSUED 343 AM EST FRI NOV 21 2014

SHORT TERM...TODAY AND TONIGHT

AMPLIFIED UPPER LEVEL RIDGE AXIS WILL SLIDE OVER THE CENTRAL GREAT
LAKES THIS AFTERNOON/EVENING. INVERSION HEIGHTS WILL BE CRASHING
DOWN THIS MORNING...SUB 4000 FEET...EFFECTIVELY ENDING ANY THREAT
OF ADDITIONAL LAKE EFFECT FLURRIES/SNOW SHOWERS BY AROUND
NOON...WITH WARM ADVECTION PATTERN KICKING IN THIS AFTERNOON...AS
850 MB TEMPS RISE INTO THE NEGATIVE LOW SINGLE NUMBERS TOWARD 00Z
SATURDAY. STILL...WITH THE COLD START...LATE NOVEMBER INSOLATION
AND SNOW COVER ACROSS MUCH OF SOUTHEAST MICHIGAN...MAX TEMPS WILL
PROBABLY FALL SHORT OF 30 DEGREES (BASED ON THE 925 MB TEMPS
FORECAST OF -9 C). CLEAR SKIES AND WINDS ATTEMPTING TO DECOUPLE
EARLY THIS EVENING SHOULD ALLOW MOST LOCATIONS TO DIP INTO UPPER
TEENS TO AROUND 20 DEGREES BEFORE CLOUDS AND INCREASING WARM
ADVECTION PATTERN TAKES OVER. STRUNG OUT UPPER LEVEL PV
ADVECTION/GOOD ISENTROPIC ASCENT (285-290-295 K) VERY LATE TONIGHT
(9-12 Z) WILL SUPPORT A CHANCE OF SOME TYPE OF FROZEN
PRECIPITATION...WITH BORDERLINE 3 C WARM LAYER (925-850 MB)
INDICATED. ANY FREEZING RAIN/SLEET/SNOW WILL ULTIMATELY BE
DEPENDENT ON PRECIPITATION RATE/WET BULBING EFFECTS...AS 850-700
MB WET BULB TEMP REMAINS AT OR BELOW FREEZING THROUGH 12Z SATURDAY
(PER 00Z NAM).

LONG TERM...

SATURDAY MORNING...EXTENSIVE PATTERN OF WARM AIR ADVECTION WORKING
INTO THE EXITING ARCTIC AIRMASS WILL BE WELL UNDER WAY BY EARLY
SATURDAY.  SLIVER OF STRONGER 285-290K ISENTROPIC ASCENT LODGED
ALONG THE SOUTHERN PERIPHERY OF A WEAK PV FILAMENT WILL TRANSLATE
THROUGH SE MICHIGAN DURING THE LATTER HALF OF THE MORNING PERIOD.
THIS WILL MAINTAIN A CHANCE FOR LIGHT PRECIPITATION PRODUCTION
DURING THIS TIME.  STEADY WARMING THROUGH THE COLUMN AT THE SAME
TIME WILL LEAVE A FIRM WARM NOSE/MELTING LAYER AT 900-800
MB...RECENT SOUNDINGS ON THE NAM AND GFS SHOWING A MEAN TEMPERATURE
OF 3-4C WITHIN THIS LAYER.  SOME LAG TO THE RESPONSE IN THE NEAR
SURFACE LAYER WILL PRESENT A NARROW 3-4 HOUR WINDOW /12-16Z/ FOR
LIGHT FREEZING RAIN AS THIS LAYER WORKS TO CLIMB ABOVE FREEZING.  A
RAPIDLY WARMING THERMAL PROFLE AND THE LIMITED DURATION/INTENSITY
AND CORRESPONDING LOW QPF /A FEW HUNDREDTHS/ WILL CONTAIN THE
POTENTIAL FOR ICE ACCRETION... PERHAPS GENERATING A FEW SLICK SPOTS
ON ELEVATED SURFACES.

SATURDAY AFTERNOON AND EVENING...PERSISTENT BUT WEAK ASCENT WITHIN A
STRONGLY SHEARED WEST-SOUTHWEST FLOW/ADVECTIVE PROCESS WILL SUSTAIN
A SATURATED PROFILE IN THE LOWEST 5 TO 6K FT DURING THE LATTER HALF
OF THE DAY AND INTO THE EVENING PERIOD.  SE MICHIGAN SETTLES ALONG
THE NORTHERN PERIPHERY OF AN ANTICYLONIC UPPER JET CORE DURING THIS
TIME...SOME DEGREE OF WEAKER FRONTAL FORCING OR CONVERGENCE HOLDING
IN PLACE.  SUFFICIENT DEPTH INTO THE TOP OF THE INVERSION LAYER TO
SUGGEST SOME POCKETS OF LIGHT RAIN OR DRIZZLE WILL EMERGE AT TIMES
IN THIS ENVIRONMENT... WORTHY OF A LOW POP MENTION.  LATE AFTERNOON
TEMPERATURES IN THE VICINITY OF 40 DEGREES.

REST OF THE WEEKEND...DYNAMIC SOUTHERN STREAM WAVE WILL EJECT
NORTHEAST OUT OF TEXAS SATURDAY NIGHT...REACHING THE GREAT LAKES BY
LATE SUNDAY.  THIS PROCESS WILL PROVIDE A RENEWED INCREASE IN MOIST
ISENTROPIC ASCENT DOWNSTREAM ANCHORED ON A SECONDARY WARM FRONTAL
BOUNDARY.   THIS FORCING WILL WORK ACROSS SE MICHIGAN EARLY
SUNDAY...YIELDING AN UPTICK IN RAIN CHANCES THROUGH THIS TIME.   THE
EXTENSIVE CLOUD COVER AND A SLIGHT EASTERLY COMPONENT TO THE LOW
LEVEL WIND FIELD WILL CAP HIGHS SUNDAY  IN THE MIDDLE AND UPPER 40S.
A DEEPER MOISTURE PLUME WILL THEN ACCOMPANY THE ARRIVAL OF THE MAIN
MID LEVEL ASCENT/VORTICITY AXIS DURING THE SUNDAY EVENING/NIGHT
PERIOD.  HIGH CONFIDENCE FOR A WIDESPREAD COVERAGE OF SHOWERS GIVEN
THE DEGREE OF FORCING AND MOISTURE QUALITY DURING THIS TIME...WORTHY
OF AN UPGRADE TO CATEGORICAL POPS.

EARLY NEXT WEEK...INITIAL PERIOD OF WEAK COLD AIR ADVECTION ENSUES
ON MONDAY AS THE ASSOCIATED DEEP SURFACE LOW EXITS NORTHWARD THROUGH
NORTHERN LAKE HURON.  A PERIOD OF STRONGER CONVERGENCE ALONG THE
PASSING COLD FRONT MAY PROVIDE AN ADDITIONAL ROUND OF SHOWERS DURING
THE DAYLIGHT PERIOD.  TRAILING NORTHERN STREAM TROUGH WILL THEN
PROVIDE A STRONGER DOWNWARD SPIRAL IN TEMPERATURES BY TUESDAY... 850
MB TEMPERATURE PROJECTED TO FALL BELOW -10C ONCE AGAIN.  THIS MOIST
CYCLONIC FLOW AND COLD AIR ADVECTION WILL PROVIDE THE NEXT
OPPORTUNITY FOR SNOW SHOWERS WITHIN MONDAY NIGHT AND TUESDAY
TIMEFRAME.

MARINE...

WINDS WILL EASE A BIT TODAY WHILE SHIFTING TO SOUTHWESTERLY IN
RESPONSE PASSING HIGH PRESSURE.  SOUTHWEST WINDS WILL STRENGTHEN
AGAIN HEADING INTO THE EVENING...A PERIOD OF PEAK WINDS IN EXCESS OF
20 KNOTS EMERGING THROUGHOUT LAKE HURON BY TONIGHT.  THE POTENTIAL
DOES EXIST FOR GUSTS TO APPROACH MARGINAL GALES ACROSS CENTRAL
PORTIONS OF THE LAKE TONIGHT THROUGH EARLY SATURDAY.  A GALE WATCH
IS NOW IN EFFECT FOR THIS CORRIDOR.  A DIMINISHING GRADIENT WILL
PROVIDE A GRADUAL DECREASE OF SOUTHERLY WIND SPEEDS SATURDAY NIGHT
AND SUNDAY.  SOUTHEAST FLOW WILL STRENGTHEN IN RESPONSE SUNDAY
NIGHT TO STRONG LOW PRESSURE TRACKING BY TO THE WEST.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM THIS EVENING THROUGH SATURDAY MORNING FOR LHZ362-
     363.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....SF
SHORT TERM...SF
LONG TERM....MR
MARINE.......MR

YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 211118
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
618 AM EST FRI NOV 21 2014

.AVIATION...

//DISCUSSION...

LINGERING LOW VFR/HIGH MVFR LAKE MICHIGAN CLOUDS WILL ATTEMPT TO
SPREAD INTO SOUTHEAST MICHIGAN THIS MORNING. HOWEVER...SURFACE RIDGE
BUILDING INTO SOUTHEAST MICHIGAN TODAY WILL PROVIDE CLEAR SKIES THIS
AFTERNOON INTO THIS EVENING. CLOUDS WILL THEN QUICKLY OVERSPREAD THE
AREA TONIGHT AS A WARM FRONT LIFTS INTO THE GREAT LAKES REGION
TOMORROW. A BRIEF WINTRY MIX OF PRECIPITATION IS POSSIBLE AROUND
SUNRISE...BUT QUICKLY CHANGING TO ALL RAIN SATURDAY MORNING...WITH
AT LEAST LOW MVFR CONDITIONS SETTLING IN.

//DTW THRESHOLD THREATS...

* LOW CONFIDENCE IN CEILINGS BELOW 5000 FEET THIS MORNING...HIGH
  CONFIDENCE TOMORROW MORNING/AFTERNOON

* LOW CONFIDENCE IN WINTRY MIX OF PRECIPITATION EARLY
  SATURDAY...HIGH CONFIDENCE PRECIPITATION WILL FALL AS RAIN MID
  MORNING SATURDAY ONWARD.

&&

.PREV DISCUSSION...ISSUED 343 AM EST FRI NOV 21 2014

SHORT TERM...TODAY AND TONIGHT

AMPLIFIED UPPER LEVEL RIDGE AXIS WILL SLIDE OVER THE CENTRAL GREAT
LAKES THIS AFTERNOON/EVENING. INVERSION HEIGHTS WILL BE CRASHING
DOWN THIS MORNING...SUB 4000 FEET...EFFECTIVELY ENDING ANY THREAT
OF ADDITIONAL LAKE EFFECT FLURRIES/SNOW SHOWERS BY AROUND
NOON...WITH WARM ADVECTION PATTERN KICKING IN THIS AFTERNOON...AS
850 MB TEMPS RISE INTO THE NEGATIVE LOW SINGLE NUMBERS TOWARD 00Z
SATURDAY. STILL...WITH THE COLD START...LATE NOVEMBER INSOLATION
AND SNOW COVER ACROSS MUCH OF SOUTHEAST MICHIGAN...MAX TEMPS WILL
PROBABLY FALL SHORT OF 30 DEGREES (BASED ON THE 925 MB TEMPS
FORECAST OF -9 C). CLEAR SKIES AND WINDS ATTEMPTING TO DECOUPLE
EARLY THIS EVENING SHOULD ALLOW MOST LOCATIONS TO DIP INTO UPPER
TEENS TO AROUND 20 DEGREES BEFORE CLOUDS AND INCREASING WARM
ADVECTION PATTERN TAKES OVER. STRUNG OUT UPPER LEVEL PV
ADVECTION/GOOD ISENTROPIC ASCENT (285-290-295 K) VERY LATE TONIGHT
(9-12 Z) WILL SUPPORT A CHANCE OF SOME TYPE OF FROZEN
PRECIPITATION...WITH BORDERLINE 3 C WARM LAYER (925-850 MB)
INDICATED. ANY FREEZING RAIN/SLEET/SNOW WILL ULTIMATELY BE
DEPENDENT ON PRECIPITATION RATE/WET BULBING EFFECTS...AS 850-700
MB WET BULB TEMP REMAINS AT OR BELOW FREEZING THROUGH 12Z SATURDAY
(PER 00Z NAM).

LONG TERM...

SATURDAY MORNING...EXTENSIVE PATTERN OF WARM AIR ADVECTION WORKING
INTO THE EXITING ARCTIC AIRMASS WILL BE WELL UNDER WAY BY EARLY
SATURDAY.  SLIVER OF STRONGER 285-290K ISENTROPIC ASCENT LODGED
ALONG THE SOUTHERN PERIPHERY OF A WEAK PV FILAMENT WILL TRANSLATE
THROUGH SE MICHIGAN DURING THE LATTER HALF OF THE MORNING PERIOD.
THIS WILL MAINTAIN A CHANCE FOR LIGHT PRECIPITATION PRODUCTION
DURING THIS TIME.  STEADY WARMING THROUGH THE COLUMN AT THE SAME
TIME WILL LEAVE A FIRM WARM NOSE/MELTING LAYER AT 900-800
MB...RECENT SOUNDINGS ON THE NAM AND GFS SHOWING A MEAN TEMPERATURE
OF 3-4C WITHIN THIS LAYER.  SOME LAG TO THE RESPONSE IN THE NEAR
SURFACE LAYER WILL PRESENT A NARROW 3-4 HOUR WINDOW /12-16Z/ FOR
LIGHT FREEZING RAIN AS THIS LAYER WORKS TO CLIMB ABOVE FREEZING.  A
RAPIDLY WARMING THERMAL PROFLE AND THE LIMITED DURATION/INTENSITY
AND CORRESPONDING LOW QPF /A FEW HUNDREDTHS/ WILL CONTAIN THE
POTENTIAL FOR ICE ACCRETION... PERHAPS GENERATING A FEW SLICK SPOTS
ON ELEVATED SURFACES.

SATURDAY AFTERNOON AND EVENING...PERSISTENT BUT WEAK ASCENT WITHIN A
STRONGLY SHEARED WEST-SOUTHWEST FLOW/ADVECTIVE PROCESS WILL SUSTAIN
A SATURATED PROFILE IN THE LOWEST 5 TO 6K FT DURING THE LATTER HALF
OF THE DAY AND INTO THE EVENING PERIOD.  SE MICHIGAN SETTLES ALONG
THE NORTHERN PERIPHERY OF AN ANTICYLONIC UPPER JET CORE DURING THIS
TIME...SOME DEGREE OF WEAKER FRONTAL FORCING OR CONVERGENCE HOLDING
IN PLACE.  SUFFICIENT DEPTH INTO THE TOP OF THE INVERSION LAYER TO
SUGGEST SOME POCKETS OF LIGHT RAIN OR DRIZZLE WILL EMERGE AT TIMES
IN THIS ENVIRONMENT... WORTHY OF A LOW POP MENTION.  LATE AFTERNOON
TEMPERATURES IN THE VICINITY OF 40 DEGREES.

REST OF THE WEEKEND...DYNAMIC SOUTHERN STREAM WAVE WILL EJECT
NORTHEAST OUT OF TEXAS SATURDAY NIGHT...REACHING THE GREAT LAKES BY
LATE SUNDAY.  THIS PROCESS WILL PROVIDE A RENEWED INCREASE IN MOIST
ISENTROPIC ASCENT DOWNSTREAM ANCHORED ON A SECONDARY WARM FRONTAL
BOUNDARY.   THIS FORCING WILL WORK ACROSS SE MICHIGAN EARLY
SUNDAY...YIELDING AN UPTICK IN RAIN CHANCES THROUGH THIS TIME.   THE
EXTENSIVE CLOUD COVER AND A SLIGHT EASTERLY COMPONENT TO THE LOW
LEVEL WIND FIELD WILL CAP HIGHS SUNDAY  IN THE MIDDLE AND UPPER 40S.
A DEEPER MOISTURE PLUME WILL THEN ACCOMPANY THE ARRIVAL OF THE MAIN
MID LEVEL ASCENT/VORTICITY AXIS DURING THE SUNDAY EVENING/NIGHT
PERIOD.  HIGH CONFIDENCE FOR A WIDESPREAD COVERAGE OF SHOWERS GIVEN
THE DEGREE OF FORCING AND MOISTURE QUALITY DURING THIS TIME...WORTHY
OF AN UPGRADE TO CATEGORICAL POPS.

