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000
FXUS63 KDTX 020359
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1159 PM EDT WED OCT 1 2014


.AVIATION...

//DISCUSSION...

LIGHT SOUTHEAST FLOW CONTINUES TO FUNNEL LOW LEVEL MOISTURE INTO THE
AREA AND FOG/STRATUS IS ALREADY RE-FORMING LATE THIS EVENING WITH A
LARGER AREA OF IFR/LIFR CIGS ALSO SPREADING BACK WEST TOWARDS REGION
FROM ONTARIO/LAKE ERIE. WILL MAINTAIN IFR CIGS OVERNIGHT WITH VSBYS
ALSO FALLING INTO THE 1-2SM RANGE INTO EARLY THURSDAY MORNING. WITH
ANY LUCK...CIRRUS STREAMING INTO THE AREA WILL KEEP WIDESPREAD DENSE
FOG AT BAY OVERNIGHT. CONDITIONS WILL IMPROVE WITHIN INCREASED SOUTH
TO SOUTHEAST FLOW ON THURSDAY IN ADVANCE OF APPROACHING TROUGH. CIGS
WILL LIFT TO VFR...MAINLY FROM LEAD MOISTURE SHIFTING IN FROM THE
WEST WITH THIS NEXT SYSTEM.

//DTW THRESHOLD THREATS...

* MEDIUM TO HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET OVERNIGHT
INTO EARLY THURSDAY MORNING...WITH LOWER CONFIDENCE ON THURSDAY.

* LOW CONFIDENCE IN CEILINGS AOB 200 FT AND/OR VSBYS AOB 1/2SM FROM
ABOUT 06Z-14Z.

&&

.PREV DISCUSSION...ISSUED 354 PM EDT WED OCT 1 2014

SHORT TERM...TONIGHT

SOUTHEASTERN MICHIGAN WILL REMAIN UNDER THE SPELL OF THE STRONG
SURFACE ANTICYCLONE TONIGHT OVER PORTIONS OF EASTERN QUEBEC AND
CANADIAN MARITIMES WITH A SUBSTANTIAL SURFACE RIDGE EXTENDING BACK
INTO THE GREAT LAKES REGION. THIS FEATURE WILL CONTINUE TO DIRECT A
SOUTHEASTERLY LOW TROPOSPHERE FEED INTO THE STATE DESPITE A WEAK
MIDLEVEL RIDGE SLIDING OVERHEAD. THIS UPPER LEVEL RIDGE WILL
ESSENTIALLY CAUSE THE PATTERN LOCALLY TO REMAIN STAGNANT THROUGH THE
OVERNIGHT...DISALLOWING MUCH IN THE WAY OF ADVECTIONS OR AIRMASS
TURNOVER. CLOUD TRENDS THIS AFTERNOON HAVE BEEN SLUGGISH IN MANY
AREAS WITH A TRANSITION FROM STRATUS TO CUMULOFORM. THERE HAS BEEN A
RAPID CLEARING TREND OVER PORTIONS OF SOUTH CENTRAL LOWER MICHIGAN
BUT SUSPECT THIS TO SLOW DOWN AND NOT MAKE MUCH INROADS TO
SOUTHEASTERN MICHIGAN BEFORE SUNDOWN. INSTEAD...EXPECT VERTICAL
CLOUD CIRCULATIONS TO DEEPEN YET OVER THE NEXT 4 HOURS WHICH WILL
SUPPORT GREATER CONVECTIVE ELEMENT SPACING AND INTRODUCE GREATER
CLOUD SCALE SUBSIDENCE AND ENTRAINMENT OF DRY AIR ALOFT. THIS SHOULD
SET THE STAGES FOR A RAPID CLEARING TREND IN MANY AREAS POST SUNSET
WITH NOCTURNAL COOLING.

NAM AND LATEST HRRR NWP IS VERY SUPPORTIVE OF FOG TONIGHT WITH A
MUCH BETTER PROFILE FOR NEAR SURFACE SATURATION IN COMPARISON TO
YESTERDAY MORNING. GIVEN THE AFOREMENTIONED LACK OF ADVECTIONS ALONG
WITH THE CONTINUATION OF GREENUP ACROSS THE AREA...HIGH AMBIENT
MOISTURE IN THE BACKGROUND SHOULD SUPPORT FOG FAIRLY EARLY
TONIGHT...I.E. SHORTLY AFTER MIDNIGHT. EXPECTATIONS ARE FOR FOG TO
DEVELOP ACROSS PORTIONS OF ONTARIO...PORT HURON AND THE EASTERN
THUMB BEFORE SPREADING WESTWARD. MODELS ARE ALSO SHOWING A SIGNAL
THAT AREAS SOUTH AND EAST OF THE TERRAIN IN HIGHER SURFACE PRESSURE
AREAS COULD VERY WELL BE A FAVORABLE ZONE FOR FOG DEVELOPMENT. GIVEN
THERMODYNAMIC STRUCTURE...DENSE FOG WILL BE POSSIBLE. CONFIDENCE IS
NOT 100 PERCENT AS IT SELDOM IS...AND WILL GIVE LATER SHIFTS THE
FLEXIBILITY ON ANY POSSIBLE HEADLINE DECISIONS.

LONG TERM...

THE NORTHERN PORTION OF THE EXISTING LONGWAVE TROUGHING NOW
ENCOMPASSING MUCH OF THE WESTERN CONUS WILL UNDERGO SUBSTANTIAL
AMPLIFICATION OVER THE NEXT 48 HOURS.  THIS PROCESS WILL COMMENCE AS
STRONG SHORTWAVE ENERGY AND AN ATTENDANT 140 KT UPPER JET CORE
CURRENTLY OVER BRITISH COLUMBIA DIG INTO THE LOWER HEIGHT FIELD.
STRENGTHENING DYNAMICS ATTENDANT TO A LEAD WAVE UNDERCUTTING THE
AMPLIFYING TROUGH WILL BRING A PERIOD OF ACTIVE WEATHER TO END THE
WORK WEEK.  THE DEEPENING PROCESS WILL THEN LEAVE A CLOSED LOW
CONFIGURATION CENTERED JUST TO THE NORTH FOR THE UPCOMING
WEEKEND...SPELLING A CONSIDERABLY COLDER AND UNSETTLED PERIOD.

A DEEPER SOUTHWESTERLY FLOW TAKES HOLD ON THURSDAY AS THE
GRADUALLY EXPANDING HEIGHT FALLS NUDGE THE EXISTING UPPER RIDGE TO
THE EAST.  THIS PROCESS WILL MIX OUT ANY LINGERING FOG THROUGH LATE
MORNING...WITH THE ENSUING INCREASE IN MID LEVEL WARM AIR AND
THETA-E ADVECTION PROMPTING A STEADY THICKENING OF A HIGH BASED
CLOUD DECK DURING THE FIRST HALF OF THE DAY.  DESPITE THE WARMING
THERMAL PROFILE...A LINGERING SOUTHEAST SURFACE WIND AND LIMITED
MIXING DEPTH WILL MUTE THE OVERALL RESPONSE SLIGHTLY.  IN ACCORDANCE
WITH THE GOING FORECAST...WILL CONTINUE TO TEMPER EXPECTATIONS WITH
HIGHS OF LOW TO MID 70S.  TANGIBLE FORCING THROUGH THE DAYLIGHT
PERIOD REMAINS LESS DEFINED LOCALLY...THE AREA LARGELY REMOVED TO
THE EAST FROM THE MAIN CORRIDOR OF ASCENT LOCKED ONTO THE
THETA-E RIDGE AND PRIMARY TRAJECTORY OF ANY LOWER AMPLITUDE SHORTWAVE
ENERGY FUNNELING THROUGH THE MEAN SW FLOW.  THERE REMAINS THE
POTENTIAL FOR THIS AXIS TO CREEP FAR ENOUGH EAST TO SUPPORT SOME
LIGHT SHOWER DEVELOPMENT...PARTICULARLY ACROSS THE TRI-CITIES.  LOW
CHANCE POPS REMAIN APPROPRIATE FOR THIS AREA GIVEN THE HIGH DEGREE
OF UNCERTAINTY.

THE INCREASING INTERACTION BETWEEN THE AFOREMENTIONED SOUTHERN
WAVE EJECTING NORTHEAST OUT OF THE SOUTHERN PLAINS AND THE DEEPENING
LOW ACROSS THE DAKOTAS WILL PROMPT RAPID SURFACE CYCLOGENESIS AND A
STRENGTHENING OF THE ATTENDANT COLD FRONT UPSTREAM BY THURSDAY
NIGHT.  THE DOWNSTREAM PROPAGATION OF A STRENGTHENING WIND FIELD
/50 KTS AT 850MB/ EMBEDDED WITHIN THE WARM SECTOR AND AT THE EDGE OF
THE INBOUND LOWER HEIGHT FIELD WILL LIKELY PROMOTE AN EXPANSION IN
PRECIPITATION COVERAGE THROUGHOUT THE MIDWEST BY LATE THURSDAY.
THIS FORCING REMAINS FORECAST TO TRACK THROUGH SE MICHIGAN LATE
THURSDAY NIGHT AND EARLY FRIDAY...A CORRESPONDING STEADY INCREASE IN
PRECIPITATION CHANCES COMMENCING DURING THIS TIME.  DEEPEST ASCENT
IN PLACE DURING THE FIRST HALF OF FRIDAY...A PERIOD OF SOLID UPPER
DIVERGENCE AND CVA WORKING INTO A MOISTENING PRE-FRONTAL
ENVIRONMENT.  EXISTING MID LEVEL INSTABILITY CERTAINLY SUFFICIENT TO
SUPPORT A THUNDER MENTION...A FEW STRONGER GUSTS A POSSIBILITY GIVEN
THE WIND FIELD SHOULD BEST CORES CAPITALIZE ON THE LIMITED
INSTABILITY.

SURFACE LOW DEEPENS TO 993 MB AS IT TRACKS NORTH OF LAKE SUPERIOR ON
FRIDAY.  THE OVERALL AMPLITUDE OF THIS SYSTEM CONTINUES TO FAVOR A
SLOWER DOWNSTREAM PROGRESSION OF THE MAIN HEIGHT FALL CENTER...WITH
THE CORRESPONDING COLD FRONTAL PASSAGE NOW EXPECTED EARLY FRIDAY
AFTERNOON.  A TRAILING PERIOD OF CVA AS THE STRONGER HEIGHT FALLS
COMMENCE AND COLD AIR ADVECTION ENSUES WILL SUSTAIN SCATTERED TO
NUMEROUS POST-FRONTAL SHOWER PRODUCTION LATE FRIDAY AND FRIDAY
NIGHT.

AMPLIFIED UPPER LEVEL TROUGH WILL BE SUSTAINED BY A 130 TO 140KT JET
THAT DIPS SOUTH OF THE GREAT LAKES INTO THE TENNESSEE VALLEY THROUGH
THE WEEKEND. THE UPPER LOW BECOMES CLOSED AT 500MB...BOTTOMING OUT
AROUND 538 DAM. EVEN AFTER SYNOPTIC RAIN ENDS ON SATURDAY...STEEP
LAPSE RATES IN PLACE WILL ALLOW FOR A 20 TO 30 PERCENT CHANCE FOR
RAIN SHOWERS EACH DAY IN THE EXTENDED PERIOD. STRONG GEOSTROPHIC
WIND COMPONENT WILL ALSO BE IN PLACE MOST OF THE PERIOD WITH DAYTIME
GUSTS OVER 20 MPH BEING COMMON.

MARINE...

SOUTHEAST WINDS WILL STEADILY INCREASE THURSDAY AND THURSDAY NIGHT
AS STRENGTHENING LOW PRESSURE TRACKS ACROSS LAKE SUPERIOR.  THIS
WILL RESULT IN A PERIOD OF GUSTY CONDITIONS FOR PORTIONS OF SOUTHERN
AND CENTRAL LAKE HURON BY LATE THURSDAY NIGHT AND EARLY FRIDAY.  THE
POTENTIAL EXISTS FOR SOME GUSTS OF UP TO 30 KNOTS...ALTHOUGH THE
ARRIVAL OF WARMER AIR WILL MAINTAIN A HIGHER DEGREE OF STABILITY
NEAR THE SURFACE.  THERE WILL BE A SLIGHT CHANCE FOR THUNDERSTORMS
AS WIDESPREAD SHOWERS MOVE THROUGH DURING THIS TIME.  A GUSTY
WESTERLY WIND FOR THE WEEKEND AS SEASONABLY COLD AIR OVERSPREADS THE
LAKES REGION.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....DG
SHORT TERM...CB
LONG TERM....MR/MM
MARINE.......MR


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







000
FXUS63 KDTX 020359
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1159 PM EDT WED OCT 1 2014


.AVIATION...

//DISCUSSION...

LIGHT SOUTHEAST FLOW CONTINUES TO FUNNEL LOW LEVEL MOISTURE INTO THE
AREA AND FOG/STRATUS IS ALREADY RE-FORMING LATE THIS EVENING WITH A
LARGER AREA OF IFR/LIFR CIGS ALSO SPREADING BACK WEST TOWARDS REGION
FROM ONTARIO/LAKE ERIE. WILL MAINTAIN IFR CIGS OVERNIGHT WITH VSBYS
ALSO FALLING INTO THE 1-2SM RANGE INTO EARLY THURSDAY MORNING. WITH
ANY LUCK...CIRRUS STREAMING INTO THE AREA WILL KEEP WIDESPREAD DENSE
FOG AT BAY OVERNIGHT. CONDITIONS WILL IMPROVE WITHIN INCREASED SOUTH
TO SOUTHEAST FLOW ON THURSDAY IN ADVANCE OF APPROACHING TROUGH. CIGS
WILL LIFT TO VFR...MAINLY FROM LEAD MOISTURE SHIFTING IN FROM THE
WEST WITH THIS NEXT SYSTEM.

//DTW THRESHOLD THREATS...

* MEDIUM TO HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET OVERNIGHT
INTO EARLY THURSDAY MORNING...WITH LOWER CONFIDENCE ON THURSDAY.

* LOW CONFIDENCE IN CEILINGS AOB 200 FT AND/OR VSBYS AOB 1/2SM FROM
ABOUT 06Z-14Z.

&&

.PREV DISCUSSION...ISSUED 354 PM EDT WED OCT 1 2014

SHORT TERM...TONIGHT

SOUTHEASTERN MICHIGAN WILL REMAIN UNDER THE SPELL OF THE STRONG
SURFACE ANTICYCLONE TONIGHT OVER PORTIONS OF EASTERN QUEBEC AND
CANADIAN MARITIMES WITH A SUBSTANTIAL SURFACE RIDGE EXTENDING BACK
INTO THE GREAT LAKES REGION. THIS FEATURE WILL CONTINUE TO DIRECT A
SOUTHEASTERLY LOW TROPOSPHERE FEED INTO THE STATE DESPITE A WEAK
MIDLEVEL RIDGE SLIDING OVERHEAD. THIS UPPER LEVEL RIDGE WILL
ESSENTIALLY CAUSE THE PATTERN LOCALLY TO REMAIN STAGNANT THROUGH THE
OVERNIGHT...DISALLOWING MUCH IN THE WAY OF ADVECTIONS OR AIRMASS
TURNOVER. CLOUD TRENDS THIS AFTERNOON HAVE BEEN SLUGGISH IN MANY
AREAS WITH A TRANSITION FROM STRATUS TO CUMULOFORM. THERE HAS BEEN A
RAPID CLEARING TREND OVER PORTIONS OF SOUTH CENTRAL LOWER MICHIGAN
BUT SUSPECT THIS TO SLOW DOWN AND NOT MAKE MUCH INROADS TO
SOUTHEASTERN MICHIGAN BEFORE SUNDOWN. INSTEAD...EXPECT VERTICAL
CLOUD CIRCULATIONS TO DEEPEN YET OVER THE NEXT 4 HOURS WHICH WILL
SUPPORT GREATER CONVECTIVE ELEMENT SPACING AND INTRODUCE GREATER
CLOUD SCALE SUBSIDENCE AND ENTRAINMENT OF DRY AIR ALOFT. THIS SHOULD
SET THE STAGES FOR A RAPID CLEARING TREND IN MANY AREAS POST SUNSET
WITH NOCTURNAL COOLING.

NAM AND LATEST HRRR NWP IS VERY SUPPORTIVE OF FOG TONIGHT WITH A
MUCH BETTER PROFILE FOR NEAR SURFACE SATURATION IN COMPARISON TO
YESTERDAY MORNING. GIVEN THE AFOREMENTIONED LACK OF ADVECTIONS ALONG
WITH THE CONTINUATION OF GREENUP ACROSS THE AREA...HIGH AMBIENT
MOISTURE IN THE BACKGROUND SHOULD SUPPORT FOG FAIRLY EARLY
TONIGHT...I.E. SHORTLY AFTER MIDNIGHT. EXPECTATIONS ARE FOR FOG TO
DEVELOP ACROSS PORTIONS OF ONTARIO...PORT HURON AND THE EASTERN
THUMB BEFORE SPREADING WESTWARD. MODELS ARE ALSO SHOWING A SIGNAL
THAT AREAS SOUTH AND EAST OF THE TERRAIN IN HIGHER SURFACE PRESSURE
AREAS COULD VERY WELL BE A FAVORABLE ZONE FOR FOG DEVELOPMENT. GIVEN
THERMODYNAMIC STRUCTURE...DENSE FOG WILL BE POSSIBLE. CONFIDENCE IS
NOT 100 PERCENT AS IT SELDOM IS...AND WILL GIVE LATER SHIFTS THE
FLEXIBILITY ON ANY POSSIBLE HEADLINE DECISIONS.

LONG TERM...

THE NORTHERN PORTION OF THE EXISTING LONGWAVE TROUGHING NOW
ENCOMPASSING MUCH OF THE WESTERN CONUS WILL UNDERGO SUBSTANTIAL
AMPLIFICATION OVER THE NEXT 48 HOURS.  THIS PROCESS WILL COMMENCE AS
STRONG SHORTWAVE ENERGY AND AN ATTENDANT 140 KT UPPER JET CORE
CURRENTLY OVER BRITISH COLUMBIA DIG INTO THE LOWER HEIGHT FIELD.
STRENGTHENING DYNAMICS ATTENDANT TO A LEAD WAVE UNDERCUTTING THE
AMPLIFYING TROUGH WILL BRING A PERIOD OF ACTIVE WEATHER TO END THE
WORK WEEK.  THE DEEPENING PROCESS WILL THEN LEAVE A CLOSED LOW
CONFIGURATION CENTERED JUST TO THE NORTH FOR THE UPCOMING
WEEKEND...SPELLING A CONSIDERABLY COLDER AND UNSETTLED PERIOD.

A DEEPER SOUTHWESTERLY FLOW TAKES HOLD ON THURSDAY AS THE
GRADUALLY EXPANDING HEIGHT FALLS NUDGE THE EXISTING UPPER RIDGE TO
THE EAST.  THIS PROCESS WILL MIX OUT ANY LINGERING FOG THROUGH LATE
MORNING...WITH THE ENSUING INCREASE IN MID LEVEL WARM AIR AND
THETA-E ADVECTION PROMPTING A STEADY THICKENING OF A HIGH BASED
CLOUD DECK DURING THE FIRST HALF OF THE DAY.  DESPITE THE WARMING
THERMAL PROFILE...A LINGERING SOUTHEAST SURFACE WIND AND LIMITED
MIXING DEPTH WILL MUTE THE OVERALL RESPONSE SLIGHTLY.  IN ACCORDANCE
WITH THE GOING FORECAST...WILL CONTINUE TO TEMPER EXPECTATIONS WITH
HIGHS OF LOW TO MID 70S.  TANGIBLE FORCING THROUGH THE DAYLIGHT
PERIOD REMAINS LESS DEFINED LOCALLY...THE AREA LARGELY REMOVED TO
THE EAST FROM THE MAIN CORRIDOR OF ASCENT LOCKED ONTO THE
THETA-E RIDGE AND PRIMARY TRAJECTORY OF ANY LOWER AMPLITUDE SHORTWAVE
ENERGY FUNNELING THROUGH THE MEAN SW FLOW.  THERE REMAINS THE
POTENTIAL FOR THIS AXIS TO CREEP FAR ENOUGH EAST TO SUPPORT SOME
LIGHT SHOWER DEVELOPMENT...PARTICULARLY ACROSS THE TRI-CITIES.  LOW
CHANCE POPS REMAIN APPROPRIATE FOR THIS AREA GIVEN THE HIGH DEGREE
OF UNCERTAINTY.

THE INCREASING INTERACTION BETWEEN THE AFOREMENTIONED SOUTHERN
WAVE EJECTING NORTHEAST OUT OF THE SOUTHERN PLAINS AND THE DEEPENING
LOW ACROSS THE DAKOTAS WILL PROMPT RAPID SURFACE CYCLOGENESIS AND A
STRENGTHENING OF THE ATTENDANT COLD FRONT UPSTREAM BY THURSDAY
NIGHT.  THE DOWNSTREAM PROPAGATION OF A STRENGTHENING WIND FIELD
/50 KTS AT 850MB/ EMBEDDED WITHIN THE WARM SECTOR AND AT THE EDGE OF
THE INBOUND LOWER HEIGHT FIELD WILL LIKELY PROMOTE AN EXPANSION IN
PRECIPITATION COVERAGE THROUGHOUT THE MIDWEST BY LATE THURSDAY.
THIS FORCING REMAINS FORECAST TO TRACK THROUGH SE MICHIGAN LATE
THURSDAY NIGHT AND EARLY FRIDAY...A CORRESPONDING STEADY INCREASE IN
PRECIPITATION CHANCES COMMENCING DURING THIS TIME.  DEEPEST ASCENT
IN PLACE DURING THE FIRST HALF OF FRIDAY...A PERIOD OF SOLID UPPER
DIVERGENCE AND CVA WORKING INTO A MOISTENING PRE-FRONTAL
ENVIRONMENT.  EXISTING MID LEVEL INSTABILITY CERTAINLY SUFFICIENT TO
SUPPORT A THUNDER MENTION...A FEW STRONGER GUSTS A POSSIBILITY GIVEN
THE WIND FIELD SHOULD BEST CORES CAPITALIZE ON THE LIMITED
INSTABILITY.

SURFACE LOW DEEPENS TO 993 MB AS IT TRACKS NORTH OF LAKE SUPERIOR ON
FRIDAY.  THE OVERALL AMPLITUDE OF THIS SYSTEM CONTINUES TO FAVOR A
SLOWER DOWNSTREAM PROGRESSION OF THE MAIN HEIGHT FALL CENTER...WITH
THE CORRESPONDING COLD FRONTAL PASSAGE NOW EXPECTED EARLY FRIDAY
AFTERNOON.  A TRAILING PERIOD OF CVA AS THE STRONGER HEIGHT FALLS
COMMENCE AND COLD AIR ADVECTION ENSUES WILL SUSTAIN SCATTERED TO
NUMEROUS POST-FRONTAL SHOWER PRODUCTION LATE FRIDAY AND FRIDAY
NIGHT.

AMPLIFIED UPPER LEVEL TROUGH WILL BE SUSTAINED BY A 130 TO 140KT JET
THAT DIPS SOUTH OF THE GREAT LAKES INTO THE TENNESSEE VALLEY THROUGH
THE WEEKEND. THE UPPER LOW BECOMES CLOSED AT 500MB...BOTTOMING OUT
AROUND 538 DAM. EVEN AFTER SYNOPTIC RAIN ENDS ON SATURDAY...STEEP
LAPSE RATES IN PLACE WILL ALLOW FOR A 20 TO 30 PERCENT CHANCE FOR
RAIN SHOWERS EACH DAY IN THE EXTENDED PERIOD. STRONG GEOSTROPHIC
WIND COMPONENT WILL ALSO BE IN PLACE MOST OF THE PERIOD WITH DAYTIME
GUSTS OVER 20 MPH BEING COMMON.

MARINE...

SOUTHEAST WINDS WILL STEADILY INCREASE THURSDAY AND THURSDAY NIGHT
AS STRENGTHENING LOW PRESSURE TRACKS ACROSS LAKE SUPERIOR.  THIS
WILL RESULT IN A PERIOD OF GUSTY CONDITIONS FOR PORTIONS OF SOUTHERN
AND CENTRAL LAKE HURON BY LATE THURSDAY NIGHT AND EARLY FRIDAY.  THE
POTENTIAL EXISTS FOR SOME GUSTS OF UP TO 30 KNOTS...ALTHOUGH THE
ARRIVAL OF WARMER AIR WILL MAINTAIN A HIGHER DEGREE OF STABILITY
NEAR THE SURFACE.  THERE WILL BE A SLIGHT CHANCE FOR THUNDERSTORMS
AS WIDESPREAD SHOWERS MOVE THROUGH DURING THIS TIME.  A GUSTY
WESTERLY WIND FOR THE WEEKEND AS SEASONABLY COLD AIR OVERSPREADS THE
LAKES REGION.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....DG
SHORT TERM...CB
LONG TERM....MR/MM
MARINE.......MR


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








000
FXUS63 KDTX 012334
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
734 PM EDT WED OCT 1 2014


.AVIATION...

//DISCUSSION...

RADIATIONAL COOLING WILL BE DECENT TONIGHT NOW THAT SKIES HAVE
BECOME PARTLY CLOUDY. THIS...COMBINED WITH CONTINUED LIGHT FLOW FROM
THE SOUTHEAST WILL MOST LIKELY PROMOTE SOME FOG DEVELOPMENT AFTER
MIDNIGHT INTO EARLY THURSDAY MORNING. CONFIDENCE IN COVERAGE AND
TIMING REMAIN LOW AT THIS POINT. ANY FOG/LOW STRATUS THAT DOES
DEVELOP WILL DISSIPATE AS LOWER/MID VFR CIGS BETWEEN 6-12KFT MOVE
INTO THE AREA IN ADVANCE OF APPROACHING TROUGH.

//DTW THRESHOLD THREATS...

* LOW CONFIDENCE IN CEILINGS AOB 200 FT AND/OR VSBYS AOB 1/2SM AFTER
2 AM.

&&

.PREV DISCUSSION...ISSUED 354 PM EDT WED OCT 1 2014

SHORT TERM...TONIGHT

SOUTHEASTERN MICHIGAN WILL REMAIN UNDER THE SPELL OF THE STRONG
SURFACE ANTICYCLONE TONIGHT OVER PORTIONS OF EASTERN QUEBEC AND
CANADIAN MARITIMES WITH A SUBSTANTIAL SURFACE RIDGE EXTENDING BACK
INTO THE GREAT LAKES REGION. THIS FEATURE WILL CONTINUE TO DIRECT A
SOUTHEASTERLY LOW TROPOSPHERE FEED INTO THE STATE DESPITE A WEAK
MIDLEVEL RIDGE SLIDING OVERHEAD. THIS UPPER LEVEL RIDGE WILL
ESSENTIALLY CAUSE THE PATTERN LOCALLY TO REMAIN STAGNANT THROUGH THE
OVERNIGHT...DISALLOWING MUCH IN THE WAY OF ADVECTIONS OR AIRMASS
TURNOVER. CLOUD TRENDS THIS AFTERNOON HAVE BEEN SLUGGISH IN MANY
AREAS WITH A TRANSITION FROM STRATUS TO CUMULOFORM. THERE HAS BEEN A
RAPID CLEARING TREND OVER PORTIONS OF SOUTH CENTRAL LOWER MICHIGAN
BUT SUSPECT THIS TO SLOW DOWN AND NOT MAKE MUCH INROADS TO
SOUTHEASTERN MICHIGAN BEFORE SUNDOWN. INSTEAD...EXPECT VERTICAL
CLOUD CIRCULATIONS TO DEEPEN YET OVER THE NEXT 4 HOURS WHICH WILL
SUPPORT GREATER CONVECTIVE ELEMENT SPACING AND INTRODUCE GREATER
CLOUD SCALE SUBSIDENCE AND ENTRAINMENT OF DRY AIR ALOFT. THIS SHOULD
SET THE STAGES FOR A RAPID CLEARING TREND IN MANY AREAS POST SUNSET
WITH NOCTURNAL COOLING.

NAM AND LATEST HRRR NWP IS VERY SUPPORTIVE OF FOG TONIGHT WITH A
MUCH BETTER PROFILE FOR NEAR SURFACE SATURATION IN COMPARISON TO
YESTERDAY MORNING. GIVEN THE AFOREMENTIONED LACK OF ADVECTIONS ALONG
WITH THE CONTINUATION OF GREENUP ACROSS THE AREA...HIGH AMBIENT
MOISTURE IN THE BACKGROUND SHOULD SUPPORT FOG FAIRLY EARLY
TONIGHT...I.E. SHORTLY AFTER MIDNIGHT. EXPECTATIONS ARE FOR FOG TO
DEVELOP ACROSS PORTIONS OF ONTARIO...PORT HURON AND THE EASTERN
THUMB BEFORE SPREADING WESTWARD. MODELS ARE ALSO SHOWING A SIGNAL
THAT AREAS SOUTH AND EAST OF THE TERRAIN IN HIGHER SURFACE PRESSURE
AREAS COULD VERY WELL BE A FAVORABLE ZONE FOR FOG DEVELOPMENT. GIVEN
THERMODYNAMIC STRUCTURE...DENSE FOG WILL BE POSSIBLE. CONFIDENCE IS
NOT 100 PERCENT AS IT SELDOM IS...AND WILL GIVE LATER SHIFTS THE
FLEXIBILITY ON ANY POSSIBLE HEADLINE DECISIONS.

LONG TERM...

THE NORTHERN PORTION OF THE EXISTING LONGWAVE TROUGHING NOW
ENCOMPASSING MUCH OF THE WESTERN CONUS WILL UNDERGO SUBSTANTIAL
AMPLIFICATION OVER THE NEXT 48 HOURS.  THIS PROCESS WILL COMMENCE AS
STRONG SHORTWAVE ENERGY AND AN ATTENDANT 140 KT UPPER JET CORE
CURRENTLY OVER BRITISH COLUMBIA DIG INTO THE LOWER HEIGHT FIELD.
STRENGTHENING DYNAMICS ATTENDANT TO A LEAD WAVE UNDERCUTTING THE
AMPLIFYING TROUGH WILL BRING A PERIOD OF ACTIVE WEATHER TO END THE
WORK WEEK.  THE DEEPENING PROCESS WILL THEN LEAVE A CLOSED LOW
CONFIGURATION CENTERED JUST TO THE NORTH FOR THE UPCOMING
WEEKEND...SPELLING A CONSIDERABLY COLDER AND UNSETTLED PERIOD.

A DEEPER SOUTHWESTERLY FLOW TAKES HOLD ON THURSDAY AS THE
GRADUALLY EXPANDING HEIGHT FALLS NUDGE THE EXISTING UPPER RIDGE TO
THE EAST.  THIS PROCESS WILL MIX OUT ANY LINGERING FOG THROUGH LATE
MORNING...WITH THE ENSUING INCREASE IN MID LEVEL WARM AIR AND
THETA-E ADVECTION PROMPTING A STEADY THICKENING OF A HIGH BASED
CLOUD DECK DURING THE FIRST HALF OF THE DAY.  DESPITE THE WARMING
THERMAL PROFILE...A LINGERING SOUTHEAST SURFACE WIND AND LIMITED
MIXING DEPTH WILL MUTE THE OVERALL RESPONSE SLIGHTLY.  IN ACCORDANCE
WITH THE GOING FORECAST...WILL CONTINUE TO TEMPER EXPECTATIONS WITH
HIGHS OF LOW TO MID 70S.  TANGIBLE FORCING THROUGH THE DAYLIGHT
PERIOD REMAINS LESS DEFINED LOCALLY...THE AREA LARGELY REMOVED TO
THE EAST FROM THE MAIN CORRIDOR OF ASCENT LOCKED ONTO THE
THETA-E RIDGE AND PRIMARY TRAJECTORY OF ANY LOWER AMPLITUDE SHORTWAVE
ENERGY FUNNELING THROUGH THE MEAN SW FLOW.  THERE REMAINS THE
POTENTIAL FOR THIS AXIS TO CREEP FAR ENOUGH EAST TO SUPPORT SOME
LIGHT SHOWER DEVELOPMENT...PARTICULARLY ACROSS THE TRI-CITIES.  LOW
CHANCE POPS REMAIN APPROPRIATE FOR THIS AREA GIVEN THE HIGH DEGREE
OF UNCERTAINTY.

THE INCREASING INTERACTION BETWEEN THE AFOREMENTIONED SOUTHERN
WAVE EJECTING NORTHEAST OUT OF THE SOUTHERN PLAINS AND THE DEEPENING
LOW ACROSS THE DAKOTAS WILL PROMPT RAPID SURFACE CYCLOGENESIS AND A
STRENGTHENING OF THE ATTENDANT COLD FRONT UPSTREAM BY THURSDAY
NIGHT.  THE DOWNSTREAM PROPAGATION OF A STRENGTHENING WIND FIELD
/50 KTS AT 850MB/ EMBEDDED WITHIN THE WARM SECTOR AND AT THE EDGE OF
THE INBOUND LOWER HEIGHT FIELD WILL LIKELY PROMOTE AN EXPANSION IN
PRECIPITATION COVERAGE THROUGHOUT THE MIDWEST BY LATE THURSDAY.
THIS FORCING REMAINS FORECAST TO TRACK THROUGH SE MICHIGAN LATE
THURSDAY NIGHT AND EARLY FRIDAY...A CORRESPONDING STEADY INCREASE IN
PRECIPITATION CHANCES COMMENCING DURING THIS TIME.  DEEPEST ASCENT
IN PLACE DURING THE FIRST HALF OF FRIDAY...A PERIOD OF SOLID UPPER
DIVERGENCE AND CVA WORKING INTO A MOISTENING PRE-FRONTAL
ENVIRONMENT.  EXISTING MID LEVEL INSTABILITY CERTAINLY SUFFICIENT TO
SUPPORT A THUNDER MENTION...A FEW STRONGER GUSTS A POSSIBILITY GIVEN
THE WIND FIELD SHOULD BEST CORES CAPITALIZE ON THE LIMITED
INSTABILITY.

SURFACE LOW DEEPENS TO 993 MB AS IT TRACKS NORTH OF LAKE SUPERIOR ON
FRIDAY.  THE OVERALL AMPLITUDE OF THIS SYSTEM CONTINUES TO FAVOR A
SLOWER DOWNSTREAM PROGRESSION OF THE MAIN HEIGHT FALL CENTER...WITH
THE CORRESPONDING COLD FRONTAL PASSAGE NOW EXPECTED EARLY FRIDAY
AFTERNOON.  A TRAILING PERIOD OF CVA AS THE STRONGER HEIGHT FALLS
COMMENCE AND COLD AIR ADVECTION ENSUES WILL SUSTAIN SCATTERED TO
NUMEROUS POST-FRONTAL SHOWER PRODUCTION LATE FRIDAY AND FRIDAY
NIGHT.

AMPLIFIED UPPER LEVEL TROUGH WILL BE SUSTAINED BY A 130 TO 140KT JET
THAT DIPS SOUTH OF THE GREAT LAKES INTO THE TENNESSEE VALLEY THROUGH
THE WEEKEND. THE UPPER LOW BECOMES CLOSED AT 500MB...BOTTOMING OUT
AROUND 538 DAM. EVEN AFTER SYNOPTIC RAIN ENDS ON SATURDAY...STEEP
LAPSE RATES IN PLACE WILL ALLOW FOR A 20 TO 30 PERCENT CHANCE FOR
RAIN SHOWERS EACH DAY IN THE EXTENDED PERIOD. STRONG GEOSTROPHIC
WIND COMPONENT WILL ALSO BE IN PLACE MOST OF THE PERIOD WITH DAYTIME
GUSTS OVER 20 MPH BEING COMMON.

MARINE...

SOUTHEAST WINDS WILL STEADILY INCREASE THURSDAY AND THURSDAY NIGHT
AS STRENGTHENING LOW PRESSURE TRACKS ACROSS LAKE SUPERIOR.  THIS
WILL RESULT IN A PERIOD OF GUSTY CONDITIONS FOR PORTIONS OF SOUTHERN
AND CENTRAL LAKE HURON BY LATE THURSDAY NIGHT AND EARLY FRIDAY.  THE
POTENTIAL EXISTS FOR SOME GUSTS OF UP TO 30 KNOTS...ALTHOUGH THE
ARRIVAL OF WARMER AIR WILL MAINTAIN A HIGHER DEGREE OF STABILITY
NEAR THE SURFACE.  THERE WILL BE A SLIGHT CHANCE FOR THUNDERSTORMS
AS WIDESPREAD SHOWERS MOVE THROUGH DURING THIS TIME.  A GUSTY
WESTERLY WIND FOR THE WEEKEND AS SEASONABLY COLD AIR OVERSPREADS THE
LAKES REGION.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....DG
SHORT TERM...CB
LONG TERM....MR/MM
MARINE.......MR


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








000
FXUS63 KDTX 012334
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
734 PM EDT WED OCT 1 2014


.AVIATION...

//DISCUSSION...

RADIATIONAL COOLING WILL BE DECENT TONIGHT NOW THAT SKIES HAVE
BECOME PARTLY CLOUDY. THIS...COMBINED WITH CONTINUED LIGHT FLOW FROM
THE SOUTHEAST WILL MOST LIKELY PROMOTE SOME FOG DEVELOPMENT AFTER
MIDNIGHT INTO EARLY THURSDAY MORNING. CONFIDENCE IN COVERAGE AND
TIMING REMAIN LOW AT THIS POINT. ANY FOG/LOW STRATUS THAT DOES
DEVELOP WILL DISSIPATE AS LOWER/MID VFR CIGS BETWEEN 6-12KFT MOVE
INTO THE AREA IN ADVANCE OF APPROACHING TROUGH.

//DTW THRESHOLD THREATS...

* LOW CONFIDENCE IN CEILINGS AOB 200 FT AND/OR VSBYS AOB 1/2SM AFTER
2 AM.

&&

.PREV DISCUSSION...ISSUED 354 PM EDT WED OCT 1 2014

SHORT TERM...TONIGHT

SOUTHEASTERN MICHIGAN WILL REMAIN UNDER THE SPELL OF THE STRONG
SURFACE ANTICYCLONE TONIGHT OVER PORTIONS OF EASTERN QUEBEC AND
CANADIAN MARITIMES WITH A SUBSTANTIAL SURFACE RIDGE EXTENDING BACK
INTO THE GREAT LAKES REGION. THIS FEATURE WILL CONTINUE TO DIRECT A
SOUTHEASTERLY LOW TROPOSPHERE FEED INTO THE STATE DESPITE A WEAK
MIDLEVEL RIDGE SLIDING OVERHEAD. THIS UPPER LEVEL RIDGE WILL
ESSENTIALLY CAUSE THE PATTERN LOCALLY TO REMAIN STAGNANT THROUGH THE
OVERNIGHT...DISALLOWING MUCH IN THE WAY OF ADVECTIONS OR AIRMASS
TURNOVER. CLOUD TRENDS THIS AFTERNOON HAVE BEEN SLUGGISH IN MANY
AREAS WITH A TRANSITION FROM STRATUS TO CUMULOFORM. THERE HAS BEEN A
RAPID CLEARING TREND OVER PORTIONS OF SOUTH CENTRAL LOWER MICHIGAN
BUT SUSPECT THIS TO SLOW DOWN AND NOT MAKE MUCH INROADS TO
SOUTHEASTERN MICHIGAN BEFORE SUNDOWN. INSTEAD...EXPECT VERTICAL
CLOUD CIRCULATIONS TO DEEPEN YET OVER THE NEXT 4 HOURS WHICH WILL
SUPPORT GREATER CONVECTIVE ELEMENT SPACING AND INTRODUCE GREATER
CLOUD SCALE SUBSIDENCE AND ENTRAINMENT OF DRY AIR ALOFT. THIS SHOULD
SET THE STAGES FOR A RAPID CLEARING TREND IN MANY AREAS POST SUNSET
WITH NOCTURNAL COOLING.

NAM AND LATEST HRRR NWP IS VERY SUPPORTIVE OF FOG TONIGHT WITH A
MUCH BETTER PROFILE FOR NEAR SURFACE SATURATION IN COMPARISON TO
YESTERDAY MORNING. GIVEN THE AFOREMENTIONED LACK OF ADVECTIONS ALONG
WITH THE CONTINUATION OF GREENUP ACROSS THE AREA...HIGH AMBIENT
MOISTURE IN THE BACKGROUND SHOULD SUPPORT FOG FAIRLY EARLY
TONIGHT...I.E. SHORTLY AFTER MIDNIGHT. EXPECTATIONS ARE FOR FOG TO
DEVELOP ACROSS PORTIONS OF ONTARIO...PORT HURON AND THE EASTERN
THUMB BEFORE SPREADING WESTWARD. MODELS ARE ALSO SHOWING A SIGNAL
THAT AREAS SOUTH AND EAST OF THE TERRAIN IN HIGHER SURFACE PRESSURE
AREAS COULD VERY WELL BE A FAVORABLE ZONE FOR FOG DEVELOPMENT. GIVEN
THERMODYNAMIC STRUCTURE...DENSE FOG WILL BE POSSIBLE. CONFIDENCE IS
NOT 100 PERCENT AS IT SELDOM IS...AND WILL GIVE LATER SHIFTS THE
FLEXIBILITY ON ANY POSSIBLE HEADLINE DECISIONS.

LONG TERM...

THE NORTHERN PORTION OF THE EXISTING LONGWAVE TROUGHING NOW
ENCOMPASSING MUCH OF THE WESTERN CONUS WILL UNDERGO SUBSTANTIAL
AMPLIFICATION OVER THE NEXT 48 HOURS.  THIS PROCESS WILL COMMENCE AS
STRONG SHORTWAVE ENERGY AND AN ATTENDANT 140 KT UPPER JET CORE
CURRENTLY OVER BRITISH COLUMBIA DIG INTO THE LOWER HEIGHT FIELD.
STRENGTHENING DYNAMICS ATTENDANT TO A LEAD WAVE UNDERCUTTING THE
AMPLIFYING TROUGH WILL BRING A PERIOD OF ACTIVE WEATHER TO END THE
WORK WEEK.  THE DEEPENING PROCESS WILL THEN LEAVE A CLOSED LOW
CONFIGURATION CENTERED JUST TO THE NORTH FOR THE UPCOMING
WEEKEND...SPELLING A CONSIDERABLY COLDER AND UNSETTLED PERIOD.

A DEEPER SOUTHWESTERLY FLOW TAKES HOLD ON THURSDAY AS THE
GRADUALLY EXPANDING HEIGHT FALLS NUDGE THE EXISTING UPPER RIDGE TO
THE EAST.  THIS PROCESS WILL MIX OUT ANY LINGERING FOG THROUGH LATE
MORNING...WITH THE ENSUING INCREASE IN MID LEVEL WARM AIR AND
THETA-E ADVECTION PROMPTING A STEADY THICKENING OF A HIGH BASED
CLOUD DECK DURING THE FIRST HALF OF THE DAY.  DESPITE THE WARMING
THERMAL PROFILE...A LINGERING SOUTHEAST SURFACE WIND AND LIMITED
MIXING DEPTH WILL MUTE THE OVERALL RESPONSE SLIGHTLY.  IN ACCORDANCE
WITH THE GOING FORECAST...WILL CONTINUE TO TEMPER EXPECTATIONS WITH
HIGHS OF LOW TO MID 70S.  TANGIBLE FORCING THROUGH THE DAYLIGHT
PERIOD REMAINS LESS DEFINED LOCALLY...THE AREA LARGELY REMOVED TO
THE EAST FROM THE MAIN CORRIDOR OF ASCENT LOCKED ONTO THE
THETA-E RIDGE AND PRIMARY TRAJECTORY OF ANY LOWER AMPLITUDE SHORTWAVE
ENERGY FUNNELING THROUGH THE MEAN SW FLOW.  THERE REMAINS THE
POTENTIAL FOR THIS AXIS TO CREEP FAR ENOUGH EAST TO SUPPORT SOME
LIGHT SHOWER DEVELOPMENT...PARTICULARLY ACROSS THE TRI-CITIES.  LOW
CHANCE POPS REMAIN APPROPRIATE FOR THIS AREA GIVEN THE HIGH DEGREE
OF UNCERTAINTY.

THE INCREASING INTERACTION BETWEEN THE AFOREMENTIONED SOUTHERN
WAVE EJECTING NORTHEAST OUT OF THE SOUTHERN PLAINS AND THE DEEPENING
LOW ACROSS THE DAKOTAS WILL PROMPT RAPID SURFACE CYCLOGENESIS AND A
STRENGTHENING OF THE ATTENDANT COLD FRONT UPSTREAM BY THURSDAY
NIGHT.  THE DOWNSTREAM PROPAGATION OF A STRENGTHENING WIND FIELD
/50 KTS AT 850MB/ EMBEDDED WITHIN THE WARM SECTOR AND AT THE EDGE OF
THE INBOUND LOWER HEIGHT FIELD WILL LIKELY PROMOTE AN EXPANSION IN
PRECIPITATION COVERAGE THROUGHOUT THE MIDWEST BY LATE THURSDAY.
THIS FORCING REMAINS FORECAST TO TRACK THROUGH SE MICHIGAN LATE
THURSDAY NIGHT AND EARLY FRIDAY...A CORRESPONDING STEADY INCREASE IN
PRECIPITATION CHANCES COMMENCING DURING THIS TIME.  DEEPEST ASCENT
IN PLACE DURING THE FIRST HALF OF FRIDAY...A PERIOD OF SOLID UPPER
DIVERGENCE AND CVA WORKING INTO A MOISTENING PRE-FRONTAL
ENVIRONMENT.  EXISTING MID LEVEL INSTABILITY CERTAINLY SUFFICIENT TO
SUPPORT A THUNDER MENTION...A FEW STRONGER GUSTS A POSSIBILITY GIVEN
THE WIND FIELD SHOULD BEST CORES CAPITALIZE ON THE LIMITED
INSTABILITY.

SURFACE LOW DEEPENS TO 993 MB AS IT TRACKS NORTH OF LAKE SUPERIOR ON
FRIDAY.  THE OVERALL AMPLITUDE OF THIS SYSTEM CONTINUES TO FAVOR A
SLOWER DOWNSTREAM PROGRESSION OF THE MAIN HEIGHT FALL CENTER...WITH
THE CORRESPONDING COLD FRONTAL PASSAGE NOW EXPECTED EARLY FRIDAY
AFTERNOON.  A TRAILING PERIOD OF CVA AS THE STRONGER HEIGHT FALLS
COMMENCE AND COLD AIR ADVECTION ENSUES WILL SUSTAIN SCATTERED TO
NUMEROUS POST-FRONTAL SHOWER PRODUCTION LATE FRIDAY AND FRIDAY
NIGHT.

AMPLIFIED UPPER LEVEL TROUGH WILL BE SUSTAINED BY A 130 TO 140KT JET
THAT DIPS SOUTH OF THE GREAT LAKES INTO THE TENNESSEE VALLEY THROUGH
THE WEEKEND. THE UPPER LOW BECOMES CLOSED AT 500MB...BOTTOMING OUT
AROUND 538 DAM. EVEN AFTER SYNOPTIC RAIN ENDS ON SATURDAY...STEEP
LAPSE RATES IN PLACE WILL ALLOW FOR A 20 TO 30 PERCENT CHANCE FOR
RAIN SHOWERS EACH DAY IN THE EXTENDED PERIOD. STRONG GEOSTROPHIC
WIND COMPONENT WILL ALSO BE IN PLACE MOST OF THE PERIOD WITH DAYTIME
GUSTS OVER 20 MPH BEING COMMON.

MARINE...

SOUTHEAST WINDS WILL STEADILY INCREASE THURSDAY AND THURSDAY NIGHT
AS STRENGTHENING LOW PRESSURE TRACKS ACROSS LAKE SUPERIOR.  THIS
WILL RESULT IN A PERIOD OF GUSTY CONDITIONS FOR PORTIONS OF SOUTHERN
AND CENTRAL LAKE HURON BY LATE THURSDAY NIGHT AND EARLY FRIDAY.  THE
POTENTIAL EXISTS FOR SOME GUSTS OF UP TO 30 KNOTS...ALTHOUGH THE
ARRIVAL OF WARMER AIR WILL MAINTAIN A HIGHER DEGREE OF STABILITY
NEAR THE SURFACE.  THERE WILL BE A SLIGHT CHANCE FOR THUNDERSTORMS
AS WIDESPREAD SHOWERS MOVE THROUGH DURING THIS TIME.  A GUSTY
WESTERLY WIND FOR THE WEEKEND AS SEASONABLY COLD AIR OVERSPREADS THE
LAKES REGION.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....DG
SHORT TERM...CB
LONG TERM....MR/MM
MARINE.......MR


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







000
FXUS63 KDTX 011954
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
354 PM EDT WED OCT 1 2014

.SHORT TERM...TONIGHT

SOUTHEASTERN MICHIGAN WILL REMAIN UNDER THE SPELL OF THE STRONG
SURFACE ANTICYCLONE TONIGHT OVER PORTIONS OF EASTERN QUEBEC AND
CANADIAN MARITIMES WITH A SUBSTANTIAL SURFACE RIDGE EXTENDING BACK
INTO THE GREAT LAKES REGION. THIS FEATURE WILL CONTINUE TO DIRECT A
SOUTHEASTERLY LOW TROPOSPHERE FEED INTO THE STATE DESPITE A WEAK
MIDLEVEL RIDGE SLIDING OVERHEAD. THIS UPPER LEVEL RIDGE WILL
ESSENTIALLY CAUSE THE PATTERN LOCALLY TO REMAIN STAGNANT THROUGH THE
OVERNIGHT...DISALLOWING MUCH IN THE WAY OF ADVECTIONS OR AIRMASS
TURNOVER. CLOUD TRENDS THIS AFTERNOON HAVE BEEN SLUGGISH IN MANY
AREAS WITH A TRANSITION FROM STRATUS TO CUMULOFORM. THERE HAS BEEN A
RAPID CLEARING TREND OVER PORTIONS OF SOUTH CENTRAL LOWER MICHIGAN
BUT SUSPECT THIS TO SLOW DOWN AND NOT MAKE MUCH INROADS TO
SOUTHEASTERN MICHIGAN BEFORE SUNDOWN. INSTEAD...EXPECT VERTICAL
CLOUD CIRCULATIONS TO DEEPEN YET OVER THE NEXT 4 HOURS WHICH WILL
SUPPORT GREATER CONVECTIVE ELEMENT SPACING AND INTRODUCE GREATER
CLOUD SCALE SUBSIDENCE AND ENTRAINMENT OF DRY AIR ALOFT. THIS SHOULD
SET THE STAGES FOR A RAPID CLEARING TREND IN MANY AREAS POST SUNSET
WITH NOCTURNAL COOLING.

NAM AND LATEST HRRR NWP IS VERY SUPPORTIVE OF FOG TONIGHT WITH A
MUCH BETTER PROFILE FOR NEAR SURFACE SATURATION IN COMPARISON TO
YESTERDAY MORNING. GIVEN THE AFOREMENTIONED LACK OF ADVECTIONS ALONG
WITH THE CONTINUATION OF GREENUP ACROSS THE AREA...HIGH AMBIENT
MOISTURE IN THE BACKGROUND SHOULD SUPPORT FOG FAIRLY EARLY
TONIGHT...I.E. SHORTLY AFTER MIDNIGHT. EXPECTATIONS ARE FOR FOG TO
DEVELOP ACROSS PORTIONS OF ONTARIO...PORT HURON AND THE EASTERN
THUMB BEFORE SPREADING WESTWARD. MODELS ARE ALSO SHOWING A SIGNAL
THAT AREAS SOUTH AND EAST OF THE TERRAIN IN HIGHER SURFACE PRESSURE
AREAS COULD VERY WELL BE A FAVORABLE ZONE FOR FOG DEVELOPMENT. GIVEN
THERMODYNAMIC STRUCTURE...DENSE FOG WILL BE POSSIBLE. CONFIDENCE IS
NOT 100 PERCENT AS IT SELDOM IS...AND WILL GIVE LATER SHIFTS THE
FLEXIBILITY ON ANY POSSIBLE HEADLINE DECISIONS.

&&

.LONG TERM...

THE NORTHERN PORTION OF THE EXISTING LONGWAVE TROUGHING NOW
ENCOMPASSING MUCH OF THE WESTERN CONUS WILL UNDERGO SUBSTANTIAL
AMPLIFICATION OVER THE NEXT 48 HOURS.  THIS PROCESS WILL COMMENCE AS
STRONG SHORTWAVE ENERGY AND AN ATTENDANT 140 KT UPPER JET CORE
CURRENTLY OVER BRITISH COLUMBIA DIG INTO THE LOWER HEIGHT FIELD.
STRENGTHENING DYNAMICS ATTENDANT TO A LEAD WAVE UNDERCUTTING THE
AMPLIFYING TROUGH WILL BRING A PERIOD OF ACTIVE WEATHER TO END THE
WORK WEEK.  THE DEEPENING PROCESS WILL THEN LEAVE A CLOSED LOW
CONFIGURATION CENTERED JUST TO THE NORTH FOR THE UPCOMING
WEEKEND...SPELLING A CONSIDERABLY COLDER AND UNSETTLED PERIOD.

A DEEPER SOUTHWESTERLY FLOW TAKES HOLD ON THURSDAY AS THE
GRADUALLY EXPANDING HEIGHT FALLS NUDGE THE EXISTING UPPER RIDGE TO
THE EAST.  THIS PROCESS WILL MIX OUT ANY LINGERING FOG THROUGH LATE
MORNING...WITH THE ENSUING INCREASE IN MID LEVEL WARM AIR AND
THETA-E ADVECTION PROMPTING A STEADY THICKENING OF A HIGH BASED
CLOUD DECK DURING THE FIRST HALF OF THE DAY.  DESPITE THE WARMING
THERMAL PROFILE...A LINGERING SOUTHEAST SURFACE WIND AND LIMITED
MIXING DEPTH WILL MUTE THE OVERALL RESPONSE SLIGHTLY.  IN ACCORDANCE
WITH THE GOING FORECAST...WILL CONTINUE TO TEMPER EXPECTATIONS WITH
HIGHS OF LOW TO MID 70S.  TANGIBLE FORCING THROUGH THE DAYLIGHT
PERIOD REMAINS LESS DEFINED LOCALLY...THE AREA LARGELY REMOVED TO
THE EAST FROM THE MAIN CORRIDOR OF ASCENT LOCKED ONTO THE
THETA-E RIDGE AND PRIMARY TRAJECTORY OF ANY LOWER AMPLITUDE SHORTWAVE
ENERGY FUNNELING THROUGH THE MEAN SW FLOW.  THERE REMAINS THE
POTENTIAL FOR THIS AXIS TO CREEP FAR ENOUGH EAST TO SUPPORT SOME
LIGHT SHOWER DEVELOPMENT...PARTICULARLY ACROSS THE TRI-CITIES.  LOW
CHANCE POPS REMAIN APPROPRIATE FOR THIS AREA GIVEN THE HIGH DEGREE
OF UNCERTAINTY.

THE INCREASING INTERACTION BETWEEN THE AFOREMENTIONED SOUTHERN
WAVE EJECTING NORTHEAST OUT OF THE SOUTHERN PLAINS AND THE DEEPENING
LOW ACROSS THE DAKOTAS WILL PROMPT RAPID SURFACE CYCLOGENESIS AND A
STRENGTHENING OF THE ATTENDANT COLD FRONT UPSTREAM BY THURSDAY
NIGHT.  THE DOWNSTREAM PROPAGATION OF A STRENGTHENING WIND FIELD
/50 KTS AT 850MB/ EMBEDDED WITHIN THE WARM SECTOR AND AT THE EDGE OF
THE INBOUND LOWER HEIGHT FIELD WILL LIKELY PROMOTE AN EXPANSION IN
PRECIPITATION COVERAGE THROUGHOUT THE MIDWEST BY LATE THURSDAY.
THIS FORCING REMAINS FORECAST TO TRACK THROUGH SE MICHIGAN LATE
THURSDAY NIGHT AND EARLY FRIDAY...A CORRESPONDING STEADY INCREASE IN
PRECIPITATION CHANCES COMMENCING DURING THIS TIME.  DEEPEST ASCENT
IN PLACE DURING THE FIRST HALF OF FRIDAY...A PERIOD OF SOLID UPPER
DIVERGENCE AND CVA WORKING INTO A MOISTENING PRE-FRONTAL
ENVIRONMENT.  EXISTING MID LEVEL INSTABILITY CERTAINLY SUFFICIENT TO
SUPPORT A THUNDER MENTION...A FEW STRONGER GUSTS A POSSIBILITY GIVEN
THE WIND FIELD SHOULD BEST CORES CAPITALIZE ON THE LIMITED
INSTABILITY.

SURFACE LOW DEEPENS TO 993 MB AS IT TRACKS NORTH OF LAKE SUPERIOR ON
FRIDAY.  THE OVERALL AMPLITUDE OF THIS SYSTEM CONTINUES TO FAVOR A
SLOWER DOWNSTREAM PROGRESSION OF THE MAIN HEIGHT FALL CENTER...WITH
THE CORRESPONDING COLD FRONTAL PASSAGE NOW EXPECTED EARLY FRIDAY
AFTERNOON.  A TRAILING PERIOD OF CVA AS THE STRONGER HEIGHT FALLS
COMMENCE AND COLD AIR ADVECTION ENSUES WILL SUSTAIN SCATTERED TO
NUMEROUS POST-FRONTAL SHOWER PRODUCTION LATE FRIDAY AND FRIDAY
NIGHT.

AMPLIFIED UPPER LEVEL TROUGH WILL BE SUSTAINED BY A 130 TO 140KT JET
THAT DIPS SOUTH OF THE GREAT LAKES INTO THE TENNESSEE VALLEY THROUGH
THE WEEKEND. THE UPPER LOW BECOMES CLOSED AT 500MB...BOTTOMING OUT
AROUND 538 DAM. EVEN AFTER SYNOPTIC RAIN ENDS ON SATURDAY...STEEP
LAPSE RATES IN PLACE WILL ALLOW FOR A 20 TO 30 PERCENT CHANCE FOR
RAIN SHOWERS EACH DAY IN THE EXTENDED PERIOD. STRONG GEOSTROPHIC
WIND COMPONENT WILL ALSO BE IN PLACE MOST OF THE PERIOD WITH DAYTIME
GUSTS OVER 20 MPH BEING COMMON.

&&

.MARINE...

SOUTHEAST WINDS WILL STEADILY INCREASE THURSDAY AND THURSDAY NIGHT
AS STRENGTHENING LOW PRESSURE TRACKS ACROSS LAKE SUPERIOR.  THIS
WILL RESULT IN A PERIOD OF GUSTY CONDITIONS FOR PORTIONS OF SOUTHERN
AND CENTRAL LAKE HURON BY LATE THURSDAY NIGHT AND EARLY FRIDAY.  THE
POTENTIAL EXISTS FOR SOME GUSTS OF UP TO 30 KNOTS...ALTHOUGH THE
ARRIVAL OF WARMER AIR WILL MAINTAIN A HIGHER DEGREE OF STABILITY
NEAR THE SURFACE.  THERE WILL BE A SLIGHT CHANCE FOR THUNDERSTORMS
AS WIDESPREAD SHOWERS MOVE THROUGH DURING THIS TIME.  A GUSTY
WESTERLY WIND FOR THE WEEKEND AS SEASONABLY COLD AIR OVERSPREADS THE
LAKES REGION.

&&

.AVIATION...ISSUED 147 PM EDT WED OCT 1 2014

//DISCUSSION...

RESIDUAL CYCLONIC FLOW IN ADDITION TO A RELATIVELY MOIST
SOUTHEASTERLY FLOW IS MAINTAINING A FAVORABLE ENVIRONMENT FOR
BOUNDARY LAYER CLOUD TODAY. LACK OF ADVECTION DURING THE NEXT 6
HOURS WILL MAKE CLEARING TRENDS VERY SLUGGISH. LATEST SATELLITE
IMAGERY SUPPORTS A CONVERSION OF CLOUD INTO CUMULOFORM AND CELL
BASED CONVECTIVE ELEMENTS. EXPECT DEEPENING CONVECTIVE CIRCULATIONS
TO LEAD TO A GREATER CLOUD SCALE SUBSIDENCE COMPONENT WHICH WILL
HELP NOCTURNAL COOLING PROCESSES THIS EVENING IN ALLOWING CLOUDS TO
DISSIPATE. PROVIDED THAT CLOUD COVER LESSENS TONIGHT...THE CONTINUED
LACK OF DRY AIR ADVECTION WILL THEN ALLOW THE POTENTIAL FOR FOG
DEVELOPMENT. CONFIDENCE IN COVERAGE AND TIMING IS LOW AT THIS
POINT...ALTHOUGH MODEL SOUNDINGS DO SUGGEST THAT DEVELOPMENT COULD
HAPPEN RATHER QUICK...SOMETIME SHORTLY AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FT PERSISTING THIS
AFTERNOON.

* LOW TO MEDIUM CONFIDENCE IN CEILINGS BELOW 200 FT AND/OR
VISIBILITIES BELOW A HALF MILE AFTER MIDNIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...CB
LONG TERM....MR/MM
MARINE.......MR
AVIATION.....CB


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







000
FXUS63 KDTX 011954
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
354 PM EDT WED OCT 1 2014

.SHORT TERM...TONIGHT

SOUTHEASTERN MICHIGAN WILL REMAIN UNDER THE SPELL OF THE STRONG
SURFACE ANTICYCLONE TONIGHT OVER PORTIONS OF EASTERN QUEBEC AND
CANADIAN MARITIMES WITH A SUBSTANTIAL SURFACE RIDGE EXTENDING BACK
INTO THE GREAT LAKES REGION. THIS FEATURE WILL CONTINUE TO DIRECT A
SOUTHEASTERLY LOW TROPOSPHERE FEED INTO THE STATE DESPITE A WEAK
MIDLEVEL RIDGE SLIDING OVERHEAD. THIS UPPER LEVEL RIDGE WILL
ESSENTIALLY CAUSE THE PATTERN LOCALLY TO REMAIN STAGNANT THROUGH THE
OVERNIGHT...DISALLOWING MUCH IN THE WAY OF ADVECTIONS OR AIRMASS
TURNOVER. CLOUD TRENDS THIS AFTERNOON HAVE BEEN SLUGGISH IN MANY
AREAS WITH A TRANSITION FROM STRATUS TO CUMULOFORM. THERE HAS BEEN A
RAPID CLEARING TREND OVER PORTIONS OF SOUTH CENTRAL LOWER MICHIGAN
BUT SUSPECT THIS TO SLOW DOWN AND NOT MAKE MUCH INROADS TO
SOUTHEASTERN MICHIGAN BEFORE SUNDOWN. INSTEAD...EXPECT VERTICAL
CLOUD CIRCULATIONS TO DEEPEN YET OVER THE NEXT 4 HOURS WHICH WILL
SUPPORT GREATER CONVECTIVE ELEMENT SPACING AND INTRODUCE GREATER
CLOUD SCALE SUBSIDENCE AND ENTRAINMENT OF DRY AIR ALOFT. THIS SHOULD
SET THE STAGES FOR A RAPID CLEARING TREND IN MANY AREAS POST SUNSET
WITH NOCTURNAL COOLING.