EARLY NEXT WEEK...INITIAL PERIOD OF WEAK COLD AIR ADVECTION ENSUES
ON MONDAY AS THE ASSOCIATED DEEP SURFACE LOW EXITS NORTHWARD THROUGH
NORTHERN LAKE HURON.  A PERIOD OF STRONGER CONVERGENCE ALONG THE
PASSING COLD FRONT MAY PROVIDE AN ADDITIONAL ROUND OF SHOWERS DURING
THE DAYLIGHT PERIOD.  TRAILING NORTHERN STREAM TROUGH WILL THEN
PROVIDE A STRONGER DOWNWARD SPIRAL IN TEMPERATURES BY TUESDAY... 850
MB TEMPERATURE PROJECTED TO FALL BELOW -10C ONCE AGAIN.  THIS MOIST
CYCLONIC FLOW AND COLD AIR ADVECTION WILL PROVIDE THE NEXT
OPPORTUNITY FOR SNOW SHOWERS WITHIN MONDAY NIGHT AND TUESDAY
TIMEFRAME.

MARINE...

WINDS WILL EASE A BIT TODAY WHILE SHIFTING TO SOUTHWESTERLY IN
RESPONSE PASSING HIGH PRESSURE.  SOUTHWEST WINDS WILL STRENGTHEN
AGAIN HEADING INTO THE EVENING...A PERIOD OF PEAK WINDS IN EXCESS OF
20 KNOTS EMERGING THROUGHOUT LAKE HURON BY TONIGHT.  THE POTENTIAL
DOES EXIST FOR GUSTS TO APPROACH MARGINAL GALES ACROSS CENTRAL
PORTIONS OF THE LAKE TONIGHT THROUGH EARLY SATURDAY.  A GALE WATCH
IS NOW IN EFFECT FOR THIS CORRIDOR.  A DIMINISHING GRADIENT WILL
PROVIDE A GRADUAL DECREASE OF SOUTHERLY WIND SPEEDS SATURDAY NIGHT
AND SUNDAY.  SOUTHEAST FLOW WILL STRENGTHEN IN RESPONSE SUNDAY
NIGHT TO STRONG LOW PRESSURE TRACKING BY TO THE WEST.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM THIS EVENING THROUGH SATURDAY MORNING FOR LHZ362-
     363.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

AVIATION.....SF
SHORT TERM...SF
LONG TERM....MR
MARINE.......MR

YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 210843
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
343 AM EST FRI NOV 21 2014

.SHORT TERM...TODAY AND TONIGHT

AMPLIFIED UPPER LEVEL RIDGE AXIS WILL SLIDE OVER THE CENTRAL GREAT
LAKES THIS AFTERNOON/EVENING. INVERSION HEIGHTS WILL BE CRASHING
DOWN THIS MORNING...SUB 4000 FEET...EFFECTIVELY ENDING ANY THREAT
OF ADDITIONAL LAKE EFFECT FLURRIES/SNOW SHOWERS BY AROUND
NOON...WITH WARM ADVECTION PATTERN KICKING IN THIS AFTERNOON...AS
850 MB TEMPS RISE INTO THE NEGATIVE LOW SINGLE NUMBERS TOWARD 00Z
SATURDAY. STILL...WITH THE COLD START...LATE NOVEMBER INSOLATION
AND SNOW COVER ACROSS MUCH OF SOUTHEAST MICHIGAN...MAX TEMPS WILL
PROBABLY FALL SHORT OF 30 DEGREES (BASED ON THE 925 MB TEMPS
FORECAST OF -9 C). CLEAR SKIES AND WINDS ATTEMPTING TO DECOUPLE
EARLY THIS EVENING SHOULD ALLOW MOST LOCATIONS TO DIP INTO UPPER
TEENS TO AROUND 20 DEGREES BEFORE CLOUDS AND INCREASING WARM
ADVECTION PATTERN TAKES OVER. STRUNG OUT UPPER LEVEL PV
ADVECTION/GOOD ISENTROPIC ASCENT (285-290-295 K) VERY LATE TONIGHT
(9-12 Z) WILL SUPPORT A CHANCE OF SOME TYPE OF FROZEN
PRECIPITATION...WITH BORDERLINE 3 C WARM LAYER (925-850 MB)
INDICATED. ANY FREEZING RAIN/SLEET/SNOW WILL ULTIMATELY BE
DEPENDENT ON PRECIPITATION RATE/WET BULBING EFFECTS...AS 850-700
MB WET BULB TEMP REMAINS AT OR BELOW FREEZING THROUGH 12Z SATURDAY
(PER 00Z NAM).

&&

.LONG TERM...

SATURDAY MORNING...EXTENSIVE PATTERN OF WARM AIR ADVECTION WORKING
INTO THE EXITING ARCTIC AIRMASS WILL BE WELL UNDER WAY BY EARLY
SATURDAY.  SLIVER OF STRONGER 285-290K ISENTROPIC ASCENT LODGED
ALONG THE SOUTHERN PERIPHERY OF A WEAK PV FILAMENT WILL TRANSLATE
THROUGH SE MICHIGAN DURING THE LATTER HALF OF THE MORNING PERIOD.
THIS WILL MAINTAIN A CHANCE FOR LIGHT PRECIPITATION PRODUCTION
DURING THIS TIME.  STEADY WARMING THROUGH THE COLUMN AT THE SAME
TIME WILL LEAVE A FIRM WARM NOSE/MELTING LAYER AT 900-800
MB...RECENT SOUNDINGS ON THE NAM AND GFS SHOWING A MEAN TEMPERATURE
OF 3-4C WITHIN THIS LAYER.  SOME LAG TO THE RESPONSE IN THE NEAR
SURFACE LAYER WILL PRESENT A NARROW 3-4 HOUR WINDOW /12-16Z/ FOR
LIGHT FREEZING RAIN AS THIS LAYER WORKS TO CLIMB ABOVE FREEZING.  A
RAPIDLY WARMING THERMAL PROFLE AND THE LIMITED DURATION/INTENSITY
AND CORRESPONDING LOW QPF /A FEW HUNDREDTHS/ WILL CONTAIN THE
POTENTIAL FOR ICE ACCRETION... PERHAPS GENERATING A FEW SLICK SPOTS
ON ELEVATED SURFACES.

SATURDAY AFTERNOON AND EVENING...PERSISTENT BUT WEAK ASCENT WITHIN A
STRONGLY SHEARED WEST-SOUTHWEST FLOW/ADVECTIVE PROCESS WILL SUSTAIN
A SATURATED PROFILE IN THE LOWEST 5 TO 6K FT DURING THE LATTER HALF
OF THE DAY AND INTO THE EVENING PERIOD.  SE MICHIGAN SETTLES ALONG
THE NORTHERN PERIPHERY OF AN ANTICYLONIC UPPER JET CORE DURING THIS
TIME...SOME DEGREE OF WEAKER FRONTAL FORCING OR CONVERGENCE HOLDING
IN PLACE.  SUFFICIENT DEPTH INTO THE TOP OF THE INVERSION LAYER TO
SUGGEST SOME POCKETS OF LIGHT RAIN OR DRIZZLE WILL EMERGE AT TIMES
IN THIS ENVIRONMENT... WORTHY OF A LOW POP MENTION.  LATE AFTERNOON
TEMPERATURES IN THE VICINITY OF 40 DEGREES.

REST OF THE WEEKEND...DYNAMIC SOUTHERN STREAM WAVE WILL EJECT
NORTHEAST OUT OF TEXAS SATURDAY NIGHT...REACHING THE GREAT LAKES BY
LATE SUNDAY.  THIS PROCESS WILL PROVIDE A RENEWED INCREASE IN MOIST
ISENTROPIC ASCENT DOWNSTREAM ANCHORED ON A SECONDARY WARM FRONTAL
BOUNDARY.   THIS FORCING WILL WORK ACROSS SE MICHIGAN EARLY
SUNDAY...YIELDING AN UPTICK IN RAIN CHANCES THROUGH THIS TIME.   THE
EXTENSIVE CLOUD COVER AND A SLIGHT EASTERLY COMPONENT TO THE LOW
LEVEL WIND FIELD WILL CAP HIGHS SUNDAY  IN THE MIDDLE AND UPPER 40S.
A DEEPER MOISTURE PLUME WILL THEN ACCOMPANY THE ARRIVAL OF THE MAIN
MID LEVEL ASCENT/VORTICITY AXIS DURING THE SUNDAY EVENING/NIGHT
PERIOD.  HIGH CONFIDENCE FOR A WIDESPREAD COVERAGE OF SHOWERS GIVEN
THE DEGREE OF FORCING AND MOISTURE QUALITY DURING THIS TIME...WORTHY
OF AN UPGRADE TO CATEGORICAL POPS.

EARLY NEXT WEEK...INITIAL PERIOD OF WEAK COLD AIR ADVECTION ENSUES
ON MONDAY AS THE ASSOCIATED DEEP SURFACE LOW EXITS NORTHWARD THROUGH
NORTHERN LAKE HURON.  A PERIOD OF STRONGER CONVERGENCE ALONG THE
PASSING COLD FRONT MAY PROVIDE AN ADDITIONAL ROUND OF SHOWERS DURING
THE DAYLIGHT PERIOD.  TRAILING NORTHERN STREAM TROUGH WILL THEN
PROVIDE A STRONGER DOWNWARD SPIRAL IN TEMPERATURES BY TUESDAY... 850
MB TEMPERATURE PROJECTED TO FALL BELOW -10C ONCE AGAIN.  THIS MOIST
CYCLONIC FLOW AND COLD AIR ADVECTION WILL PROVIDE THE NEXT
OPPORTUNITY FOR SNOW SHOWERS WITHIN MONDAY NIGHT AND TUESDAY
TIMEFRAME.

&&

.MARINE...

WINDS WILL EASE A BIT TODAY WHILE SHIFTING TO SOUTHWESTERLY IN
RESPONSE PASSING HIGH PRESSURE.  SOUTHWEST WINDS WILL STRENGTHEN
AGAIN HEADING INTO THE EVENING...A PERIOD OF PEAK WINDS IN EXCESS OF
20 KNOTS EMERGING THROUGHOUT LAKE HURON BY TONIGHT.  THE POTENTIAL
DOES EXIST FOR GUSTS TO APPROACH MARGINAL GALES ACROSS CENTRAL
PORTIONS OF THE LAKE TONIGHT THROUGH EARLY SATURDAY.  A GALE WATCH
IS NOW IN EFFECT FOR THIS CORRIDOR.  A DIMINISHING GRADIENT WILL
PROVIDE A GRADUAL DECREASE OF SOUTHERLY WIND SPEEDS SATURDAY NIGHT
AND SUNDAY.  SOUTHEAST FLOW WILL STRENGTHEN IN RESPONSE SUNDAY
NIGHT TO STRONG LOW PRESSURE TRACKING BY TO THE WEST.

&&

.AVIATION...ISSUED 1149 PM EST THU NOV 20 2014

//DISCUSSION...

LAKE EFFECT SNOW SHOWERS HAVE ALL BUT ENDED FOR THE TAF SITES
OVERNIGHT...WITH THE LONE EXCEPTION BEING YIP WHERE SOME LINGERING
FLURRIES AND VERY LIGHT SNOW CONTINUES. OUTSIDE OF THIS MOST TAF
SITES HAVE CLEARED OR HAVE RISEN TO VFR.  THIS IS EXPECTED TO
CONTINUE THROUGHT DAYTIME HOURS ON FRIDAY AND INTO FRIDAY NIGHT AS A
RIDGE OF HIGH PRESSURE TRACKS THROUGH THE CENTRAL GREAT LAKES.

//DTW THRESHOLD THREATS...

* NONE.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR LHZ421-
     441>443.

     GALE WATCH FROM THIS EVENING THROUGH SATURDAY MORNING FOR LHZ362-
     363.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

SHORT TERM...SF
LONG TERM....MR
MARINE.......MR
AVIATION.....KURIMSKI


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 210843
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
343 AM EST FRI NOV 21 2014

.SHORT TERM...TODAY AND TONIGHT

AMPLIFIED UPPER LEVEL RIDGE AXIS WILL SLIDE OVER THE CENTRAL GREAT
LAKES THIS AFTERNOON/EVENING. INVERSION HEIGHTS WILL BE CRASHING
DOWN THIS MORNING...SUB 4000 FEET...EFFECTIVELY ENDING ANY THREAT
OF ADDITIONAL LAKE EFFECT FLURRIES/SNOW SHOWERS BY AROUND
NOON...WITH WARM ADVECTION PATTERN KICKING IN THIS AFTERNOON...AS
850 MB TEMPS RISE INTO THE NEGATIVE LOW SINGLE NUMBERS TOWARD 00Z
SATURDAY. STILL...WITH THE COLD START...LATE NOVEMBER INSOLATION
AND SNOW COVER ACROSS MUCH OF SOUTHEAST MICHIGAN...MAX TEMPS WILL
PROBABLY FALL SHORT OF 30 DEGREES (BASED ON THE 925 MB TEMPS
FORECAST OF -9 C). CLEAR SKIES AND WINDS ATTEMPTING TO DECOUPLE
EARLY THIS EVENING SHOULD ALLOW MOST LOCATIONS TO DIP INTO UPPER
TEENS TO AROUND 20 DEGREES BEFORE CLOUDS AND INCREASING WARM
ADVECTION PATTERN TAKES OVER. STRUNG OUT UPPER LEVEL PV
ADVECTION/GOOD ISENTROPIC ASCENT (285-290-295 K) VERY LATE TONIGHT
(9-12 Z) WILL SUPPORT A CHANCE OF SOME TYPE OF FROZEN
PRECIPITATION...WITH BORDERLINE 3 C WARM LAYER (925-850 MB)
INDICATED. ANY FREEZING RAIN/SLEET/SNOW WILL ULTIMATELY BE
DEPENDENT ON PRECIPITATION RATE/WET BULBING EFFECTS...AS 850-700
MB WET BULB TEMP REMAINS AT OR BELOW FREEZING THROUGH 12Z SATURDAY
(PER 00Z NAM).

&&

.LONG TERM...

SATURDAY MORNING...EXTENSIVE PATTERN OF WARM AIR ADVECTION WORKING
INTO THE EXITING ARCTIC AIRMASS WILL BE WELL UNDER WAY BY EARLY
SATURDAY.  SLIVER OF STRONGER 285-290K ISENTROPIC ASCENT LODGED
ALONG THE SOUTHERN PERIPHERY OF A WEAK PV FILAMENT WILL TRANSLATE
THROUGH SE MICHIGAN DURING THE LATTER HALF OF THE MORNING PERIOD.
THIS WILL MAINTAIN A CHANCE FOR LIGHT PRECIPITATION PRODUCTION
DURING THIS TIME.  STEADY WARMING THROUGH THE COLUMN AT THE SAME
TIME WILL LEAVE A FIRM WARM NOSE/MELTING LAYER AT 900-800
MB...RECENT SOUNDINGS ON THE NAM AND GFS SHOWING A MEAN TEMPERATURE
OF 3-4C WITHIN THIS LAYER.  SOME LAG TO THE RESPONSE IN THE NEAR
SURFACE LAYER WILL PRESENT A NARROW 3-4 HOUR WINDOW /12-16Z/ FOR
LIGHT FREEZING RAIN AS THIS LAYER WORKS TO CLIMB ABOVE FREEZING.  A
RAPIDLY WARMING THERMAL PROFLE AND THE LIMITED DURATION/INTENSITY
AND CORRESPONDING LOW QPF /A FEW HUNDREDTHS/ WILL CONTAIN THE
POTENTIAL FOR ICE ACCRETION... PERHAPS GENERATING A FEW SLICK SPOTS
ON ELEVATED SURFACES.

SATURDAY AFTERNOON AND EVENING...PERSISTENT BUT WEAK ASCENT WITHIN A
STRONGLY SHEARED WEST-SOUTHWEST FLOW/ADVECTIVE PROCESS WILL SUSTAIN
A SATURATED PROFILE IN THE LOWEST 5 TO 6K FT DURING THE LATTER HALF
OF THE DAY AND INTO THE EVENING PERIOD.  SE MICHIGAN SETTLES ALONG
THE NORTHERN PERIPHERY OF AN ANTICYLONIC UPPER JET CORE DURING THIS
TIME...SOME DEGREE OF WEAKER FRONTAL FORCING OR CONVERGENCE HOLDING
IN PLACE.  SUFFICIENT DEPTH INTO THE TOP OF THE INVERSION LAYER TO
SUGGEST SOME POCKETS OF LIGHT RAIN OR DRIZZLE WILL EMERGE AT TIMES
IN THIS ENVIRONMENT... WORTHY OF A LOW POP MENTION.  LATE AFTERNOON
TEMPERATURES IN THE VICINITY OF 40 DEGREES.