NAM AND LATEST HRRR NWP IS VERY SUPPORTIVE OF FOG TONIGHT WITH A
MUCH BETTER PROFILE FOR NEAR SURFACE SATURATION IN COMPARISON TO
YESTERDAY MORNING. GIVEN THE AFOREMENTIONED LACK OF ADVECTIONS ALONG
WITH THE CONTINUATION OF GREENUP ACROSS THE AREA...HIGH AMBIENT
MOISTURE IN THE BACKGROUND SHOULD SUPPORT FOG FAIRLY EARLY
TONIGHT...I.E. SHORTLY AFTER MIDNIGHT. EXPECTATIONS ARE FOR FOG TO
DEVELOP ACROSS PORTIONS OF ONTARIO...PORT HURON AND THE EASTERN
THUMB BEFORE SPREADING WESTWARD. MODELS ARE ALSO SHOWING A SIGNAL
THAT AREAS SOUTH AND EAST OF THE TERRAIN IN HIGHER SURFACE PRESSURE
AREAS COULD VERY WELL BE A FAVORABLE ZONE FOR FOG DEVELOPMENT. GIVEN
THERMODYNAMIC STRUCTURE...DENSE FOG WILL BE POSSIBLE. CONFIDENCE IS
NOT 100 PERCENT AS IT SELDOM IS...AND WILL GIVE LATER SHIFTS THE
FLEXIBILITY ON ANY POSSIBLE HEADLINE DECISIONS.

&&

.LONG TERM...

THE NORTHERN PORTION OF THE EXISTING LONGWAVE TROUGHING NOW
ENCOMPASSING MUCH OF THE WESTERN CONUS WILL UNDERGO SUBSTANTIAL
AMPLIFICATION OVER THE NEXT 48 HOURS.  THIS PROCESS WILL COMMENCE AS
STRONG SHORTWAVE ENERGY AND AN ATTENDANT 140 KT UPPER JET CORE
CURRENTLY OVER BRITISH COLUMBIA DIG INTO THE LOWER HEIGHT FIELD.
STRENGTHENING DYNAMICS ATTENDANT TO A LEAD WAVE UNDERCUTTING THE
AMPLIFYING TROUGH WILL BRING A PERIOD OF ACTIVE WEATHER TO END THE
WORK WEEK.  THE DEEPENING PROCESS WILL THEN LEAVE A CLOSED LOW
CONFIGURATION CENTERED JUST TO THE NORTH FOR THE UPCOMING
WEEKEND...SPELLING A CONSIDERABLY COLDER AND UNSETTLED PERIOD.

A DEEPER SOUTHWESTERLY FLOW TAKES HOLD ON THURSDAY AS THE
GRADUALLY EXPANDING HEIGHT FALLS NUDGE THE EXISTING UPPER RIDGE TO
THE EAST.  THIS PROCESS WILL MIX OUT ANY LINGERING FOG THROUGH LATE
MORNING...WITH THE ENSUING INCREASE IN MID LEVEL WARM AIR AND
THETA-E ADVECTION PROMPTING A STEADY THICKENING OF A HIGH BASED
CLOUD DECK DURING THE FIRST HALF OF THE DAY.  DESPITE THE WARMING
THERMAL PROFILE...A LINGERING SOUTHEAST SURFACE WIND AND LIMITED
MIXING DEPTH WILL MUTE THE OVERALL RESPONSE SLIGHTLY.  IN ACCORDANCE
WITH THE GOING FORECAST...WILL CONTINUE TO TEMPER EXPECTATIONS WITH
HIGHS OF LOW TO MID 70S.  TANGIBLE FORCING THROUGH THE DAYLIGHT
PERIOD REMAINS LESS DEFINED LOCALLY...THE AREA LARGELY REMOVED TO
THE EAST FROM THE MAIN CORRIDOR OF ASCENT LOCKED ONTO THE
THETA-E RIDGE AND PRIMARY TRAJECTORY OF ANY LOWER AMPLITUDE SHORTWAVE
ENERGY FUNNELING THROUGH THE MEAN SW FLOW.  THERE REMAINS THE
POTENTIAL FOR THIS AXIS TO CREEP FAR ENOUGH EAST TO SUPPORT SOME
LIGHT SHOWER DEVELOPMENT...PARTICULARLY ACROSS THE TRI-CITIES.  LOW
CHANCE POPS REMAIN APPROPRIATE FOR THIS AREA GIVEN THE HIGH DEGREE
OF UNCERTAINTY.

THE INCREASING INTERACTION BETWEEN THE AFOREMENTIONED SOUTHERN
WAVE EJECTING NORTHEAST OUT OF THE SOUTHERN PLAINS AND THE DEEPENING
LOW ACROSS THE DAKOTAS WILL PROMPT RAPID SURFACE CYCLOGENESIS AND A
STRENGTHENING OF THE ATTENDANT COLD FRONT UPSTREAM BY THURSDAY
NIGHT.  THE DOWNSTREAM PROPAGATION OF A STRENGTHENING WIND FIELD
/50 KTS AT 850MB/ EMBEDDED WITHIN THE WARM SECTOR AND AT THE EDGE OF
THE INBOUND LOWER HEIGHT FIELD WILL LIKELY PROMOTE AN EXPANSION IN
PRECIPITATION COVERAGE THROUGHOUT THE MIDWEST BY LATE THURSDAY.
THIS FORCING REMAINS FORECAST TO TRACK THROUGH SE MICHIGAN LATE
THURSDAY NIGHT AND EARLY FRIDAY...A CORRESPONDING STEADY INCREASE IN
PRECIPITATION CHANCES COMMENCING DURING THIS TIME.  DEEPEST ASCENT
IN PLACE DURING THE FIRST HALF OF FRIDAY...A PERIOD OF SOLID UPPER
DIVERGENCE AND CVA WORKING INTO A MOISTENING PRE-FRONTAL
ENVIRONMENT.  EXISTING MID LEVEL INSTABILITY CERTAINLY SUFFICIENT TO
SUPPORT A THUNDER MENTION...A FEW STRONGER GUSTS A POSSIBILITY GIVEN
THE WIND FIELD SHOULD BEST CORES CAPITALIZE ON THE LIMITED
INSTABILITY.

SURFACE LOW DEEPENS TO 993 MB AS IT TRACKS NORTH OF LAKE SUPERIOR ON
FRIDAY.  THE OVERALL AMPLITUDE OF THIS SYSTEM CONTINUES TO FAVOR A
SLOWER DOWNSTREAM PROGRESSION OF THE MAIN HEIGHT FALL CENTER...WITH
THE CORRESPONDING COLD FRONTAL PASSAGE NOW EXPECTED EARLY FRIDAY
AFTERNOON.  A TRAILING PERIOD OF CVA AS THE STRONGER HEIGHT FALLS
COMMENCE AND COLD AIR ADVECTION ENSUES WILL SUSTAIN SCATTERED TO
NUMEROUS POST-FRONTAL SHOWER PRODUCTION LATE FRIDAY AND FRIDAY
NIGHT.

AMPLIFIED UPPER LEVEL TROUGH WILL BE SUSTAINED BY A 130 TO 140KT JET
THAT DIPS SOUTH OF THE GREAT LAKES INTO THE TENNESSEE VALLEY THROUGH
THE WEEKEND. THE UPPER LOW BECOMES CLOSED AT 500MB...BOTTOMING OUT
AROUND 538 DAM. EVEN AFTER SYNOPTIC RAIN ENDS ON SATURDAY...STEEP
LAPSE RATES IN PLACE WILL ALLOW FOR A 20 TO 30 PERCENT CHANCE FOR
RAIN SHOWERS EACH DAY IN THE EXTENDED PERIOD. STRONG GEOSTROPHIC
WIND COMPONENT WILL ALSO BE IN PLACE MOST OF THE PERIOD WITH DAYTIME
GUSTS OVER 20 MPH BEING COMMON.

&&

.MARINE...

SOUTHEAST WINDS WILL STEADILY INCREASE THURSDAY AND THURSDAY NIGHT
AS STRENGTHENING LOW PRESSURE TRACKS ACROSS LAKE SUPERIOR.  THIS
WILL RESULT IN A PERIOD OF GUSTY CONDITIONS FOR PORTIONS OF SOUTHERN
AND CENTRAL LAKE HURON BY LATE THURSDAY NIGHT AND EARLY FRIDAY.  THE
POTENTIAL EXISTS FOR SOME GUSTS OF UP TO 30 KNOTS...ALTHOUGH THE
ARRIVAL OF WARMER AIR WILL MAINTAIN A HIGHER DEGREE OF STABILITY
NEAR THE SURFACE.  THERE WILL BE A SLIGHT CHANCE FOR THUNDERSTORMS
AS WIDESPREAD SHOWERS MOVE THROUGH DURING THIS TIME.  A GUSTY
WESTERLY WIND FOR THE WEEKEND AS SEASONABLY COLD AIR OVERSPREADS THE
LAKES REGION.

&&

.AVIATION...ISSUED 147 PM EDT WED OCT 1 2014

//DISCUSSION...

RESIDUAL CYCLONIC FLOW IN ADDITION TO A RELATIVELY MOIST
SOUTHEASTERLY FLOW IS MAINTAINING A FAVORABLE ENVIRONMENT FOR
BOUNDARY LAYER CLOUD TODAY. LACK OF ADVECTION DURING THE NEXT 6
HOURS WILL MAKE CLEARING TRENDS VERY SLUGGISH. LATEST SATELLITE
IMAGERY SUPPORTS A CONVERSION OF CLOUD INTO CUMULOFORM AND CELL
BASED CONVECTIVE ELEMENTS. EXPECT DEEPENING CONVECTIVE CIRCULATIONS
TO LEAD TO A GREATER CLOUD SCALE SUBSIDENCE COMPONENT WHICH WILL
HELP NOCTURNAL COOLING PROCESSES THIS EVENING IN ALLOWING CLOUDS TO
DISSIPATE. PROVIDED THAT CLOUD COVER LESSENS TONIGHT...THE CONTINUED
LACK OF DRY AIR ADVECTION WILL THEN ALLOW THE POTENTIAL FOR FOG
DEVELOPMENT. CONFIDENCE IN COVERAGE AND TIMING IS LOW AT THIS
POINT...ALTHOUGH MODEL SOUNDINGS DO SUGGEST THAT DEVELOPMENT COULD
HAPPEN RATHER QUICK...SOMETIME SHORTLY AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FT PERSISTING THIS
AFTERNOON.

* LOW TO MEDIUM CONFIDENCE IN CEILINGS BELOW 200 FT AND/OR
VISIBILITIES BELOW A HALF MILE AFTER MIDNIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...CB
LONG TERM....MR/MM
MARINE.......MR
AVIATION.....CB


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








000
FXUS63 KDTX 011747
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
147 PM EDT WED OCT 1 2014


.AVIATION...

//DISCUSSION...

RESIDUAL CYCLONIC FLOW IN ADDITION TO A RELATIVELY MOIST
SOUTHEASTERLY FLOW IS MAINTAINING A FAVORABLE ENVIRONMENT FOR
BOUNDARY LAYER CLOUD TODAY. LACK OF ADVECTION DURING THE NEXT 6
HOURS WILL MAKE CLEARING TRENDS VERY SLUGGISH. LATEST SATELLITE
IMAGERY SUPPORTS A CONVERSION OF CLOUD INTO CUMULOFORM AND CELL
BASED CONVECTIVE ELEMENTS. EXPECT DEEPENING CONVECTIVE CIRCULATIONS
TO LEAD TO A GREATER CLOUD SCALE SUBSIDENCE COMPONENT WHICH WILL
HELP NOCTURNAL COOLING PROCESSES THIS EVENING IN ALLOWING CLOUDS TO
DISSIPATE. PROVIDED THAT CLOUD COVER LESSENS TONIGHT...THE CONTINUED
LACK OF DRY AIR ADVECTION WILL THEN ALLOW THE POTENTIAL FOR FOG
DEVELOPMENT. CONFIDENCE IN COVERAGE AND TIMING IS LOW AT THIS
POINT...ALTHOUGH MODEL SOUNDINGS DO SUGGEST THAT DEVELOPMENT COULD
HAPPEN RATHER QUICK...SOMETIME SHORTLY AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FT PERSISTING THIS
AFTERNOON.

* LOW TO MEDIUM CONFIDENCE IN CEILINGS BELOW 200 FT AND/OR
VISIBILITIES BELOW A HALF MILE AFTER MIDNIGHT.

&&

.PREV DISCUSSION...ISSUED 322 AM EDT WED OCT 1 2014

SHORT TERM...TODAY AND TONIGHT

THE UPPER LOW WHICH IMPACTED SE MI YESTERDAY IS SHOWN ON THE LATEST
WATER VAPOR LOOP ROTATING INTO THE MID ATLANTIC...TUCKED UNDER THE
UPPER RIDGE NOW EXPANDING INTO SRN QUEBEC. A MID LEVEL SHEAR AXIS
EXTENDING FROM THE DEPARTING UPPER LOW WILL LINGER OVER SE MI INTO
LATE AFTERNOON BEFORE BEING WASHED OUT BY SHORT WAVE RIDGING. THE
NET RESULT OF THE BUILDING MID LEVEL HEIGHTS OVER LOWER MI WILL BE
TO SUSTAIN LARGE SCALE SUBSIDENCE THROUGH MUCH OF THE SHORT TERM.
THE LATEST SFC ANALYSIS SHOWS A TROUGH AXIS EXTENDING ACROSS THE
THUMB AND SAGINAW VALLEY. ENHANCED CONVERGENCE ALONG THIS BOUNDARY
IS ALLOWING SOME DRIZZLE TO PERSIST. EXPANDING SFC HIGH PRESSURE
FROM THE NORTH WILL CONTINUE TO FORCE THIS BOUNDARY SOUTH THIS
MORNING...WITH IT EXPECTED TO WASH OUT COMPLETELY BY AFTERNOON AS
THE SFC HIGH PRESSURE TAKES HOLD.

THE CLOUD AND FOG FORECAST WILL REMAIN THE MORE CHALLENGING ASPECT
OF THE SHORT TERM. ASIDE FROM LENAWEE AND MONROE COUNTIES WHICH
EXPERIENCED A PERIOD OF CLEAR SKIES...CLOUDS REMAINED SOLID
ACROSS THE FORECAST AREA OVERNIGHT. E-NE LOW LEVEL WINDS DURING
THE NIGHT ADVECTED VERY MOIST AIR IN FROM SRN ONTARIO /WHERE SFC
DEWPOINTS WERE IN THE UPPER 50S YESTERDAY AFTERNOON/. THE RESULT
HAS BEEN A 200-400 FT STRATUS DECK BLANKETING MOST OF THE NRN TWO
THIRDS OF THE FORECAST AREA. WEAKENING LOW LEVEL FLOW AND A
MOISTURE RICH BOUNDARY LAYER MAY CONTINUE TO LOWER THE CLOUD BASES
TOWARD DAYBREAK...WHICH WILL SUSTAIN SOME FOG /ESPECIALLY IN THE
HIGHER TERRAIN OF THE IRISH HILLS/. MODEL SOLUTIONS SUGGEST
DAYTIME HEATING AND LOW LEVEL ANTICYCLONIC FLOW WILL LEAD TO
CLEARING THIS AFTERNOON. HOWEVER... THE 00Z DTX SOUNDING SHOWED A
SECONDARY INVERSION /RATHER DEEP/ BASED NEAR 800MB WHICH NONE OF
THE MODEL SOLUTIONS RESOLVED. WITH SOME THERMAL TROUGHING NEAR
850MB FORECAST TO LINGER THROUGH THE AFTERNOON...DAYTIME HEATING
WILL MOST LIKELY LEAD TO AN EXTENSIVE HIGHER BASED STRATO CU
FIELD. THIS WILL SUPPORT LEANING ON THE LOWER END OF GUIDANCE MAX
TEMPS /LOW-MID 60S/.

WARMING IN THE 900-800MB LAYER THIS EVENING INTO THE OVERNIGHT
SHOULD ERODE ANY LINGERING INVERSION...OFFERING THE POSSIBILITY FOR
SOME CLEARING PRIOR TO THE ARRIVAL OF THE HIGH CLOUDS FROM THE NEXT
SYSTEM. THE LOW LEVELS ACROSS THE ERN GREAT LAKES WILL REMAIN RATHER
MOIST TODAY. A SE COMPONENT TO THE SFC WINDS TONIGHT AND INFLUENCE
FROM LAKE ERIE WILL THUS PROVIDE A CHANCE FOR SOME FOG AND/OR
STRATUS REDEVELOPMENT TOWARD DAYBREAK THURS.

LONG TERM...

ILL-DEFINED WARM FRONT LIFTING INTO NORTHERN LOWER MICHIGAN DURING
THURSDAY...WITH SOLID WARM ADVECTION TAKING PLACE OVER SOUTHEAST
MICHIGAN...AS 925 MB TEMPS WARM INTO THE UPPER TEENS TO AROUND 20 C
TOWARD 00Z FRIDAY. STILL...WITH SURFACE FLOW BACKED OUT OF THE
SOUTHEAST AND INCREASING/THICKENING CLOUDS WITH MOISTURE
ADVECTION/ISENTROPIC ASCENT...BOUNDARY LAYER MIXING WILL PROBABLY
COME UP JUST SHORT OF 925 MB...AND WILL CONTINUE WITH THE MORE
SUBDUED MAX TEMP FORECAST IN THE LOW TO MID 70S...WITH LIMITED RAIN
CHANCES...MAINLY ALONG/WEST OF U.S. 23 THROUGH THE DAY.

AN EVEN DEEPER MOISTURE SURGE THURSDAY NIGHT WITH BURGEONING HEIGHT
FALLS WILL ALLOW FOR DEVELOPING RAIN SHOWERS. THE TREND OF A SLOWER
AND STRONGER STORM SYSTEM FOR THE END OF THE WORK WEEK HAS CONTINUED
WITH THE 00Z MODELS...AS MERGING HEIGHT FALL CENTERS CONSOLIDATE
OVER THE CENTRAL CONUS ON THURSDAY...WITH POTENT UPPER WAVE/PV
ANOMALY OVER NORTHERN BRITISH COLUMBIA FORECASTED TO TRACK ALONG OR
SOUTH OF THE SOUTHERN MICHIGAN BORDER FRIDAY NIGHT PER
GFS/EURO...WHICH WILL SERVE AS THE ANCHOR/CENTER POINT OF THE
EASTERN NORTH AMERICAN LONGWAVE TROUGH DURING THE FIRST HALF OF THE
WEEKEND.

WITH SLOWER PASSAGE OF THE COLD FRONT ON FRIDAY...MAXES HAVE A
REASONABLE SHOT OF CLIMBING PAST 70 DEGREES BEFORE WE TAKE BIG NOSE
DIVE FOR THE WEEKEND...AS 850 MB TEMPS FALL BELOW ZERO...POTENTIALLY
AS COLD AS -4 C (SEE 00Z GFS). EVEN THOUGH INSTABILITY LOOKS MODEST
THURSDAY NIGHT-FRIDAY...SLIGHTLY NEGATIVE SFC-850 MB LI`S...ABOUT
500 J/KG OF CAPE DURING FRIDAY IS A BIT CONCERNING WITH 50 KNOTS
NOTED AT 850 MB...AND STRONG GUSTY WINDS APPEARS LIKELY WITH ANY
CONVECTIVE ACTIVITY.

CYCLONIC FLOW...STEEP LOW LEVEL LAPSE RATES...LAKE MICHIGAN
CONTRIBUTION ON SATURDAY SHOULD ASSURE SCATTERED TO NUMEROUS RAIN
SHOWERS...AS THERE ALSO LOOKS TO BE A PRONOUNCED SURFACE TROUGH
ROTATING THROUGH. COLD WESTERLY FLOW OFF LAKE MICHIGAN ON SUNDAY
STILL PROBABLY SUFFICIENT TO GENERATE SCATTERED LIGHT SHOWERS...WITH
MAXES HOLDING IN THE LOW TO MID 50S .

MARINE...

HIGH PRESSURE SITUATED OVER THE CENTRAL GREAT LAKES WILL PROVIDE
LIGHT WINDS AND LOW WAVES INTO THURSDAY MORNING. SOUTHERLY WINDS
WILL BEGIN TO PICK UP THURSDAY AFTERNOON...AS A STRONG COLD FRONT
APPROACHES. SOUTH WINDS UP TO 30 KNOTS OVER THE OPEN WATERS OF LAKE
HURON ARE ANTICIPATED FRIDAY MORNING...AS THE COLD FRONT MOVES
THROUGH DURING THE AFTERNOON HOURS. WARM AIR STREAMING INTO THE
REGION IS EXPECTED TO LEAD TO STABLE NEAR SURFACE PROFILES...AND
THUS KEEP WIND SPEEDS PREDOMINATELY BELOW 30 KNOTS. ANY CONVECTIVE
ACTIVITY WITH THE COLD FRONT COULD LEAD TO STRONGER WIND SPEEDS
HOWEVER. SEASONABLY COLD AIRMASS FOLLOWING THE COLD FRONT FRIDAY
NIGHT INTO THE WEEKEND WILL BE CONDUCIVE TO HIGHER WAVES ALONG WITH
NUMEROUS RAIN SHOWERS...AS WESTERLY WINDS GUST UP TO 30 KNOTS OVER
THE OPEN WATERS OF LAKE HURON.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....CB
SHORT TERM...SC
LONG TERM....SF
MARINE.......SF


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







000
FXUS63 KDTX 011747
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
147 PM EDT WED OCT 1 2014


.AVIATION...

//DISCUSSION...

RESIDUAL CYCLONIC FLOW IN ADDITION TO A RELATIVELY MOIST
SOUTHEASTERLY FLOW IS MAINTAINING A FAVORABLE ENVIRONMENT FOR
BOUNDARY LAYER CLOUD TODAY. LACK OF ADVECTION DURING THE NEXT 6
HOURS WILL MAKE CLEARING TRENDS VERY SLUGGISH. LATEST SATELLITE
IMAGERY SUPPORTS A CONVERSION OF CLOUD INTO CUMULOFORM AND CELL
BASED CONVECTIVE ELEMENTS. EXPECT DEEPENING CONVECTIVE CIRCULATIONS
TO LEAD TO A GREATER CLOUD SCALE SUBSIDENCE COMPONENT WHICH WILL
HELP NOCTURNAL COOLING PROCESSES THIS EVENING IN ALLOWING CLOUDS TO
DISSIPATE. PROVIDED THAT CLOUD COVER LESSENS TONIGHT...THE CONTINUED
LACK OF DRY AIR ADVECTION WILL THEN ALLOW THE POTENTIAL FOR FOG
DEVELOPMENT. CONFIDENCE IN COVERAGE AND TIMING IS LOW AT THIS
POINT...ALTHOUGH MODEL SOUNDINGS DO SUGGEST THAT DEVELOPMENT COULD
HAPPEN RATHER QUICK...SOMETIME SHORTLY AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FT PERSISTING THIS
AFTERNOON.

* LOW TO MEDIUM CONFIDENCE IN CEILINGS BELOW 200 FT AND/OR
VISIBILITIES BELOW A HALF MILE AFTER MIDNIGHT.

&&

.PREV DISCUSSION...ISSUED 322 AM EDT WED OCT 1 2014

SHORT TERM...TODAY AND TONIGHT

THE UPPER LOW WHICH IMPACTED SE MI YESTERDAY IS SHOWN ON THE LATEST
WATER VAPOR LOOP ROTATING INTO THE MID ATLANTIC...TUCKED UNDER THE
UPPER RIDGE NOW EXPANDING INTO SRN QUEBEC. A MID LEVEL SHEAR AXIS
EXTENDING FROM THE DEPARTING UPPER LOW WILL LINGER OVER SE MI INTO
LATE AFTERNOON BEFORE BEING WASHED OUT BY SHORT WAVE RIDGING. THE
NET RESULT OF THE BUILDING MID LEVEL HEIGHTS OVER LOWER MI WILL BE
TO SUSTAIN LARGE SCALE SUBSIDENCE THROUGH MUCH OF THE SHORT TERM.
THE LATEST SFC ANALYSIS SHOWS A TROUGH AXIS EXTENDING ACROSS THE
THUMB AND SAGINAW VALLEY. ENHANCED CONVERGENCE ALONG THIS BOUNDARY
IS ALLOWING SOME DRIZZLE TO PERSIST. EXPANDING SFC HIGH PRESSURE
FROM THE NORTH WILL CONTINUE TO FORCE THIS BOUNDARY SOUTH THIS
MORNING...WITH IT EXPECTED TO WASH OUT COMPLETELY BY AFTERNOON AS
THE SFC HIGH PRESSURE TAKES HOLD.

THE CLOUD AND FOG FORECAST WILL REMAIN THE MORE CHALLENGING ASPECT
OF THE SHORT TERM. ASIDE FROM LENAWEE AND MONROE COUNTIES WHICH
EXPERIENCED A PERIOD OF CLEAR SKIES...CLOUDS REMAINED SOLID
ACROSS THE FORECAST AREA OVERNIGHT. E-NE LOW LEVEL WINDS DURING
THE NIGHT ADVECTED VERY MOIST AIR IN FROM SRN ONTARIO /WHERE SFC
DEWPOINTS WERE IN THE UPPER 50S YESTERDAY AFTERNOON/. THE RESULT
HAS BEEN A 200-400 FT STRATUS DECK BLANKETING MOST OF THE NRN TWO
THIRDS OF THE FORECAST AREA. WEAKENING LOW LEVEL FLOW AND A
MOISTURE RICH BOUNDARY LAYER MAY CONTINUE TO LOWER THE CLOUD BASES
TOWARD DAYBREAK...WHICH WILL SUSTAIN SOME FOG /ESPECIALLY IN THE
HIGHER TERRAIN OF THE IRISH HILLS/. MODEL SOLUTIONS SUGGEST
DAYTIME HEATING AND LOW LEVEL ANTICYCLONIC FLOW WILL LEAD TO
CLEARING THIS AFTERNOON. HOWEVER... THE 00Z DTX SOUNDING SHOWED A
SECONDARY INVERSION /RATHER DEEP/ BASED NEAR 800MB WHICH NONE OF
THE MODEL SOLUTIONS RESOLVED. WITH SOME THERMAL TROUGHING NEAR
850MB FORECAST TO LINGER THROUGH THE AFTERNOON...DAYTIME HEATING
WILL MOST LIKELY LEAD TO AN EXTENSIVE HIGHER BASED STRATO CU
FIELD. THIS WILL SUPPORT LEANING ON THE LOWER END OF GUIDANCE MAX
TEMPS /LOW-MID 60S/.

WARMING IN THE 900-800MB LAYER THIS EVENING INTO THE OVERNIGHT
SHOULD ERODE ANY LINGERING INVERSION...OFFERING THE POSSIBILITY FOR
SOME CLEARING PRIOR TO THE ARRIVAL OF THE HIGH CLOUDS FROM THE NEXT
SYSTEM. THE LOW LEVELS ACROSS THE ERN GREAT LAKES WILL REMAIN RATHER
MOIST TODAY. A SE COMPONENT TO THE SFC WINDS TONIGHT AND INFLUENCE
FROM LAKE ERIE WILL THUS PROVIDE A CHANCE FOR SOME FOG AND/OR
STRATUS REDEVELOPMENT TOWARD DAYBREAK THURS.

LONG TERM...

ILL-DEFINED WARM FRONT LIFTING INTO NORTHERN LOWER MICHIGAN DURING
THURSDAY...WITH SOLID WARM ADVECTION TAKING PLACE OVER SOUTHEAST
MICHIGAN...AS 925 MB TEMPS WARM INTO THE UPPER TEENS TO AROUND 20 C
TOWARD 00Z FRIDAY. STILL...WITH SURFACE FLOW BACKED OUT OF THE
SOUTHEAST AND INCREASING/THICKENING CLOUDS WITH MOISTURE
ADVECTION/ISENTROPIC ASCENT...BOUNDARY LAYER MIXING WILL PROBABLY
COME UP JUST SHORT OF 925 MB...AND WILL CONTINUE WITH THE MORE
SUBDUED MAX TEMP FORECAST IN THE LOW TO MID 70S...WITH LIMITED RAIN
CHANCES...MAINLY ALONG/WEST OF U.S. 23 THROUGH THE DAY.

AN EVEN DEEPER MOISTURE SURGE THURSDAY NIGHT WITH BURGEONING HEIGHT
FALLS WILL ALLOW FOR DEVELOPING RAIN SHOWERS. THE TREND OF A SLOWER
AND STRONGER STORM SYSTEM FOR THE END OF THE WORK WEEK HAS CONTINUED
WITH THE 00Z MODELS...AS MERGING HEIGHT FALL CENTERS CONSOLIDATE
OVER THE CENTRAL CONUS ON THURSDAY...WITH POTENT UPPER WAVE/PV
ANOMALY OVER NORTHERN BRITISH COLUMBIA FORECASTED TO TRACK ALONG OR
SOUTH OF THE SOUTHERN MICHIGAN BORDER FRIDAY NIGHT PER
GFS/EURO...WHICH WILL SERVE AS THE ANCHOR/CENTER POINT OF THE
EASTERN NORTH AMERICAN LONGWAVE TROUGH DURING THE FIRST HALF OF THE
WEEKEND.

WITH SLOWER PASSAGE OF THE COLD FRONT ON FRIDAY...MAXES HAVE A
REASONABLE SHOT OF CLIMBING PAST 70 DEGREES BEFORE WE TAKE BIG NOSE
DIVE FOR THE WEEKEND...AS 850 MB TEMPS FALL BELOW ZERO...POTENTIALLY
AS COLD AS -4 C (SEE 00Z GFS). EVEN THOUGH INSTABILITY LOOKS MODEST
THURSDAY NIGHT-FRIDAY...SLIGHTLY NEGATIVE SFC-850 MB LI`S...ABOUT
500 J/KG OF CAPE DURING FRIDAY IS A BIT CONCERNING WITH 50 KNOTS
NOTED AT 850 MB...AND STRONG GUSTY WINDS APPEARS LIKELY WITH ANY
CONVECTIVE ACTIVITY.

CYCLONIC FLOW...STEEP LOW LEVEL LAPSE RATES...LAKE MICHIGAN
CONTRIBUTION ON SATURDAY SHOULD ASSURE SCATTERED TO NUMEROUS RAIN
SHOWERS...AS THERE ALSO LOOKS TO BE A PRONOUNCED SURFACE TROUGH
ROTATING THROUGH. COLD WESTERLY FLOW OFF LAKE MICHIGAN ON SUNDAY
STILL PROBABLY SUFFICIENT TO GENERATE SCATTERED LIGHT SHOWERS...WITH
MAXES HOLDING IN THE LOW TO MID 50S .

MARINE...

HIGH PRESSURE SITUATED OVER THE CENTRAL GREAT LAKES WILL PROVIDE
LIGHT WINDS AND LOW WAVES INTO THURSDAY MORNING. SOUTHERLY WINDS
WILL BEGIN TO PICK UP THURSDAY AFTERNOON...AS A STRONG COLD FRONT
APPROACHES. SOUTH WINDS UP TO 30 KNOTS OVER THE OPEN WATERS OF LAKE
HURON ARE ANTICIPATED FRIDAY MORNING...AS THE COLD FRONT MOVES
THROUGH DURING THE AFTERNOON HOURS. WARM AIR STREAMING INTO THE
REGION IS EXPECTED TO LEAD TO STABLE NEAR SURFACE PROFILES...AND
THUS KEEP WIND SPEEDS PREDOMINATELY BELOW 30 KNOTS. ANY CONVECTIVE
ACTIVITY WITH THE COLD FRONT COULD LEAD TO STRONGER WIND SPEEDS
HOWEVER. SEASONABLY COLD AIRMASS FOLLOWING THE COLD FRONT FRIDAY
NIGHT INTO THE WEEKEND WILL BE CONDUCIVE TO HIGHER WAVES ALONG WITH
NUMEROUS RAIN SHOWERS...AS WESTERLY WINDS GUST UP TO 30 KNOTS OVER
THE OPEN WATERS OF LAKE HURON.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....CB
SHORT TERM...SC
LONG TERM....SF
MARINE.......SF


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








000
FXUS63 KDTX 011057
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
657 AM EDT WED OCT 1 2014


.AVIATION...

//DISCUSSION...

A TWO TO THREE HUNDRED FOOT CEILING WITH AREAS OF DENSE FOG HAS BEEN
IMPACTING PTK/FNT/MBS THROUGH THE EARLY MORNING AND THERE ARE NO
INDICATIONS THAT THIS WILL CHANGE OVER THE NEXT 2 TO 3 HOURS.
DAYTIME HEATING WILL EVENTUALLY LIFT THE BASES. THE RATE AT WHICH
CEILINGS LIFT AND EXTENT OF LATE DAY CLEARING CARRIES A GOOD DEAL OF
UNCERTAINTY. GIVEN THE DEGREE OF LOW LEVEL MOISTURE AND TIME OF
YEAR...A GRADUAL LIFTING OF CEILING BASES WILL BE FORECAST IN THE
TAFS.

FOR DTW...THERE HAS BEEN A PERSISTENT AREA OF CLEARING ATTEMPTING TO
NUDGE INTO METRO DETROIT WHICH GREATLY COMPLICATES THE MORNING
CEILING/VSBY FORECAST. THE EXPECTATION IS THAT ANY CLEARING THIS
MORNING WILL BE BRIEF WITH THE ONSET OF DAYTIME HEATING LEADING TO A
FAST REDEVELOPMENT OF LOW CLOUDS.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE IN CEILINGS BELOW 5000 FT THIS MORNING AND
AFTERNOON.

* LOW CONFIDENCE IN CEILINGS BELOW 200 FT AND/OR VISIBILITIES BELOW
A HALF MILE THURSDAY MORNING.

&&

.PREV DISCUSSION...ISSUED 322 AM EDT WED OCT 1 2014

SHORT TERM...TODAY AND TONIGHT

THE UPPER LOW WHICH IMPACTED SE MI YESTERDAY IS SHOWN ON THE LATEST
WATER VAPOR LOOP ROTATING INTO THE MID ATLANTIC...TUCKED UNDER THE
UPPER RIDGE NOW EXPANDING INTO SRN QUEBEC. A MID LEVEL SHEAR AXIS
EXTENDING FROM THE DEPARTING UPPER LOW WILL LINGER OVER SE MI INTO
LATE AFTERNOON BEFORE BEING WASHED OUT BY SHORT WAVE RIDGING. THE
NET RESULT OF THE BUILDING MID LEVEL HEIGHTS OVER LOWER MI WILL BE
TO SUSTAIN LARGE SCALE SUBSIDENCE THROUGH MUCH OF THE SHORT TERM.
THE LATEST SFC ANALYSIS SHOWS A TROUGH AXIS EXTENDING ACROSS THE
THUMB AND SAGINAW VALLEY. ENHANCED CONVERGENCE ALONG THIS BOUNDARY
IS ALLOWING SOME DRIZZLE TO PERSIST. EXPANDING SFC HIGH PRESSURE
FROM THE NORTH WILL CONTINUE TO FORCE THIS BOUNDARY SOUTH THIS
MORNING...WITH IT EXPECTED TO WASH OUT COMPLETELY BY AFTERNOON AS
THE SFC HIGH PRESSURE TAKES HOLD.

THE CLOUD AND FOG FORECAST WILL REMAIN THE MORE CHALLENGING ASPECT
OF THE SHORT TERM. ASIDE FROM LENAWEE AND MONROE COUNTIES WHICH
EXPERIENCED A PERIOD OF CLEAR SKIES...CLOUDS REMAINED SOLID
ACROSS THE FORECAST AREA OVERNIGHT. E-NE LOW LEVEL WINDS DURING
THE NIGHT ADVECTED VERY MOIST AIR IN FROM SRN ONTARIO /WHERE SFC
DEWPOINTS WERE IN THE UPPER 50S YESTERDAY AFTERNOON/. THE RESULT
HAS BEEN A 200-400 FT STRATUS DECK BLANKETING MOST OF THE NRN TWO
THIRDS OF THE FORECAST AREA. WEAKENING LOW LEVEL FLOW AND A
MOISTURE RICH BOUNDARY LAYER MAY CONTINUE TO LOWER THE CLOUD BASES
TOWARD DAYBREAK...WHICH WILL SUSTAIN SOME FOG /ESPECIALLY IN THE
HIGHER TERRAIN OF THE IRISH HILLS/. MODEL SOLUTIONS SUGGEST
DAYTIME HEATING AND LOW LEVEL ANTICYCLONIC FLOW WILL LEAD TO
CLEARING THIS AFTERNOON. HOWEVER... THE 00Z DTX SOUNDING SHOWED A
SECONDARY INVERSION /RATHER DEEP/ BASED NEAR 800MB WHICH NONE OF
THE MODEL SOLUTIONS RESOLVED. WITH SOME THERMAL TROUGHING NEAR
850MB FORECAST TO LINGER THROUGH THE AFTERNOON...DAYTIME HEATING
WILL MOST LIKELY LEAD TO AN EXTENSIVE HIGHER BASED STRATO CU
FIELD. THIS WILL SUPPORT LEANING ON THE LOWER END OF GUIDANCE MAX
TEMPS /LOW-MID 60S/.

WARMING IN THE 900-800MB LAYER THIS EVENING INTO THE OVERNIGHT
SHOULD ERODE ANY LINGERING INVERSION...OFFERING THE POSSIBILITY FOR
SOME CLEARING PRIOR TO THE ARRIVAL OF THE HIGH CLOUDS FROM THE NEXT
SYSTEM. THE LOW LEVELS ACROSS THE ERN GREAT LAKES WILL REMAIN RATHER
MOIST TODAY. A SE COMPONENT TO THE SFC WINDS TONIGHT AND INFLUENCE
FROM LAKE ERIE WILL THUS PROVIDE A CHANCE FOR SOME FOG AND/OR
STRATUS REDEVELOPMENT TOWARD DAYBREAK THURS.

LONG TERM...

ILL-DEFINED WARM FRONT LIFTING INTO NORTHERN LOWER MICHIGAN DURING
THURSDAY...WITH SOLID WARM ADVECTION TAKING PLACE OVER SOUTHEAST
MICHIGAN...AS 925 MB TEMPS WARM INTO THE UPPER TEENS TO AROUND 20 C
TOWARD 00Z FRIDAY. STILL...WITH SURFACE FLOW BACKED OUT OF THE
SOUTHEAST AND INCREASING/THICKENING CLOUDS WITH MOISTURE
ADVECTION/ISENTROPIC ASCENT...BOUNDARY LAYER MIXING WILL PROBABLY
COME UP JUST SHORT OF 925 MB...AND WILL CONTINUE WITH THE MORE
SUBDUED MAX TEMP FORECAST IN THE LOW TO MID 70S...WITH LIMITED RAIN
CHANCES...MAINLY ALONG/WEST OF U.S. 23 THROUGH THE DAY.

AN EVEN DEEPER MOISTURE SURGE THURSDAY NIGHT WITH BURGEONING HEIGHT
FALLS WILL ALLOW FOR DEVELOPING RAIN SHOWERS. THE TREND OF A SLOWER
AND STRONGER STORM SYSTEM FOR THE END OF THE WORK WEEK HAS CONTINUED
WITH THE 00Z MODELS...AS MERGING HEIGHT FALL CENTERS CONSOLIDATE
OVER THE CENTRAL CONUS ON THURSDAY...WITH POTENT UPPER WAVE/PV
ANOMALY OVER NORTHERN BRITISH COLUMBIA FORECASTED TO TRACK ALONG OR
SOUTH OF THE SOUTHERN MICHIGAN BORDER FRIDAY NIGHT PER
GFS/EURO...WHICH WILL SERVE AS THE ANCHOR/CENTER POINT OF THE
EASTERN NORTH AMERICAN LONGWAVE TROUGH DURING THE FIRST HALF OF THE
WEEKEND.

WITH SLOWER PASSAGE OF THE COLD FRONT ON FRIDAY...MAXES HAVE A
REASONABLE SHOT OF CLIMBING PAST 70 DEGREES BEFORE WE TAKE BIG NOSE
DIVE FOR THE WEEKEND...AS 850 MB TEMPS FALL BELOW ZERO...POTENTIALLY
AS COLD AS -4 C (SEE 00Z GFS). EVEN THOUGH INSTABILITY LOOKS MODEST
THURSDAY NIGHT-FRIDAY...SLIGHTLY NEGATIVE SFC-850 MB LI`S...ABOUT
500 J/KG OF CAPE DURING FRIDAY IS A BIT CONCERNING WITH 50 KNOTS
NOTED AT 850 MB...AND STRONG GUSTY WINDS APPEARS LIKELY WITH ANY
CONVECTIVE ACTIVITY.

CYCLONIC FLOW...STEEP LOW LEVEL LAPSE RATES...LAKE MICHIGAN
CONTRIBUTION ON SATURDAY SHOULD ASSURE SCATTERED TO NUMEROUS RAIN
SHOWERS...AS THERE ALSO LOOKS TO BE A PRONOUNCED SURFACE TROUGH
ROTATING THROUGH. COLD WESTERLY FLOW OFF LAKE MICHIGAN ON SUNDAY
STILL PROBABLY SUFFICIENT TO GENERATE SCATTERED LIGHT SHOWERS...WITH
MAXES HOLDING IN THE LOW TO MID 50S .

MARINE...

HIGH PRESSURE SITUATED OVER THE CENTRAL GREAT LAKES WILL PROVIDE
LIGHT WINDS AND LOW WAVES INTO THURSDAY MORNING. SOUTHERLY WINDS
WILL BEGIN TO PICK UP THURSDAY AFTERNOON...AS A STRONG COLD FRONT
APPROACHES. SOUTH WINDS UP TO 30 KNOTS OVER THE OPEN WATERS OF LAKE
HURON ARE ANTICIPATED FRIDAY MORNING...AS THE COLD FRONT MOVES
THROUGH DURING THE AFTERNOON HOURS. WARM AIR STREAMING INTO THE
REGION IS EXPECTED TO LEAD TO STABLE NEAR SURFACE PROFILES...AND
THUS KEEP WIND SPEEDS PREDOMINATELY BELOW 30 KNOTS. ANY CONVECTIVE
ACTIVITY WITH THE COLD FRONT COULD LEAD TO STRONGER WIND SPEEDS
HOWEVER. SEASONABLY COLD AIRMASS FOLLOWING THE COLD FRONT FRIDAY
NIGHT INTO THE WEEKEND WILL BE CONDUCIVE TO HIGHER WAVES ALONG WITH
NUMEROUS RAIN SHOWERS...AS WESTERLY WINDS GUST UP TO 30 KNOTS OVER
THE OPEN WATERS OF LAKE HURON.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....SC
SHORT TERM...SC
LONG TERM....SF
MARINE.......SF


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







000
FXUS63 KDTX 011057
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
657 AM EDT WED OCT 1 2014


.AVIATION...

//DISCUSSION...

A TWO TO THREE HUNDRED FOOT CEILING WITH AREAS OF DENSE FOG HAS BEEN
IMPACTING PTK/FNT/MBS THROUGH THE EARLY MORNING AND THERE ARE NO
INDICATIONS THAT THIS WILL CHANGE OVER THE NEXT 2 TO 3 HOURS.
DAYTIME HEATING WILL EVENTUALLY LIFT THE BASES. THE RATE AT WHICH
CEILINGS LIFT AND EXTENT OF LATE DAY CLEARING CARRIES A GOOD DEAL OF
UNCERTAINTY. GIVEN THE DEGREE OF LOW LEVEL MOISTURE AND TIME OF
YEAR...A GRADUAL LIFTING OF CEILING BASES WILL BE FORECAST IN THE
TAFS.

FOR DTW...THERE HAS BEEN A PERSISTENT AREA OF CLEARING ATTEMPTING TO
NUDGE INTO METRO DETROIT WHICH GREATLY COMPLICATES THE MORNING
CEILING/VSBY FORECAST. THE EXPECTATION IS THAT ANY CLEARING THIS
MORNING WILL BE BRIEF WITH THE ONSET OF DAYTIME HEATING LEADING TO A
FAST REDEVELOPMENT OF LOW CLOUDS.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE IN CEILINGS BELOW 5000 FT THIS MORNING AND
AFTERNOON.

* LOW CONFIDENCE IN CEILINGS BELOW 200 FT AND/OR VISIBILITIES BELOW
A HALF MILE THURSDAY MORNING.

&&

.PREV DISCUSSION...ISSUED 322 AM EDT WED OCT 1 2014

SHORT TERM...TODAY AND TONIGHT

THE UPPER LOW WHICH IMPACTED SE MI YESTERDAY IS SHOWN ON THE LATEST
WATER VAPOR LOOP ROTATING INTO THE MID ATLANTIC...TUCKED UNDER THE
UPPER RIDGE NOW EXPANDING INTO SRN QUEBEC. A MID LEVEL SHEAR AXIS
EXTENDING FROM THE DEPARTING UPPER LOW WILL LINGER OVER SE MI INTO
LATE AFTERNOON BEFORE BEING WASHED OUT BY SHORT WAVE RIDGING. THE
NET RESULT OF THE BUILDING MID LEVEL HEIGHTS OVER LOWER MI WILL BE
TO SUSTAIN LARGE SCALE SUBSIDENCE THROUGH MUCH OF THE SHORT TERM.
THE LATEST SFC ANALYSIS SHOWS A TROUGH AXIS EXTENDING ACROSS THE
THUMB AND SAGINAW VALLEY. ENHANCED CONVERGENCE ALONG THIS BOUNDARY
IS ALLOWING SOME DRIZZLE TO PERSIST. EXPANDING SFC HIGH PRESSURE
FROM THE NORTH WILL CONTINUE TO FORCE THIS BOUNDARY SOUTH THIS
MORNING...WITH IT EXPECTED TO WASH OUT COMPLETELY BY AFTERNOON AS
THE SFC HIGH PRESSURE TAKES HOLD.

THE CLOUD AND FOG FORECAST WILL REMAIN THE MORE CHALLENGING ASPECT
OF THE SHORT TERM. ASIDE FROM LENAWEE AND MONROE COUNTIES WHICH
EXPERIENCED A PERIOD OF CLEAR SKIES...CLOUDS REMAINED SOLID
ACROSS THE FORECAST AREA OVERNIGHT. E-NE LOW LEVEL WINDS DURING
THE NIGHT ADVECTED VERY MOIST AIR IN FROM SRN ONTARIO /WHERE SFC
DEWPOINTS WERE IN THE UPPER 50S YESTERDAY AFTERNOON/. THE RESULT
HAS BEEN A 200-400 FT STRATUS DECK BLANKETING MOST OF THE NRN TWO
THIRDS OF THE FORECAST AREA. WEAKENING LOW LEVEL FLOW AND A
MOISTURE RICH BOUNDARY LAYER MAY CONTINUE TO LOWER THE CLOUD BASES
TOWARD DAYBREAK...WHICH WILL SUSTAIN SOME FOG /ESPECIALLY IN THE
HIGHER TERRAIN OF THE IRISH HILLS/. MODEL SOLUTIONS SUGGEST
DAYTIME HEATING AND LOW LEVEL ANTICYCLONIC FLOW WILL LEAD TO
CLEARING THIS AFTERNOON. HOWEVER... THE 00Z DTX SOUNDING SHOWED A
SECONDARY INVERSION /RATHER DEEP/ BASED NEAR 800MB WHICH NONE OF
THE MODEL SOLUTIONS RESOLVED. WITH SOME THERMAL TROUGHING NEAR
850MB FORECAST TO LINGER THROUGH THE AFTERNOON...DAYTIME HEATING
WILL MOST LIKELY LEAD TO AN EXTENSIVE HIGHER BASED STRATO CU
FIELD. THIS WILL SUPPORT LEANING ON THE LOWER END OF GUIDANCE MAX
TEMPS /LOW-MID 60S/.

WARMING IN THE 900-800MB LAYER THIS EVENING INTO THE OVERNIGHT
SHOULD ERODE ANY LINGERING INVERSION...OFFERING THE POSSIBILITY FOR
SOME CLEARING PRIOR TO THE ARRIVAL OF THE HIGH CLOUDS FROM THE NEXT
SYSTEM. THE LOW LEVELS ACROSS THE ERN GREAT LAKES WILL REMAIN RATHER
MOIST TODAY. A SE COMPONENT TO THE SFC WINDS TONIGHT AND INFLUENCE
FROM LAKE ERIE WILL THUS PROVIDE A CHANCE FOR SOME FOG AND/OR
STRATUS REDEVELOPMENT TOWARD DAYBREAK THURS.

LONG TERM...

ILL-DEFINED WARM FRONT LIFTING INTO NORTHERN LOWER MICHIGAN DURING
THURSDAY...WITH SOLID WARM ADVECTION TAKING PLACE OVER SOUTHEAST
MICHIGAN...AS 925 MB TEMPS WARM INTO THE UPPER TEENS TO AROUND 20 C
TOWARD 00Z FRIDAY. STILL...WITH SURFACE FLOW BACKED OUT OF THE
SOUTHEAST AND INCREASING/THICKENING CLOUDS WITH MOISTURE
ADVECTION/ISENTROPIC ASCENT...BOUNDARY LAYER MIXING WILL PROBABLY
COME UP JUST SHORT OF 925 MB...AND WILL CONTINUE WITH THE MORE
SUBDUED MAX TEMP FORECAST IN THE LOW TO MID 70S...WITH LIMITED RAIN
CHANCES...MAINLY ALONG/WEST OF U.S. 23 THROUGH THE DAY.

AN EVEN DEEPER MOISTURE SURGE THURSDAY NIGHT WITH BURGEONING HEIGHT
FALLS WILL ALLOW FOR DEVELOPING RAIN SHOWERS. THE TREND OF A SLOWER
AND STRONGER STORM SYSTEM FOR THE END OF THE WORK WEEK HAS CONTINUED
WITH THE 00Z MODELS...AS MERGING HEIGHT FALL CENTERS CONSOLIDATE
OVER THE CENTRAL CONUS ON THURSDAY...WITH POTENT UPPER WAVE/PV
ANOMALY OVER NORTHERN BRITISH COLUMBIA FORECASTED TO TRACK ALONG OR
SOUTH OF THE SOUTHERN MICHIGAN BORDER FRIDAY NIGHT PER
GFS/EURO...WHICH WILL SERVE AS THE ANCHOR/CENTER POINT OF THE
EASTERN NORTH AMERICAN LONGWAVE TROUGH DURING THE FIRST HALF OF THE
WEEKEND.

WITH SLOWER PASSAGE OF THE COLD FRONT ON FRIDAY...MAXES HAVE A
REASONABLE SHOT OF CLIMBING PAST 70 DEGREES BEFORE WE TAKE BIG NOSE
DIVE FOR THE WEEKEND...AS 850 MB TEMPS FALL BELOW ZERO...POTENTIALLY
AS COLD AS -4 C (SEE 00Z GFS). EVEN THOUGH INSTABILITY LOOKS MODEST
THURSDAY NIGHT-FRIDAY...SLIGHTLY NEGATIVE SFC-850 MB LI`S...ABOUT
500 J/KG OF CAPE DURING FRIDAY IS A BIT CONCERNING WITH 50 KNOTS
NOTED AT 850 MB...AND STRONG GUSTY WINDS APPEARS LIKELY WITH ANY
CONVECTIVE ACTIVITY.

CYCLONIC FLOW...STEEP LOW LEVEL LAPSE RATES...LAKE MICHIGAN
CONTRIBUTION ON SATURDAY SHOULD ASSURE SCATTERED TO NUMEROUS RAIN
SHOWERS...AS THERE ALSO LOOKS TO BE A PRONOUNCED SURFACE TROUGH
ROTATING THROUGH. COLD WESTERLY FLOW OFF LAKE MICHIGAN ON SUNDAY
STILL PROBABLY SUFFICIENT TO GENERATE SCATTERED LIGHT SHOWERS...WITH
MAXES HOLDING IN THE LOW TO MID 50S .

MARINE...

HIGH PRESSURE SITUATED OVER THE CENTRAL GREAT LAKES WILL PROVIDE
LIGHT WINDS AND LOW WAVES INTO THURSDAY MORNING. SOUTHERLY WINDS
WILL BEGIN TO PICK UP THURSDAY AFTERNOON...AS A STRONG COLD FRONT
APPROACHES. SOUTH WINDS UP TO 30 KNOTS OVER THE OPEN WATERS OF LAKE
HURON ARE ANTICIPATED FRIDAY MORNING...AS THE COLD FRONT MOVES
THROUGH DURING THE AFTERNOON HOURS. WARM AIR STREAMING INTO THE
REGION IS EXPECTED TO LEAD TO STABLE NEAR SURFACE PROFILES...AND
THUS KEEP WIND SPEEDS PREDOMINATELY BELOW 30 KNOTS. ANY CONVECTIVE
ACTIVITY WITH THE COLD FRONT COULD LEAD TO STRONGER WIND SPEEDS
HOWEVER. SEASONABLY COLD AIRMASS FOLLOWING THE COLD FRONT FRIDAY
NIGHT INTO THE WEEKEND WILL BE CONDUCIVE TO HIGHER WAVES ALONG WITH
NUMEROUS RAIN SHOWERS...AS WESTERLY WINDS GUST UP TO 30 KNOTS OVER
THE OPEN WATERS OF LAKE HURON.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....SC
SHORT TERM...SC
LONG TERM....SF
MARINE.......SF


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








000
FXUS63 KDTX 010722
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
322 AM EDT WED OCT 1 2014

.SHORT TERM...TODAY AND TONIGHT

THE UPPER LOW WHICH IMPACTED SE MI YESTERDAY IS SHOWN ON THE LATEST
WATER VAPOR LOOP ROTATING INTO THE MID ATLANTIC...TUCKED UNDER THE
UPPER RIDGE NOW EXPANDING INTO SRN QUEBEC. A MID LEVEL SHEAR AXIS
EXTENDING FROM THE DEPARTING UPPER LOW WILL LINGER OVER SE MI INTO
LATE AFTERNOON BEFORE BEING WASHED OUT BY SHORT WAVE RIDGING. THE
NET RESULT OF THE BUILDING MID LEVEL HEIGHTS OVER LOWER MI WILL BE
TO SUSTAIN LARGE SCALE SUBSIDENCE THROUGH MUCH OF THE SHORT TERM.
THE LATEST SFC ANALYSIS SHOWS A TROUGH AXIS EXTENDING ACROSS THE
THUMB AND SAGINAW VALLEY. ENHANCED CONVERGENCE ALONG THIS BOUNDARY
IS ALLOWING SOME DRIZZLE TO PERSIST. EXPANDING SFC HIGH PRESSURE
FROM THE NORTH WILL CONTINUE TO FORCE THIS BOUNDARY SOUTH THIS
MORNING...WITH IT EXPECTED TO WASH OUT COMPLETELY BY AFTERNOON AS
THE SFC HIGH PRESSURE TAKES HOLD.

THE CLOUD AND FOG FORECAST WILL REMAIN THE MORE CHALLENGING ASPECT
OF THE SHORT TERM. ASIDE FROM LENAWEE AND MONROE COUNTIES WHICH
EXPERIENCED A PERIOD OF CLEAR SKIES...CLOUDS REMAINED SOLID
ACROSS THE FORECAST AREA OVERNIGHT. E-NE LOW LEVEL WINDS DURING
THE NIGHT ADVECTED VERY MOIST AIR IN FROM SRN ONTARIO /WHERE SFC
DEWPOINTS WERE IN THE UPPER 50S YESTERDAY AFTERNOON/. THE RESULT
HAS BEEN A 200-400 FT STRATUS DECK BLANKETING MOST OF THE NRN TWO
THIRDS OF THE FORECAST AREA. WEAKENING LOW LEVEL FLOW AND A
MOISTURE RICH BOUNDARY LAYER MAY CONTINUE TO LOWER THE CLOUD BASES
TOWARD DAYBREAK...WHICH WILL SUSTAIN SOME FOG /ESPECIALLY IN THE
HIGHER TERRAIN OF THE IRISH HILLS/. MODEL SOLUTIONS SUGGEST
DAYTIME HEATING AND LOW LEVEL ANTICYCLONIC FLOW WILL LEAD TO
CLEARING THIS AFTERNOON. HOWEVER... THE 00Z DTX SOUNDING SHOWED A
SECONDARY INVERSION /RATHER DEEP/ BASED NEAR 800MB WHICH NONE OF
THE MODEL SOLUTIONS RESOLVED. WITH SOME THERMAL TROUGHING NEAR
850MB FORECAST TO LINGER THROUGH THE AFTERNOON...DAYTIME HEATING
WILL MOST LIKELY LEAD TO AN EXTENSIVE HIGHER BASED STRATO CU
FIELD. THIS WILL SUPPORT LEANING ON THE LOWER END OF GUIDANCE MAX
TEMPS /LOW-MID 60S/.

WARMING IN THE 900-800MB LAYER THIS EVENING INTO THE OVERNIGHT
SHOULD ERODE ANY LINGERING INVERSION...OFFERING THE POSSIBILITY FOR
SOME CLEARING PRIOR TO THE ARRIVAL OF THE HIGH CLOUDS FROM THE NEXT
SYSTEM. THE LOW LEVELS ACROSS THE ERN GREAT LAKES WILL REMAIN RATHER
MOIST TODAY. A SE COMPONENT TO THE SFC WINDS TONIGHT AND INFLUENCE
FROM LAKE ERIE WILL THUS PROVIDE A CHANCE FOR SOME FOG AND/OR
STRATUS REDEVELOPMENT TOWARD DAYBREAK THURS.

&&

.LONG TERM...

ILL-DEFINED WARM FRONT LIFTING INTO NORTHERN LOWER MICHIGAN DURING
THURSDAY...WITH SOLID WARM ADVECTION TAKING PLACE OVER SOUTHEAST
MICHIGAN...AS 925 MB TEMPS WARM INTO THE UPPER TEENS TO AROUND 20 C
TOWARD 00Z FRIDAY. STILL...WITH SURFACE FLOW BACKED OUT OF THE
SOUTHEAST AND INCREASING/THICKENING CLOUDS WITH MOISTURE
ADVECTION/ISENTROPIC ASCENT...BOUNDARY LAYER MIXING WILL PROBABLY
COME UP JUST SHORT OF 925 MB...AND WILL CONTINUE WITH THE MORE
SUBDUED MAX TEMP FORECAST IN THE LOW TO MID 70S...WITH LIMITED RAIN
CHANCES...MAINLY ALONG/WEST OF U.S. 23 THROUGH THE DAY.

AN EVEN DEEPER MOISTURE SURGE THURSDAY NIGHT WITH BURGEONING HEIGHT
FALLS WILL ALLOW FOR DEVELOPING RAIN SHOWERS. THE TREND OF A SLOWER
AND STRONGER STORM SYSTEM FOR THE END OF THE WORK WEEK HAS CONTINUED
WITH THE 00Z MODELS...AS MERGING HEIGHT FALL CENTERS CONSOLIDATE
OVER THE CENTRAL CONUS ON THURSDAY...WITH POTENT UPPER WAVE/PV
ANOMALY OVER NORTHERN BRITISH COLUMBIA FORECASTED TO TRACK ALONG OR
SOUTH OF THE SOUTHERN MICHIGAN BORDER FRIDAY NIGHT PER
GFS/EURO...WHICH WILL SERVE AS THE ANCHOR/CENTER POINT OF THE
EASTERN NORTH AMERICAN LONGWAVE TROUGH DURING THE FIRST HALF OF THE
WEEKEND.

WITH SLOWER PASSAGE OF THE COLD FRONT ON FRIDAY...MAXES HAVE A
REASONABLE SHOT OF CLIMBING PAST 70 DEGREES BEFORE WE TAKE BIG NOSE
DIVE FOR THE WEEKEND...AS 850 MB TEMPS FALL BELOW ZERO...POTENTIALLY
AS COLD AS -4 C (SEE 00Z GFS). EVEN THOUGH INSTABILITY LOOKS MODEST
THURSDAY NIGHT-FRIDAY...SLIGHTLY NEGATIVE SFC-850 MB LI`S...ABOUT
500 J/KG OF CAPE DURING FRIDAY IS A BIT CONCERNING WITH 50 KNOTS
NOTED AT 850 MB...AND STRONG GUSTY WINDS APPEARS LIKELY WITH ANY
CONVECTIVE ACTIVITY.

CYCLONIC FLOW...STEEP LOW LEVEL LAPSE RATES...LAKE MICHIGAN
CONTRIBUTION ON SATURDAY SHOULD ASSURE SCATTERED TO NUMEROUS RAIN
SHOWERS...AS THERE ALSO LOOKS TO BE A PRONOUNCED SURFACE TROUGH
ROTATING THROUGH. COLD WESTERLY FLOW OFF LAKE MICHIGAN ON SUNDAY
STILL PROBABLY SUFFICIENT TO GENERATE SCATTERED LIGHT SHOWERS...WITH
MAXES HOLDING IN THE LOW TO MID 50S .

&&

.MARINE...

HIGH PRESSURE SITUATED OVER THE CENTRAL GREAT LAKES WILL PROVIDE
LIGHT WINDS AND LOW WAVES INTO THURSDAY MORNING. SOUTHERLY WINDS
WILL BEGIN TO PICK UP THURSDAY AFTERNOON...AS A STRONG COLD FRONT
APPROACHES. SOUTH WINDS UP TO 30 KNOTS OVER THE OPEN WATERS OF LAKE
HURON ARE ANTICIPATED FRIDAY MORNING...AS THE COLD FRONT MOVES
THROUGH DURING THE AFTERNOON HOURS. WARM AIR STREAMING INTO THE
REGION IS EXPECTED TO LEAD TO STABLE NEAR SURFACE PROFILES...AND
THUS KEEP WIND SPEEDS PREDOMINATELY BELOW 30 KNOTS. ANY CONVECTIVE
ACTIVITY WITH THE COLD FRONT COULD LEAD TO STRONGER WIND SPEEDS
HOWEVER. SEASONABLY COLD AIRMASS FOLLOWING THE COLD FRONT FRIDAY
NIGHT INTO THE WEEKEND WILL BE CONDUCIVE TO HIGHER WAVES ALONG WITH
NUMEROUS RAIN SHOWERS...AS WESTERLY WINDS GUST UP TO 30 KNOTS OVER
THE OPEN WATERS OF LAKE HURON.

&&

.AVIATION...ISSUED 1155 PM EDT TUE SEP 30 2014

//DISCUSSION...

IFR CIGS CONTINUE TO SPREAD SOUTHWARD THROUGH THE CWA WITHIN MOIST
CYCLONIC FLOW ON WEST SIDE OF LOW PRESSURE. CIGS/VSBYS ARE EXPECTED
TO EDGE DOWN THROUGH THE NIGHT WITH IFR/LIFR COMMON BY DAWN AS LOW
LEVEL MOISTURE REMAINS TRAPPED UNDER LOWERING INVERSION. CONDITIONS
WILL THEN GRADUALLY IMPROVE ON WEDNESDAY AS THE AFOREMENTIONED LOW
SHIFTS TO THE EAST/SOUTHEAST.