REST OF THE WEEKEND...DYNAMIC SOUTHERN STREAM WAVE WILL EJECT
NORTHEAST OUT OF TEXAS SATURDAY NIGHT...REACHING THE GREAT LAKES BY
LATE SUNDAY.  THIS PROCESS WILL PROVIDE A RENEWED INCREASE IN MOIST
ISENTROPIC ASCENT DOWNSTREAM ANCHORED ON A SECONDARY WARM FRONTAL
BOUNDARY.   THIS FORCING WILL WORK ACROSS SE MICHIGAN EARLY
SUNDAY...YIELDING AN UPTICK IN RAIN CHANCES THROUGH THIS TIME.   THE
EXTENSIVE CLOUD COVER AND A SLIGHT EASTERLY COMPONENT TO THE LOW
LEVEL WIND FIELD WILL CAP HIGHS SUNDAY  IN THE MIDDLE AND UPPER 40S.
A DEEPER MOISTURE PLUME WILL THEN ACCOMPANY THE ARRIVAL OF THE MAIN
MID LEVEL ASCENT/VORTICITY AXIS DURING THE SUNDAY EVENING/NIGHT
PERIOD.  HIGH CONFIDENCE FOR A WIDESPREAD COVERAGE OF SHOWERS GIVEN
THE DEGREE OF FORCING AND MOISTURE QUALITY DURING THIS TIME...WORTHY
OF AN UPGRADE TO CATEGORICAL POPS.

EARLY NEXT WEEK...INITIAL PERIOD OF WEAK COLD AIR ADVECTION ENSUES
ON MONDAY AS THE ASSOCIATED DEEP SURFACE LOW EXITS NORTHWARD THROUGH
NORTHERN LAKE HURON.  A PERIOD OF STRONGER CONVERGENCE ALONG THE
PASSING COLD FRONT MAY PROVIDE AN ADDITIONAL ROUND OF SHOWERS DURING
THE DAYLIGHT PERIOD.  TRAILING NORTHERN STREAM TROUGH WILL THEN
PROVIDE A STRONGER DOWNWARD SPIRAL IN TEMPERATURES BY TUESDAY... 850
MB TEMPERATURE PROJECTED TO FALL BELOW -10C ONCE AGAIN.  THIS MOIST
CYCLONIC FLOW AND COLD AIR ADVECTION WILL PROVIDE THE NEXT
OPPORTUNITY FOR SNOW SHOWERS WITHIN MONDAY NIGHT AND TUESDAY
TIMEFRAME.

&&

.MARINE...

WINDS WILL EASE A BIT TODAY WHILE SHIFTING TO SOUTHWESTERLY IN
RESPONSE PASSING HIGH PRESSURE.  SOUTHWEST WINDS WILL STRENGTHEN
AGAIN HEADING INTO THE EVENING...A PERIOD OF PEAK WINDS IN EXCESS OF
20 KNOTS EMERGING THROUGHOUT LAKE HURON BY TONIGHT.  THE POTENTIAL
DOES EXIST FOR GUSTS TO APPROACH MARGINAL GALES ACROSS CENTRAL
PORTIONS OF THE LAKE TONIGHT THROUGH EARLY SATURDAY.  A GALE WATCH
IS NOW IN EFFECT FOR THIS CORRIDOR.  A DIMINISHING GRADIENT WILL
PROVIDE A GRADUAL DECREASE OF SOUTHERLY WIND SPEEDS SATURDAY NIGHT
AND SUNDAY.  SOUTHEAST FLOW WILL STRENGTHEN IN RESPONSE SUNDAY
NIGHT TO STRONG LOW PRESSURE TRACKING BY TO THE WEST.

&&

.AVIATION...ISSUED 1149 PM EST THU NOV 20 2014

//DISCUSSION...

LAKE EFFECT SNOW SHOWERS HAVE ALL BUT ENDED FOR THE TAF SITES
OVERNIGHT...WITH THE LONE EXCEPTION BEING YIP WHERE SOME LINGERING
FLURRIES AND VERY LIGHT SNOW CONTINUES. OUTSIDE OF THIS MOST TAF
SITES HAVE CLEARED OR HAVE RISEN TO VFR.  THIS IS EXPECTED TO
CONTINUE THROUGHT DAYTIME HOURS ON FRIDAY AND INTO FRIDAY NIGHT AS A
RIDGE OF HIGH PRESSURE TRACKS THROUGH THE CENTRAL GREAT LAKES.

//DTW THRESHOLD THREATS...

* NONE.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR LHZ421-
     441>443.

     GALE WATCH FROM THIS EVENING THROUGH SATURDAY MORNING FOR LHZ362-
     363.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&

$$

SHORT TERM...SF
LONG TERM....MR
MARINE.......MR
AVIATION.....KURIMSKI


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 210449
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1149 PM EST THU NOV 20 2014


.AVIATION...

//DISCUSSION...

LAKE EFFECT SNOW SHOWERS HAVE ALL BUT ENDED FOR THE TAF SITES
OVERNIGHT...WITH THE LONE EXCEPTION BEING YIP WHERE SOME LINGERING
FLURRIES AND VERY LIGHT SNOW CONTINUES. OUTSIDE OF THIS MOST TAF
SITES HAVE CLEARED OR HAVE RISEN TO VFR.  THIS IS EXPECTED TO
CONTINUE THROUGHT DAYTIME HOURS ON FRIDAY AND INTO FRIDAY NIGHT AS A
RIDGE OF HIGH PRESSURE TRACKS THROUGH THE CENTRAL GREAT LAKES.

//DTW THRESHOLD THREATS...

* NONE.

&&

.PREV DISCUSSION...ISSUED DETROIT/PONTIAC MI 319 PM EST THU NOV 20 2014

SHORT TERM...THIS EVENING AND TONIGHT

THE ONGOING SNOW SHOWERS ACROSS PORTIONS OF THE FORECAST AREA HAVE
BEEN THE RESULT OF LAKE EFFECT OFF LAKE MI...SUSTAINED THIS FAR EAST
BY STRONG WSW FLOW WITHIN AN ENHANCED W-E BOUNDARY LAYER CONVERGENCE
AXIS. CONVECTIVE UPDRAFTS HAVE BEEN WITHIN THE GOOD DENDRITIC GROWTH
LAYER...SO FLAKE SIZE HAS BEEN RESPECTABLE. A LONGER LIVED HEAVY BAND
OF SNOW IMPACTED LOCATIONS ALONG AN AXIS FROM SRN SHIAWASSEE/SRN
GENESEE/NRN OAKLAND COUNTIES INTO THE PORT HURON AREA EARLIER TODAY.
SPOTTER REPORTS SUGGEST A SOLID 3 TO 5 INCHES FELL IN THESE AREAS.
WHILE ACCUMULATIONS HAVE BEEN MUCH LESS OUTSIDE OF THIS REGION...THE
INTENSE SNOW SHOWERS HAVE STILL BEEN LEADING TO SPORADIC REDUCTIONS
IN VISIBILITIES AND A QUICK DUSTING OF ACCUMULATION. WINDS HAVE ALSO
INCREASED THIS AFTERNOON /WITH SOME GUSTS OVER 30 MPH REPORTED/
WHICH HAS BEEN CAUSING SOME BLOWING SNOW AND MINOR DRIFTING IN THE
ADVISORY AREA.

ONGOING MID LEVEL COLD AIR ADVECTION AND DAYTIME HEATING HAS BEEN
LIFTING CONVECTIVE DEPTHS THIS AFTERNOON. THIS HAS ACTUALLY RESULTED
IN SOME DISRUPTION TO THE MORE ORGANIZED BANDING. DEEPER MIXING HAS
ALSO LED TO A MORE UNIFORM WESTERLY SURFACE WIND ACROSS SRN
MI...WEAKENING THE CONVERGENCE IN THE BOUNDARY LAYER. THE PREVAILING
WESTERLY FLOW WILL STILL FOCUS THE MORE WIDESPREAD SNOW SHOWER
ACTIVITY ACROSS THE ADVISORY AREA THROUGH EVENING RUSH HOUR. VEERING
OF THE LOW LEVEL FLOW TOWARD THE NORTHWEST DURING THE COURSE OF THE
NIGHT WILL FOCUS THE MORE NUMEROUS SNOW SHOWERS SOUTH OF THE I-
96/696 CORRIDOR LATER THIS EVENING. THERE WILL BE AN OVERALL
WEAKENING TREND TO LAKE EFFECT DURING THE NIGHT UNDER CONTINUED LOW
LEVEL DRY AIR ADVECTION AND LOWERING CONVECTIVE DEPTHS AS A RESULT
OF INCREASING LARGE SCALE SUBSIDENCE. THIS WILL DIMINISH THE OVERALL
COVERAGE OF SNOW SHOWERS. A TRANSITION TOWARD MORE DOMINATE BANDING
IS POSSIBLE PRIOR TO DAYBREAK...WHICH MAY IMPACT FAR SOUTHERN
COUNTIES LATER TONIGHT. THIS IS A FAIRLY LOW CONFIDENCE
SCENARIO...SUGGESTING HOLDING JUST MINOR ADDITIONAL ACCUMULATIONS
TONIGHT ATTM. THE VEERING OF THE FLOW TOWARD THE NORTHWEST AND LOW
LEVEL DRY AIR ADVECTION WILL LEAD TO SOME CLEARING DURING THE COURSE
OF THE NIGHT /ESPECIALLY ACROSS THE SAGINAW VALLEY AND THUMB/. THIS
AND A GRADUAL WEAKENING GRADIENT WILL OFFER AN OPPORTUNITY FOR GOOD
RADIATIONAL COOLING /SUPPORTING MIN TEMPS IN THE SINGLE DIGITS TO
LOWER TEENS/.

LONG TERM...

THE SURGE OF STRONG PACIFIC ENERGY TAKING AIM ON THE PACIFIC
NORTHWEST OVER THE NEXT 24 HOURS HAS DEAMPLIFIED THE WEST COAST
RIDGE RESULTING IN A TRANSITION TO ZONAL FLOW ACROSS THE CONUS. THE
ZONAL REGIME WILL SPREAD INTO THE GREAT LAKES, FLOODING THE MID-
LEVELS WITH WARMER AIR, UPON THE DEPARTURE OF TODAY`S TROUGH.
BETWEEN 12Z FRIDAY AND 12Z SATURDAY, H85 TEMPERATURES OVER SOUTHEAST
MICHIGAN WILL RISE ABOUT 20 DEGREES AS THE MID-LEVEL CLIMB ABOVE
FREEZING BY SATURDAY MORNING. SHORTWAVE RIDGING EMBEDDED IN THE
DEVELOPING ZONAL FLOW WILL BUILD INTO THE AREA DURING THE DAY FRIDAY
AND EASE THE SURFACE HIGH OVER THE OHIO VALLEY EAST. RETURN FLOW AT
THE SURFACE WILL BE OF LITTLE HELP WITH ARCTIC AIR ENTRENCHED OVER
THE EASTERN US. TEMPERATURES WILL REMAIN IN THE UPPER TEENS/LOW 20S
TOMORROW THROUGH TOMORROW NIGHT. AS A RESULT, A STRONG INVERSION
WILL BEGIN TO TAKE SHAPE ON FRIDAY NIGHT AS THE SHORTWAVE OVER THE
INTERMOUNTAIN WEST EJECTS OUT OVER THE GREAT LAKES. ISENTROPIC
ASCENT AND A QUICK HIT OF PV ADVECTION 09Z-15Z SATURDAY MORNING WILL
SUPPORT AT LEAST A SCATTERED COVERAGE OF SHOWERS LIFTING THROUGH THE
AREA. CURRENT INDICATIONS ARE THAT THIS PRECIPITATION MAY FALL AS
FREEZING RAIN. SHORT DURATION AND LACK OF MAINTENANCE FOR SUB-ZERO
WET BULBING AT THE SURFACE LIMIT CONCERNS, BUT THE POTENTIAL FOR
SOME LIGHT ICING IS EVIDENT.

WEAK ISENTROPIC ASCENT WILL THEN BE ONGOING THROUGH THE DAY SATURDAY
AS A 100KT JET DEVELOPS OVERHEAD IN RESPONSE TO THE DEEPENING LONGWAVE
TROUGH UPSTREAM. THIS WILL HELP ORIENT A MID-LEVEL BAROCLINIC ZONE
ACROSS THE AREA WHICH WILL SERVE AS A FOCUS FOR ONGOING
PRECIPITATION DURING THE DAY. DRY MID-LEVELS SUGGEST THAT DRIZZLE,
AS OPPOSED TO SHOWERS, WILL BE WORTH KEEPING AN EYE ON. EITHER WAY,
TEMPERATURE RECOVERY DURING THIS TIME WILL BE IMPORTANT TO WATCH AS
AN ADDITIONAL FREEZING PRECIP THREAT COULD THEORETICALLY EVOLVE.
HOWEVER, THE SOLID SOUTHERLY GRADIENT COMBINED WITH THE NAM`S
TENDENCY TO HOLD ONTO LOW-LEVEL COLD AIR A BIT TOO LONG HELP
ALLEVIATE THAT CONCERN AT THIS TIME.

GLOBAL NWP REMAINS IN DECENT AGREEMENT WITH THE REST OF THE
FORECAST WITH SLIGHT DIFFERENCES IN TIMING AND LOCATION OF A
SURFACE LOW AS IT LIFTS NORTHWARD FROM THE SOUTHERN PLAINS TO
NORTHERN LOWER MICHIGAN SUNDAY MORNING TO MONDAY MORNING. WE REMAIN
ON THE WARM SIDE OF THE SYSTEM WITH A GOOD FEED OF MOISTURE SO A
RAINY PERIOD CAN BE EXPECTED...WITH THE HIGHEST POPS CENTERED ON
LATE SUNDAY TO EARLY MONDAY. SOME DISAGREEMENT EXISTS ON HOW FAST
THE UPPER WAVE AND ATTENDANT SURFACE LOW AND FORCING LIFT IN SUNDAY
SO THE DAY MAY NOT BE A COMPLETE WASHOUT...BUT WILL REFINE TIMING
WITH FUTURE FORECASTS. THE COLD FRONT MOVES THROUGH LATER MONDAY
USHERING A COLDER AIRMASS BACK IN SO THE WARMING TREND LOOKS TO BE
SHORT LIVED.

MARINE...

NORTHWEST WINDS GUSTING TO GALES WILL GRADUALLY EASE THROUGH TONIGHT
AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES. ALL GALE WARNINGS AND
SMALL CRAFT ADVISORIES ARE THEREFORE SCHEDULED TO EXPIRE
INCREMENTALLY THROUGH THE NIGHT AS WINDS AND WAVES SUBSIDE. A
MODERATE SOUTHWEST BREEZE WILL THEN DOMINATE THROUGH FRIDAY BEFORE
DEPARTURE OF HIGH PRESSURE TO THE EAST TRIGGERS AN INCREASE IN WINDS
AGAIN ON FRIDAY NIGHT. SOUTHWESTERLY GUSTS TO GALES OR NEAR GALES
WILL BE POSSIBLE FRIDAY NIGHT THROUGH THE FIRST HALF OF
SATURDAY...MAINLY OVER THE CENTRAL SW TO NE AXIS OF LAKE HURON.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WARNING UNTIL 3 AM EST FRIDAY FOR LHZ362-363-462-463.

     SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR LHZ421-441>443.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...LOW WATER ADVISORY UNTIL 4 AM EST FRIDAY FOR LEZ444.

&&

$$

AVIATION.....KURIMSKI
SHORT TERM...SC
LONG TERM....JVC/DT
MARINE.......JVC


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 210449
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1149 PM EST THU NOV 20 2014


.AVIATION...

//DISCUSSION...

LAKE EFFECT SNOW SHOWERS HAVE ALL BUT ENDED FOR THE TAF SITES
OVERNIGHT...WITH THE LONE EXCEPTION BEING YIP WHERE SOME LINGERING
FLURRIES AND VERY LIGHT SNOW CONTINUES. OUTSIDE OF THIS MOST TAF
SITES HAVE CLEARED OR HAVE RISEN TO VFR.  THIS IS EXPECTED TO
CONTINUE THROUGHT DAYTIME HOURS ON FRIDAY AND INTO FRIDAY NIGHT AS A
RIDGE OF HIGH PRESSURE TRACKS THROUGH THE CENTRAL GREAT LAKES.

//DTW THRESHOLD THREATS...

* NONE.