FOR DTW...EXPECT CIGS TO LOWER BELOW 1000 FEET BETWEEN 06Z-08Z WITH
AREAS OF FOG POSSIBLE AFTER 08Z. THIS WILL LINGER THROUGH 14Z OR
SO...BEFORE GRADUAL IMPROVEMENT IN CIGS/VSBYS ENSUES FOR THE REST OF
THE FORECAST PERIOD.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET THROUGH WEDNESDAY
MORNING...WITH MEDIUM CONFIDENCE FOR WEDNESDAY AFTERNOON/EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO HARBOR BEACH...UNTIL 4 AM WEDNESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...SC
LONG TERM....SF
MARINE.......SF
AVIATION.....DG


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







000
FXUS63 KDTX 010722
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
322 AM EDT WED OCT 1 2014

.SHORT TERM...TODAY AND TONIGHT

THE UPPER LOW WHICH IMPACTED SE MI YESTERDAY IS SHOWN ON THE LATEST
WATER VAPOR LOOP ROTATING INTO THE MID ATLANTIC...TUCKED UNDER THE
UPPER RIDGE NOW EXPANDING INTO SRN QUEBEC. A MID LEVEL SHEAR AXIS
EXTENDING FROM THE DEPARTING UPPER LOW WILL LINGER OVER SE MI INTO
LATE AFTERNOON BEFORE BEING WASHED OUT BY SHORT WAVE RIDGING. THE
NET RESULT OF THE BUILDING MID LEVEL HEIGHTS OVER LOWER MI WILL BE
TO SUSTAIN LARGE SCALE SUBSIDENCE THROUGH MUCH OF THE SHORT TERM.
THE LATEST SFC ANALYSIS SHOWS A TROUGH AXIS EXTENDING ACROSS THE
THUMB AND SAGINAW VALLEY. ENHANCED CONVERGENCE ALONG THIS BOUNDARY
IS ALLOWING SOME DRIZZLE TO PERSIST. EXPANDING SFC HIGH PRESSURE
FROM THE NORTH WILL CONTINUE TO FORCE THIS BOUNDARY SOUTH THIS
MORNING...WITH IT EXPECTED TO WASH OUT COMPLETELY BY AFTERNOON AS
THE SFC HIGH PRESSURE TAKES HOLD.

THE CLOUD AND FOG FORECAST WILL REMAIN THE MORE CHALLENGING ASPECT
OF THE SHORT TERM. ASIDE FROM LENAWEE AND MONROE COUNTIES WHICH
EXPERIENCED A PERIOD OF CLEAR SKIES...CLOUDS REMAINED SOLID
ACROSS THE FORECAST AREA OVERNIGHT. E-NE LOW LEVEL WINDS DURING
THE NIGHT ADVECTED VERY MOIST AIR IN FROM SRN ONTARIO /WHERE SFC
DEWPOINTS WERE IN THE UPPER 50S YESTERDAY AFTERNOON/. THE RESULT
HAS BEEN A 200-400 FT STRATUS DECK BLANKETING MOST OF THE NRN TWO
THIRDS OF THE FORECAST AREA. WEAKENING LOW LEVEL FLOW AND A
MOISTURE RICH BOUNDARY LAYER MAY CONTINUE TO LOWER THE CLOUD BASES
TOWARD DAYBREAK...WHICH WILL SUSTAIN SOME FOG /ESPECIALLY IN THE
HIGHER TERRAIN OF THE IRISH HILLS/. MODEL SOLUTIONS SUGGEST
DAYTIME HEATING AND LOW LEVEL ANTICYCLONIC FLOW WILL LEAD TO
CLEARING THIS AFTERNOON. HOWEVER... THE 00Z DTX SOUNDING SHOWED A
SECONDARY INVERSION /RATHER DEEP/ BASED NEAR 800MB WHICH NONE OF
THE MODEL SOLUTIONS RESOLVED. WITH SOME THERMAL TROUGHING NEAR
850MB FORECAST TO LINGER THROUGH THE AFTERNOON...DAYTIME HEATING
WILL MOST LIKELY LEAD TO AN EXTENSIVE HIGHER BASED STRATO CU
FIELD. THIS WILL SUPPORT LEANING ON THE LOWER END OF GUIDANCE MAX
TEMPS /LOW-MID 60S/.

WARMING IN THE 900-800MB LAYER THIS EVENING INTO THE OVERNIGHT
SHOULD ERODE ANY LINGERING INVERSION...OFFERING THE POSSIBILITY FOR
SOME CLEARING PRIOR TO THE ARRIVAL OF THE HIGH CLOUDS FROM THE NEXT
SYSTEM. THE LOW LEVELS ACROSS THE ERN GREAT LAKES WILL REMAIN RATHER
MOIST TODAY. A SE COMPONENT TO THE SFC WINDS TONIGHT AND INFLUENCE
FROM LAKE ERIE WILL THUS PROVIDE A CHANCE FOR SOME FOG AND/OR
STRATUS REDEVELOPMENT TOWARD DAYBREAK THURS.

&&

.LONG TERM...

ILL-DEFINED WARM FRONT LIFTING INTO NORTHERN LOWER MICHIGAN DURING
THURSDAY...WITH SOLID WARM ADVECTION TAKING PLACE OVER SOUTHEAST
MICHIGAN...AS 925 MB TEMPS WARM INTO THE UPPER TEENS TO AROUND 20 C
TOWARD 00Z FRIDAY. STILL...WITH SURFACE FLOW BACKED OUT OF THE
SOUTHEAST AND INCREASING/THICKENING CLOUDS WITH MOISTURE
ADVECTION/ISENTROPIC ASCENT...BOUNDARY LAYER MIXING WILL PROBABLY
COME UP JUST SHORT OF 925 MB...AND WILL CONTINUE WITH THE MORE
SUBDUED MAX TEMP FORECAST IN THE LOW TO MID 70S...WITH LIMITED RAIN
CHANCES...MAINLY ALONG/WEST OF U.S. 23 THROUGH THE DAY.

AN EVEN DEEPER MOISTURE SURGE THURSDAY NIGHT WITH BURGEONING HEIGHT
FALLS WILL ALLOW FOR DEVELOPING RAIN SHOWERS. THE TREND OF A SLOWER
AND STRONGER STORM SYSTEM FOR THE END OF THE WORK WEEK HAS CONTINUED
WITH THE 00Z MODELS...AS MERGING HEIGHT FALL CENTERS CONSOLIDATE
OVER THE CENTRAL CONUS ON THURSDAY...WITH POTENT UPPER WAVE/PV
ANOMALY OVER NORTHERN BRITISH COLUMBIA FORECASTED TO TRACK ALONG OR
SOUTH OF THE SOUTHERN MICHIGAN BORDER FRIDAY NIGHT PER
GFS/EURO...WHICH WILL SERVE AS THE ANCHOR/CENTER POINT OF THE
EASTERN NORTH AMERICAN LONGWAVE TROUGH DURING THE FIRST HALF OF THE
WEEKEND.

WITH SLOWER PASSAGE OF THE COLD FRONT ON FRIDAY...MAXES HAVE A
REASONABLE SHOT OF CLIMBING PAST 70 DEGREES BEFORE WE TAKE BIG NOSE
DIVE FOR THE WEEKEND...AS 850 MB TEMPS FALL BELOW ZERO...POTENTIALLY
AS COLD AS -4 C (SEE 00Z GFS). EVEN THOUGH INSTABILITY LOOKS MODEST
THURSDAY NIGHT-FRIDAY...SLIGHTLY NEGATIVE SFC-850 MB LI`S...ABOUT
500 J/KG OF CAPE DURING FRIDAY IS A BIT CONCERNING WITH 50 KNOTS
NOTED AT 850 MB...AND STRONG GUSTY WINDS APPEARS LIKELY WITH ANY
CONVECTIVE ACTIVITY.

CYCLONIC FLOW...STEEP LOW LEVEL LAPSE RATES...LAKE MICHIGAN
CONTRIBUTION ON SATURDAY SHOULD ASSURE SCATTERED TO NUMEROUS RAIN
SHOWERS...AS THERE ALSO LOOKS TO BE A PRONOUNCED SURFACE TROUGH
ROTATING THROUGH. COLD WESTERLY FLOW OFF LAKE MICHIGAN ON SUNDAY
STILL PROBABLY SUFFICIENT TO GENERATE SCATTERED LIGHT SHOWERS...WITH
MAXES HOLDING IN THE LOW TO MID 50S .

&&

.MARINE...

HIGH PRESSURE SITUATED OVER THE CENTRAL GREAT LAKES WILL PROVIDE
LIGHT WINDS AND LOW WAVES INTO THURSDAY MORNING. SOUTHERLY WINDS
WILL BEGIN TO PICK UP THURSDAY AFTERNOON...AS A STRONG COLD FRONT
APPROACHES. SOUTH WINDS UP TO 30 KNOTS OVER THE OPEN WATERS OF LAKE
HURON ARE ANTICIPATED FRIDAY MORNING...AS THE COLD FRONT MOVES
THROUGH DURING THE AFTERNOON HOURS. WARM AIR STREAMING INTO THE
REGION IS EXPECTED TO LEAD TO STABLE NEAR SURFACE PROFILES...AND
THUS KEEP WIND SPEEDS PREDOMINATELY BELOW 30 KNOTS. ANY CONVECTIVE
ACTIVITY WITH THE COLD FRONT COULD LEAD TO STRONGER WIND SPEEDS
HOWEVER. SEASONABLY COLD AIRMASS FOLLOWING THE COLD FRONT FRIDAY
NIGHT INTO THE WEEKEND WILL BE CONDUCIVE TO HIGHER WAVES ALONG WITH
NUMEROUS RAIN SHOWERS...AS WESTERLY WINDS GUST UP TO 30 KNOTS OVER
THE OPEN WATERS OF LAKE HURON.

&&

.AVIATION...ISSUED 1155 PM EDT TUE SEP 30 2014

//DISCUSSION...

IFR CIGS CONTINUE TO SPREAD SOUTHWARD THROUGH THE CWA WITHIN MOIST
CYCLONIC FLOW ON WEST SIDE OF LOW PRESSURE. CIGS/VSBYS ARE EXPECTED
TO EDGE DOWN THROUGH THE NIGHT WITH IFR/LIFR COMMON BY DAWN AS LOW
LEVEL MOISTURE REMAINS TRAPPED UNDER LOWERING INVERSION. CONDITIONS
WILL THEN GRADUALLY IMPROVE ON WEDNESDAY AS THE AFOREMENTIONED LOW
SHIFTS TO THE EAST/SOUTHEAST.

FOR DTW...EXPECT CIGS TO LOWER BELOW 1000 FEET BETWEEN 06Z-08Z WITH
AREAS OF FOG POSSIBLE AFTER 08Z. THIS WILL LINGER THROUGH 14Z OR
SO...BEFORE GRADUAL IMPROVEMENT IN CIGS/VSBYS ENSUES FOR THE REST OF
THE FORECAST PERIOD.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET THROUGH WEDNESDAY
MORNING...WITH MEDIUM CONFIDENCE FOR WEDNESDAY AFTERNOON/EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO HARBOR BEACH...UNTIL 4 AM WEDNESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...SC
LONG TERM....SF
MARINE.......SF
AVIATION.....DG


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








000
FXUS63 KDTX 010358 CCA
AFDDTX

AREA FORECAST DISCUSSION...CORRECTED TYPO
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1155 PM EDT TUE SEP 30 2014


.AVIATION...

//DISCUSSION...

IFR CIGS CONTINUE TO SPREAD SOUTHWARD THROUGH THE CWA WITHIN MOIST
CYCLONIC FLOW ON WEST SIDE OF LOW PRESSURE. CIGS/VSBYS ARE EXPECTED
TO EDGE DOWN THROUGH THE NIGHT WITH IFR/LIFR COMMON BY DAWN AS LOW
LEVEL MOISTURE REMAINS TRAPPED UNDER LOWERING INVERSION. CONDITIONS
WILL THEN GRADUALLY IMPROVE ON WEDNESDAY AS THE AFOREMENTIONED LOW
SHIFTS TO THE EAST/SOUTHEAST.

FOR DTW...EXPECT CIGS TO LOWER BELOW 1000 FEET BETWEEN 06Z-08Z WITH
AREAS OF FOG POSSIBLE AFTER 08Z. THIS WILL LINGER THROUGH 14Z OR
SO...BEFORE GRADUAL IMPROVEMENT IN CIGS/VSBYS ENSUES FOR THE REST OF
THE FORECAST PERIOD.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET THROUGH WEDNESDAY
MORNING...WITH MEDIUM CONFIDENCE FOR WEDNESDAY AFTERNOON/EVENING.

&&

.PREV DISCUSSION...ISSUED 354 PM EDT TUE SEP 30 2014

SHORT TERM...TONIGHT

CURRENT MODEL RUNS ARE STILL SHOWING SURFACE RIDGING TO BUILD ACROSS
THE REGION TONIGHT HELPING TO PUT AN END TO ANY LINGERING DRIZZLE
AND RAIN SHOWERS BY EARLY EVENING. ORIGINAL THINKING WAS FOR CLOUDS
TO ALSO DIMINISH SLIGHTLY...HOWEVER...WITH ABUNDANT MOISTURE AROUND
FROM RAIN AND DRIZZLE THROUGHOUT THE DAY...CONFIDENCE IS HIGH IN CLOUD
COVER REMAINING OVERCAST TONIGHT. THIS LOW LEVEL MOISTURE COMBINED
WITH SOME WEAK WARM AIR ADVECTION WILL RESULT IN A HIGHER
PROBABILITY OF LOW STRATUS AND EVEN SOME FOG DEVELOPMENT ESPECIALLY
IN LOW LYING AREAS. ONLY MAJOR CONCERN TO WATCH OUT FOR DURING THE
NEXT FORECAST SHIFT IS THE UNCERTAINTY ABOUT HOW DENSE THE FOG WILL BE
OVERNIGHT. OVERCAST SKIES OVERNIGHT WILL RESULT IN TEMPERATURES TO
ONLY DROP A FEW DEGREES FROM TUESDAYS HIGH TEMPS INTO THE UPPER 40S
AND LOW 50S ACROSS SOUTHEAST MICHIGAN.

LONG TERM...WEDNESDAY THROUGH MONDAY

LONGWAVE PATTERN TO UNDERGO SOME BIG CHANGES THROUGH THE REST OF THE
WEEK LEADING TO A VERY COOL WEEKEND AS A DEEP TROUGH OVERTAKES THE
REGION. THE MIDWEEK TIME FRAME WILL BE THE TRANSITION PERIOD FOR THE
PATTERN AS THE FIRST STRONG WAVE COMES ASHORE THE NW CONUS. THIS
WILL CARVE OUT A TROUGH OVER THE MOUNTAIN WEST WHICH WILL ABSORB A
CUTOFF LOW AS IT MOVES FURTHER EAST. NARROW RIDGE AXIS IN ADVANCE OF
THE TROUGH WILL PASS OVER THE GREAT LAKES WEDNESDAY. MEANWHILE AT
THE SFC...SOUTHERN PERIPHERY OF HIGH PRESSURE OVER ONTARIO/QUEBEC
REMAINS IN CONTROL AT THE SFC BUT WILL DRIFT EAST LOOSENING ITS
GRIP. COOL EASTERLY FLOW WILL BE REPLACED WITH WARMER AND MOISTER
SOUTH/SOUTHWEST FLOW AS THE DEEPENING TROUGH REACHES THE PLAINS
STATES. PATTERN STALLS OVER THE UPPER MISSISSIPPI VALLEY AS A STRONG
WAVE DIVES THROUGH THE TROUGH CHANGING IT FROM A POSITIVE TO NEUTRAL
TILT. AS THE WAVE LIFTS NE OUT OF THE TROUGH...CYCLOGENESIS WILL
ENSUE ALONG A COLD FRONT EXTENDING FROM ONTARIO DOWN INTO OKLAHOMA.
THIS SFC LOW WILL UNDERGO RAPID INTENSIFICATION...DEEPENING FROM
1004MB 18Z THURSDAY DOWN TO 988MB 12Z FRIDAY WHICH IS NEARLY 1
MB/HR. BUT THIS SFC LOW WILL HAVE LITTLE FORWARD PROPAGATION DUE TO
THE UPPER LEVEL TROUGH STALLING.

NOW FOR WHAT THIS MEANS FOR SE MI WEDNESDAY AND THURSDAY. WEDNESDAY
WILL START OFF VERY CLOUDY AS MODEL CONSENSUS KEEPS A VERY MOISTURE
LADEN BL UNDER A STRONG BUT WEAKENING INVERSION. INCREASING HEIGHTS
WITH RIDGE AXIS OVERHEAD WILL PROMOTE SOME WARMING ALONG WITH THE
MORE FAVORABLE WIND DIRECTION. EAST WINDS WILL VEER AROUND SOUTH
LATE IN THE DAY BECOMING SOUTHWEST OVERNIGHT. CURRENT THINKING KEEPS
TEMPS IN THE MID 60S. WILL BE SOME ADDITIONAL POTENTIAL FOR TEMPS TO
JUMP A DEGREE OR TWO WITH WARMER AIR ALOFT BUT MODEL SOUNDINGS SHOW
MIXING DEPTHS STRUGGLING TO TAP INTO THAT AIR. THERE WILL LIKELY BE
A SHARP GRADIENT IN PRECIPITATION ON THURSDAY AS A PREFRONTAL LINE
OF SHOWERS APPROACHES SE MI. THE RIDGE WILL HOLD IT TO THE WEST FOR
MOST OF THE DAY WITH ONLY OUR WESTERN COUNTIES HAVING A CHANCE FOR
ANY SHOWERS. THE STRONGEST OF THE SHORTWAVES THUS FAR WILL SURGE
THROUGH THE TROUGH FORCING THE COLD FRONT THROUGH LOWER MI LATE
THURSDAY NIGHT INTO FRIDAY. GOOD SW FLOW AHEAD OF THE FRONT WILL
RAMP UP WAA WITH TEMPS IN THE MID 70S WHICH WILL DROP OFF
SIGNIFICANTLY POST FRONTAL AS WE EXPERIENCED TODAY FROM THE MOST
RECENT COLD FRONT.

DEEPENING LOW PRESSURE AND ASSOCIATED COLD FRONT WILL CROSS THROUGH
THE STATE ON FRIDAY. THIS FEATURE WILL SPREAD RAIN...BRISK
WINDS...AND A SHARP TEMPERATURE DROP TO THE AREA. EXPECT LOW
STRATUS...DRIZZLE...AND MUCH COOLER TEMPERATURES FOR THE WEEKEND IN
THE POST FRONTAL/UPPER TROUGH PATTERN. TEMPS WILL BE HOVERING AROUND
10 DEGREES BELOW NORMAL FOR THE WEEKEND INTO EARLY NEXT WEEK.

MARINE...

A TIGHT NORTHERLY GRADIENT REMAINS OVER CENTRAL LAKE HURON KEEPING
WIND SPEEDS UP LONGER INTO THE AFTERNOON. THESE WINDS WILL CONTINUE
TO BUILD WAVES UP TO SMALL CRAFT CRITERIA ALONG THE LAKE HURON
SHORELINE OF THE THUMB. SMALL CRAFT ADVISORIES WILL CONTINUE THROUGH
THIS EVENING TO ACCOUNT FOR THAT. WINDS WILL DIMINISH TONIGHT AS
HIGH PRESSURE LESSENS THE GRADIENT OVER THE LAKES BUT THE PERSISTENT
NORTHEAST FLOW WILL KEEP SOME ELEVATED WAVES HEIGHTS INTO THE
OVERNIGHT HOURS. LIGHT WINDS AND LOW WAVES WILL PERSIST WEDNESDAY
INTO THURSDAY. HOWEVER...SOUTHERLY WINDS DEVELOPING AHEAD OF A COLD
FRONT LATE THURSDAY COULD RESULT IN WINDS UP TO 30 KNOTS OVER THE
OPEN WATERS OF LAKE HURON THURSDAY NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO HARBOR BEACH...UNTIL 4 AM WEDNESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....DG
SHORT TERM...RK
LONG TERM....DRK/MM
MARINE.......DRK


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










000
FXUS63 KDTX 010358 CCA
AFDDTX

AREA FORECAST DISCUSSION...CORRECTED TYPO
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1155 PM EDT TUE SEP 30 2014


.AVIATION...

//DISCUSSION...

IFR CIGS CONTINUE TO SPREAD SOUTHWARD THROUGH THE CWA WITHIN MOIST
CYCLONIC FLOW ON WEST SIDE OF LOW PRESSURE. CIGS/VSBYS ARE EXPECTED
TO EDGE DOWN THROUGH THE NIGHT WITH IFR/LIFR COMMON BY DAWN AS LOW
LEVEL MOISTURE REMAINS TRAPPED UNDER LOWERING INVERSION. CONDITIONS
WILL THEN GRADUALLY IMPROVE ON WEDNESDAY AS THE AFOREMENTIONED LOW
SHIFTS TO THE EAST/SOUTHEAST.

FOR DTW...EXPECT CIGS TO LOWER BELOW 1000 FEET BETWEEN 06Z-08Z WITH
AREAS OF FOG POSSIBLE AFTER 08Z. THIS WILL LINGER THROUGH 14Z OR
SO...BEFORE GRADUAL IMPROVEMENT IN CIGS/VSBYS ENSUES FOR THE REST OF
THE FORECAST PERIOD.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET THROUGH WEDNESDAY
MORNING...WITH MEDIUM CONFIDENCE FOR WEDNESDAY AFTERNOON/EVENING.

&&

.PREV DISCUSSION...ISSUED 354 PM EDT TUE SEP 30 2014

SHORT TERM...TONIGHT

CURRENT MODEL RUNS ARE STILL SHOWING SURFACE RIDGING TO BUILD ACROSS
THE REGION TONIGHT HELPING TO PUT AN END TO ANY LINGERING DRIZZLE
AND RAIN SHOWERS BY EARLY EVENING. ORIGINAL THINKING WAS FOR CLOUDS
TO ALSO DIMINISH SLIGHTLY...HOWEVER...WITH ABUNDANT MOISTURE AROUND
FROM RAIN AND DRIZZLE THROUGHOUT THE DAY...CONFIDENCE IS HIGH IN CLOUD
COVER REMAINING OVERCAST TONIGHT. THIS LOW LEVEL MOISTURE COMBINED
WITH SOME WEAK WARM AIR ADVECTION WILL RESULT IN A HIGHER
PROBABILITY OF LOW STRATUS AND EVEN SOME FOG DEVELOPMENT ESPECIALLY
IN LOW LYING AREAS. ONLY MAJOR CONCERN TO WATCH OUT FOR DURING THE
NEXT FORECAST SHIFT IS THE UNCERTAINTY ABOUT HOW DENSE THE FOG WILL BE
OVERNIGHT. OVERCAST SKIES OVERNIGHT WILL RESULT IN TEMPERATURES TO
ONLY DROP A FEW DEGREES FROM TUESDAYS HIGH TEMPS INTO THE UPPER 40S
AND LOW 50S ACROSS SOUTHEAST MICHIGAN.

LONG TERM...WEDNESDAY THROUGH MONDAY

LONGWAVE PATTERN TO UNDERGO SOME BIG CHANGES THROUGH THE REST OF THE
WEEK LEADING TO A VERY COOL WEEKEND AS A DEEP TROUGH OVERTAKES THE
REGION. THE MIDWEEK TIME FRAME WILL BE THE TRANSITION PERIOD FOR THE
PATTERN AS THE FIRST STRONG WAVE COMES ASHORE THE NW CONUS. THIS
WILL CARVE OUT A TROUGH OVER THE MOUNTAIN WEST WHICH WILL ABSORB A
CUTOFF LOW AS IT MOVES FURTHER EAST. NARROW RIDGE AXIS IN ADVANCE OF
THE TROUGH WILL PASS OVER THE GREAT LAKES WEDNESDAY. MEANWHILE AT
THE SFC...SOUTHERN PERIPHERY OF HIGH PRESSURE OVER ONTARIO/QUEBEC
REMAINS IN CONTROL AT THE SFC BUT WILL DRIFT EAST LOOSENING ITS
GRIP. COOL EASTERLY FLOW WILL BE REPLACED WITH WARMER AND MOISTER
SOUTH/SOUTHWEST FLOW AS THE DEEPENING TROUGH REACHES THE PLAINS
STATES. PATTERN STALLS OVER THE UPPER MISSISSIPPI VALLEY AS A STRONG
WAVE DIVES THROUGH THE TROUGH CHANGING IT FROM A POSITIVE TO NEUTRAL
TILT. AS THE WAVE LIFTS NE OUT OF THE TROUGH...CYCLOGENESIS WILL
ENSUE ALONG A COLD FRONT EXTENDING FROM ONTARIO DOWN INTO OKLAHOMA.
THIS SFC LOW WILL UNDERGO RAPID INTENSIFICATION...DEEPENING FROM
1004MB 18Z THURSDAY DOWN TO 988MB 12Z FRIDAY WHICH IS NEARLY 1
MB/HR. BUT THIS SFC LOW WILL HAVE LITTLE FORWARD PROPAGATION DUE TO
THE UPPER LEVEL TROUGH STALLING.

NOW FOR WHAT THIS MEANS FOR SE MI WEDNESDAY AND THURSDAY. WEDNESDAY
WILL START OFF VERY CLOUDY AS MODEL CONSENSUS KEEPS A VERY MOISTURE
LADEN BL UNDER A STRONG BUT WEAKENING INVERSION. INCREASING HEIGHTS
WITH RIDGE AXIS OVERHEAD WILL PROMOTE SOME WARMING ALONG WITH THE
MORE FAVORABLE WIND DIRECTION. EAST WINDS WILL VEER AROUND SOUTH
LATE IN THE DAY BECOMING SOUTHWEST OVERNIGHT. CURRENT THINKING KEEPS
TEMPS IN THE MID 60S. WILL BE SOME ADDITIONAL POTENTIAL FOR TEMPS TO
JUMP A DEGREE OR TWO WITH WARMER AIR ALOFT BUT MODEL SOUNDINGS SHOW
MIXING DEPTHS STRUGGLING TO TAP INTO THAT AIR. THERE WILL LIKELY BE
A SHARP GRADIENT IN PRECIPITATION ON THURSDAY AS A PREFRONTAL LINE
OF SHOWERS APPROACHES SE MI. THE RIDGE WILL HOLD IT TO THE WEST FOR
MOST OF THE DAY WITH ONLY OUR WESTERN COUNTIES HAVING A CHANCE FOR
ANY SHOWERS. THE STRONGEST OF THE SHORTWAVES THUS FAR WILL SURGE
THROUGH THE TROUGH FORCING THE COLD FRONT THROUGH LOWER MI LATE
THURSDAY NIGHT INTO FRIDAY. GOOD SW FLOW AHEAD OF THE FRONT WILL
RAMP UP WAA WITH TEMPS IN THE MID 70S WHICH WILL DROP OFF
SIGNIFICANTLY POST FRONTAL AS WE EXPERIENCED TODAY FROM THE MOST
RECENT COLD FRONT.

DEEPENING LOW PRESSURE AND ASSOCIATED COLD FRONT WILL CROSS THROUGH
THE STATE ON FRIDAY. THIS FEATURE WILL SPREAD RAIN...BRISK
WINDS...AND A SHARP TEMPERATURE DROP TO THE AREA. EXPECT LOW
STRATUS...DRIZZLE...AND MUCH COOLER TEMPERATURES FOR THE WEEKEND IN
THE POST FRONTAL/UPPER TROUGH PATTERN. TEMPS WILL BE HOVERING AROUND
10 DEGREES BELOW NORMAL FOR THE WEEKEND INTO EARLY NEXT WEEK.

MARINE...

A TIGHT NORTHERLY GRADIENT REMAINS OVER CENTRAL LAKE HURON KEEPING
WIND SPEEDS UP LONGER INTO THE AFTERNOON. THESE WINDS WILL CONTINUE
TO BUILD WAVES UP TO SMALL CRAFT CRITERIA ALONG THE LAKE HURON
SHORELINE OF THE THUMB. SMALL CRAFT ADVISORIES WILL CONTINUE THROUGH
THIS EVENING TO ACCOUNT FOR THAT. WINDS WILL DIMINISH TONIGHT AS
HIGH PRESSURE LESSENS THE GRADIENT OVER THE LAKES BUT THE PERSISTENT
NORTHEAST FLOW WILL KEEP SOME ELEVATED WAVES HEIGHTS INTO THE
OVERNIGHT HOURS. LIGHT WINDS AND LOW WAVES WILL PERSIST WEDNESDAY
INTO THURSDAY. HOWEVER...SOUTHERLY WINDS DEVELOPING AHEAD OF A COLD
FRONT LATE THURSDAY COULD RESULT IN WINDS UP TO 30 KNOTS OVER THE
OPEN WATERS OF LAKE HURON THURSDAY NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO HARBOR BEACH...UNTIL 4 AM WEDNESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....DG
SHORT TERM...RK
LONG TERM....DRK/MM
MARINE.......DRK


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











000
FXUS63 KDTX 010355
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1155 PM EDT TUE SEP 30 2014


.AVIATION...

//DISCUSSION...

VFR CIGS CONTINUE TO SPREAD SOUTHWARD THROUGH THE CWA WITHIN MOIST
CYCLONIC FLOW ON WEST SIDE OF LOW PRESSURE. CIGS/VSBYS ARE EXPECTED
TO EDGE DOWN THROUGH THE NIGHT WITH IFR/LIFR COMMON BY DAWN AS LOW
LEVEL MOISTURE REMAINS TRAPPED UNDER LOWERING INVERSION. CONDITIONS
WILL THEN GRADUALLY IMPROVE ON WEDNESDAY AS THE AFOREMENTIONED LOW
SHIFTS TO THE EAST/SOUTHEAST.

FOR DTW...EXPECT CIGS TO LOWER BELOW 1000 FEET BETWEEN 06Z-08Z WITH
AREAS OF FOG POSSIBLE AFTER 08Z. THIS WILL LINGER THROUGH 14Z OR
SO...BEFORE GRADUAL IMPROVEMENT IN CIGS/VSBYS ENSUES FOR THE REST OF
THE FORECAST PERIOD.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET THROUGH WEDNESDAY
MORNING...WITH MEDIUM CONFIDENCE FOR WEDNESDAY AFTERNOON/EVENING.

&&

.PREV DISCUSSION...ISSUED 354 PM EDT TUE SEP 30 2014

SHORT TERM...TONIGHT

CURRENT MODEL RUNS ARE STILL SHOWING SURFACE RIDGING TO BUILD ACROSS
THE REGION TONIGHT HELPING TO PUT AN END TO ANY LINGERING DRIZZLE
AND RAIN SHOWERS BY EARLY EVENING. ORIGINAL THINKING WAS FOR CLOUDS
TO ALSO DIMINISH SLIGHTLY...HOWEVER...WITH ABUNDANT MOISTURE AROUND
FROM RAIN AND DRIZZLE THROUGHOUT THE DAY...CONFIDENCE IS HIGH IN CLOUD
COVER REMAINING OVERCAST TONIGHT. THIS LOW LEVEL MOISTURE COMBINED
WITH SOME WEAK WARM AIR ADVECTION WILL RESULT IN A HIGHER
PROBABILITY OF LOW STRATUS AND EVEN SOME FOG DEVELOPMENT ESPECIALLY
IN LOW LYING AREAS. ONLY MAJOR CONCERN TO WATCH OUT FOR DURING THE
NEXT FORECAST SHIFT IS THE UNCERTAINTY ABOUT HOW DENSE THE FOG WILL BE
OVERNIGHT. OVERCAST SKIES OVERNIGHT WILL RESULT IN TEMPERATURES TO
ONLY DROP A FEW DEGREES FROM TUESDAYS HIGH TEMPS INTO THE UPPER 40S
AND LOW 50S ACROSS SOUTHEAST MICHIGAN.

LONG TERM...WEDNESDAY THROUGH MONDAY

LONGWAVE PATTERN TO UNDERGO SOME BIG CHANGES THROUGH THE REST OF THE
WEEK LEADING TO A VERY COOL WEEKEND AS A DEEP TROUGH OVERTAKES THE
REGION. THE MIDWEEK TIME FRAME WILL BE THE TRANSITION PERIOD FOR THE
PATTERN AS THE FIRST STRONG WAVE COMES ASHORE THE NW CONUS. THIS
WILL CARVE OUT A TROUGH OVER THE MOUNTAIN WEST WHICH WILL ABSORB A
CUTOFF LOW AS IT MOVES FURTHER EAST. NARROW RIDGE AXIS IN ADVANCE OF
THE TROUGH WILL PASS OVER THE GREAT LAKES WEDNESDAY. MEANWHILE AT
THE SFC...SOUTHERN PERIPHERY OF HIGH PRESSURE OVER ONTARIO/QUEBEC
REMAINS IN CONTROL AT THE SFC BUT WILL DRIFT EAST LOOSENING ITS
GRIP. COOL EASTERLY FLOW WILL BE REPLACED WITH WARMER AND MOISTER
SOUTH/SOUTHWEST FLOW AS THE DEEPENING TROUGH REACHES THE PLAINS
STATES. PATTERN STALLS OVER THE UPPER MISSISSIPPI VALLEY AS A STRONG
WAVE DIVES THROUGH THE TROUGH CHANGING IT FROM A POSITIVE TO NEUTRAL
TILT. AS THE WAVE LIFTS NE OUT OF THE TROUGH...CYCLOGENESIS WILL
ENSUE ALONG A COLD FRONT EXTENDING FROM ONTARIO DOWN INTO OKLAHOMA.
THIS SFC LOW WILL UNDERGO RAPID INTENSIFICATION...DEEPENING FROM
1004MB 18Z THURSDAY DOWN TO 988MB 12Z FRIDAY WHICH IS NEARLY 1
MB/HR. BUT THIS SFC LOW WILL HAVE LITTLE FORWARD PROPAGATION DUE TO
THE UPPER LEVEL TROUGH STALLING.

NOW FOR WHAT THIS MEANS FOR SE MI WEDNESDAY AND THURSDAY. WEDNESDAY
WILL START OFF VERY CLOUDY AS MODEL CONSENSUS KEEPS A VERY MOISTURE
LADEN BL UNDER A STRONG BUT WEAKENING INVERSION. INCREASING HEIGHTS
WITH RIDGE AXIS OVERHEAD WILL PROMOTE SOME WARMING ALONG WITH THE
MORE FAVORABLE WIND DIRECTION. EAST WINDS WILL VEER AROUND SOUTH
LATE IN THE DAY BECOMING SOUTHWEST OVERNIGHT. CURRENT THINKING KEEPS
TEMPS IN THE MID 60S. WILL BE SOME ADDITIONAL POTENTIAL FOR TEMPS TO
JUMP A DEGREE OR TWO WITH WARMER AIR ALOFT BUT MODEL SOUNDINGS SHOW
MIXING DEPTHS STRUGGLING TO TAP INTO THAT AIR. THERE WILL LIKELY BE
A SHARP GRADIENT IN PRECIPITATION ON THURSDAY AS A PREFRONTAL LINE
OF SHOWERS APPROACHES SE MI. THE RIDGE WILL HOLD IT TO THE WEST FOR
MOST OF THE DAY WITH ONLY OUR WESTERN COUNTIES HAVING A CHANCE FOR
ANY SHOWERS. THE STRONGEST OF THE SHORTWAVES THUS FAR WILL SURGE
THROUGH THE TROUGH FORCING THE COLD FRONT THROUGH LOWER MI LATE
THURSDAY NIGHT INTO FRIDAY. GOOD SW FLOW AHEAD OF THE FRONT WILL
RAMP UP WAA WITH TEMPS IN THE MID 70S WHICH WILL DROP OFF
SIGNIFICANTLY POST FRONTAL AS WE EXPERIENCED TODAY FROM THE MOST
RECENT COLD FRONT.

DEEPENING LOW PRESSURE AND ASSOCIATED COLD FRONT WILL CROSS THROUGH
THE STATE ON FRIDAY. THIS FEATURE WILL SPREAD RAIN...BRISK
WINDS...AND A SHARP TEMPERATURE DROP TO THE AREA. EXPECT LOW
STRATUS...DRIZZLE...AND MUCH COOLER TEMPERATURES FOR THE WEEKEND IN
THE POST FRONTAL/UPPER TROUGH PATTERN. TEMPS WILL BE HOVERING AROUND
10 DEGREES BELOW NORMAL FOR THE WEEKEND INTO EARLY NEXT WEEK.

MARINE...

A TIGHT NORTHERLY GRADIENT REMAINS OVER CENTRAL LAKE HURON KEEPING
WIND SPEEDS UP LONGER INTO THE AFTERNOON. THESE WINDS WILL CONTINUE
TO BUILD WAVES UP TO SMALL CRAFT CRITERIA ALONG THE LAKE HURON
SHORELINE OF THE THUMB. SMALL CRAFT ADVISORIES WILL CONTINUE THROUGH
THIS EVENING TO ACCOUNT FOR THAT. WINDS WILL DIMINISH TONIGHT AS
HIGH PRESSURE LESSENS THE GRADIENT OVER THE LAKES BUT THE PERSISTENT
NORTHEAST FLOW WILL KEEP SOME ELEVATED WAVES HEIGHTS INTO THE
OVERNIGHT HOURS. LIGHT WINDS AND LOW WAVES WILL PERSIST WEDNESDAY
INTO THURSDAY. HOWEVER...SOUTHERLY WINDS DEVELOPING AHEAD OF A COLD
FRONT LATE THURSDAY COULD RESULT IN WINDS UP TO 30 KNOTS OVER THE
OPEN WATERS OF LAKE HURON THURSDAY NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO HARBOR BEACH...UNTIL 4 AM WEDNESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....DG
SHORT TERM...RK
LONG TERM....DRK/MM
MARINE.......DRK


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







000
FXUS63 KDTX 010355
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1155 PM EDT TUE SEP 30 2014


.AVIATION...

//DISCUSSION...

VFR CIGS CONTINUE TO SPREAD SOUTHWARD THROUGH THE CWA WITHIN MOIST
CYCLONIC FLOW ON WEST SIDE OF LOW PRESSURE. CIGS/VSBYS ARE EXPECTED
TO EDGE DOWN THROUGH THE NIGHT WITH IFR/LIFR COMMON BY DAWN AS LOW
LEVEL MOISTURE REMAINS TRAPPED UNDER LOWERING INVERSION. CONDITIONS
WILL THEN GRADUALLY IMPROVE ON WEDNESDAY AS THE AFOREMENTIONED LOW
SHIFTS TO THE EAST/SOUTHEAST.

FOR DTW...EXPECT CIGS TO LOWER BELOW 1000 FEET BETWEEN 06Z-08Z WITH
AREAS OF FOG POSSIBLE AFTER 08Z. THIS WILL LINGER THROUGH 14Z OR
SO...BEFORE GRADUAL IMPROVEMENT IN CIGS/VSBYS ENSUES FOR THE REST OF
THE FORECAST PERIOD.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET THROUGH WEDNESDAY
MORNING...WITH MEDIUM CONFIDENCE FOR WEDNESDAY AFTERNOON/EVENING.

&&

.PREV DISCUSSION...ISSUED 354 PM EDT TUE SEP 30 2014

SHORT TERM...TONIGHT

CURRENT MODEL RUNS ARE STILL SHOWING SURFACE RIDGING TO BUILD ACROSS
THE REGION TONIGHT HELPING TO PUT AN END TO ANY LINGERING DRIZZLE
AND RAIN SHOWERS BY EARLY EVENING. ORIGINAL THINKING WAS FOR CLOUDS
TO ALSO DIMINISH SLIGHTLY...HOWEVER...WITH ABUNDANT MOISTURE AROUND
FROM RAIN AND DRIZZLE THROUGHOUT THE DAY...CONFIDENCE IS HIGH IN CLOUD
COVER REMAINING OVERCAST TONIGHT. THIS LOW LEVEL MOISTURE COMBINED
WITH SOME WEAK WARM AIR ADVECTION WILL RESULT IN A HIGHER
PROBABILITY OF LOW STRATUS AND EVEN SOME FOG DEVELOPMENT ESPECIALLY
IN LOW LYING AREAS. ONLY MAJOR CONCERN TO WATCH OUT FOR DURING THE
NEXT FORECAST SHIFT IS THE UNCERTAINTY ABOUT HOW DENSE THE FOG WILL BE
OVERNIGHT. OVERCAST SKIES OVERNIGHT WILL RESULT IN TEMPERATURES TO
ONLY DROP A FEW DEGREES FROM TUESDAYS HIGH TEMPS INTO THE UPPER 40S
AND LOW 50S ACROSS SOUTHEAST MICHIGAN.

LONG TERM...WEDNESDAY THROUGH MONDAY

LONGWAVE PATTERN TO UNDERGO SOME BIG CHANGES THROUGH THE REST OF THE
WEEK LEADING TO A VERY COOL WEEKEND AS A DEEP TROUGH OVERTAKES THE
REGION. THE MIDWEEK TIME FRAME WILL BE THE TRANSITION PERIOD FOR THE
PATTERN AS THE FIRST STRONG WAVE COMES ASHORE THE NW CONUS. THIS
WILL CARVE OUT A TROUGH OVER THE MOUNTAIN WEST WHICH WILL ABSORB A
CUTOFF LOW AS IT MOVES FURTHER EAST. NARROW RIDGE AXIS IN ADVANCE OF
THE TROUGH WILL PASS OVER THE GREAT LAKES WEDNESDAY. MEANWHILE AT
THE SFC...SOUTHERN PERIPHERY OF HIGH PRESSURE OVER ONTARIO/QUEBEC
REMAINS IN CONTROL AT THE SFC BUT WILL DRIFT EAST LOOSENING ITS
GRIP. COOL EASTERLY FLOW WILL BE REPLACED WITH WARMER AND MOISTER
SOUTH/SOUTHWEST FLOW AS THE DEEPENING TROUGH REACHES THE PLAINS
STATES. PATTERN STALLS OVER THE UPPER MISSISSIPPI VALLEY AS A STRONG
WAVE DIVES THROUGH THE TROUGH CHANGING IT FROM A POSITIVE TO NEUTRAL
TILT. AS THE WAVE LIFTS NE OUT OF THE TROUGH...CYCLOGENESIS WILL
ENSUE ALONG A COLD FRONT EXTENDING FROM ONTARIO DOWN INTO OKLAHOMA.
THIS SFC LOW WILL UNDERGO RAPID INTENSIFICATION...DEEPENING FROM
1004MB 18Z THURSDAY DOWN TO 988MB 12Z FRIDAY WHICH IS NEARLY 1
MB/HR. BUT THIS SFC LOW WILL HAVE LITTLE FORWARD PROPAGATION DUE TO
THE UPPER LEVEL TROUGH STALLING.

NOW FOR WHAT THIS MEANS FOR SE MI WEDNESDAY AND THURSDAY. WEDNESDAY
WILL START OFF VERY CLOUDY AS MODEL CONSENSUS KEEPS A VERY MOISTURE
LADEN BL UNDER A STRONG BUT WEAKENING INVERSION. INCREASING HEIGHTS
WITH RIDGE AXIS OVERHEAD WILL PROMOTE SOME WARMING ALONG WITH THE
MORE FAVORABLE WIND DIRECTION. EAST WINDS WILL VEER AROUND SOUTH
LATE IN THE DAY BECOMING SOUTHWEST OVERNIGHT. CURRENT THINKING KEEPS
TEMPS IN THE MID 60S. WILL BE SOME ADDITIONAL POTENTIAL FOR TEMPS TO
JUMP A DEGREE OR TWO WITH WARMER AIR ALOFT BUT MODEL SOUNDINGS SHOW
MIXING DEPTHS STRUGGLING TO TAP INTO THAT AIR. THERE WILL LIKELY BE
A SHARP GRADIENT IN PRECIPITATION ON THURSDAY AS A PREFRONTAL LINE
OF SHOWERS APPROACHES SE MI. THE RIDGE WILL HOLD IT TO THE WEST FOR
MOST OF THE DAY WITH ONLY OUR WESTERN COUNTIES HAVING A CHANCE FOR
ANY SHOWERS. THE STRONGEST OF THE SHORTWAVES THUS FAR WILL SURGE
THROUGH THE TROUGH FORCING THE COLD FRONT THROUGH LOWER MI LATE
THURSDAY NIGHT INTO FRIDAY. GOOD SW FLOW AHEAD OF THE FRONT WILL
RAMP UP WAA WITH TEMPS IN THE MID 70S WHICH WILL DROP OFF
SIGNIFICANTLY POST FRONTAL AS WE EXPERIENCED TODAY FROM THE MOST
RECENT COLD FRONT.

DEEPENING LOW PRESSURE AND ASSOCIATED COLD FRONT WILL CROSS THROUGH
THE STATE ON FRIDAY. THIS FEATURE WILL SPREAD RAIN...BRISK
WINDS...AND A SHARP TEMPERATURE DROP TO THE AREA. EXPECT LOW
STRATUS...DRIZZLE...AND MUCH COOLER TEMPERATURES FOR THE WEEKEND IN
THE POST FRONTAL/UPPER TROUGH PATTERN. TEMPS WILL BE HOVERING AROUND
10 DEGREES BELOW NORMAL FOR THE WEEKEND INTO EARLY NEXT WEEK.

MARINE...

A TIGHT NORTHERLY GRADIENT REMAINS OVER CENTRAL LAKE HURON KEEPING
WIND SPEEDS UP LONGER INTO THE AFTERNOON. THESE WINDS WILL CONTINUE
TO BUILD WAVES UP TO SMALL CRAFT CRITERIA ALONG THE LAKE HURON
SHORELINE OF THE THUMB. SMALL CRAFT ADVISORIES WILL CONTINUE THROUGH
THIS EVENING TO ACCOUNT FOR THAT. WINDS WILL DIMINISH TONIGHT AS
HIGH PRESSURE LESSENS THE GRADIENT OVER THE LAKES BUT THE PERSISTENT
NORTHEAST FLOW WILL KEEP SOME ELEVATED WAVES HEIGHTS INTO THE
OVERNIGHT HOURS. LIGHT WINDS AND LOW WAVES WILL PERSIST WEDNESDAY
INTO THURSDAY. HOWEVER...SOUTHERLY WINDS DEVELOPING AHEAD OF A COLD
FRONT LATE THURSDAY COULD RESULT IN WINDS UP TO 30 KNOTS OVER THE
OPEN WATERS OF LAKE HURON THURSDAY NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO HARBOR BEACH...UNTIL 4 AM WEDNESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....DG
SHORT TERM...RK
LONG TERM....DRK/MM
MARINE.......DRK


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








000
FXUS63 KDTX 301954
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
354 PM EDT TUE SEP 30 2014

.SHORT TERM...TONIGHT

CURRENT MODEL RUNS ARE STILL SHOWING SURFACE RIDGING TO BUILD ACROSS
THE REGION TONIGHT HELPING TO PUT AN END TO ANY LINGERING DRIZZLE
AND RAIN SHOWERS BY EARLY EVENING. ORIGINAL THINKING WAS FOR CLOUDS
TO ALSO DIMINISH SLIGHTLY...HOWEVER...WITH ABUNDANT MOISTURE AROUND
FROM RAIN AND DRIZZLE THROUGHOUT THE DAY...CONFIDENCE IS HIGH IN CLOUD
COVER REMAINING OVERCAST TONIGHT. THIS LOW LEVEL MOISTURE COMBINED
WITH SOME WEAK WARM AIR ADVECTION WILL RESULT IN A HIGHER
PROBABILITY OF LOW STRATUS AND EVEN SOME FOG DEVELOPMENT ESPECIALLY
IN LOW LYING AREAS. ONLY MAJOR CONCERN TO WATCH OUT FOR DURING THE
NEXT FORECAST SHIFT IS THE UNCERTAINTY ABOUT HOW DENSE THE FOG WILL BE
OVERNIGHT. OVERCAST SKIES OVERNIGHT WILL RESULT IN TEMPERATURES TO
ONLY DROP A FEW DEGREES FROM TUESDAYS HIGH TEMPS INTO THE UPPER 40S
AND LOW 50S ACROSS SOUTHEAST MICHIGAN.

&&

.LONG TERM...WEDNESDAY THROUGH MONDAY

LONGWAVE PATTERN TO UNDERGO SOME BIG CHANGES THROUGH THE REST OF THE
WEEK LEADING TO A VERY COOL WEEKEND AS A DEEP TROUGH OVERTAKES THE
REGION. THE MIDWEEK TIME FRAME WILL BE THE TRANSITION PERIOD FOR THE
PATTERN AS THE FIRST STRONG WAVE COMES ASHORE THE NW CONUS. THIS
WILL CARVE OUT A TROUGH OVER THE MOUNTAIN WEST WHICH WILL ABSORB A
CUTOFF LOW AS IT MOVES FURTHER EAST. NARROW RIDGE AXIS IN ADVANCE OF
THE TROUGH WILL PASS OVER THE GREAT LAKES WEDNESDAY. MEANWHILE AT
THE SFC...SOUTHERN PERIPHERY OF HIGH PRESSURE OVER ONTARIO/QUEBEC
REMAINS IN CONTROL AT THE SFC BUT WILL DRIFT EAST LOOSENING ITS
GRIP. COOL EASTERLY FLOW WILL BE REPLACED WITH WARMER AND MOISTER
SOUTH/SOUTHWEST FLOW AS THE DEEPENING TROUGH REACHES THE PLAINS
STATES. PATTERN STALLS OVER THE UPPER MISSISSIPPI VALLEY AS A STRONG
WAVE DIVES THROUGH THE TROUGH CHANGING IT FROM A POSITIVE TO NEUTRAL
TILT. AS THE WAVE LIFTS NE OUT OF THE TROUGH...CYCLOGENESIS WILL
ENSUE ALONG A COLD FRONT EXTENDING FROM ONTARIO DOWN INTO OKLAHOMA.
THIS SFC LOW WILL UNDERGO RAPID INTENSIFICATION...DEEPENING FROM
1004MB 18Z THURSDAY DOWN TO 988MB 12Z FRIDAY WHICH IS NEARLY 1
MB/HR. BUT THIS SFC LOW WILL HAVE LITTLE FORWARD PROPAGATION DUE TO
THE UPPER LEVEL TROUGH STALLING.

NOW FOR WHAT THIS MEANS FOR SE MI WEDNESDAY AND THURSDAY. WEDNESDAY
WILL START OFF VERY CLOUDY AS MODEL CONSENSUS KEEPS A VERY MOISTURE
LADEN BL UNDER A STRONG BUT WEAKENING INVERSION. INCREASING HEIGHTS
WITH RIDGE AXIS OVERHEAD WILL PROMOTE SOME WARMING ALONG WITH THE
MORE FAVORABLE WIND DIRECTION. EAST WINDS WILL VEER AROUND SOUTH
LATE IN THE DAY BECOMING SOUTHWEST OVERNIGHT. CURRENT THINKING KEEPS
TEMPS IN THE MID 60S. WILL BE SOME ADDITIONAL POTENTIAL FOR TEMPS TO
JUMP A DEGREE OR TWO WITH WARMER AIR ALOFT BUT MODEL SOUNDINGS SHOW
MIXING DEPTHS STRUGGLING TO TAP INTO THAT AIR. THERE WILL LIKELY BE
A SHARP GRADIENT IN PRECIPITATION ON THURSDAY AS A PREFRONTAL LINE
OF SHOWERS APPROACHES SE MI. THE RIDGE WILL HOLD IT TO THE WEST FOR
MOST OF THE DAY WITH ONLY OUR WESTERN COUNTIES HAVING A CHANCE FOR
ANY SHOWERS. THE STRONGEST OF THE SHORTWAVES THUS FAR WILL SURGE
THROUGH THE TROUGH FORCING THE COLD FRONT THROUGH LOWER MI LATE
THURSDAY NIGHT INTO FRIDAY. GOOD SW FLOW AHEAD OF THE FRONT WILL
RAMP UP WAA WITH TEMPS IN THE MID 70S WHICH WILL DROP OFF
SIGNIFICANTLY POST FRONTAL AS WE EXPERIENCED TODAY FROM THE MOST
RECENT COLD FRONT.

DEEPENING LOW PRESSURE AND ASSOCIATED COLD FRONT WILL CROSS THROUGH
THE STATE ON FRIDAY. THIS FEATURE WILL SPREAD RAIN...BRISK
WINDS...AND A SHARP TEMPERATURE DROP TO THE AREA. EXPECT LOW
STRATUS...DRIZZLE...AND MUCH COOLER TEMPERATURES FOR THE WEEKEND IN
THE POST FRONTAL/UPPER TROUGH PATTERN. TEMPS WILL BE HOVERING AROUND
10 DEGREES BELOW NORMAL FOR THE WEEKEND INTO EARLY NEXT WEEK.

&&

.MARINE...

A TIGHT NORTHERLY GRADIENT REMAINS OVER CENTRAL LAKE HURON KEEPING
WIND SPEEDS UP LONGER INTO THE AFTERNOON. THESE WINDS WILL CONTINUE
TO BUILD WAVES UP TO SMALL CRAFT CRITERIA ALONG THE LAKE HURON
SHORELINE OF THE THUMB. SMALL CRAFT ADVISORIES WILL CONTINUE THROUGH
THIS EVENING TO ACCOUNT FOR THAT. WINDS WILL DIMINISH TONIGHT AS
HIGH PRESSURE LESSENS THE GRADIENT OVER THE LAKES BUT THE PERSISTENT
NORTHEAST FLOW WILL KEEP SOME ELEVATED WAVES HEIGHTS INTO THE
OVERNIGHT HOURS. LIGHT WINDS AND LOW WAVES WILL PERSIST WEDNESDAY
INTO THURSDAY. HOWEVER...SOUTHERLY WINDS DEVELOPING AHEAD OF A COLD
FRONT LATE THURSDAY COULD RESULT IN WINDS UP TO 30 KNOTS OVER THE
OPEN WATERS OF LAKE HURON THURSDAY NIGHT.

&&

.AVIATION...ISSUED 115 PM EDT TUE SEP 30 2014

//DISCUSSION...

FOR THE MOST PART DRIZZLE IS COMING TO AN END ACROSS SOUTHEAST
MICHIGAN. HOWEVER...RECENT RADAR IMAGERY STILL IS SHOWING SOME
SPOTTY DRIZZLE TRYING TO FORCE INTO THE REGION. THEREFORE...HAVE
KEPT A TEMPO OF DRIZZLE IN THE FORECAST UNTIL 22Z. CEILINGS WILL
REMAIN OVERCAST AND BELOW 2000 FEET THROUGH THE WEDNESDAY
AFTERNOON AS LOW LEVEL MOISTURE CONTINUES TO FILTER ACROSS THE TAF
SITES.

FOR DTW...LINGERING DRIZZLE WILL BE POSSIBLE AT METRO THIS
AFTERNOON. CURRENTLY EXPECTING THE CHANCE FOR DRIZZLE DEVELOPMENT TO
END BY 22Z...HOWEVER LOW CLOUDS /BELOW 2000 FEET/ WILL STICK AROUND
THROUGH WEDNESDAY MORNING.

//DTW THRESHOLD THREATS...

* HIGH PROBABILITY THAT CEILINGS WILL REMAIN BELOW 5000 FT THROUGH WEDNESDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO HARBOR BEACH...UNTIL 10 PM TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...RK
LONG TERM....DRK/MM
MARINE.......DRK
AVIATION.....RK


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







000
FXUS63 KDTX 301954
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
354 PM EDT TUE SEP 30 2014

.SHORT TERM...TONIGHT

CURRENT MODEL RUNS ARE STILL SHOWING SURFACE RIDGING TO BUILD ACROSS
THE REGION TONIGHT HELPING TO PUT AN END TO ANY LINGERING DRIZZLE
AND RAIN SHOWERS BY EARLY EVENING. ORIGINAL THINKING WAS FOR CLOUDS
TO ALSO DIMINISH SLIGHTLY...HOWEVER...WITH ABUNDANT MOISTURE AROUND
FROM RAIN AND DRIZZLE THROUGHOUT THE DAY...CONFIDENCE IS HIGH IN CLOUD
COVER REMAINING OVERCAST TONIGHT. THIS LOW LEVEL MOISTURE COMBINED
WITH SOME WEAK WARM AIR ADVECTION WILL RESULT IN A HIGHER
PROBABILITY OF LOW STRATUS AND EVEN SOME FOG DEVELOPMENT ESPECIALLY
IN LOW LYING AREAS. ONLY MAJOR CONCERN TO WATCH OUT FOR DURING THE
NEXT FORECAST SHIFT IS THE UNCERTAINTY ABOUT HOW DENSE THE FOG WILL BE
OVERNIGHT. OVERCAST SKIES OVERNIGHT WILL RESULT IN TEMPERATURES TO
ONLY DROP A FEW DEGREES FROM TUESDAYS HIGH TEMPS INTO THE UPPER 40S
AND LOW 50S ACROSS SOUTHEAST MICHIGAN.

&&

.LONG TERM...WEDNESDAY THROUGH MONDAY

LONGWAVE PATTERN TO UNDERGO SOME BIG CHANGES THROUGH THE REST OF THE
WEEK LEADING TO A VERY COOL WEEKEND AS A DEEP TROUGH OVERTAKES THE
REGION. THE MIDWEEK TIME FRAME WILL BE THE TRANSITION PERIOD FOR THE
PATTERN AS THE FIRST STRONG WAVE COMES ASHORE THE NW CONUS. THIS
WILL CARVE OUT A TROUGH OVER THE MOUNTAIN WEST WHICH WILL ABSORB A
CUTOFF LOW AS IT MOVES FURTHER EAST. NARROW RIDGE AXIS IN ADVANCE OF
THE TROUGH WILL PASS OVER THE GREAT LAKES WEDNESDAY. MEANWHILE AT
THE SFC...SOUTHERN PERIPHERY OF HIGH PRESSURE OVER ONTARIO/QUEBEC
REMAINS IN CONTROL AT THE SFC BUT WILL DRIFT EAST LOOSENING ITS
GRIP. COOL EASTERLY FLOW WILL BE REPLACED WITH WARMER AND MOISTER
SOUTH/SOUTHWEST FLOW AS THE DEEPENING TROUGH REACHES THE PLAINS
STATES. PATTERN STALLS OVER THE UPPER MISSISSIPPI VALLEY AS A STRONG
WAVE DIVES THROUGH THE TROUGH CHANGING IT FROM A POSITIVE TO NEUTRAL
TILT. AS THE WAVE LIFTS NE OUT OF THE TROUGH...CYCLOGENESIS WILL
ENSUE ALONG A COLD FRONT EXTENDING FROM ONTARIO DOWN INTO OKLAHOMA.
THIS SFC LOW WILL UNDERGO RAPID INTENSIFICATION...DEEPENING FROM
1004MB 18Z THURSDAY DOWN TO 988MB 12Z FRIDAY WHICH IS NEARLY 1
MB/HR. BUT THIS SFC LOW WILL HAVE LITTLE FORWARD PROPAGATION DUE TO
THE UPPER LEVEL TROUGH STALLING.

NOW FOR WHAT THIS MEANS FOR SE MI WEDNESDAY AND THURSDAY. WEDNESDAY
WILL START OFF VERY CLOUDY AS MODEL CONSENSUS KEEPS A VERY MOISTURE
LADEN BL UNDER A STRONG BUT WEAKENING INVERSION. INCREASING HEIGHTS
WITH RIDGE AXIS OVERHEAD WILL PROMOTE SOME WARMING ALONG WITH THE
MORE FAVORABLE WIND DIRECTION. EAST WINDS WILL VEER AROUND SOUTH
LATE IN THE DAY BECOMING SOUTHWEST OVERNIGHT. CURRENT THINKING KEEPS
TEMPS IN THE MID 60S. WILL BE SOME ADDITIONAL POTENTIAL FOR TEMPS TO
JUMP A DEGREE OR TWO WITH WARMER AIR ALOFT BUT MODEL SOUNDINGS SHOW
MIXING DEPTHS STRUGGLING TO TAP INTO THAT AIR. THERE WILL LIKELY BE
A SHARP GRADIENT IN PRECIPITATION ON THURSDAY AS A PREFRONTAL LINE
OF SHOWERS APPROACHES SE MI. THE RIDGE WILL HOLD IT TO THE WEST FOR
MOST OF THE DAY WITH ONLY OUR WESTERN COUNTIES HAVING A CHANCE FOR
ANY SHOWERS. THE STRONGEST OF THE SHORTWAVES THUS FAR WILL SURGE
THROUGH THE TROUGH FORCING THE COLD FRONT THROUGH LOWER MI LATE
THURSDAY NIGHT INTO FRIDAY. GOOD SW FLOW AHEAD OF THE FRONT WILL
RAMP UP WAA WITH TEMPS IN THE MID 70S WHICH WILL DROP OFF
SIGNIFICANTLY POST FRONTAL AS WE EXPERIENCED TODAY FROM THE MOST
RECENT COLD FRONT.

DEEPENING LOW PRESSURE AND ASSOCIATED COLD FRONT WILL CROSS THROUGH
THE STATE ON FRIDAY. THIS FEATURE WILL SPREAD RAIN...BRISK
WINDS...AND A SHARP TEMPERATURE DROP TO THE AREA. EXPECT LOW
STRATUS...DRIZZLE...AND MUCH COOLER TEMPERATURES FOR THE WEEKEND IN
THE POST FRONTAL/UPPER TROUGH PATTERN. TEMPS WILL BE HOVERING AROUND
10 DEGREES BELOW NORMAL FOR THE WEEKEND INTO EARLY NEXT WEEK.

&&

.MARINE...

A TIGHT NORTHERLY GRADIENT REMAINS OVER CENTRAL LAKE HURON KEEPING
WIND SPEEDS UP LONGER INTO THE AFTERNOON. THESE WINDS WILL CONTINUE
TO BUILD WAVES UP TO SMALL CRAFT CRITERIA ALONG THE LAKE HURON
SHORELINE OF THE THUMB. SMALL CRAFT ADVISORIES WILL CONTINUE THROUGH
THIS EVENING TO ACCOUNT FOR THAT. WINDS WILL DIMINISH TONIGHT AS
HIGH PRESSURE LESSENS THE GRADIENT OVER THE LAKES BUT THE PERSISTENT
NORTHEAST FLOW WILL KEEP SOME ELEVATED WAVES HEIGHTS INTO THE
OVERNIGHT HOURS. LIGHT WINDS AND LOW WAVES WILL PERSIST WEDNESDAY
INTO THURSDAY. HOWEVER...SOUTHERLY WINDS DEVELOPING AHEAD OF A COLD
FRONT LATE THURSDAY COULD RESULT IN WINDS UP TO 30 KNOTS OVER THE
OPEN WATERS OF LAKE HURON THURSDAY NIGHT.