&&

.PREV DISCUSSION...ISSUED DETROIT/PONTIAC MI 319 PM EST THU NOV 20 2014

SHORT TERM...THIS EVENING AND TONIGHT

THE ONGOING SNOW SHOWERS ACROSS PORTIONS OF THE FORECAST AREA HAVE
BEEN THE RESULT OF LAKE EFFECT OFF LAKE MI...SUSTAINED THIS FAR EAST
BY STRONG WSW FLOW WITHIN AN ENHANCED W-E BOUNDARY LAYER CONVERGENCE
AXIS. CONVECTIVE UPDRAFTS HAVE BEEN WITHIN THE GOOD DENDRITIC GROWTH
LAYER...SO FLAKE SIZE HAS BEEN RESPECTABLE. A LONGER LIVED HEAVY BAND
OF SNOW IMPACTED LOCATIONS ALONG AN AXIS FROM SRN SHIAWASSEE/SRN
GENESEE/NRN OAKLAND COUNTIES INTO THE PORT HURON AREA EARLIER TODAY.
SPOTTER REPORTS SUGGEST A SOLID 3 TO 5 INCHES FELL IN THESE AREAS.
WHILE ACCUMULATIONS HAVE BEEN MUCH LESS OUTSIDE OF THIS REGION...THE
INTENSE SNOW SHOWERS HAVE STILL BEEN LEADING TO SPORADIC REDUCTIONS
IN VISIBILITIES AND A QUICK DUSTING OF ACCUMULATION. WINDS HAVE ALSO
INCREASED THIS AFTERNOON /WITH SOME GUSTS OVER 30 MPH REPORTED/
WHICH HAS BEEN CAUSING SOME BLOWING SNOW AND MINOR DRIFTING IN THE
ADVISORY AREA.

ONGOING MID LEVEL COLD AIR ADVECTION AND DAYTIME HEATING HAS BEEN
LIFTING CONVECTIVE DEPTHS THIS AFTERNOON. THIS HAS ACTUALLY RESULTED
IN SOME DISRUPTION TO THE MORE ORGANIZED BANDING. DEEPER MIXING HAS
ALSO LED TO A MORE UNIFORM WESTERLY SURFACE WIND ACROSS SRN
MI...WEAKENING THE CONVERGENCE IN THE BOUNDARY LAYER. THE PREVAILING
WESTERLY FLOW WILL STILL FOCUS THE MORE WIDESPREAD SNOW SHOWER
ACTIVITY ACROSS THE ADVISORY AREA THROUGH EVENING RUSH HOUR. VEERING
OF THE LOW LEVEL FLOW TOWARD THE NORTHWEST DURING THE COURSE OF THE
NIGHT WILL FOCUS THE MORE NUMEROUS SNOW SHOWERS SOUTH OF THE I-
96/696 CORRIDOR LATER THIS EVENING. THERE WILL BE AN OVERALL
WEAKENING TREND TO LAKE EFFECT DURING THE NIGHT UNDER CONTINUED LOW
LEVEL DRY AIR ADVECTION AND LOWERING CONVECTIVE DEPTHS AS A RESULT
OF INCREASING LARGE SCALE SUBSIDENCE. THIS WILL DIMINISH THE OVERALL
COVERAGE OF SNOW SHOWERS. A TRANSITION TOWARD MORE DOMINATE BANDING
IS POSSIBLE PRIOR TO DAYBREAK...WHICH MAY IMPACT FAR SOUTHERN
COUNTIES LATER TONIGHT. THIS IS A FAIRLY LOW CONFIDENCE
SCENARIO...SUGGESTING HOLDING JUST MINOR ADDITIONAL ACCUMULATIONS
TONIGHT ATTM. THE VEERING OF THE FLOW TOWARD THE NORTHWEST AND LOW
LEVEL DRY AIR ADVECTION WILL LEAD TO SOME CLEARING DURING THE COURSE
OF THE NIGHT /ESPECIALLY ACROSS THE SAGINAW VALLEY AND THUMB/. THIS
AND A GRADUAL WEAKENING GRADIENT WILL OFFER AN OPPORTUNITY FOR GOOD
RADIATIONAL COOLING /SUPPORTING MIN TEMPS IN THE SINGLE DIGITS TO
LOWER TEENS/.

LONG TERM...

THE SURGE OF STRONG PACIFIC ENERGY TAKING AIM ON THE PACIFIC
NORTHWEST OVER THE NEXT 24 HOURS HAS DEAMPLIFIED THE WEST COAST
RIDGE RESULTING IN A TRANSITION TO ZONAL FLOW ACROSS THE CONUS. THE
ZONAL REGIME WILL SPREAD INTO THE GREAT LAKES, FLOODING THE MID-
LEVELS WITH WARMER AIR, UPON THE DEPARTURE OF TODAY`S TROUGH.
BETWEEN 12Z FRIDAY AND 12Z SATURDAY, H85 TEMPERATURES OVER SOUTHEAST
MICHIGAN WILL RISE ABOUT 20 DEGREES AS THE MID-LEVEL CLIMB ABOVE
FREEZING BY SATURDAY MORNING. SHORTWAVE RIDGING EMBEDDED IN THE
DEVELOPING ZONAL FLOW WILL BUILD INTO THE AREA DURING THE DAY FRIDAY
AND EASE THE SURFACE HIGH OVER THE OHIO VALLEY EAST. RETURN FLOW AT
THE SURFACE WILL BE OF LITTLE HELP WITH ARCTIC AIR ENTRENCHED OVER
THE EASTERN US. TEMPERATURES WILL REMAIN IN THE UPPER TEENS/LOW 20S
TOMORROW THROUGH TOMORROW NIGHT. AS A RESULT, A STRONG INVERSION
WILL BEGIN TO TAKE SHAPE ON FRIDAY NIGHT AS THE SHORTWAVE OVER THE
INTERMOUNTAIN WEST EJECTS OUT OVER THE GREAT LAKES. ISENTROPIC
ASCENT AND A QUICK HIT OF PV ADVECTION 09Z-15Z SATURDAY MORNING WILL
SUPPORT AT LEAST A SCATTERED COVERAGE OF SHOWERS LIFTING THROUGH THE
AREA. CURRENT INDICATIONS ARE THAT THIS PRECIPITATION MAY FALL AS
FREEZING RAIN. SHORT DURATION AND LACK OF MAINTENANCE FOR SUB-ZERO
WET BULBING AT THE SURFACE LIMIT CONCERNS, BUT THE POTENTIAL FOR
SOME LIGHT ICING IS EVIDENT.

WEAK ISENTROPIC ASCENT WILL THEN BE ONGOING THROUGH THE DAY SATURDAY
AS A 100KT JET DEVELOPS OVERHEAD IN RESPONSE TO THE DEEPENING LONGWAVE
TROUGH UPSTREAM. THIS WILL HELP ORIENT A MID-LEVEL BAROCLINIC ZONE
ACROSS THE AREA WHICH WILL SERVE AS A FOCUS FOR ONGOING
PRECIPITATION DURING THE DAY. DRY MID-LEVELS SUGGEST THAT DRIZZLE,
AS OPPOSED TO SHOWERS, WILL BE WORTH KEEPING AN EYE ON. EITHER WAY,
TEMPERATURE RECOVERY DURING THIS TIME WILL BE IMPORTANT TO WATCH AS
AN ADDITIONAL FREEZING PRECIP THREAT COULD THEORETICALLY EVOLVE.
HOWEVER, THE SOLID SOUTHERLY GRADIENT COMBINED WITH THE NAM`S
TENDENCY TO HOLD ONTO LOW-LEVEL COLD AIR A BIT TOO LONG HELP
ALLEVIATE THAT CONCERN AT THIS TIME.

GLOBAL NWP REMAINS IN DECENT AGREEMENT WITH THE REST OF THE
FORECAST WITH SLIGHT DIFFERENCES IN TIMING AND LOCATION OF A
SURFACE LOW AS IT LIFTS NORTHWARD FROM THE SOUTHERN PLAINS TO
NORTHERN LOWER MICHIGAN SUNDAY MORNING TO MONDAY MORNING. WE REMAIN
ON THE WARM SIDE OF THE SYSTEM WITH A GOOD FEED OF MOISTURE SO A
RAINY PERIOD CAN BE EXPECTED...WITH THE HIGHEST POPS CENTERED ON
LATE SUNDAY TO EARLY MONDAY. SOME DISAGREEMENT EXISTS ON HOW FAST
THE UPPER WAVE AND ATTENDANT SURFACE LOW AND FORCING LIFT IN SUNDAY
SO THE DAY MAY NOT BE A COMPLETE WASHOUT...BUT WILL REFINE TIMING
WITH FUTURE FORECASTS. THE COLD FRONT MOVES THROUGH LATER MONDAY
USHERING A COLDER AIRMASS BACK IN SO THE WARMING TREND LOOKS TO BE
SHORT LIVED.

MARINE...

NORTHWEST WINDS GUSTING TO GALES WILL GRADUALLY EASE THROUGH TONIGHT
AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES. ALL GALE WARNINGS AND
SMALL CRAFT ADVISORIES ARE THEREFORE SCHEDULED TO EXPIRE
INCREMENTALLY THROUGH THE NIGHT AS WINDS AND WAVES SUBSIDE. A
MODERATE SOUTHWEST BREEZE WILL THEN DOMINATE THROUGH FRIDAY BEFORE
DEPARTURE OF HIGH PRESSURE TO THE EAST TRIGGERS AN INCREASE IN WINDS
AGAIN ON FRIDAY NIGHT. SOUTHWESTERLY GUSTS TO GALES OR NEAR GALES
WILL BE POSSIBLE FRIDAY NIGHT THROUGH THE FIRST HALF OF
SATURDAY...MAINLY OVER THE CENTRAL SW TO NE AXIS OF LAKE HURON.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WARNING UNTIL 3 AM EST FRIDAY FOR LHZ362-363-462-463.

     SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR LHZ421-441>443.

LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...LOW WATER ADVISORY UNTIL 4 AM EST FRIDAY FOR LEZ444.

&&

$$

AVIATION.....KURIMSKI
SHORT TERM...SC
LONG TERM....JVC/DT
MARINE.......JVC


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 202314
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
614 PM EST THU NOV 20 2014


.AVIATION...

//DISCUSSION...

LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO WORK THROUGH SOUTHEAST
MICHIGAN DURING THE EVENING HOURS...SINKING SOUTH AND DISSIPATING AS
THE FLOW BECOMES LIGHTER AND MORE STABLE AIR ADVECTS IN. THE SNOW
WILL MAINLY AFFECT THE AIRPORTS FROM PTK SOUTH TO THE METRO
AIRPORTS...DISSIPATING AROUND MIDNIGHT. THE MOST INTENSE SNOW BANDS
APPEAR TO HAVE ENDED AS THEY LOSE THE FEED OF MOISTURE FROM LAKE
MICHIGAN...WITH MVFR AND POSSIBLE IFR CONDITIONS EXPECTED THIS
EVENING IN HEAVIER SNOW SHOWERS. SOME CLEARING IS THEN EXPECTED FROM
NORTH TO SOUTH AS DRIER AIR ADVECTS IN...WITH CLEARING ALREADY NOTED
AT MBS AND FNT. HIGH PRESSURE WILL KEEP CONDITIONS DRY ON FRIDAY
WITH VFR CONDITIONS EXPECTED DURING THE DAYTIME HOURS.

FOR DTW...THROUGH THE EVENING...THE MORE WIDESPREAD AND INTENSE SNOW
SHOWERS SHOULD REMAIN NORTH AND EAST OF METRO. LAKE EFFECT HEADING
SOUTH MAY BRING SOME OF THE MODERATE INTENSITY SNOW SHOWERS INTO
METRO...POSSIBLY LEADING TO SOME MINOR ACCUMULATIONS. CONTINUED
VEERING OF THE WINDS OVERNIGHT SHOULD PUSH LINGERING SNOW SHOWERS
SOUTH OF METRO AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5KFT THIS EVENING...RISING ABOVE
  5KFT BY MIDNIGHT.

* LOW CONFIDENCE IN BRIEF INTERVALS OF VISIBILITY BELOW A HALF MILE
  IN SNOW THIS EVENING.

&&

.PREV DISCUSSION...ISSUED DETROIT/PONTIAC MI 319 PM EST THU NOV 20 2014

SHORT TERM...THIS EVENING AND TONIGHT

THE ONGOING SNOW SHOWERS ACROSS PORTIONS OF THE FORECAST AREA HAVE
BEEN THE RESULT OF LAKE EFFECT OFF LAKE MI...SUSTAINED THIS FAR EAST
BY STRONG WSW FLOW WITHIN AN ENHANCED W-E BOUNDARY LAYER CONVERGENCE
AXIS. CONVECTIVE UPDRAFTS HAVE BEEN WITHIN THE GOOD DENDRITIC GROWTH
LAYER...SO FLAKE SIZE HAS BEEN RESPECTABLE. A LONGER LIVED HEAVY BAND
OF SNOW IMPACTED LOCATIONS ALONG AN AXIS FROM SRN SHIAWASSEE/SRN
GENESEE/NRN OAKLAND COUNTIES INTO THE PORT HURON AREA EARLIER TODAY.
SPOTTER REPORTS SUGGEST A SOLID 3 TO 5 INCHES FELL IN THESE AREAS.
WHILE ACCUMULATIONS HAVE BEEN MUCH LESS OUTSIDE OF THIS REGION...THE
INTENSE SNOW SHOWERS HAVE STILL BEEN LEADING TO SPORADIC REDUCTIONS
IN VISIBILITIES AND A QUICK DUSTING OF ACCUMULATION. WINDS HAVE ALSO
INCREASED THIS AFTERNOON /WITH SOME GUSTS OVER 30 MPH REPORTED/
WHICH HAS BEEN CAUSING SOME BLOWING SNOW AND MINOR DRIFTING IN THE
ADVISORY AREA.

ONGOING MID LEVEL COLD AIR ADVECTION AND DAYTIME HEATING HAS BEEN
LIFTING CONVECTIVE DEPTHS THIS AFTERNOON. THIS HAS ACTUALLY RESULTED
IN SOME DISRUPTION TO THE MORE ORGANIZED BANDING. DEEPER MIXING HAS
ALSO LED TO A MORE UNIFORM WESTERLY SURFACE WIND ACROSS SRN
MI...WEAKENING THE CONVERGENCE IN THE BOUNDARY LAYER. THE PREVAILING
WESTERLY FLOW WILL STILL FOCUS THE MORE WIDESPREAD SNOW SHOWER
ACTIVITY ACROSS THE ADVISORY AREA THROUGH EVENING RUSH HOUR. VEERING
OF THE LOW LEVEL FLOW TOWARD THE NORTHWEST DURING THE COURSE OF THE
NIGHT WILL FOCUS THE MORE NUMEROUS SNOW SHOWERS SOUTH OF THE I-
96/696 CORRIDOR LATER THIS EVENING. THERE WILL BE AN OVERALL
WEAKENING TREND TO LAKE EFFECT DURING THE NIGHT UNDER CONTINUED LOW
LEVEL DRY AIR ADVECTION AND LOWERING CONVECTIVE DEPTHS AS A RESULT
OF INCREASING LARGE SCALE SUBSIDENCE. THIS WILL DIMINISH THE OVERALL
COVERAGE OF SNOW SHOWERS. A TRANSITION TOWARD MORE DOMINATE BANDING
IS POSSIBLE PRIOR TO DAYBREAK...WHICH MAY IMPACT FAR SOUTHERN
COUNTIES LATER TONIGHT. THIS IS A FAIRLY LOW CONFIDENCE
SCENARIO...SUGGESTING HOLDING JUST MINOR ADDITIONAL ACCUMULATIONS
TONIGHT ATTM. THE VEERING OF THE FLOW TOWARD THE NORTHWEST AND LOW
LEVEL DRY AIR ADVECTION WILL LEAD TO SOME CLEARING DURING THE COURSE
OF THE NIGHT /ESPECIALLY ACROSS THE SAGINAW VALLEY AND THUMB/. THIS
AND A GRADUAL WEAKENING GRADIENT WILL OFFER AN OPPORTUNITY FOR GOOD
RADIATIONAL COOLING /SUPPORTING MIN TEMPS IN THE SINGLE DIGITS TO
LOWER TEENS/.

LONG TERM...

THE SURGE OF STRONG PACIFIC ENERGY TAKING AIM ON THE PACIFIC
NORTHWEST OVER THE NEXT 24 HOURS HAS DEAMPLIFIED THE WEST COAST
RIDGE RESULTING IN A TRANSITION TO ZONAL FLOW ACROSS THE CONUS. THE
ZONAL REGIME WILL SPREAD INTO THE GREAT LAKES, FLOODING THE MID-
LEVELS WITH WARMER AIR, UPON THE DEPARTURE OF TODAY`S TROUGH.
BETWEEN 12Z FRIDAY AND 12Z SATURDAY, H85 TEMPERATURES OVER SOUTHEAST
MICHIGAN WILL RISE ABOUT 20 DEGREES AS THE MID-LEVEL CLIMB ABOVE
FREEZING BY SATURDAY MORNING. SHORTWAVE RIDGING EMBEDDED IN THE
DEVELOPING ZONAL FLOW WILL BUILD INTO THE AREA DURING THE DAY FRIDAY
AND EASE THE SURFACE HIGH OVER THE OHIO VALLEY EAST. RETURN FLOW AT
THE SURFACE WILL BE OF LITTLE HELP WITH ARCTIC AIR ENTRENCHED OVER
THE EASTERN US. TEMPERATURES WILL REMAIN IN THE UPPER TEENS/LOW 20S
TOMORROW THROUGH TOMORROW NIGHT. AS A RESULT, A STRONG INVERSION
WILL BEGIN TO TAKE SHAPE ON FRIDAY NIGHT AS THE SHORTWAVE OVER THE
INTERMOUNTAIN WEST EJECTS OUT OVER THE GREAT LAKES. ISENTROPIC
ASCENT AND A QUICK HIT OF PV ADVECTION 09Z-15Z SATURDAY MORNING WILL
SUPPORT AT LEAST A SCATTERED COVERAGE OF SHOWERS LIFTING THROUGH THE
AREA. CURRENT INDICATIONS ARE THAT THIS PRECIPITATION MAY FALL AS
FREEZING RAIN. SHORT DURATION AND LACK OF MAINTENANCE FOR SUB-ZERO
WET BULBING AT THE SURFACE LIMIT CONCERNS, BUT THE POTENTIAL FOR
SOME LIGHT ICING IS EVIDENT.

WEAK ISENTROPIC ASCENT WILL THEN BE ONGOING THROUGH THE DAY SATURDAY
AS A 100KT JET DEVELOPS OVERHEAD IN RESPONSE TO THE DEEPENING LONGWAVE
TROUGH UPSTREAM. THIS WILL HELP ORIENT A MID-LEVEL BAROCLINIC ZONE
ACROSS THE AREA WHICH WILL SERVE AS A FOCUS FOR ONGOING
PRECIPITATION DURING THE DAY. DRY MID-LEVELS SUGGEST THAT DRIZZLE,
AS OPPOSED TO SHOWERS, WILL BE WORTH KEEPING AN EYE ON. EITHER WAY,
TEMPERATURE RECOVERY DURING THIS TIME WILL BE IMPORTANT TO WATCH AS
AN ADDITIONAL FREEZING PRECIP THREAT COULD THEORETICALLY EVOLVE.
HOWEVER, THE SOLID SOUTHERLY GRADIENT COMBINED WITH THE NAM`S
TENDENCY TO HOLD ONTO LOW-LEVEL COLD AIR A BIT TOO LONG HELP
ALLEVIATE THAT CONCERN AT THIS TIME.

GLOBAL NWP REMAINS IN DECENT AGREEMENT WITH THE REST OF THE
FORECAST WITH SLIGHT DIFFERENCES IN TIMING AND LOCATION OF A
SURFACE LOW AS IT LIFTS NORTHWARD FROM THE SOUTHERN PLAINS TO
NORTHERN LOWER MICHIGAN SUNDAY MORNING TO MONDAY MORNING. WE REMAIN
ON THE WARM SIDE OF THE SYSTEM WITH A GOOD FEED OF MOISTURE SO A
RAINY PERIOD CAN BE EXPECTED...WITH THE HIGHEST POPS CENTERED ON
LATE SUNDAY TO EARLY MONDAY. SOME DISAGREEMENT EXISTS ON HOW FAST
THE UPPER WAVE AND ATTENDANT SURFACE LOW AND FORCING LIFT IN SUNDAY
SO THE DAY MAY NOT BE A COMPLETE WASHOUT...BUT WILL REFINE TIMING
WITH FUTURE FORECASTS. THE COLD FRONT MOVES THROUGH LATER MONDAY
USHERING A COLDER AIRMASS BACK IN SO THE WARMING TREND LOOKS TO BE
SHORT LIVED.

MARINE...

NORTHWEST WINDS GUSTING TO GALES WILL GRADUALLY EASE THROUGH TONIGHT
AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES. ALL GALE WARNINGS AND
SMALL CRAFT ADVISORIES ARE THEREFORE SCHEDULED TO EXPIRE
INCREMENTALLY THROUGH THE NIGHT AS WINDS AND WAVES SUBSIDE. A
MODERATE SOUTHWEST BREEZE WILL THEN DOMINATE THROUGH FRIDAY BEFORE
DEPARTURE OF HIGH PRESSURE TO THE EAST TRIGGERS AN INCREASE IN WINDS
AGAIN ON FRIDAY NIGHT. SOUTHWESTERLY GUSTS TO GALES OR NEAR GALES
WILL BE POSSIBLE FRIDAY NIGHT THROUGH THE FIRST HALF OF
SATURDAY...MAINLY OVER THE CENTRAL SW TO NE AXIS OF LAKE HURON.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ063-
     068>070.

LAKE HURON...GALE WARNING UNTIL 3 AM EST FRIDAY FOR LHZ362-363-462-463.

     SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR LHZ421-441>443.

     GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LHZ361.

LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LEZ444.

     LOW WATER ADVISORY UNTIL 4 AM EST FRIDAY FOR LEZ444.

&&

$$

AVIATION.....KURIMSKI
SHORT TERM...SC
LONG TERM....JVC/DT
MARINE.......JVC


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 202314
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
614 PM EST THU NOV 20 2014


.AVIATION...

//DISCUSSION...

LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO WORK THROUGH SOUTHEAST
MICHIGAN DURING THE EVENING HOURS...SINKING SOUTH AND DISSIPATING AS
THE FLOW BECOMES LIGHTER AND MORE STABLE AIR ADVECTS IN. THE SNOW
WILL MAINLY AFFECT THE AIRPORTS FROM PTK SOUTH TO THE METRO
AIRPORTS...DISSIPATING AROUND MIDNIGHT. THE MOST INTENSE SNOW BANDS
APPEAR TO HAVE ENDED AS THEY LOSE THE FEED OF MOISTURE FROM LAKE
MICHIGAN...WITH MVFR AND POSSIBLE IFR CONDITIONS EXPECTED THIS
EVENING IN HEAVIER SNOW SHOWERS. SOME CLEARING IS THEN EXPECTED FROM
NORTH TO SOUTH AS DRIER AIR ADVECTS IN...WITH CLEARING ALREADY NOTED
AT MBS AND FNT. HIGH PRESSURE WILL KEEP CONDITIONS DRY ON FRIDAY
WITH VFR CONDITIONS EXPECTED DURING THE DAYTIME HOURS.

FOR DTW...THROUGH THE EVENING...THE MORE WIDESPREAD AND INTENSE SNOW
SHOWERS SHOULD REMAIN NORTH AND EAST OF METRO. LAKE EFFECT HEADING
SOUTH MAY BRING SOME OF THE MODERATE INTENSITY SNOW SHOWERS INTO
METRO...POSSIBLY LEADING TO SOME MINOR ACCUMULATIONS. CONTINUED
VEERING OF THE WINDS OVERNIGHT SHOULD PUSH LINGERING SNOW SHOWERS
SOUTH OF METRO AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5KFT THIS EVENING...RISING ABOVE
  5KFT BY MIDNIGHT.

* LOW CONFIDENCE IN BRIEF INTERVALS OF VISIBILITY BELOW A HALF MILE
  IN SNOW THIS EVENING.

&&

.PREV DISCUSSION...ISSUED DETROIT/PONTIAC MI 319 PM EST THU NOV 20 2014

SHORT TERM...THIS EVENING AND TONIGHT

THE ONGOING SNOW SHOWERS ACROSS PORTIONS OF THE FORECAST AREA HAVE
BEEN THE RESULT OF LAKE EFFECT OFF LAKE MI...SUSTAINED THIS FAR EAST
BY STRONG WSW FLOW WITHIN AN ENHANCED W-E BOUNDARY LAYER CONVERGENCE
AXIS. CONVECTIVE UPDRAFTS HAVE BEEN WITHIN THE GOOD DENDRITIC GROWTH
LAYER...SO FLAKE SIZE HAS BEEN RESPECTABLE. A LONGER LIVED HEAVY BAND
OF SNOW IMPACTED LOCATIONS ALONG AN AXIS FROM SRN SHIAWASSEE/SRN
GENESEE/NRN OAKLAND COUNTIES INTO THE PORT HURON AREA EARLIER TODAY.
SPOTTER REPORTS SUGGEST A SOLID 3 TO 5 INCHES FELL IN THESE AREAS.
WHILE ACCUMULATIONS HAVE BEEN MUCH LESS OUTSIDE OF THIS REGION...THE
INTENSE SNOW SHOWERS HAVE STILL BEEN LEADING TO SPORADIC REDUCTIONS
IN VISIBILITIES AND A QUICK DUSTING OF ACCUMULATION. WINDS HAVE ALSO
INCREASED THIS AFTERNOON /WITH SOME GUSTS OVER 30 MPH REPORTED/
WHICH HAS BEEN CAUSING SOME BLOWING SNOW AND MINOR DRIFTING IN THE
ADVISORY AREA.

ONGOING MID LEVEL COLD AIR ADVECTION AND DAYTIME HEATING HAS BEEN
LIFTING CONVECTIVE DEPTHS THIS AFTERNOON. THIS HAS ACTUALLY RESULTED
IN SOME DISRUPTION TO THE MORE ORGANIZED BANDING. DEEPER MIXING HAS
ALSO LED TO A MORE UNIFORM WESTERLY SURFACE WIND ACROSS SRN
MI...WEAKENING THE CONVERGENCE IN THE BOUNDARY LAYER. THE PREVAILING
WESTERLY FLOW WILL STILL FOCUS THE MORE WIDESPREAD SNOW SHOWER
ACTIVITY ACROSS THE ADVISORY AREA THROUGH EVENING RUSH HOUR. VEERING
OF THE LOW LEVEL FLOW TOWARD THE NORTHWEST DURING THE COURSE OF THE
NIGHT WILL FOCUS THE MORE NUMEROUS SNOW SHOWERS SOUTH OF THE I-
96/696 CORRIDOR LATER THIS EVENING. THERE WILL BE AN OVERALL
WEAKENING TREND TO LAKE EFFECT DURING THE NIGHT UNDER CONTINUED LOW
LEVEL DRY AIR ADVECTION AND LOWERING CONVECTIVE DEPTHS AS A RESULT
OF INCREASING LARGE SCALE SUBSIDENCE. THIS WILL DIMINISH THE OVERALL
COVERAGE OF SNOW SHOWERS. A TRANSITION TOWARD MORE DOMINATE BANDING
IS POSSIBLE PRIOR TO DAYBREAK...WHICH MAY IMPACT FAR SOUTHERN
COUNTIES LATER TONIGHT. THIS IS A FAIRLY LOW CONFIDENCE
SCENARIO...SUGGESTING HOLDING JUST MINOR ADDITIONAL ACCUMULATIONS
TONIGHT ATTM. THE VEERING OF THE FLOW TOWARD THE NORTHWEST AND LOW
LEVEL DRY AIR ADVECTION WILL LEAD TO SOME CLEARING DURING THE COURSE
OF THE NIGHT /ESPECIALLY ACROSS THE SAGINAW VALLEY AND THUMB/. THIS
AND A GRADUAL WEAKENING GRADIENT WILL OFFER AN OPPORTUNITY FOR GOOD
RADIATIONAL COOLING /SUPPORTING MIN TEMPS IN THE SINGLE DIGITS TO
LOWER TEENS/.

LONG TERM...

THE SURGE OF STRONG PACIFIC ENERGY TAKING AIM ON THE PACIFIC
NORTHWEST OVER THE NEXT 24 HOURS HAS DEAMPLIFIED THE WEST COAST
RIDGE RESULTING IN A TRANSITION TO ZONAL FLOW ACROSS THE CONUS. THE
ZONAL REGIME WILL SPREAD INTO THE GREAT LAKES, FLOODING THE MID-
LEVELS WITH WARMER AIR, UPON THE DEPARTURE OF TODAY`S TROUGH.
BETWEEN 12Z FRIDAY AND 12Z SATURDAY, H85 TEMPERATURES OVER SOUTHEAST
MICHIGAN WILL RISE ABOUT 20 DEGREES AS THE MID-LEVEL CLIMB ABOVE
FREEZING BY SATURDAY MORNING. SHORTWAVE RIDGING EMBEDDED IN THE
DEVELOPING ZONAL FLOW WILL BUILD INTO THE AREA DURING THE DAY FRIDAY
AND EASE THE SURFACE HIGH OVER THE OHIO VALLEY EAST. RETURN FLOW AT
THE SURFACE WILL BE OF LITTLE HELP WITH ARCTIC AIR ENTRENCHED OVER
THE EASTERN US. TEMPERATURES WILL REMAIN IN THE UPPER TEENS/LOW 20S
TOMORROW THROUGH TOMORROW NIGHT. AS A RESULT, A STRONG INVERSION
WILL BEGIN TO TAKE SHAPE ON FRIDAY NIGHT AS THE SHORTWAVE OVER THE
INTERMOUNTAIN WEST EJECTS OUT OVER THE GREAT LAKES. ISENTROPIC
ASCENT AND A QUICK HIT OF PV ADVECTION 09Z-15Z SATURDAY MORNING WILL
SUPPORT AT LEAST A SCATTERED COVERAGE OF SHOWERS LIFTING THROUGH THE
AREA. CURRENT INDICATIONS ARE THAT THIS PRECIPITATION MAY FALL AS
FREEZING RAIN. SHORT DURATION AND LACK OF MAINTENANCE FOR SUB-ZERO
WET BULBING AT THE SURFACE LIMIT CONCERNS, BUT THE POTENTIAL FOR
SOME LIGHT ICING IS EVIDENT.

WEAK ISENTROPIC ASCENT WILL THEN BE ONGOING THROUGH THE DAY SATURDAY
AS A 100KT JET DEVELOPS OVERHEAD IN RESPONSE TO THE DEEPENING LONGWAVE
TROUGH UPSTREAM. THIS WILL HELP ORIENT A MID-LEVEL BAROCLINIC ZONE
ACROSS THE AREA WHICH WILL SERVE AS A FOCUS FOR ONGOING
PRECIPITATION DURING THE DAY. DRY MID-LEVELS SUGGEST THAT DRIZZLE,
AS OPPOSED TO SHOWERS, WILL BE WORTH KEEPING AN EYE ON. EITHER WAY,
TEMPERATURE RECOVERY DURING THIS TIME WILL BE IMPORTANT TO WATCH AS
AN ADDITIONAL FREEZING PRECIP THREAT COULD THEORETICALLY EVOLVE.
HOWEVER, THE SOLID SOUTHERLY GRADIENT COMBINED WITH THE NAM`S
TENDENCY TO HOLD ONTO LOW-LEVEL COLD AIR A BIT TOO LONG HELP
ALLEVIATE THAT CONCERN AT THIS TIME.

GLOBAL NWP REMAINS IN DECENT AGREEMENT WITH THE REST OF THE
FORECAST WITH SLIGHT DIFFERENCES IN TIMING AND LOCATION OF A
SURFACE LOW AS IT LIFTS NORTHWARD FROM THE SOUTHERN PLAINS TO
NORTHERN LOWER MICHIGAN SUNDAY MORNING TO MONDAY MORNING. WE REMAIN
ON THE WARM SIDE OF THE SYSTEM WITH A GOOD FEED OF MOISTURE SO A
RAINY PERIOD CAN BE EXPECTED...WITH THE HIGHEST POPS CENTERED ON
LATE SUNDAY TO EARLY MONDAY. SOME DISAGREEMENT EXISTS ON HOW FAST
THE UPPER WAVE AND ATTENDANT SURFACE LOW AND FORCING LIFT IN SUNDAY
SO THE DAY MAY NOT BE A COMPLETE WASHOUT...BUT WILL REFINE TIMING
WITH FUTURE FORECASTS. THE COLD FRONT MOVES THROUGH LATER MONDAY
USHERING A COLDER AIRMASS BACK IN SO THE WARMING TREND LOOKS TO BE
SHORT LIVED.

MARINE...

NORTHWEST WINDS GUSTING TO GALES WILL GRADUALLY EASE THROUGH TONIGHT
AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES. ALL GALE WARNINGS AND
SMALL CRAFT ADVISORIES ARE THEREFORE SCHEDULED TO EXPIRE
INCREMENTALLY THROUGH THE NIGHT AS WINDS AND WAVES SUBSIDE. A
MODERATE SOUTHWEST BREEZE WILL THEN DOMINATE THROUGH FRIDAY BEFORE
DEPARTURE OF HIGH PRESSURE TO THE EAST TRIGGERS AN INCREASE IN WINDS
AGAIN ON FRIDAY NIGHT. SOUTHWESTERLY GUSTS TO GALES OR NEAR GALES
WILL BE POSSIBLE FRIDAY NIGHT THROUGH THE FIRST HALF OF
SATURDAY...MAINLY OVER THE CENTRAL SW TO NE AXIS OF LAKE HURON.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ063-
     068>070.