&&

.AVIATION...ISSUED 115 PM EDT TUE SEP 30 2014

//DISCUSSION...

FOR THE MOST PART DRIZZLE IS COMING TO AN END ACROSS SOUTHEAST
MICHIGAN. HOWEVER...RECENT RADAR IMAGERY STILL IS SHOWING SOME
SPOTTY DRIZZLE TRYING TO FORCE INTO THE REGION. THEREFORE...HAVE
KEPT A TEMPO OF DRIZZLE IN THE FORECAST UNTIL 22Z. CEILINGS WILL
REMAIN OVERCAST AND BELOW 2000 FEET THROUGH THE WEDNESDAY
AFTERNOON AS LOW LEVEL MOISTURE CONTINUES TO FILTER ACROSS THE TAF
SITES.

FOR DTW...LINGERING DRIZZLE WILL BE POSSIBLE AT METRO THIS
AFTERNOON. CURRENTLY EXPECTING THE CHANCE FOR DRIZZLE DEVELOPMENT TO
END BY 22Z...HOWEVER LOW CLOUDS /BELOW 2000 FEET/ WILL STICK AROUND
THROUGH WEDNESDAY MORNING.

//DTW THRESHOLD THREATS...

* HIGH PROBABILITY THAT CEILINGS WILL REMAIN BELOW 5000 FT THROUGH WEDNESDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO HARBOR BEACH...UNTIL 10 PM TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...RK
LONG TERM....DRK/MM
MARINE.......DRK
AVIATION.....RK


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








000
FXUS63 KDTX 301715
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
115 PM EDT TUE SEP 30 2014


.AVIATION...

//DISCUSSION...

FOR THE MOST PART DRIZZLE IS COMING TO AN END ACROSS SOUTHEAST
MICHIGAN. HOWEVER...RECENT RADAR IMAGERY STILL IS SHOWING SOME
SPOTTY DRIZZLE TRYING TO FORCE INTO THE REGION. THEREFORE...HAVE
KEPT A TEMPO OF DRIZZLE IN THE FORECAST UNTIL 22Z. CEILINGS WILL
REMAIN OVERCAST AND BELOW 2000 FEET THROUGH THE WEDNESDAY
AFTERNOON AS LOW LEVEL MOISTURE CONTINUES TO FILTER ACROSS THE TAF
SITES.

FOR DTW...LINGERING DRIZZLE WILL BE POSSIBLE AT METRO THIS
AFTERNOON. CURRENTLY EXPECTING THE CHANCE FOR DRIZZLE DEVELOPMENT TO
END BY 22Z...HOWEVER LOW CLOUDS /BELOW 2000 FEET/ WILL STICK AROUND
THROUGH WEDNESDAY MORNING.

//DTW THRESHOLD THREATS...

* HIGH PROBABILITY THAT CEILINGS WILL REMAIN BELOW 5000 FT THROUGH WEDNESDAY.

&&

.PREV DISCUSSION...ISSUED 335 AM EDT TUE SEP 30 2014

SHORT TERM...TODAY AND TONIGHT

LOW LEVEL COLD AIR ADVECTION WILL PREVAIL THROUGH THE MORNING BEHIND
THE SURFACE COLD FRONT WHICH EXITED THE FORECAST AREA SHORTLY AFTER
06Z. LINGERING POST FRONTAL SHOWERS WILL EXIT TO THE SOUTHEAST OF
THE STATE BEFORE DAYBREAK. THE SHOWERS OVERNIGHT DEVELOPED WITHIN A
RIBBON OF STRONG LARGE SCALE ASCENT ALONG THE LEAD EDGE OF AN
AMPLIFYING UPPER WAVE. RECENT WATER VAPOR IMAGERY ALREADY SHOWS THE
EVOLUTION OF THIS SYSTEM INTO A CLOSED MID LEVEL LOW...WHICH IS
FORECAST TO ROTATE ACROSS THE THUMB THIS MORNING AND INTO NE OHIO
THIS AFTERNOON. THE ASSOCIATED SFC LOW...NOW LOCATED OVER SRN
ONTARIO...WILL IN TURN TRACK INTO WRN PA/WV THIS AFTERNOON.

RESIDUAL LOW LEVEL MOISTURE AND A DEEPENING POST FRONTAL INVERSION
HAS LED TO A STRATUS DECK NOW EXTENDING ALL THE WAY TO SRN LAKE
SUPERIOR. THIS INVERSION WILL ONLY DEEPEN DURING THE COURSE OF THE
MORNING AS 925MB TEMPS FALL THROUGH THE SINGLE DIGITS. LOW CLOUDS
WILL THUS REMAIN IN PLACE INTO AT LEAST LATE EVENING. THIS WILL
LIMIT ANY DIURNAL RECOVERY AND HOLD DAYTIME TEMPS IN THE 50S. THE
EVOLVING COMPACT MID LEVEL LOW WILL SUPPORT THE DEVELOPMENT OF AN
ENHANCED REGION OF MID LEVEL DEFORMATION /TROWEL FEATURE/ TARGETING
NRN/CNTL LAKE HURON AND NE LOWER MI. MODEL SOLUTIONS THEN INDICATE
THIS FEATURE FALLING APART AS IT ADVANCES INTO SE MI TONIGHT AS THE
UPPER LOW WEAKENS AND QUICKLY ADVANCES EAST. SO THE BETTER FORCING
WILL REMAIN NORTH OF THE AREA TODAY. HOWEVER...MODEL SOUNDINGS ARE
VERY SUPPORTIVE OF DRIZZLE TODAY /RADAR AND SFC OBS OVER NRN LOWER
MI OVERNIGHT HAVE ALSO BEEN SHOWING A LOT OF DRIZZLE/. THIS IS DUE
TO A MOIST BOUNDARY LAYER...LOW CLOUD BASES...SUBSTANTIAL DRY AIR
ABOVE THE INVERSION...AND GOOD DIRECTIONAL SHEAR NEAR THE TOP OF THE
MOIST LAYER. THE DRIZZLE IS EXPECTED TO BE QUITE WIDESPREAD OVER
MUCH OF THE THUMB TODAY AS N-NW FLOW OVER LAKE HURON ADDS A LITTLE
BETTER MOISTURE TO THE BOUNDARY LAYER AND ENHANCES CONVERGENCE ALONG
THE SHORELINE.

SFC RIDGING WILL BUILD ACROSS LOWER MI TONIGHT...WHILE ENHANCED
THERMAL TROUGHING WILL RESIDE OVER LAKE HURON. THE FLOW ABOVE THE
BOUNDARY LAYER WILL TURN TOWARD THE EAST WHICH WILL ACTUALLY SUPPORT
SOME LOW LEVEL WARM AIR ADVECTION. THIS WILL WEAKEN /POSSIBLY EVEN
ERODE/ THE LOW LEVEL INVERSION AND MAY SUPPORT SOME CLEARING ACROSS
AT LEAST THE WRN PORTIONS OF THE AREA AS THE SFC HIGH BUILDS IN FROM
THE NORTH. CLEARING POTENTIAL STILL HOWEVER CARRIES A LOW CONFIDENCE
AS THE EASTERLY FLOW WILL ALSO ADVECT SOME HIGHER MOISTURE IN FROM
THE EAST. SO FOG AND/OR ADDITIONAL STRATUS DEVELOPMENT SEEM
POSSIBLE. THE POTENTIAL CLOUD COVER AND LOW LEVEL MOISTURE ADVECTION
WILL WARRANT A LIMITED DROP IN TEMPS TONIGHT /LOWS FROM THE MID 40S
TO LOW 50S/.

LONG TERM...

CONFIDENCE IS NOT VERY HIGH IN LOW CLOUDS SCOURING OUT COMPLETELY
ON WEDNESDAY...AS NAM/GFS/GEM/EURO ALL SUGGESTING SOME 925-850 MB
RESIDUAL MOISTURE UNDERNEATH THE MODEST UPPER LEVEL
RIDGE...ESPECIALLY BACK ACROSS THE THUMB REGION. WITH JUST PARTIAL
INSOLATION EXPECTED...LOOKING AT MAXES COMING UP JUST SHORT OF 70
DEGREES. WE SHOULD HOWEVER HAVE NO PROBLEM CLIMBING INTO THE 70S ON
THURSDAY AHEAD OF A COLD FRONT...WITH GOOD WARM ADVECTION ALLOWING
925 MB TEMPS TO CLIMB INTO THE UPPER TEENS TO LOWER 20S PER 00Z
EURO. HOWEVER...WITH INCREASING AND THICKENING CLOUDS...BACKED
SOUTHEAST FLOW AT THE SURFACE...BOUNDARY LAYER MIXING WILL PROBABLY
COME UP JUST SHORT OF 925 MB AND WILL HOLD MAXES IN THE MID TO
UPPER 70S.

WITH A VERY GOOD MOISTURE FEED...PW VALUES IN EXCESS OF 1.5
INCHES...COUPLED WITH GOOD HEIGHT FALLS AND MODEST INSTABILITY
THURSDAY NIGHT...RAIN SHOWERS CAN BE EXPECTED...WITH EVEN COLDER AIR
ON TAP FOR THE WEEKEND AS UPPER LEVEL ENERGY OVER THE GULF OF ALASKA
AND OFF THE COAST OF BRITISH COLUMBIA/PACIFIC NORTHWEST CONSOLIDATE
OVER THE GREAT LAKES REGION...LEADING TO DEEP 500 MB LOW. IN
FACT...THE LONGWAVE UPPER LEVEL TROUGH AXIS WILL BE ATTEMPTING TO GO
SLIGHTLY NEGATIVE FRIDAY MORNING...WHICH IS YIELDING A SLOWER
FRONTAL PASSAGE COMPARED TO LAST NIGHT...AND IT APPEARS SHOWERS WILL
LIKELY LINGER INTO FRIDAY. COLD CYCLONIC FLOW AND 850 MB TEMPS
FALLING BELOW ZERO OVER THE WEEKEND WILL LIKELY TRANSLATE TO AT
LEAST SCATTERED LAKE ENHANCED SHOWERS AND MOSTLY CLOUDY SKIES...WITH
FORECASTED 850 MB TEMPS OF -2 C YIELDING HIGHS ONLY IN THE LOW TO
MID 50S ON SATURDAY.

MARINE...

A STRONG COLD FRONT WILL CLEAR THE CENTRAL GREAT LAKES THIS
MORNING...WITH RELATIVELY SHORT LIVED WINDS OF 15 TO 20 KNOTS WITH
GUSTS TO 25 KNOTS ACROSS CENTRAL AND SOUTHERN SECTIONS OF LAKE
HURON.  THIS WILL PROMPT AN INCREASE IN WAVE HEIGHTS...WITH HEIGHTS
TOPPING OUT SLIGHTLY ABOVE 4 FEET OVER MUCH OF SOUTHERN LAKE
HURON...AND THE PREVIOUS SMALL CRAFT ADVISORIES WILL CONTINUE
THROUGH THE DAY. WINDS WILL DIMINISH BY TONIGHT AS HIGH PRESSURE
BUILDS BACK INTO THE REGION...BUT THE NORTHEAST DIRECTION WILL
MAINTAIN SOME MODEST WAVES OVER THE NEARSHORE WATERS. LIGHT WINDS
AND LOW WAVES WILL PERSIST WEDNESDAY INTO THURSDAY.
HOWEVER...SOUTHERLY WINDS DEVELOPING AHEAD OF A COLD FRONT LATE
THURSDAY COULD RESULT IN WINDS UP TO 30 KNOTS OVER THE OPEN WATERS
OF LAKE HURON THURSDAY NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...UNTIL 6 PM TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....RK
SHORT TERM...SC
LONG TERM....SF
MARINE.......SF


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









000
FXUS63 KDTX 301102
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
702 AM EDT TUE SEP 30 2014


.AVIATION...

//DISCUSSION...

POST FRONTAL STRATUS WILL REMAIN IN PLACE THROUGH THE DAY DUE TO
LINGERING LOW LEVEL MOISTURE UNDER A DEEP INVERSION. CEILINGS HAVE
RANGED FROM IFR TO LOW END MVFR. SUBTLE LOW LEVEL DRY AIR ADVECTION
FROM THE NORTH THIS MORNING WILL TREND CEILINGS TOWARD LOW END MVFR.
HOWEVER...CONFIDENCE ON THE TIMING OF THIS IS RATHER LOW.

FOR DTW...THERE MAY BE A FEW AREAS OF LINGERING DRIZZLE AROUND METRO
THIS MORNING. GIVEN THE DOWNSLOPE COMPONENT TO THE WIND...THE
EXPECTATION IS THAT MOST OF THE DRIZZLE TODAY WILL REMAIN AROUND PTK
AND POINTS NORTH.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FT TODAY AND TONIGHT.

* LOW CONFIDENCE IN VISIBILITIES BELOW 1/2SM AND/OR CEILINGS BELOW
200 FT LATE TONIGHT THROUGH DAYBREAK WED MORNING.

&&

.PREV DISCUSSION...ISSUED 335 AM EDT TUE SEP 30 2014

SHORT TERM...TODAY AND TONIGHT

LOW LEVEL COLD AIR ADVECTION WILL PREVAIL THROUGH THE MORNING BEHIND
THE SURFACE COLD FRONT WHICH EXITED THE FORECAST AREA SHORTLY AFTER
06Z. LINGERING POST FRONTAL SHOWERS WILL EXIT TO THE SOUTHEAST OF
THE STATE BEFORE DAYBREAK. THE SHOWERS OVERNIGHT DEVELOPED WITHIN A
RIBBON OF STRONG LARGE SCALE ASCENT ALONG THE LEAD EDGE OF AN
AMPLIFYING UPPER WAVE. RECENT WATER VAPOR IMAGERY ALREADY SHOWS THE
EVOLUTION OF THIS SYSTEM INTO A CLOSED MID LEVEL LOW...WHICH IS
FORECAST TO ROTATE ACROSS THE THUMB THIS MORNING AND INTO NE OHIO
THIS AFTERNOON. THE ASSOCIATED SFC LOW...NOW LOCATED OVER SRN
ONTARIO...WILL IN TURN TRACK INTO WRN PA/WV THIS AFTERNOON.

RESIDUAL LOW LEVEL MOISTURE AND A DEEPENING POST FRONTAL INVERSION
HAS LED TO A STRATUS DECK NOW EXTENDING ALL THE WAY TO SRN LAKE
SUPERIOR. THIS INVERSION WILL ONLY DEEPEN DURING THE COURSE OF THE
MORNING AS 925MB TEMPS FALL THROUGH THE SINGLE DIGITS. LOW CLOUDS
WILL THUS REMAIN IN PLACE INTO AT LEAST LATE EVENING. THIS WILL
LIMIT ANY DIURNAL RECOVERY AND HOLD DAYTIME TEMPS IN THE 50S. THE
EVOLVING COMPACT MID LEVEL LOW WILL SUPPORT THE DEVELOPMENT OF AN
ENHANCED REGION OF MID LEVEL DEFORMATION /TROWEL FEATURE/ TARGETING
NRN/CNTL LAKE HURON AND NE LOWER MI. MODEL SOLUTIONS THEN INDICATE
THIS FEATURE FALLING APART AS IT ADVANCES INTO SE MI TONIGHT AS THE
UPPER LOW WEAKENS AND QUICKLY ADVANCES EAST. SO THE BETTER FORCING
WILL REMAIN NORTH OF THE AREA TODAY. HOWEVER...MODEL SOUNDINGS ARE
VERY SUPPORTIVE OF DRIZZLE TODAY /RADAR AND SFC OBS OVER NRN LOWER
MI OVERNIGHT HAVE ALSO BEEN SHOWING A LOT OF DRIZZLE/. THIS IS DUE
TO A MOIST BOUNDARY LAYER...LOW CLOUD BASES...SUBSTANTIAL DRY AIR
ABOVE THE INVERSION...AND GOOD DIRECTIONAL SHEAR NEAR THE TOP OF THE
MOIST LAYER. THE DRIZZLE IS EXPECTED TO BE QUITE WIDESPREAD OVER
MUCH OF THE THUMB TODAY AS N-NW FLOW OVER LAKE HURON ADDS A LITTLE
BETTER MOISTURE TO THE BOUNDARY LAYER AND ENHANCES CONVERGENCE ALONG
THE SHORELINE.

SFC RIDGING WILL BUILD ACROSS LOWER MI TONIGHT...WHILE ENHANCED
THERMAL TROUGHING WILL RESIDE OVER LAKE HURON. THE FLOW ABOVE THE
BOUNDARY LAYER WILL TURN TOWARD THE EAST WHICH WILL ACTUALLY SUPPORT
SOME LOW LEVEL WARM AIR ADVECTION. THIS WILL WEAKEN /POSSIBLY EVEN
ERODE/ THE LOW LEVEL INVERSION AND MAY SUPPORT SOME CLEARING ACROSS
AT LEAST THE WRN PORTIONS OF THE AREA AS THE SFC HIGH BUILDS IN FROM
THE NORTH. CLEARING POTENTIAL STILL HOWEVER CARRIES A LOW CONFIDENCE
AS THE EASTERLY FLOW WILL ALSO ADVECT SOME HIGHER MOISTURE IN FROM
THE EAST. SO FOG AND/OR ADDITIONAL STRATUS DEVELOPMENT SEEM
POSSIBLE. THE POTENTIAL CLOUD COVER AND LOW LEVEL MOISTURE ADVECTION
WILL WARRANT A LIMITED DROP IN TEMPS TONIGHT /LOWS FROM THE MID 40S
TO LOW 50S/.

LONG TERM...

CONFIDENCE IS NOT VERY HIGH IN LOW CLOUDS SCOURING OUT COMPLETELY
ON WEDNESDAY...AS NAM/GFS/GEM/EURO ALL SUGGESTING SOME 925-850 MB
RESIDUAL MOISTURE UNDERNEATH THE MODEST UPPER LEVEL
RIDGE...ESPECIALLY BACK ACROSS THE THUMB REGION. WITH JUST PARTIAL
INSOLATION EXPECTED...LOOKING AT MAXES COMING UP JUST SHORT OF 70
DEGREES. WE SHOULD HOWEVER HAVE NO PROBLEM CLIMBING INTO THE 70S ON
THURSDAY AHEAD OF A COLD FRONT...WITH GOOD WARM ADVECTION ALLOWING
925 MB TEMPS TO CLIMB INTO THE UPPER TEENS TO LOWER 20S PER 00Z
EURO. HOWEVER...WITH INCREASING AND THICKENING CLOUDS...BACKED
SOUTHEAST FLOW AT THE SURFACE...BOUNDARY LAYER MIXING WILL PROBABLY
COME UP JUST SHORT OF 925 MB AND WILL HOLD MAXES IN THE MID TO
UPPER 70S.

WITH A VERY GOOD MOISTURE FEED...PW VALUES IN EXCESS OF 1.5
INCHES...COUPLED WITH GOOD HEIGHT FALLS AND MODEST INSTABILITY
THURSDAY NIGHT...RAIN SHOWERS CAN BE EXPECTED...WITH EVEN COLDER AIR
ON TAP FOR THE WEEKEND AS UPPER LEVEL ENERGY OVER THE GULF OF ALASKA
AND OFF THE COAST OF BRITISH COLUMBIA/PACIFIC NORTHWEST CONSOLIDATE
OVER THE GREAT LAKES REGION...LEADING TO DEEP 500 MB LOW. IN
FACT...THE LONGWAVE UPPER LEVEL TROUGH AXIS WILL BE ATTEMPTING TO GO
SLIGHTLY NEGATIVE FRIDAY MORNING...WHICH IS YIELDING A SLOWER
FRONTAL PASSAGE COMPARED TO LAST NIGHT...AND IT APPEARS SHOWERS WILL
LIKELY LINGER INTO FRIDAY. COLD CYCLONIC FLOW AND 850 MB TEMPS
FALLING BELOW ZERO OVER THE WEEKEND WILL LIKELY TRANSLATE TO AT
LEAST SCATTERED LAKE ENHANCED SHOWERS AND MOSTLY CLOUDY SKIES...WITH
FORECASTED 850 MB TEMPS OF -2 C YIELDING HIGHS ONLY IN THE LOW TO
MID 50S ON SATURDAY.

MARINE...

A STRONG COLD FRONT WILL CLEAR THE CENTRAL GREAT LAKES THIS
MORNING...WITH RELATIVELY SHORT LIVED WINDS OF 15 TO 20 KNOTS WITH
GUSTS TO 25 KNOTS ACROSS CENTRAL AND SOUTHERN SECTIONS OF LAKE
HURON.  THIS WILL PROMPT AN INCREASE IN WAVE HEIGHTS...WITH HEIGHTS
TOPPING OUT SLIGHTLY ABOVE 4 FEET OVER MUCH OF SOUTHERN LAKE
HURON...AND THE PREVIOUS SMALL CRAFT ADVISORIES WILL CONTINUE
THROUGH THE DAY. WINDS WILL DIMINISH BY TONIGHT AS HIGH PRESSURE
BUILDS BACK INTO THE REGION...BUT THE NORTHEAST DIRECTION WILL
MAINTAIN SOME MODEST WAVES OVER THE NEARSHORE WATERS. LIGHT WINDS
AND LOW WAVES WILL PERSIST WEDNESDAY INTO THURSDAY.
HOWEVER...SOUTHERLY WINDS DEVELOPING AHEAD OF A COLD FRONT LATE
THURSDAY COULD RESULT IN WINDS UP TO 30 KNOTS OVER THE OPEN WATERS
OF LAKE HURON THURSDAY NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...UNTIL 6 PM TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....SC
SHORT TERM...SC
LONG TERM....SF
MARINE.......SF


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







000
FXUS63 KDTX 300735
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
335 AM EDT TUE SEP 30 2014

.SHORT TERM...TODAY AND TONIGHT

LOW LEVEL COLD AIR ADVECTION WILL PREVAIL THROUGH THE MORNING BEHIND
THE SURFACE COLD FRONT WHICH EXITED THE FORECAST AREA SHORTLY AFTER
06Z. LINGERING POST FRONTAL SHOWERS WILL EXIT TO THE SOUTHEAST OF
THE STATE BEFORE DAYBREAK. THE SHOWERS OVERNIGHT DEVELOPED WITHIN A
RIBBON OF STRONG LARGE SCALE ASCENT ALONG THE LEAD EDGE OF AN
AMPLIFYING UPPER WAVE. RECENT WATER VAPOR IMAGERY ALREADY SHOWS THE
EVOLUTION OF THIS SYSTEM INTO A CLOSED MID LEVEL LOW...WHICH IS
FORECAST TO ROTATE ACROSS THE THUMB THIS MORNING AND INTO NE OHIO
THIS AFTERNOON. THE ASSOCIATED SFC LOW...NOW LOCATED OVER SRN
ONTARIO...WILL IN TURN TRACK INTO WRN PA/WV THIS AFTERNOON.

RESIDUAL LOW LEVEL MOISTURE AND A DEEPENING POST FRONTAL INVERSION
HAS LED TO A STRATUS DECK NOW EXTENDING ALL THE WAY TO SRN LAKE
SUPERIOR. THIS INVERSION WILL ONLY DEEPEN DURING THE COURSE OF THE
MORNING AS 925MB TEMPS FALL THROUGH THE SINGLE DIGITS. LOW CLOUDS
WILL THUS REMAIN IN PLACE INTO AT LEAST LATE EVENING. THIS WILL
LIMIT ANY DIURNAL RECOVERY AND HOLD DAYTIME TEMPS IN THE 50S. THE
EVOLVING COMPACT MID LEVEL LOW WILL SUPPORT THE DEVELOPMENT OF AN
ENHANCED REGION OF MID LEVEL DEFORMATION /TROWEL FEATURE/ TARGETING
NRN/CNTL LAKE HURON AND NE LOWER MI. MODEL SOLUTIONS THEN INDICATE
THIS FEATURE FALLING APART AS IT ADVANCES INTO SE MI TONIGHT AS THE
UPPER LOW WEAKENS AND QUICKLY ADVANCES EAST. SO THE BETTER FORCING
WILL REMAIN NORTH OF THE AREA TODAY. HOWEVER...MODEL SOUNDINGS ARE
VERY SUPPORTIVE OF DRIZZLE TODAY /RADAR AND SFC OBS OVER NRN LOWER
MI OVERNIGHT HAVE ALSO BEEN SHOWING A LOT OF DRIZZLE/. THIS IS DUE
TO A MOIST BOUNDARY LAYER...LOW CLOUD BASES...SUBSTANTIAL DRY AIR
ABOVE THE INVERSION...AND GOOD DIRECTIONAL SHEAR NEAR THE TOP OF THE
MOIST LAYER. THE DRIZZLE IS EXPECTED TO BE QUITE WIDESPREAD OVER
MUCH OF THE THUMB TODAY AS N-NW FLOW OVER LAKE HURON ADDS A LITTLE
BETTER MOISTURE TO THE BOUNDARY LAYER AND ENHANCES CONVERGENCE ALONG
THE SHORELINE.

SFC RIDGING WILL BUILD ACROSS LOWER MI TONIGHT...WHILE ENHANCED
THERMAL TROUGHING WILL RESIDE OVER LAKE HURON. THE FLOW ABOVE THE
BOUNDARY LAYER WILL TURN TOWARD THE EAST WHICH WILL ACTUALLY SUPPORT
SOME LOW LEVEL WARM AIR ADVECTION. THIS WILL WEAKEN /POSSIBLY EVEN
ERODE/ THE LOW LEVEL INVERSION AND MAY SUPPORT SOME CLEARING ACROSS
AT LEAST THE WRN PORTIONS OF THE AREA AS THE SFC HIGH BUILDS IN FROM
THE NORTH. CLEARING POTENTIAL STILL HOWEVER CARRIES A LOW CONFIDENCE
AS THE EASTERLY FLOW WILL ALSO ADVECT SOME HIGHER MOISTURE IN FROM
THE EAST. SO FOG AND/OR ADDITIONAL STRATUS DEVELOPMENT SEEM
POSSIBLE. THE POTENTIAL CLOUD COVER AND LOW LEVEL MOISTURE ADVECTION
WILL WARRANT A LIMITED DROP IN TEMPS TONIGHT /LOWS FROM THE MID 40S
TO LOW 50S/.

&&

.LONG TERM...

CONFIDENCE IS NOT VERY HIGH IN LOW CLOUDS SCOURING OUT COMPLETELY
ON WEDNESDAY...AS NAM/GFS/GEM/EURO ALL SUGGESTING SOME 925-850 MB
RESIDUAL MOISTURE UNDERNEATH THE MODEST UPPER LEVEL
RIDGE...ESPECIALLY BACK ACROSS THE THUMB REGION. WITH JUST PARTIAL
INSOLATION EXPECTED...LOOKING AT MAXES COMING UP JUST SHORT OF 70
DEGREES. WE SHOULD HOWEVER HAVE NO PROBLEM CLIMBING INTO THE 70S ON
THURSDAY AHEAD OF A COLD FRONT...WITH GOOD WARM ADVECTION ALLOWING
925 MB TEMPS TO CLIMB INTO THE UPPER TEENS TO LOWER 20S PER 00Z
EURO. HOWEVER...WITH INCREASING AND THICKENING CLOUDS...BACKED
SOUTHEAST FLOW AT THE SURFACE...BOUNDARY LAYER MIXING WILL PROBABLY
COME UP JUST SHORT OF 925 MB AND WILL HOLD MAXES IN THE MID TO
UPPER 70S.

WITH A VERY GOOD MOISTURE FEED...PW VALUES IN EXCESS OF 1.5
INCHES...COUPLED WITH GOOD HEIGHT FALLS AND MODEST INSTABILITY
THURSDAY NIGHT...RAIN SHOWERS CAN BE EXPECTED...WITH EVEN COLDER AIR
ON TAP FOR THE WEEKEND AS UPPER LEVEL ENERGY OVER THE GULF OF ALASKA
AND OFF THE COAST OF BRITISH COLUMBIA/PACIFIC NORTHWEST CONSOLIDATE
OVER THE GREAT LAKES REGION...LEADING TO DEEP 500 MB LOW. IN
FACT...THE LONGWAVE UPPER LEVEL TROUGH AXIS WILL BE ATTEMPTING TO GO
SLIGHTLY NEGATIVE FRIDAY MORNING...WHICH IS YIELDING A SLOWER
FRONTAL PASSAGE COMPARED TO LAST NIGHT...AND IT APPEARS SHOWERS WILL
LIKELY LINGER INTO FRIDAY. COLD CYCLONIC FLOW AND 850 MB TEMPS
FALLING BELOW ZERO OVER THE WEEKEND WILL LIKELY TRANSLATE TO AT
LEAST SCATTERED LAKE ENHANCED SHOWERS AND MOSTLY CLOUDY SKIES...WITH
FORECASTED 850 MB TEMPS OF -2 C YIELDING HIGHS ONLY IN THE LOW TO
MID 50S ON SATURDAY.

&&

.MARINE...

A STRONG COLD FRONT WILL CLEAR THE CENTRAL GREAT LAKES THIS
MORNING...WITH RELATIVELY SHORT LIVED WINDS OF 15 TO 20 KNOTS WITH
GUSTS TO 25 KNOTS ACROSS CENTRAL AND SOUTHERN SECTIONS OF LAKE
HURON.  THIS WILL PROMPT AN INCREASE IN WAVE HEIGHTS...WITH HEIGHTS
TOPPING OUT SLIGHTLY ABOVE 4 FEET OVER MUCH OF SOUTHERN LAKE
HURON...AND THE PREVIOUS SMALL CRAFT ADVISORIES WILL CONTINUE
THROUGH THE DAY. WINDS WILL DIMINISH BY TONIGHT AS HIGH PRESSURE
BUILDS BACK INTO THE REGION...BUT THE NORTHEAST DIRECTION WILL
MAINTAIN SOME MODEST WAVES OVER THE NEARSHORE WATERS. LIGHT WINDS
AND LOW WAVES WILL PERSIST WEDNESDAY INTO THURSDAY.
HOWEVER...SOUTHERLY WINDS DEVELOPING AHEAD OF A COLD FRONT LATE
THURSDAY COULD RESULT IN WINDS UP TO 30 KNOTS OVER THE OPEN WATERS
OF LAKE HURON THURSDAY NIGHT.

&&

.AVIATION...ISSUED 1212 AM EDT TUE SEP 30 2014

//DISCUSSION...

AVIATION WEATHER IN SE MICHIGAN REMAINS TIED TO THE PASSAGE OF A
STRONG COLD FRONT...NOT AS MUCH WIND AS IN TEMPERATURE...AND THE
RESULTING COLDER AIR MASS SETTLING IN BEHIND THE FRONT. AT PRESS
TIME...THE FRONT ONLY HAD TO MOVE THROUGH THE DTW TERMINAL CORRIDOR
WITH MODEST SPEED BUT SHARP WIND SHIFT TO THE NORTHWEST AND A
PATTERN OF SHOWERS WITH MARGINAL MVFR RESTRICTION. THE RAIN WILL
ONLY LAST A FEW HOURS AND THEN LEAVE WIDESPREAD IFR CEILING THROUGH
THE MID MORNING IN THE DTW AREA...MVFR FARTHER NORTH TOWARD MBS.
CEILING WILL GRADUALLY RISE DURING THE DAY BUT REMAIN LOCKED IN AT
MVFR OVER COOL NORTH WIND.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET THROUGH TODAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...UNTIL 6 PM TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...SC
LONG TERM....SF
MARINE.......SF
AVIATION.....BT


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








000
FXUS63 KDTX 300735
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
335 AM EDT TUE SEP 30 2014

.SHORT TERM...TODAY AND TONIGHT

LOW LEVEL COLD AIR ADVECTION WILL PREVAIL THROUGH THE MORNING BEHIND
THE SURFACE COLD FRONT WHICH EXITED THE FORECAST AREA SHORTLY AFTER
06Z. LINGERING POST FRONTAL SHOWERS WILL EXIT TO THE SOUTHEAST OF
THE STATE BEFORE DAYBREAK. THE SHOWERS OVERNIGHT DEVELOPED WITHIN A
RIBBON OF STRONG LARGE SCALE ASCENT ALONG THE LEAD EDGE OF AN
AMPLIFYING UPPER WAVE. RECENT WATER VAPOR IMAGERY ALREADY SHOWS THE
EVOLUTION OF THIS SYSTEM INTO A CLOSED MID LEVEL LOW...WHICH IS
FORECAST TO ROTATE ACROSS THE THUMB THIS MORNING AND INTO NE OHIO
THIS AFTERNOON. THE ASSOCIATED SFC LOW...NOW LOCATED OVER SRN
ONTARIO...WILL IN TURN TRACK INTO WRN PA/WV THIS AFTERNOON.