LAKE HURON...GALE WARNING UNTIL 3 AM EST FRIDAY FOR LHZ362-363-462-463.

     SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR LHZ421-441>443.

     GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LHZ361.

LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LEZ444.

     LOW WATER ADVISORY UNTIL 4 AM EST FRIDAY FOR LEZ444.

&&

$$

AVIATION.....KURIMSKI
SHORT TERM...SC
LONG TERM....JVC/DT
MARINE.......JVC


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 202019
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
319 PM EST THU NOV 20 2014

.SHORT TERM...THIS EVENING AND TONIGHT

THE ONGOING SNOW SHOWERS ACROSS PORTIONS OF THE FORECAST AREA HAVE
BEEN THE RESULT OF LAKE EFFECT OFF LAKE MI...SUSTAINED THIS FAR EAST
BY STRONG WSW FLOW WITHIN AN ENHANCED W-E BOUNDARY LAYER CONVERGENCE
AXIS. CONVECTIVE UPDRAFTS HAVE BEEN WITHIN THE GOOD DENDRITIC GROWTH
LAYER...SO FLAKE SIZE HAS BEEN RESPECTABLE. A LONGER LIVED HEAVY BAND
OF SNOW IMPACTED LOCATIONS ALONG AN AXIS FROM SRN SHIAWASSEE/SRN
GENESEE/NRN OAKLAND COUNTIES INTO THE PORT HURON AREA EARLIER TODAY.
SPOTTER REPORTS SUGGEST A SOLID 3 TO 5 INCHES FELL IN THESE AREAS.
WHILE ACCUMULATIONS HAVE BEEN MUCH LESS OUTSIDE OF THIS REGION...THE
INTENSE SNOW SHOWERS HAVE STILL BEEN LEADING TO SPORADIC REDUCTIONS
IN VISIBILITIES AND A QUICK DUSTING OF ACCUMULATION. WINDS HAVE ALSO
INCREASED THIS AFTERNOON /WITH SOME GUSTS OVER 30 MPH REPORTED/
WHICH HAS BEEN CAUSING SOME BLOWING SNOW AND MINOR DRIFTING IN THE
ADVISORY AREA.

ONGOING MID LEVEL COLD AIR ADVECTION AND DAYTIME HEATING HAS BEEN
LIFTING CONVECTIVE DEPTHS THIS AFTERNOON. THIS HAS ACTUALLY RESULTED
IN SOME DISRUPTION TO THE MORE ORGANIZED BANDING. DEEPER MIXING HAS
ALSO LED TO A MORE UNIFORM WESTERLY SURFACE WIND ACROSS SRN
MI...WEAKENING THE CONVERGENCE IN THE BOUNDARY LAYER. THE PREVAILING
WESTERLY FLOW WILL STILL FOCUS THE MORE WIDESPREAD SNOW SHOWER
ACTIVITY ACROSS THE ADVISORY AREA THROUGH EVENING RUSH HOUR. VEERING
OF THE LOW LEVEL FLOW TOWARD THE NORTHWEST DURING THE COURSE OF THE
NIGHT WILL FOCUS THE MORE NUMEROUS SNOW SHOWERS SOUTH OF THE I-
96/969 CORRIDOR LATER THIS EVENING. THERE WILL BE AN OVERALL
WEAKENING TREND TO LAKE EFFECT DURING THE NIGHT UNDER CONTINUED LOW
LEVEL DRY AIR ADVECTION AND LOWERING CONVECTIVE DEPTHS AS A RESULT
OF INCREASING LARGE SCALE SUBSIDENCE. THIS WILL DIMINISH THE OVERALL
COVERAGE OF SNOW SHOWERS. A TRANSITION TOWARD MORE DOMINATE BANDING
IS POSSIBLE PRIOR TO DAYBREAK...WHICH MAY IMPACT FAR SOUTHERN
COUNTIES LATER TONIGHT. THIS IS A FAIRLY LOW CONFIDENCE
SCENARIO...SUGGESTING HOLDING JUST MINOR ADDITIONAL ACCUMULATIONS
TONIGHT ATTM. THE VEERING OF THE FLOW TOWARD THE NORTHWEST AND LOW
LEVEL DRY AIR ADVECTION WILL LEAD TO SOME CLEARING DURING THE COURSE
OF THE NIGHT /ESPECIALLY ACROSS THE SAGINAW VALLEY AND THUMB/. THIS
AND A GRADUAL WEAKENING GRADIENT WILL OFFER AN OPPORTUNITY FOR GOOD
RADIATIONAL COOLING /SUPPORTING MIN TEMPS IN THE SINGLE DIGITS TO
LOWER TEENS/.

&&

.LONG TERM...

THE SURGE OF STRONG PACIFIC ENERGY TAKING AIM ON THE PACIFIC
NORTHWEST OVER THE NEXT 24 HOURS HAS DEAMPLIFIED THE WEST COAST
RIDGE RESULTING IN A TRANSITION TO ZONAL FLOW ACROSS THE CONUS. THE
ZONAL REGIME WILL SPREAD INTO THE GREAT LAKES, FLOODING THE MID-
LEVELS WITH WARMER AIR, UPON THE DEPARTURE OF TODAY`S TROUGH.
BETWEEN 12Z FRIDAY AND 12Z SATURDAY, H85 TEMPERATURES OVER SOUTHEAST
MICHIGAN WILL RISE ABOUT 20 DEGREES AS THE MID-LEVEL CLIMB ABOVE
FREEZING BY SATURDAY MORNING. SHORTWAVE RIDGING EMBEDDED IN THE
DEVELOPING ZONAL FLOW WILL BUILD INTO THE AREA DURING THE DAY FRIDAY
AND EASE THE SURFACE HIGH OVER THE OHIO VALLEY EAST. RETURN FLOW AT
THE SURFACE WILL BE OF LITTLE HELP WITH ARCTIC AIR ENTRENCHED OVER
THE EASTERN US. TEMPERATURES WILL REMAIN IN THE UPPER TEENS/LOW 20S
TOMORROW THROUGH TOMORROW NIGHT. AS A RESULT, A STRONG INVERSION
WILL BEGIN TO TAKE SHAPE ON FRIDAY NIGHT AS THE SHORTWAVE OVER THE
INTERMOUNTAIN WEST EJECTS OUT OVER THE GREAT LAKES. ISENTROPIC
ASCENT AND A QUICK HIT OF PV ADVECTION 09Z-15Z SATURDAY MORNING WILL
SUPPORT AT LEAST A SCATTERED COVERAGE OF SHOWERS LIFTING THROUGH THE
AREA. CURRENT INDICATIONS ARE THAT THIS PRECIPITATION MAY FALL AS
FREEZING RAIN. SHORT DURATION AND LACK OF MAINTENANCE FOR SUB-ZERO
WET BULBING AT THE SURFACE LIMIT CONCERNS, BUT THE POTENTIAL FOR
SOME LIGHT ICING IS EVIDENT.

WEAK ISENTROPIC ASCENT WILL THEN BE ONGOING THROUGH THE DAY SATURDAY
AS A 100KT JET DEVELOPS OVERHEAD IN RESPONSE TO THE DEEPENING LONGWAVE
TROUGH UPSTREAM. THIS WILL HELP ORIENT A MID-LEVEL BAROCLINIC ZONE
ACROSS THE AREA WHICH WILL SERVE AS A FOCUS FOR ONGOING
PRECIPITATION DURING THE DAY. DRY MID-LEVELS SUGGEST THAT DRIZZLE,
AS OPPOSED TO SHOWERS, WILL BE WORTH KEEPING AN EYE ON. EITHER WAY,
TEMPERATURE RECOVERY DURING THIS TIME WILL BE IMPORTANT TO WATCH AS
AN ADDITIONAL FREEZING PRECIP THREAT COULD THEORETICALLY EVOLVE.
HOWEVER, THE SOLID SOUTHERLY GRADIENT COMBINED WITH THE NAM`S
TENDENCY TO HOLD ONTO LOW-LEVEL COLD AIR A BIT TOO LONG HELP
ALLEVIATE THAT CONCERN AT THIS TIME.

GLOBAL NWP REMAINS IN DECENT AGREEMENT WITH THE REST OF THE
FORECAST WITH SLIGHT DIFFERENCES IN TIMING AND LOCATION OF A
SURFACE LOW AS IT LIFTS NORTHWARD FROM THE SOUTHERN PLAINS TO
NORTHERN LOWER MICHIGAN SUNDAY MORNING TO MONDAY MORNING. WE REMAIN
ON THE WARM SIDE OF THE SYSTEM WITH A GOOD FEED OF MOISTURE SO A
RAINY PERIOD CAN BE EXPECTED...WITH THE HIGHEST POPS CENTERED ON
LATE SUNDAY TO EARLY MONDAY. SOME DISAGREEMENT EXISTS ON HOW FAST
THE UPPER WAVE AND ATTENDANT SURFACE LOW AND FORCING LIFT IN SUNDAY
SO THE DAY MAY NOT BE A COMPLETE WASHOUT...BUT WILL REFINE TIMING
WITH FUTURE FORECASTS. THE COLD FRONT MOVES THROUGH LATER MONDAY
USHERING A COLDER AIRMASS BACK IN SO THE WARMING TREND LOOKS TO BE
SHORT LIVED.
.

&&

.MARINE...

NORTHWEST WINDS GUSTING TO GALES WILL GRADUALLY EASE THROUGH TONIGHT
AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES. ALL GALE WARNINGS AND
SMALL CRAFT ADVISORIES ARE THEREFORE SCHEDULED TO EXPIRE
INCREMENTALLY THROUGH THE NIGHT AS WINDS AND WAVES SUBSIDE. A
MODERATE SOUTHWEST BREEZE WILL THEN DOMINATE THROUGH FRIDAY BEFORE
DEPARTURE OF HIGH PRESSURE TO THE EAST TRIGGERS AN INCREASE IN WINDS
AGAIN ON FRIDAY NIGHT. SOUTHWESTERLY GUSTS TO GALES OR NEAR GALES
WILL BE POSSIBLE FRIDAY NIGHT THROUGH THE FIRST HALF OF
SATURDAY...MAINLY OVER THE CENTRAL SW TO NE AXIS OF LAKE HURON.

&&

.AVIATION...ISSUED 1204 PM EST THU NOV 20 2014

//DISCUSSION...

LOW LEVEL CONVERGENCE HAS ENHANCED SNOW SHOWERS OFF LAKE MICHIGAN
AND BROUGHT THEM WELL INLAND INTO SE MI. INCREASED LOW LEVEL
INSTABILITY HAS FRACTURED SOME OF THE MORE PERSISTENT SNOW BANDS.
WHAT THIS MEANS IS THAT THERE WILL BE INTERVALS OF BREAKS AND BRIEF
INTENSE SNOW SHOWERS...IMPACTING MAINLY FNT AND PTK THROUGH THE
AFTERNOON. VISIBILITIES WITHIN SOME OF THE HEAVIER SNOW SHOWERS WILL
BE REDUCED TO LESS THAN A QUARTER MILE. THE LOW LEVEL WINDS WILL
VEER TOWARD THE W-NW THIS EVENING...PUSHING THE HIGHER CONCENTRATION
SNOW BANDS FARTHER SOUTH AND LEADING TO SOME CLEARING FROM NORTH TO
SOUTH.

FOR DTW...THROUGH THE AFTERNOON...THE MORE WIDESPREAD AND INTENSE
SNOW SHOWERS WILL REMAIN NORTH OF METRO. THE WINDS WILL TURN MORE
TOWARD THE WEST-NORTHWEST THIS EVENING /AFTER 00Z/ AND THIS MAY
BRING SOME OF THE HIGHER INTENSITY SNOW SHOWERS INTO METRO...
POSSIBLY LEADING TO SOME MINOR ACCUMULATIONS. CONTINUED VEERING OF
THE WINDS OVERNIGHT SHOULD PUSH LINGERING SNOW SHOWERS SOUTH OF
METRO AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5KFT.

* LOW CONFIDENCE IN BRIEF INTERVALS OF VISIBILITY BELOW A HALF MILE
  IN SNOW THIS EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ060>063-
     068>070.

LAKE HURON...GALE WARNING UNTIL 3 AM EST FRIDAY FOR LHZ362-363-441-462-463.

     SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LHZ421-442-
     443.

     GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LHZ361.

LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LEZ444.

     LOW WATER ADVISORY UNTIL 4 AM EST FRIDAY FOR LEZ444.

&&

$$

SHORT TERM...SC
LONG TERM....JVC/DT
MARINE.......JVC
AVIATION.....SC


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 202019
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
319 PM EST THU NOV 20 2014

.SHORT TERM...THIS EVENING AND TONIGHT

THE ONGOING SNOW SHOWERS ACROSS PORTIONS OF THE FORECAST AREA HAVE
BEEN THE RESULT OF LAKE EFFECT OFF LAKE MI...SUSTAINED THIS FAR EAST
BY STRONG WSW FLOW WITHIN AN ENHANCED W-E BOUNDARY LAYER CONVERGENCE
AXIS. CONVECTIVE UPDRAFTS HAVE BEEN WITHIN THE GOOD DENDRITIC GROWTH
LAYER...SO FLAKE SIZE HAS BEEN RESPECTABLE. A LONGER LIVED HEAVY BAND
OF SNOW IMPACTED LOCATIONS ALONG AN AXIS FROM SRN SHIAWASSEE/SRN
GENESEE/NRN OAKLAND COUNTIES INTO THE PORT HURON AREA EARLIER TODAY.
SPOTTER REPORTS SUGGEST A SOLID 3 TO 5 INCHES FELL IN THESE AREAS.
WHILE ACCUMULATIONS HAVE BEEN MUCH LESS OUTSIDE OF THIS REGION...THE
INTENSE SNOW SHOWERS HAVE STILL BEEN LEADING TO SPORADIC REDUCTIONS
IN VISIBILITIES AND A QUICK DUSTING OF ACCUMULATION. WINDS HAVE ALSO
INCREASED THIS AFTERNOON /WITH SOME GUSTS OVER 30 MPH REPORTED/
WHICH HAS BEEN CAUSING SOME BLOWING SNOW AND MINOR DRIFTING IN THE
ADVISORY AREA.

ONGOING MID LEVEL COLD AIR ADVECTION AND DAYTIME HEATING HAS BEEN
LIFTING CONVECTIVE DEPTHS THIS AFTERNOON. THIS HAS ACTUALLY RESULTED
IN SOME DISRUPTION TO THE MORE ORGANIZED BANDING. DEEPER MIXING HAS
ALSO LED TO A MORE UNIFORM WESTERLY SURFACE WIND ACROSS SRN
MI...WEAKENING THE CONVERGENCE IN THE BOUNDARY LAYER. THE PREVAILING
WESTERLY FLOW WILL STILL FOCUS THE MORE WIDESPREAD SNOW SHOWER
ACTIVITY ACROSS THE ADVISORY AREA THROUGH EVENING RUSH HOUR. VEERING
OF THE LOW LEVEL FLOW TOWARD THE NORTHWEST DURING THE COURSE OF THE
NIGHT WILL FOCUS THE MORE NUMEROUS SNOW SHOWERS SOUTH OF THE I-
96/969 CORRIDOR LATER THIS EVENING. THERE WILL BE AN OVERALL
WEAKENING TREND TO LAKE EFFECT DURING THE NIGHT UNDER CONTINUED LOW
LEVEL DRY AIR ADVECTION AND LOWERING CONVECTIVE DEPTHS AS A RESULT
OF INCREASING LARGE SCALE SUBSIDENCE. THIS WILL DIMINISH THE OVERALL
COVERAGE OF SNOW SHOWERS. A TRANSITION TOWARD MORE DOMINATE BANDING
IS POSSIBLE PRIOR TO DAYBREAK...WHICH MAY IMPACT FAR SOUTHERN
COUNTIES LATER TONIGHT. THIS IS A FAIRLY LOW CONFIDENCE
SCENARIO...SUGGESTING HOLDING JUST MINOR ADDITIONAL ACCUMULATIONS
TONIGHT ATTM. THE VEERING OF THE FLOW TOWARD THE NORTHWEST AND LOW
LEVEL DRY AIR ADVECTION WILL LEAD TO SOME CLEARING DURING THE COURSE
OF THE NIGHT /ESPECIALLY ACROSS THE SAGINAW VALLEY AND THUMB/. THIS
AND A GRADUAL WEAKENING GRADIENT WILL OFFER AN OPPORTUNITY FOR GOOD
RADIATIONAL COOLING /SUPPORTING MIN TEMPS IN THE SINGLE DIGITS TO
LOWER TEENS/.

&&

.LONG TERM...

THE SURGE OF STRONG PACIFIC ENERGY TAKING AIM ON THE PACIFIC
NORTHWEST OVER THE NEXT 24 HOURS HAS DEAMPLIFIED THE WEST COAST
RIDGE RESULTING IN A TRANSITION TO ZONAL FLOW ACROSS THE CONUS. THE
ZONAL REGIME WILL SPREAD INTO THE GREAT LAKES, FLOODING THE MID-
LEVELS WITH WARMER AIR, UPON THE DEPARTURE OF TODAY`S TROUGH.
BETWEEN 12Z FRIDAY AND 12Z SATURDAY, H85 TEMPERATURES OVER SOUTHEAST
MICHIGAN WILL RISE ABOUT 20 DEGREES AS THE MID-LEVEL CLIMB ABOVE
FREEZING BY SATURDAY MORNING. SHORTWAVE RIDGING EMBEDDED IN THE
DEVELOPING ZONAL FLOW WILL BUILD INTO THE AREA DURING THE DAY FRIDAY
AND EASE THE SURFACE HIGH OVER THE OHIO VALLEY EAST. RETURN FLOW AT
THE SURFACE WILL BE OF LITTLE HELP WITH ARCTIC AIR ENTRENCHED OVER
THE EASTERN US. TEMPERATURES WILL REMAIN IN THE UPPER TEENS/LOW 20S
TOMORROW THROUGH TOMORROW NIGHT. AS A RESULT, A STRONG INVERSION
WILL BEGIN TO TAKE SHAPE ON FRIDAY NIGHT AS THE SHORTWAVE OVER THE
INTERMOUNTAIN WEST EJECTS OUT OVER THE GREAT LAKES. ISENTROPIC
ASCENT AND A QUICK HIT OF PV ADVECTION 09Z-15Z SATURDAY MORNING WILL
SUPPORT AT LEAST A SCATTERED COVERAGE OF SHOWERS LIFTING THROUGH THE
AREA. CURRENT INDICATIONS ARE THAT THIS PRECIPITATION MAY FALL AS
FREEZING RAIN. SHORT DURATION AND LACK OF MAINTENANCE FOR SUB-ZERO
WET BULBING AT THE SURFACE LIMIT CONCERNS, BUT THE POTENTIAL FOR
SOME LIGHT ICING IS EVIDENT.

WEAK ISENTROPIC ASCENT WILL THEN BE ONGOING THROUGH THE DAY SATURDAY
AS A 100KT JET DEVELOPS OVERHEAD IN RESPONSE TO THE DEEPENING LONGWAVE
TROUGH UPSTREAM. THIS WILL HELP ORIENT A MID-LEVEL BAROCLINIC ZONE
ACROSS THE AREA WHICH WILL SERVE AS A FOCUS FOR ONGOING
PRECIPITATION DURING THE DAY. DRY MID-LEVELS SUGGEST THAT DRIZZLE,
AS OPPOSED TO SHOWERS, WILL BE WORTH KEEPING AN EYE ON. EITHER WAY,
TEMPERATURE RECOVERY DURING THIS TIME WILL BE IMPORTANT TO WATCH AS
AN ADDITIONAL FREEZING PRECIP THREAT COULD THEORETICALLY EVOLVE.
HOWEVER, THE SOLID SOUTHERLY GRADIENT COMBINED WITH THE NAM`S
TENDENCY TO HOLD ONTO LOW-LEVEL COLD AIR A BIT TOO LONG HELP
ALLEVIATE THAT CONCERN AT THIS TIME.

GLOBAL NWP REMAINS IN DECENT AGREEMENT WITH THE REST OF THE
FORECAST WITH SLIGHT DIFFERENCES IN TIMING AND LOCATION OF A
SURFACE LOW AS IT LIFTS NORTHWARD FROM THE SOUTHERN PLAINS TO
NORTHERN LOWER MICHIGAN SUNDAY MORNING TO MONDAY MORNING. WE REMAIN
ON THE WARM SIDE OF THE SYSTEM WITH A GOOD FEED OF MOISTURE SO A
RAINY PERIOD CAN BE EXPECTED...WITH THE HIGHEST POPS CENTERED ON
LATE SUNDAY TO EARLY MONDAY. SOME DISAGREEMENT EXISTS ON HOW FAST
THE UPPER WAVE AND ATTENDANT SURFACE LOW AND FORCING LIFT IN SUNDAY
SO THE DAY MAY NOT BE A COMPLETE WASHOUT...BUT WILL REFINE TIMING
WITH FUTURE FORECASTS. THE COLD FRONT MOVES THROUGH LATER MONDAY
USHERING A COLDER AIRMASS BACK IN SO THE WARMING TREND LOOKS TO BE
SHORT LIVED.
.

&&

.MARINE...

NORTHWEST WINDS GUSTING TO GALES WILL GRADUALLY EASE THROUGH TONIGHT
AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES. ALL GALE WARNINGS AND
SMALL CRAFT ADVISORIES ARE THEREFORE SCHEDULED TO EXPIRE
INCREMENTALLY THROUGH THE NIGHT AS WINDS AND WAVES SUBSIDE. A
MODERATE SOUTHWEST BREEZE WILL THEN DOMINATE THROUGH FRIDAY BEFORE
DEPARTURE OF HIGH PRESSURE TO THE EAST TRIGGERS AN INCREASE IN WINDS
AGAIN ON FRIDAY NIGHT. SOUTHWESTERLY GUSTS TO GALES OR NEAR GALES
WILL BE POSSIBLE FRIDAY NIGHT THROUGH THE FIRST HALF OF
SATURDAY...MAINLY OVER THE CENTRAL SW TO NE AXIS OF LAKE HURON.

&&

.AVIATION...ISSUED 1204 PM EST THU NOV 20 2014

//DISCUSSION...

LOW LEVEL CONVERGENCE HAS ENHANCED SNOW SHOWERS OFF LAKE MICHIGAN
AND BROUGHT THEM WELL INLAND INTO SE MI. INCREASED LOW LEVEL
INSTABILITY HAS FRACTURED SOME OF THE MORE PERSISTENT SNOW BANDS.
WHAT THIS MEANS IS THAT THERE WILL BE INTERVALS OF BREAKS AND BRIEF
INTENSE SNOW SHOWERS...IMPACTING MAINLY FNT AND PTK THROUGH THE
AFTERNOON. VISIBILITIES WITHIN SOME OF THE HEAVIER SNOW SHOWERS WILL
BE REDUCED TO LESS THAN A QUARTER MILE. THE LOW LEVEL WINDS WILL
VEER TOWARD THE W-NW THIS EVENING...PUSHING THE HIGHER CONCENTRATION
SNOW BANDS FARTHER SOUTH AND LEADING TO SOME CLEARING FROM NORTH TO
SOUTH.

FOR DTW...THROUGH THE AFTERNOON...THE MORE WIDESPREAD AND INTENSE
SNOW SHOWERS WILL REMAIN NORTH OF METRO. THE WINDS WILL TURN MORE
TOWARD THE WEST-NORTHWEST THIS EVENING /AFTER 00Z/ AND THIS MAY
BRING SOME OF THE HIGHER INTENSITY SNOW SHOWERS INTO METRO...
POSSIBLY LEADING TO SOME MINOR ACCUMULATIONS. CONTINUED VEERING OF
THE WINDS OVERNIGHT SHOULD PUSH LINGERING SNOW SHOWERS SOUTH OF
METRO AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5KFT.

* LOW CONFIDENCE IN BRIEF INTERVALS OF VISIBILITY BELOW A HALF MILE
  IN SNOW THIS EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ060>063-
     068>070.

LAKE HURON...GALE WARNING UNTIL 3 AM EST FRIDAY FOR LHZ362-363-441-462-463.

     SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LHZ421-442-
     443.

     GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LHZ361.

LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LEZ444.

     LOW WATER ADVISORY UNTIL 4 AM EST FRIDAY FOR LEZ444.

&&

$$

SHORT TERM...SC
LONG TERM....JVC/DT
MARINE.......JVC
AVIATION.....SC


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





000
FXUS63 KDTX 201704
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1204 PM EST THU NOV 20 2014


.AVIATION...

//DISCUSSION...

LOW LEVEL CONVERGENCE HAS ENHANCED SNOW SHOWERS OFF LAKE MICHIGAN
AND BROUGHT THEM WELL INLAND INTO SE MI. INCREASED LOW LEVEL
INSTABILITY HAS FRACTURED SOME OF THE MORE PERSISTENT SNOW BANDS.
WHAT THIS MEANS IS THAT THERE WILL BE INTERVALS OF BREAKS AND BRIEF
INTENSE SNOW SHOWERS...IMPACTING MAINLY FNT AND PTK THROUGH THE
AFTERNOON. VISIBILITIES WITHIN SOME OF THE HEAVIER SNOW SHOWERS WILL
BE REDUCED TO LESS THAN A QUARTER MILE. THE LOW LEVEL WINDS WILL
VEER TOWARD THE W-NW THIS EVENING...PUSHING THE HIGHER CONCENTRATION
SNOW BANDS FARTHER SOUTH AND LEADING TO SOME CLEARING FROM NORTH TO
SOUTH.

FOR DTW...THROUGH THE AFTERNOON...THE MORE WIDESPREAD AND INTENSE
SNOW SHOWERS WILL REMAIN NORTH OF METRO. THE WINDS WILL TURN MORE
TOWARD THE WEST-NORTHWEST THIS EVENING /AFTER 00Z/ AND THIS MAY
BRING SOME OF THE HIGHER INTENSITY SNOW SHOWERS INTO METRO...
POSSIBLY LEADING TO SOME MINOR ACCUMULATIONS. CONTINUED VEERING OF
THE WINDS OVERNIGHT SHOULD PUSH LINGERING SNOW SHOWERS SOUTH OF
METRO AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5KFT.

* LOW CONFIDENCE IN BRIEF INTERVALS OF VISIBILITY BELOW A HALF MILE
  IN SNOW THIS EVENING.

&&

.PREV DISCUSSION...ISSUED 932 AM EST THU NOV 20 2014

UPDATE...

AN ENHANCED REGION OF CONVERGENCE HAS LED TO A BAND OF HEAVY SNOW
JUST SOUTH OF THE I-69 CORRIDOR ACROSS SHIAWASSEE...GENESEE AND
LAPEER COUNTIES. THIS RIBBON OF CONVERGENCE WILL PERSIST AT LEAST
INTO EARLY AFTERNOON. BASED OFF THE 12Z DTX SOUNDING...DECENT LOW
LEVEL INSTABILITY AND MOISTURE IS LEADING TO THE HEALTHY RESPONSE
TO THE LAKE EFFECT ACTIVITY OFF LAKE MI. THERE MAY BE SOME BREAK
UP OR REORIENTATION OF THE BANDING THIS AFTERNOON...POSSIBLY
LEADING TO ENHANCED CONVERGENCE FARTHER SOUTH. OBSERVATIONAL DATA
AT THIS POINT SUGGESTS THE BAND NEAR THE I-69 CORRIDOR WILL BE
PERSISTENT ENOUGH TO SUPPORT SOME LOCALIZED ACCUMULATIONS IN
EXCESS OF THREE INCHES. THERE HAS ALSO BEEN A SPOTTER REPORT OF
WHITE OUT CONDITIONS IN THIS BAND. THIS HAS PROMPTED THE ISSUANCE
OF A WINTER WEATHER ADVISORY FOR SHIAWASSEE...GENESEE AND LAPEER
COUNITES THROUGH 4 PM.

PREV DISCUSSION...ISSUED 349 AM EST THU NOV 20 2014

SHORT TERM...TODAY AND TONIGHT

LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO FUNNEL WEST TO EAST ACROSS
LOWER MICHIGAN AND IMPACT PARTS OF THE CWA...ESPECIALLY BETWEEN I 69
AND I 94 TODAY. AFTER AN INITIAL BURST OF LOCALLY INTENSE SNOW
SQUALLS ENHANCED BY SHORTWAVE TROUGH USHERING IN NEXT SHOT OF ARCTIC
AIR...THE REMAINING SNOW SHOWERS SHOULD REMAIN ON THE LIGHT TO
MODERATE SIDE AND REMAIN QUITE A BIT LESS ORGANIZED. SO...GENERALLY
DO NOT EXPECT MORE THAN AN ADDITIONAL INCH OR SO OF ACCUMULATIONS
EARLY THIS MORNING THROUGH TODAY. THAT SAID...DIURNAL ENHANCEMENT OF
THE SNOW SHOWER ACTIVITY MAY LEAD TO ISOLATED AMOUNTS UP TO 2 INCHES
IN THE I 69 TO M 58 CORRIDORS WHERE CONVERGENCE WILL BE STRONGEST.

A GRADUAL VEERING OF LOW LEVEL FLOW FROM WEST TO WEST/NORTHWEST WILL
RE-FOCUS SNOW SHOWERS OVER THE SOUTHERN CWA BY THE EVENING...WITH
SUBSTANTIAL WEAKENING OF ACTIVITY EXPECTED AFTER MIDNIGHT TONIGHT A
RIDGE OF HIGH PRESSURE BEGINS TO BUILD INTO THE AREA. A DUSTING TO
INCH OF SNOW CANNOT BE RULED OUT DURING THE EVENING I 94 SOUTH
BEFORE THIS WEAKENING TREND ENSUES.

WITH THE RE-ENFORCING SHOT OF ARCTIC AIR...TEMPERATURES WILL NOT GO
ANYWHERE TODAY...HOLDING GENERALLY IN THE LOWER/MID 20S...AND THEN
FALLING WELL INTO THE TEENS TONIGHT. IN FACT...SINGLE DIGITS WILL BE
COMMON OVER THE NORTHERN CWA WHERE SKIES WILL BECOME CLEAR/PARTLY
CLOUDY AND ALLOW FOR DECENT RADIATIONAL COOLING...HELPED ALONG BY
DECREASING WINDS WITH THE APPROACHING RIDGE.

LONG TERM...FRIDAY THROUGH NEXT WEDNESDAY

SOME MOVEMENT IN THE LONGWAVE PATTERN WILL HELP PUSH THE PERSISTENT
AND COLD TROUGH OUT TO THE ATLANTIC. A SPLIT FLOW PATTERN THEN TRIES
TO TAKE SHAPE AS RESIDIUAL NORTHERN STREAM ENERGY LINGERS OVER
EASTERN CANADA AND SOUTHERN STREAM INTENSIFIES ACROSS THE SOUTHERN
CONUS WITH THE NEXT SERIES OF WAVES. THIS WILL LEAD TO A WARM UP
OVER THE GREAT LAKES OVER THE WEEKEND BUT COOLER WEATHER RETURNS
NEXT WEEK.

FRIDAY WILL BE A TRANSITIONAL DAY AS THE TROUGH EXITS THE GREAT
LAKES BUT THE THERMAL TROUGH LINGERS ONE MORE DAY. AS HEIGHTS BUILD
AND HIGH PRESSURE SLIDES THROUGH THE AREA...850MB TEMPS WILL RISE
FROM AROUND -18C AT 12Z FRI UP TO -4C BY 00Z SAT. LESS OF A CHANGE
WILL BE REALIZED AT THE SFC AS COLD AIR REMAINS LOCKED IN PLACE
UNDER THE INVERSION. THIS WILL KEEP MAX TEMPS IN THE MID 20S. WAA
KICK IN FRI NIGHT WITH THE AIDE OF A 50 KNOT LL JET. THIS STRONG SW
FLOW WILL HELP RAISE 925MB AND 850MB TEMPS ABOVE ZERO BY 12Z SAT.
MODELS CONTINUE TO SHOW A LAG IN SFC TEMPS WARMING...KEEPING SUB
FREEZING TEMPS IN THE LOWEST 1000+FT OF THE COLUMN. THOUGH THE
SOUTHERN STREAM TROUGH AND ASSOCIATED SFC LOW AREA STILL COMING
TOGETHER AT THIS TIME...MODELS HAVE CONSISTENTLY BEEN SHOWING A
SHORTWAVE LIFTING THROUGH SOUTHERN MI AHEAD OF THE MAIN SYSTEM. WITH
THE AFOREMENTION THERMAL PROFILE...LIGHT FREEZING DRIZZLE/RAIN WILL
BE POSSIBLE ACROSS THE AREA EARLY IN THE DAY. AS THE DAY PROGRESSES
AND WAA CONTINUES...THE PTYPE WILL EVENTUALLY CHANGE OVER TO A PURE
RAIN SCENARIO. SO WILL CONTINUE TO HIGHLIGHT THESE PTYPE CONCERNS IN
THE GRIDS.

TEMPERATURES WILL CLIMB SAT THROUGH MON AS THE TROUGH DEEPENS OVER
THE CENTRAL PLAINS CAUSING THE DOWNSTREAM AMPLIFICATION OF THE RIDGE
OVER THE EAST COAST. TEMPERATURES LOOK TO RETURN TO NEAR NORMAL FOR
MID NOVEMBER REACHING INTO THE UPPER 40S TO NEAR 50 AS 850MB TEMPS
CLIMB TO +6C SUN AND +7C EARLY MON. THIS WILL CHANGE ALL PRECIP OVER
TO RAIN FOR THE NEXT FEW DAYS AS AN UPPER LEVEL SHORTWAVE OVER TEXAS
LIFTS NE AND PHASES WITH A NORTHERN STREAM WAVE SUNDAY NIGHT INTO
MONDAY. THE LEAD EXTENSION OF THE WARM FRONT WILL DRAPE ACROSS THE
REGION THROUGH THE WEEKEND AS THE SFC LOW LIFTS INTO THE MIDWEST
WHILE STRENGTHENING. THE LEAD FRONTAL SFC WILL RESULT IN PERIODS OF
SHOWERS AS RIPPLES EJECTING OUT OF THE TROUGH LIFT OVER THE REGION
INCREASING ISENTROPIC ASCENT AND WEAK FGEN. THE BULK OF THE RAIN
SHOWERS WILL OCCUR SUNDAY EVENING THROUGH MONDAY MORNING AS THE LOW
PASSES OVER THE NORTHERN GREAT LAKES. A COLD FRONT WILL THEN SLIDE
THROUGH ON MONDAY USHERING MORE ARCTIC AIR INTO THE STATE. THE COLD
AIR WILL CHANGE THE RAIN OVER TO SNOW LATE MONDAY NIGHT. THEN ON
TUESDAY THE BACKSIDE TROUGH/DEFORMATION AXIS WILL SLIDE THROUGH THE
AREA KEEPING SNOW CHANCES AROUND. HIGH TEMPERATURES WILL FALL BACK
TO THE LOW 30S MIDWEEK WITH THIS LATEST BATCH OF ARCTIC AIR.

MARINE...

A DEEPENING LOW PRESSURE SYSTEM OVER THE NORTHEASTERN GREAT LAKES IS
PRODUCING A VERY TIGHT PRESSURE GRADIENT OVER THE REGION. THE
INFILTRATION OF YET ANOTHER SURGE OF ARCTIC AIR HAS DECREASED THE
STABILITY...AND IN COMBINATION WITH THE GRADIENT FLOW HAS LEAD TO
ANOTHER ROUND OF GALES OVER LAKE HURON. OBSERVATIONS HAVE BEEN
STEADILY IN THE 35 TO 40 KNOT RANGE OVER MOST OF THE BASIN EXCLUDING
ONLY A FEW NEARSHORE ZONES. THESE WESTERLY GALES WILL CONTINUE INTO
TONIGHT BEFORE HIGH PRESSURE BUILDING INTO THE AREA HELPS RELAX THE
GRADIENT AND WINDS SOME ON FRIDAY. COLD UNSTABLE AIR WILL CONTINUE
TO RESIDE OVER THE EASTERN LAKES INTO THE WEEKEND BUT A LOWER MIXED
LAYER WILL RESULT IN WINDS LESS THAN GALE FORCE DURING THAT TIME.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ060>063-
     068>070.

LAKE HURON...GALE WARNING UNTIL 3 AM EST FRIDAY FOR LHZ362-363-421-441-462>464.

     SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LHZ442-443.

     GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LHZ361.

     GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LHZ422.

LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LEZ444.

     LOW WATER ADVISORY UNTIL 4 AM EST FRIDAY FOR LEZ444.

&&

$$

AVIATION.....SC
UPDATE.......SC
SHORT TERM...DG
LONG TERM....DRK
MARINE.......DRK


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).




000
FXUS63 KDTX 201704
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1204 PM EST THU NOV 20 2014


.AVIATION...

//DISCUSSION...

LOW LEVEL CONVERGENCE HAS ENHANCED SNOW SHOWERS OFF LAKE MICHIGAN
AND BROUGHT THEM WELL INLAND INTO SE MI. INCREASED LOW LEVEL
INSTABILITY HAS FRACTURED SOME OF THE MORE PERSISTENT SNOW BANDS.
WHAT THIS MEANS IS THAT THERE WILL BE INTERVALS OF BREAKS AND BRIEF
INTENSE SNOW SHOWERS...IMPACTING MAINLY FNT AND PTK THROUGH THE
AFTERNOON. VISIBILITIES WITHIN SOME OF THE HEAVIER SNOW SHOWERS WILL
BE REDUCED TO LESS THAN A QUARTER MILE. THE LOW LEVEL WINDS WILL
VEER TOWARD THE W-NW THIS EVENING...PUSHING THE HIGHER CONCENTRATION
SNOW BANDS FARTHER SOUTH AND LEADING TO SOME CLEARING FROM NORTH TO
SOUTH.

FOR DTW...THROUGH THE AFTERNOON...THE MORE WIDESPREAD AND INTENSE
SNOW SHOWERS WILL REMAIN NORTH OF METRO. THE WINDS WILL TURN MORE
TOWARD THE WEST-NORTHWEST THIS EVENING /AFTER 00Z/ AND THIS MAY
BRING SOME OF THE HIGHER INTENSITY SNOW SHOWERS INTO METRO...
POSSIBLY LEADING TO SOME MINOR ACCUMULATIONS. CONTINUED VEERING OF
THE WINDS OVERNIGHT SHOULD PUSH LINGERING SNOW SHOWERS SOUTH OF
METRO AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5KFT.

* LOW CONFIDENCE IN BRIEF INTERVALS OF VISIBILITY BELOW A HALF MILE
  IN SNOW THIS EVENING.

&&

.PREV DISCUSSION...ISSUED 932 AM EST THU NOV 20 2014

UPDATE...

AN ENHANCED REGION OF CONVERGENCE HAS LED TO A BAND OF HEAVY SNOW
JUST SOUTH OF THE I-69 CORRIDOR ACROSS SHIAWASSEE...GENESEE AND
LAPEER COUNTIES. THIS RIBBON OF CONVERGENCE WILL PERSIST AT LEAST
INTO EARLY AFTERNOON. BASED OFF THE 12Z DTX SOUNDING...DECENT LOW
LEVEL INSTABILITY AND MOISTURE IS LEADING TO THE HEALTHY RESPONSE
TO THE LAKE EFFECT ACTIVITY OFF LAKE MI. THERE MAY BE SOME BREAK
UP OR REORIENTATION OF THE BANDING THIS AFTERNOON...POSSIBLY
LEADING TO ENHANCED CONVERGENCE FARTHER SOUTH. OBSERVATIONAL DATA
AT THIS POINT SUGGESTS THE BAND NEAR THE I-69 CORRIDOR WILL BE
PERSISTENT ENOUGH TO SUPPORT SOME LOCALIZED ACCUMULATIONS IN
EXCESS OF THREE INCHES. THERE HAS ALSO BEEN A SPOTTER REPORT OF
WHITE OUT CONDITIONS IN THIS BAND. THIS HAS PROMPTED THE ISSUANCE
OF A WINTER WEATHER ADVISORY FOR SHIAWASSEE...GENESEE AND LAPEER
COUNITES THROUGH 4 PM.

PREV DISCUSSION...ISSUED 349 AM EST THU NOV 20 2014

SHORT TERM...TODAY AND TONIGHT

LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO FUNNEL WEST TO EAST ACROSS
LOWER MICHIGAN AND IMPACT PARTS OF THE CWA...ESPECIALLY BETWEEN I 69
AND I 94 TODAY. AFTER AN INITIAL BURST OF LOCALLY INTENSE SNOW
SQUALLS ENHANCED BY SHORTWAVE TROUGH USHERING IN NEXT SHOT OF ARCTIC
AIR...THE REMAINING SNOW SHOWERS SHOULD REMAIN ON THE LIGHT TO
MODERATE SIDE AND REMAIN QUITE A BIT LESS ORGANIZED. SO...GENERALLY
DO NOT EXPECT MORE THAN AN ADDITIONAL INCH OR SO OF ACCUMULATIONS
EARLY THIS MORNING THROUGH TODAY. THAT SAID...DIURNAL ENHANCEMENT OF
THE SNOW SHOWER ACTIVITY MAY LEAD TO ISOLATED AMOUNTS UP TO 2 INCHES
IN THE I 69 TO M 58 CORRIDORS WHERE CONVERGENCE WILL BE STRONGEST.

A GRADUAL VEERING OF LOW LEVEL FLOW FROM WEST TO WEST/NORTHWEST WILL
RE-FOCUS SNOW SHOWERS OVER THE SOUTHERN CWA BY THE EVENING...WITH
SUBSTANTIAL WEAKENING OF ACTIVITY EXPECTED AFTER MIDNIGHT TONIGHT A
RIDGE OF HIGH PRESSURE BEGINS TO BUILD INTO THE AREA. A DUSTING TO
INCH OF SNOW CANNOT BE RULED OUT DURING THE EVENING I 94 SOUTH
BEFORE THIS WEAKENING TREND ENSUES.

WITH THE RE-ENFORCING SHOT OF ARCTIC AIR...TEMPERATURES WILL NOT GO
ANYWHERE TODAY...HOLDING GENERALLY IN THE LOWER/MID 20S...AND THEN
FALLING WELL INTO THE TEENS TONIGHT. IN FACT...SINGLE DIGITS WILL BE
COMMON OVER THE NORTHERN CWA WHERE SKIES WILL BECOME CLEAR/PARTLY
CLOUDY AND ALLOW FOR DECENT RADIATIONAL COOLING...HELPED ALONG BY
DECREASING WINDS WITH THE APPROACHING RIDGE.

LONG TERM...FRIDAY THROUGH NEXT WEDNESDAY

SOME MOVEMENT IN THE LONGWAVE PATTERN WILL HELP PUSH THE PERSISTENT
AND COLD TROUGH OUT TO THE ATLANTIC. A SPLIT FLOW PATTERN THEN TRIES
TO TAKE SHAPE AS RESIDIUAL NORTHERN STREAM ENERGY LINGERS OVER
EASTERN CANADA AND SOUTHERN STREAM INTENSIFIES ACROSS THE SOUTHERN
CONUS WITH THE NEXT SERIES OF WAVES. THIS WILL LEAD TO A WARM UP
OVER THE GREAT LAKES OVER THE WEEKEND BUT COOLER WEATHER RETURNS
NEXT WEEK.

FRIDAY WILL BE A TRANSITIONAL DAY AS THE TROUGH EXITS THE GREAT
LAKES BUT THE THERMAL TROUGH LINGERS ONE MORE DAY. AS HEIGHTS BUILD
AND HIGH PRESSURE SLIDES THROUGH THE AREA...850MB TEMPS WILL RISE
FROM AROUND -18C AT 12Z FRI UP TO -4C BY 00Z SAT. LESS OF A CHANGE
WILL BE REALIZED AT THE SFC AS COLD AIR REMAINS LOCKED IN PLACE
UNDER THE INVERSION. THIS WILL KEEP MAX TEMPS IN THE MID 20S. WAA
KICK IN FRI NIGHT WITH THE AIDE OF A 50 KNOT LL JET. THIS STRONG SW
FLOW WILL HELP RAISE 925MB AND 850MB TEMPS ABOVE ZERO BY 12Z SAT.
MODELS CONTINUE TO SHOW A LAG IN SFC TEMPS WARMING...KEEPING SUB
FREEZING TEMPS IN THE LOWEST 1000+FT OF THE COLUMN. THOUGH THE
SOUTHERN STREAM TROUGH AND ASSOCIATED SFC LOW AREA STILL COMING
TOGETHER AT THIS TIME...MODELS HAVE CONSISTENTLY BEEN SHOWING A
SHORTWAVE LIFTING THROUGH SOUTHERN MI AHEAD OF THE MAIN SYSTEM. WITH
THE AFOREMENTION THERMAL PROFILE...LIGHT FREEZING DRIZZLE/RAIN WILL
BE POSSIBLE ACROSS THE AREA EARLY IN THE DAY. AS THE DAY PROGRESSES
AND WAA CONTINUES...THE PTYPE WILL EVENTUALLY CHANGE OVER TO A PURE
RAIN SCENARIO. SO WILL CONTINUE TO HIGHLIGHT THESE PTYPE CONCERNS IN
THE GRIDS.

TEMPERATURES WILL CLIMB SAT THROUGH MON AS THE TROUGH DEEPENS OVER
THE CENTRAL PLAINS CAUSING THE DOWNSTREAM AMPLIFICATION OF THE RIDGE
OVER THE EAST COAST. TEMPERATURES LOOK TO RETURN TO NEAR NORMAL FOR
MID NOVEMBER REACHING INTO THE UPPER 40S TO NEAR 50 AS 850MB TEMPS
CLIMB TO +6C SUN AND +7C EARLY MON. THIS WILL CHANGE ALL PRECIP OVER
TO RAIN FOR THE NEXT FEW DAYS AS AN UPPER LEVEL SHORTWAVE OVER TEXAS
LIFTS NE AND PHASES WITH A NORTHERN STREAM WAVE SUNDAY NIGHT INTO
MONDAY. THE LEAD EXTENSION OF THE WARM FRONT WILL DRAPE ACROSS THE
REGION THROUGH THE WEEKEND AS THE SFC LOW LIFTS INTO THE MIDWEST
WHILE STRENGTHENING. THE LEAD FRONTAL SFC WILL RESULT IN PERIODS OF
SHOWERS AS RIPPLES EJECTING OUT OF THE TROUGH LIFT OVER THE REGION
INCREASING ISENTROPIC ASCENT AND WEAK FGEN. THE BULK OF THE RAIN
SHOWERS WILL OCCUR SUNDAY EVENING THROUGH MONDAY MORNING AS THE LOW
PASSES OVER THE NORTHERN GREAT LAKES. A COLD FRONT WILL THEN SLIDE
THROUGH ON MONDAY USHERING MORE ARCTIC AIR INTO THE STATE. THE COLD
AIR WILL CHANGE THE RAIN OVER TO SNOW LATE MONDAY NIGHT. THEN ON
TUESDAY THE BACKSIDE TROUGH/DEFORMATION AXIS WILL SLIDE THROUGH THE
AREA KEEPING SNOW CHANCES AROUND. HIGH TEMPERATURES WILL FALL BACK
TO THE LOW 30S MIDWEEK WITH THIS LATEST BATCH OF ARCTIC AIR.

MARINE...

A DEEPENING LOW PRESSURE SYSTEM OVER THE NORTHEASTERN GREAT LAKES IS
PRODUCING A VERY TIGHT PRESSURE GRADIENT OVER THE REGION. THE
INFILTRATION OF YET ANOTHER SURGE OF ARCTIC AIR HAS DECREASED THE
STABILITY...AND IN COMBINATION WITH THE GRADIENT FLOW HAS LEAD TO
ANOTHER ROUND OF GALES OVER LAKE HURON. OBSERVATIONS HAVE BEEN
STEADILY IN THE 35 TO 40 KNOT RANGE OVER MOST OF THE BASIN EXCLUDING
ONLY A FEW NEARSHORE ZONES. THESE WESTERLY GALES WILL CONTINUE INTO
TONIGHT BEFORE HIGH PRESSURE BUILDING INTO THE AREA HELPS RELAX THE
GRADIENT AND WINDS SOME ON FRIDAY. COLD UNSTABLE AIR WILL CONTINUE
TO RESIDE OVER THE EASTERN LAKES INTO THE WEEKEND BUT A LOWER MIXED
LAYER WILL RESULT IN WINDS LESS THAN GALE FORCE DURING THAT TIME.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ060>063-
     068>070.

LAKE HURON...GALE WARNING UNTIL 3 AM EST FRIDAY FOR LHZ362-363-421-441-462>464.

     SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LHZ442-443.

     GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LHZ361.

     GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LHZ422.

LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR LEZ444.

     LOW WATER ADVISORY UNTIL 4 AM EST FRIDAY FOR LEZ444.

&&

$$

AVIATION.....SC
UPDATE.......SC
SHORT TERM...DG
LONG TERM....DRK
MARINE.......DRK


YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).





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