RESIDUAL LOW LEVEL MOISTURE AND A DEEPENING POST FRONTAL INVERSION
HAS LED TO A STRATUS DECK NOW EXTENDING ALL THE WAY TO SRN LAKE
SUPERIOR. THIS INVERSION WILL ONLY DEEPEN DURING THE COURSE OF THE
MORNING AS 925MB TEMPS FALL THROUGH THE SINGLE DIGITS. LOW CLOUDS
WILL THUS REMAIN IN PLACE INTO AT LEAST LATE EVENING. THIS WILL
LIMIT ANY DIURNAL RECOVERY AND HOLD DAYTIME TEMPS IN THE 50S. THE
EVOLVING COMPACT MID LEVEL LOW WILL SUPPORT THE DEVELOPMENT OF AN
ENHANCED REGION OF MID LEVEL DEFORMATION /TROWEL FEATURE/ TARGETING
NRN/CNTL LAKE HURON AND NE LOWER MI. MODEL SOLUTIONS THEN INDICATE
THIS FEATURE FALLING APART AS IT ADVANCES INTO SE MI TONIGHT AS THE
UPPER LOW WEAKENS AND QUICKLY ADVANCES EAST. SO THE BETTER FORCING
WILL REMAIN NORTH OF THE AREA TODAY. HOWEVER...MODEL SOUNDINGS ARE
VERY SUPPORTIVE OF DRIZZLE TODAY /RADAR AND SFC OBS OVER NRN LOWER
MI OVERNIGHT HAVE ALSO BEEN SHOWING A LOT OF DRIZZLE/. THIS IS DUE
TO A MOIST BOUNDARY LAYER...LOW CLOUD BASES...SUBSTANTIAL DRY AIR
ABOVE THE INVERSION...AND GOOD DIRECTIONAL SHEAR NEAR THE TOP OF THE
MOIST LAYER. THE DRIZZLE IS EXPECTED TO BE QUITE WIDESPREAD OVER
MUCH OF THE THUMB TODAY AS N-NW FLOW OVER LAKE HURON ADDS A LITTLE
BETTER MOISTURE TO THE BOUNDARY LAYER AND ENHANCES CONVERGENCE ALONG
THE SHORELINE.

SFC RIDGING WILL BUILD ACROSS LOWER MI TONIGHT...WHILE ENHANCED
THERMAL TROUGHING WILL RESIDE OVER LAKE HURON. THE FLOW ABOVE THE
BOUNDARY LAYER WILL TURN TOWARD THE EAST WHICH WILL ACTUALLY SUPPORT
SOME LOW LEVEL WARM AIR ADVECTION. THIS WILL WEAKEN /POSSIBLY EVEN
ERODE/ THE LOW LEVEL INVERSION AND MAY SUPPORT SOME CLEARING ACROSS
AT LEAST THE WRN PORTIONS OF THE AREA AS THE SFC HIGH BUILDS IN FROM
THE NORTH. CLEARING POTENTIAL STILL HOWEVER CARRIES A LOW CONFIDENCE
AS THE EASTERLY FLOW WILL ALSO ADVECT SOME HIGHER MOISTURE IN FROM
THE EAST. SO FOG AND/OR ADDITIONAL STRATUS DEVELOPMENT SEEM
POSSIBLE. THE POTENTIAL CLOUD COVER AND LOW LEVEL MOISTURE ADVECTION
WILL WARRANT A LIMITED DROP IN TEMPS TONIGHT /LOWS FROM THE MID 40S
TO LOW 50S/.

&&

.LONG TERM...

CONFIDENCE IS NOT VERY HIGH IN LOW CLOUDS SCOURING OUT COMPLETELY
ON WEDNESDAY...AS NAM/GFS/GEM/EURO ALL SUGGESTING SOME 925-850 MB
RESIDUAL MOISTURE UNDERNEATH THE MODEST UPPER LEVEL
RIDGE...ESPECIALLY BACK ACROSS THE THUMB REGION. WITH JUST PARTIAL
INSOLATION EXPECTED...LOOKING AT MAXES COMING UP JUST SHORT OF 70
DEGREES. WE SHOULD HOWEVER HAVE NO PROBLEM CLIMBING INTO THE 70S ON
THURSDAY AHEAD OF A COLD FRONT...WITH GOOD WARM ADVECTION ALLOWING
925 MB TEMPS TO CLIMB INTO THE UPPER TEENS TO LOWER 20S PER 00Z
EURO. HOWEVER...WITH INCREASING AND THICKENING CLOUDS...BACKED
SOUTHEAST FLOW AT THE SURFACE...BOUNDARY LAYER MIXING WILL PROBABLY
COME UP JUST SHORT OF 925 MB AND WILL HOLD MAXES IN THE MID TO
UPPER 70S.

WITH A VERY GOOD MOISTURE FEED...PW VALUES IN EXCESS OF 1.5
INCHES...COUPLED WITH GOOD HEIGHT FALLS AND MODEST INSTABILITY
THURSDAY NIGHT...RAIN SHOWERS CAN BE EXPECTED...WITH EVEN COLDER AIR
ON TAP FOR THE WEEKEND AS UPPER LEVEL ENERGY OVER THE GULF OF ALASKA
AND OFF THE COAST OF BRITISH COLUMBIA/PACIFIC NORTHWEST CONSOLIDATE
OVER THE GREAT LAKES REGION...LEADING TO DEEP 500 MB LOW. IN
FACT...THE LONGWAVE UPPER LEVEL TROUGH AXIS WILL BE ATTEMPTING TO GO
SLIGHTLY NEGATIVE FRIDAY MORNING...WHICH IS YIELDING A SLOWER
FRONTAL PASSAGE COMPARED TO LAST NIGHT...AND IT APPEARS SHOWERS WILL
LIKELY LINGER INTO FRIDAY. COLD CYCLONIC FLOW AND 850 MB TEMPS
FALLING BELOW ZERO OVER THE WEEKEND WILL LIKELY TRANSLATE TO AT
LEAST SCATTERED LAKE ENHANCED SHOWERS AND MOSTLY CLOUDY SKIES...WITH
FORECASTED 850 MB TEMPS OF -2 C YIELDING HIGHS ONLY IN THE LOW TO
MID 50S ON SATURDAY.

&&

.MARINE...

A STRONG COLD FRONT WILL CLEAR THE CENTRAL GREAT LAKES THIS
MORNING...WITH RELATIVELY SHORT LIVED WINDS OF 15 TO 20 KNOTS WITH
GUSTS TO 25 KNOTS ACROSS CENTRAL AND SOUTHERN SECTIONS OF LAKE
HURON.  THIS WILL PROMPT AN INCREASE IN WAVE HEIGHTS...WITH HEIGHTS
TOPPING OUT SLIGHTLY ABOVE 4 FEET OVER MUCH OF SOUTHERN LAKE
HURON...AND THE PREVIOUS SMALL CRAFT ADVISORIES WILL CONTINUE
THROUGH THE DAY. WINDS WILL DIMINISH BY TONIGHT AS HIGH PRESSURE
BUILDS BACK INTO THE REGION...BUT THE NORTHEAST DIRECTION WILL
MAINTAIN SOME MODEST WAVES OVER THE NEARSHORE WATERS. LIGHT WINDS
AND LOW WAVES WILL PERSIST WEDNESDAY INTO THURSDAY.
HOWEVER...SOUTHERLY WINDS DEVELOPING AHEAD OF A COLD FRONT LATE
THURSDAY COULD RESULT IN WINDS UP TO 30 KNOTS OVER THE OPEN WATERS
OF LAKE HURON THURSDAY NIGHT.

&&

.AVIATION...ISSUED 1212 AM EDT TUE SEP 30 2014

//DISCUSSION...

AVIATION WEATHER IN SE MICHIGAN REMAINS TIED TO THE PASSAGE OF A
STRONG COLD FRONT...NOT AS MUCH WIND AS IN TEMPERATURE...AND THE
RESULTING COLDER AIR MASS SETTLING IN BEHIND THE FRONT. AT PRESS
TIME...THE FRONT ONLY HAD TO MOVE THROUGH THE DTW TERMINAL CORRIDOR
WITH MODEST SPEED BUT SHARP WIND SHIFT TO THE NORTHWEST AND A
PATTERN OF SHOWERS WITH MARGINAL MVFR RESTRICTION. THE RAIN WILL
ONLY LAST A FEW HOURS AND THEN LEAVE WIDESPREAD IFR CEILING THROUGH
THE MID MORNING IN THE DTW AREA...MVFR FARTHER NORTH TOWARD MBS.
CEILING WILL GRADUALLY RISE DURING THE DAY BUT REMAIN LOCKED IN AT
MVFR OVER COOL NORTH WIND.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET THROUGH TODAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...UNTIL 6 PM TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...SC
LONG TERM....SF
MARINE.......SF
AVIATION.....BT


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







000
FXUS63 KDTX 300412
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1212 AM EDT TUE SEP 30 2014

.AVIATION...

//DISCUSSION...

AVIATION WEATHER IN SE MICHIGAN REMAINS TIED TO THE PASSAGE OF A
STRONG COLD FRONT...NOT AS MUCH WIND AS IN TEMPERATURE...AND THE
RESULTING COLDER AIR MASS SETTLING IN BEHIND THE FRONT. AT PRESS
TIME...THE FRONT ONLY HAD TO MOVE THROUGH THE DTW TERMINAL CORRIDOR
WITH MODEST SPEED BUT SHARP WIND SHIFT TO THE NORTHWEST AND A
PATTERN OF SHOWERS WITH MARGINAL MVFR RESTRICTION. THE RAIN WILL
ONLY LAST A FEW HOURS AND THEN LEAVE WIDESPREAD IFR CEILING THROUGH
THE MID MORNING IN THE DTW AREA...MVFR FARTHER NORTH TOWARD MBS.
CEILING WILL GRADUALLY RISE DURING THE DAY BUT REMAIN LOCKED IN AT
MVFR OVER COOL NORTH WIND.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET THROUGH TODAY.

&&

.PREV DISCUSSION...ISSUED 907 PM EDT MON SEP 29 2014

UPDATE...

A STRONG COLD FRONT CONTINUES TO SLIDE THROUGH SE MICHIGAN TONIGHT
AND WILL BRING PRONOUNCED CHANGES TO THE WEATHER IN OUR AREA. THE
FRONT IS NOT PACKING MUCH OF A WIND PUNCH BUT IS BRINGING A SHARP
WIND SHIFT AND TEMPERATURE DECREASE. THE TEMPERATURE DECREASE WAS
MORE DRAMATIC BEFORE SUNSET OVER NORTH SECTIONS WHILE AFTERNOON
TEMPS WERE PUSHING 80...BUT WILL NOW BE MASKED A BIT MORE BY
COOLER READINGS AFTER SUNSET OVER THE REST OF SE MICHIGAN. THE
FORECAST TIMING OF THE FRONTAL PASSAGE LOOKS SOLID IN THE GOING
PACKAGE.

EARLIER IN THE EVENING...THE THERE WAS JUST ENOUGH SURFACE BASED
INSTABILITY GENERATED BY DEWPOINT NEAR 60 TO FIRE OFF SOME
THUNDERSTORMS WITHIN THE FRONTAL ZONE OVER THE SAGINAW VALLEY AND
THUMB. FORCING WAS ALSO BOOSTED BY STRONG DYNAMIC LIFT SUPPLIED BY
THE THE UPPER WAVE...AND THIS WILL BE THE PRIMARY FORCING FOR
SHOWERS FOR THE REST OF THE NIGHT WITHIN THE LOW TO MID LEVEL
THETA-E RIDGE COINCIDENT WITH THE FRONT. THE LOSS OF DAYTIME
HEATING WILL CHALLENGE THE SYSTEM TO PRODUCE MORE THUNDERSTORM
ACTIVITY BUT THE SYSTEM IS STRONG AND PLAN TO MAINTAIN A CHANCE IN
THE FORECAST WITHIN A NEARLY SOLID BAND OF SHOWERS. THE
CATEGORICAL POP FORECAST LOOKS GOOD WITH JUST MINOR REFINEMENT TO
TIMING BEFORE THE PATTERN EXITS SE MICHIGAN BY SUNRISE. THE FRONT
WILL THEN LEAVE CLOUDY AND COOLER CONDITIONS IN PLACE THROUGH
TUESDAY MORNING.

PREV DISCUSSION...ISSUED 344 PM EDT MON SEP 29 2014

SHORT TERM...THROUGH TONIGHT

QUIET AND WARM CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE
AFTERNOON AND INTO THE EVENING BEFORE AN APPROACHING COLD FRONT
USHERS IN BIG CHANGES FOR THE OVERNIGHT HOURS AND ESPECIALLY
TOMORROW.

UPPER TROUGH DROPPING FROM CANADA INTO NORTHERN MICHIGAN WILL DEEPEN
INTO A CLOSED LOW AS IT DROPS ACROSS LOWER MICHIGAN TONIGHT. AT THE
SURFACE...THIS WILL PUSH THE AREA OF SURFACE LOW PRESSURE CENTERED
SOUTH OF ALPENA SOUTHEAST ACROSS LAKE HURON AND INTO ONTARIO
TONIGHT. STRONG SURFACE COLD FRONT WILL TRAIL BEHIND THE
LOW...DROPPING THROUGH SOUTHEAST MICHIGAN THIS EVENING AND OVERNIGHT
(9PM THROUGH 6 AM). STILL LOOKING LIKE A GOOD SHOT FOR RAIN TONIGHT
ALONG THE FRONT WITH UPPER DIFFLUENCE AND GOOD UPPER HEIGHTS FALLS
POSITIONED ABOVE THE FRONT (SOME FGEN AS WELL)...AND AS A MODEST
SURGE OF THETA-E OCCURS. CONTINUE TO THINK THAT THE WINDOW FOR RAIN
SHOWERS AT ANY GIVEN LOCATION IS ONLY 2 TO 4 HOURS WIDE...WHICH
AGREES WELL WITH CURRENT RADAR PRESENTATION OVER NORTHERN MICHIGAN
AND WISCONSIN. (AREAS OF DRIZZLE MAY HOWEVER DEVELOP AFTER THE FRONT
SLIDES THROUGH AND DRIER AIR ALOFT WORKS IN.) SOME THUNDER WILL ALSO
BE POSSIBLE WITH STEEPENING MID-LEVEL LAPSE RATES AND MODEL
CROSS-SECTIONS SHOWING SOME CONVECTIVE INSTABILITY (MOSTLY ALOFT) AS
THE FRONT DROPS THROUGH. THERE WERE SOME THUNDER OVER THE U.P. LATE
LAST NIGHT ALONG THE FRONT.

TEMPERATURE GRADIENT ACROSS THE FRONT RIGHT NOW IS IMPRESSIVE...WITH
LOW 50S RIGHT NOW OVER NORTHERN LOWER MI AND UPPER 70S ACROSS
CENTRAL MI (40S IN THE U.P!). THE TEMPERATURE IN TRAVERSE CITY FELL
FROM 70 TO 58 DEGREES IN ONLY TWO HOURS THIS AFTERNOON AS THE FRONT
DROPPED ACROSS. OUR WARM TEMPS SHOULD HOLD THROUGH THE DAYLIGHT
HOURS BEFORE THE FRONT SLIDES THROUGH...RIGHT AS TEMPERATURES WOULD
COOL ANYHOW. WIND...CLOUDS...AND RAIN SHOULD PREVENT TEMPS FROM
GETTING TOO CHILLY OVERNIGHT...ESPECIALLY WITH BEST COLD AIR
ADVECTION HOLDING OFF UNTIL OVERNIGHT. MIN TEMPS ARE EXPECTED TO RUN
FROM THE MID 40S OVER THE THUMB/SAGINAW VALLEY TO THE MID 50S IN THE
DETROIT HEAT ISLAND.

LONG TERM...

564 DM CLOSED MID LEVEL CIRCULATION CENTERED OVER THE EASTERN
THUMB/SOUTHERN LAKE HURON TUESDAY MORNING WILL PIVOT TO THE EAST
THROUGH THE DAY...ALLOWING A DEEPER NORTHERLY FLOW TO TAKE HOLD
LOCALLY.  A SOLID PERIOD OF COLD AIR ADVECTION ALREADY UNDERWAY
POST-DAYBREAK WILL EASE BY MIDDAY...THE COLDEST CORE OF THIS AIRMASS
/850 MB TEMPS OF 4C/ CENTERING OVERHEAD BY AFTERNOON AND EVENING.
SUBSTANTIAL POST-FRONTAL LOW LEVEL MOISTURE WILL REMAIN TUCKED
BENEATH A BURGEONING INVERSION.  THIS COMBINED WITH STEEPENING LOW
LEVEL LAPSE RATES WILL ENSURE AN EXTENSIVE STRATUS FIELD REMAINS
PREVALENT THROUGHOUT THE DAY.  MOISTURE DEPTH MAY PROVE ADEQUATE
TOWARD GENERATING A FEW POCKETS OF LIGHT RAIN/DRIZZLE...STILL WORTHY
OF A SMALL POP MENTION.  GREATEST POTENTIAL WILL LIKELY EXIST ACROSS
THE THUMB UNDER SOME RENEWED CVA AS A TRAILING PIECE OF VORTICITY
WRAPS BACK AROUND THE EXITING LOW.  THE TIMING/STRENGTH OF THE
ADVECTIVE PROCESS AND THE LACK OF BETTER INSOLATION WILL CONFINE
HIGHS LARGELY IN THE MID AND UPPER 50S.

LOW LEVEL FLOW WILL VEER TO NORTHEASTERLY BY TUESDAY NIGHT AS THE
CENTER OF EXPANDING HIGH PRESSURE WORKS ACROSS ONTARIO.  THE
EXISTING CANOPY OF STRATUS WILL BUDGE LITTLE UNDER THIS SETUP...THE
ADDED CONTRIBUTION OFF LAKE HURON REINFORCING A SUFFICIENTLY
DEEP MOIST SUB-INVERSION LAYER.  LOWS UPPER 40S/LOWER 50S.

HIGH PRESSURE SETTLES IN FOR WEDNESDAY AS A NARROW UPPER RIDGE AXIS
CENTERS OVER THE REGION.  THIS WILL PROMPT A GRADUAL RELEASE OF THE
CLOUD COVER AS THE COMBINATION OF DAYTIME HEATING/MIXING AND
STRENGTHENING MID LEVEL SUBSIDENCE SHRINKS THE EXISTING MOIST LAYER.
A MODERATING AIR MASS GIVEN THE INCREASING THICKNESS FIELD AND SOME
LATE DAY INSOLATION WILL PROVIDE AN INCREMENTAL BOOST TO HIGHS.
850 MB TEMPERATURES ARE PROJECTED TO CLIMB BACK INTO THE 10C RANGE.
THIS WOULD SUPPORT READINGS WITHIN THE 65 TO 70F RANGE...ASSUMING
CLOUD COVER DOES NOT REMAIN PROBLEMATIC WELL INTO THE DAY.

TEMPERATURES WILL RECOVER NICELY FOR THE FIRST HALF OF THURSDAY
AHEAD OF AN APPROACHING COLD FRONT. EXPECT PROBABLY THE LAST RUN AT
80 FOR THE YEAR AS SOUTHERLY DRYING WINDS WILL TRY TO AID
INSOLATION. THE RAIN EVENT THURSDAY NIGHT WILL AVERAGE 0.5 TO 0.75
INCH OF QPF ACROSS THE CWA...WITH LOCALLY HIGHER AMOUNTS. EXPECT A
RAW WEEKEND AS TEMPERATURES DROP STEEPLY AND WINDS PICK UP TO GUST
OVER 25 MPH.

MARINE...

COLD FRONT MOVES THROUGH THE CENTRAL GREAT LAKES TONIGHT. NORTHERLY
WINDS WILL STRENGTHEN BEHIND THIS FRONT LATE TONIGHT AND EARLY
TUESDAY.  WINDS OF 15 TO 20 KNOTS WITH GUSTS TO 25 KNOTS ACROSS
CENTRAL AND SOUTHERN SECTIONS OF LAKE HURON.  THIS WILL PROMPT AN
INCREASE IN WAVE HEIGHTS...WITH APPROPRIATE SMALL CRAFT ADVISORIES
NOW IN PLACE.  WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH
PRESSURE BUILDS BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL
PERSIST WEDNESDAY AND THURSDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...UNTIL 6 PM TUESDAY.

LAKE ST CLAIR...NONE.

MI WATERS OF LAKE ERIE...NONE.

&&

$$

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


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









000
FXUS63 KDTX 300107
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
907 PM EDT MON SEP 29 2014

.UPDATE...

A STRONG COLD FRONT CONTINUES TO SLIDE THROUGH SE MICHIGAN TONIGHT
AND WILL BRING PRONOUNCED CHANGES TO THE WEATHER IN OUR AREA. THE
FRONT IS NOT PACKING MUCH OF A WIND PUNCH BUT IS BRINGING A SHARP
WIND SHIFT AND TEMPERATURE DECREASE. THE TEMPERATURE DECREASE WAS
MORE DRAMATIC BEFORE SUNSET OVER NORTH SECTIONS WHILE AFTERNOON
TEMPS WERE PUSHING 80...BUT WILL NOW BE MASKED A BIT MORE BY
COOLER READINGS AFTER SUNSET OVER THE REST OF SE MICHIGAN. THE
FORECAST TIMING OF THE FRONTAL PASSAGE LOOKS SOLID IN THE GOING
PACKAGE.

EARLIER IN THE EVENING...THE THERE WAS JUST ENOUGH SURFACE BASED
INSTABILITY GENERATED BY DEWPOINT NEAR 60 TO FIRE OFF SOME
THUNDERSTORMS WITHIN THE FRONTAL ZONE OVER THE SAGINAW VALLEY AND
THUMB. FORCING WAS ALSO BOOSTED BY STRONG DYNAMIC LIFT SUPPLIED BY
THE THE UPPER WAVE...AND THIS WILL BE THE PRIMARY FORCING FOR
SHOWERS FOR THE REST OF THE NIGHT WITHIN THE LOW TO MID LEVEL
THETA-E RIDGE COINCIDENT WITH THE FRONT. THE LOSS OF DAYTIME
HEATING WILL CHALLENGE THE SYSTEM TO PRODUCE MORE THUNDERSTORM
ACTIVITY BUT THE SYSTEM IS STRONG AND PLAN TO MAINTAIN A CHANCE IN
THE FORECAST WITHIN A NEARLY SOLID BAND OF SHOWERS. THE
CATEGORICAL POP FORECAST LOOKS GOOD WITH JUST MINOR REFINEMENT TO
TIMING BEFORE THE PATTERN EXITS SE MICHIGAN BY SUNRISE. THE FRONT
WILL THEN LEAVE CLOUDY AND COOLER CONDITIONS IN PLACE THROUGH
TUESDAY MORNING.

&&

.AVIATION...ISSUED 657 PM EDT MON SEP 29 2014

//DISCUSSION...

A STRONG COLD FRONT WILL MOVE THROUGH THE TERMINAL CORRIDOR DURING
THE EVENING. WIND SPEED WILL BE MODEST BUT THE WIND SHIFT WILL BE
SHARP TO THE NORTHWEST AND WILL BRING A DRAMATIC CHANGE IN
TEMPERATURE AND CLOUD CONDITIONS ALONG WITH A PATTERN OF SHOWERS AND
ISOLATED THUNDERSTORMS. RAIN WILL WILL ONLY LAST A FEW HOURS AT ANY
ONE STATION BUT CEILING WILL QUICKLY DROP TO MVFR AND THEN IFR FOR
THE BULK OF THE NIGHT. CEILING WILL GRADUALLY RISE DURING TUESDAY
BUT REMAIN LOCKED IN AT MVFR OVER COOL NORTH WIND.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET OVERNIGHT THROUGH
TUESDAY.

&&

.PREV DISCUSSION...ISSUED 344 PM EDT MON SEP 29 2014

SHORT TERM...THROUGH TONIGHT

QUIET AND WARM CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE
AFTERNOON AND INTO THE EVENING BEFORE AN APPROACHING COLD FRONT
USHERS IN BIG CHANGES FOR THE OVERNIGHT HOURS AND ESPECIALLY
TOMORROW.

UPPER TROUGH DROPPING FROM CANADA INTO NORTHERN MICHIGAN WILL DEEPEN
INTO A CLOSED LOW AS IT DROPS ACROSS LOWER MICHIGAN TONIGHT. AT THE
SURFACE...THIS WILL PUSH THE AREA OF SURFACE LOW PRESSURE CENTERED
SOUTH OF ALPENA SOUTHEAST ACROSS LAKE HURON AND INTO ONTARIO
TONIGHT. STRONG SURFACE COLD FRONT WILL TRAIL BEHIND THE
LOW...DROPPING THROUGH SOUTHEAST MICHIGAN THIS EVENING AND OVERNIGHT
(9PM THROUGH 6 AM). STILL LOOKING LIKE A GOOD SHOT FOR RAIN TONIGHT
ALONG THE FRONT WITH UPPER DIFFLUENCE AND GOOD UPPER HEIGHTS FALLS
POSITIONED ABOVE THE FRONT (SOME FGEN AS WELL)...AND AS A MODEST
SURGE OF THETA-E OCCURS. CONTINUE TO THINK THAT THE WINDOW FOR RAIN
SHOWERS AT ANY GIVEN LOCATION IS ONLY 2 TO 4 HOURS WIDE...WHICH
AGREES WELL WITH CURRENT RADAR PRESENTATION OVER NORTHERN MICHIGAN
AND WISCONSIN. (AREAS OF DRIZZLE MAY HOWEVER DEVELOP AFTER THE FRONT
SLIDES THROUGH AND DRIER AIR ALOFT WORKS IN.) SOME THUNDER WILL ALSO
BE POSSIBLE WITH STEEPENING MID-LEVEL LAPSE RATES AND MODEL
CROSS-SECTIONS SHOWING SOME CONVECTIVE INSTABILITY (MOSTLY ALOFT) AS
THE FRONT DROPS THROUGH. THERE WERE SOME THUNDER OVER THE U.P. LATE
LAST NIGHT ALONG THE FRONT.

TEMPERATURE GRADIENT ACROSS THE FRONT RIGHT NOW IS IMPRESSIVE...WITH
LOW 50S RIGHT NOW OVER NORTHERN LOWER MI AND UPPER 70S ACROSS
CENTRAL MI (40S IN THE U.P!). THE TEMPERATURE IN TRAVERSE CITY FELL
FROM 70 TO 58 DEGREES IN ONLY TWO HOURS THIS AFTERNOON AS THE FRONT
DROPPED ACROSS. OUR WARM TEMPS SHOULD HOLD THROUGH THE DAYLIGHT
HOURS BEFORE THE FRONT SLIDES THROUGH...RIGHT AS TEMPERATURES WOULD
COOL ANYHOW. WIND...CLOUDS...AND RAIN SHOULD PREVENT TEMPS FROM
GETTING TOO CHILLY OVERNIGHT...ESPECIALLY WITH BEST COLD AIR
ADVECTION HOLDING OFF UNTIL OVERNIGHT. MIN TEMPS ARE EXPECTED TO RUN
FROM THE MID 40S OVER THE THUMB/SAGINAW VALLEY TO THE MID 50S IN THE
DETROIT HEAT ISLAND.

LONG TERM...

564 DM CLOSED MID LEVEL CIRCULATION CENTERED OVER THE EASTERN
THUMB/SOUTHERN LAKE HURON TUESDAY MORNING WILL PIVOT TO THE EAST
THROUGH THE DAY...ALLOWING A DEEPER NORTHERLY FLOW TO TAKE HOLD
LOCALLY.  A SOLID PERIOD OF COLD AIR ADVECTION ALREADY UNDERWAY
POST-DAYBREAK WILL EASE BY MIDDAY...THE COLDEST CORE OF THIS AIRMASS
/850 MB TEMPS OF 4C/ CENTERING OVERHEAD BY AFTERNOON AND EVENING.
SUBSTANTIAL POST-FRONTAL LOW LEVEL MOISTURE WILL REMAIN TUCKED
BENEATH A BURGEONING INVERSION.  THIS COMBINED WITH STEEPENING LOW
LEVEL LAPSE RATES WILL ENSURE AN EXTENSIVE STRATUS FIELD REMAINS
PREVALENT THROUGHOUT THE DAY.  MOISTURE DEPTH MAY PROVE ADEQUATE
TOWARD GENERATING A FEW POCKETS OF LIGHT RAIN/DRIZZLE...STILL WORTHY
OF A SMALL POP MENTION.  GREATEST POTENTIAL WILL LIKELY EXIST ACROSS
THE THUMB UNDER SOME RENEWED CVA AS A TRAILING PIECE OF VORTICITY
WRAPS BACK AROUND THE EXITING LOW.  THE TIMING/STRENGTH OF THE
ADVECTIVE PROCESS AND THE LACK OF BETTER INSOLATION WILL CONFINE
HIGHS LARGELY IN THE MID AND UPPER 50S.

LOW LEVEL FLOW WILL VEER TO NORTHEASTERLY BY TUESDAY NIGHT AS THE
CENTER OF EXPANDING HIGH PRESSURE WORKS ACROSS ONTARIO.  THE
EXISTING CANOPY OF STRATUS WILL BUDGE LITTLE UNDER THIS SETUP...THE
ADDED CONTRIBUTION OFF LAKE HURON REINFORCING A SUFFICIENTLY
DEEP MOIST SUB-INVERSION LAYER.  LOWS UPPER 40S/LOWER 50S.

HIGH PRESSURE SETTLES IN FOR WEDNESDAY AS A NARROW UPPER RIDGE AXIS
CENTERS OVER THE REGION.  THIS WILL PROMPT A GRADUAL RELEASE OF THE
CLOUD COVER AS THE COMBINATION OF DAYTIME HEATING/MIXING AND
STRENGTHENING MID LEVEL SUBSIDENCE SHRINKS THE EXISTING MOIST LAYER.
A MODERATING AIR MASS GIVEN THE INCREASING THICKNESS FIELD AND SOME
LATE DAY INSOLATION WILL PROVIDE AN INCREMENTAL BOOST TO HIGHS.
850 MB TEMPERATURES ARE PROJECTED TO CLIMB BACK INTO THE 10C RANGE.
THIS WOULD SUPPORT READINGS WITHIN THE 65 TO 70F RANGE...ASSUMING
CLOUD COVER DOES NOT REMAIN PROBLEMATIC WELL INTO THE DAY.

TEMPERATURES WILL RECOVER NICELY FOR THE FIRST HALF OF THURSDAY
AHEAD OF AN APPROACHING COLD FRONT. EXPECT PROBABLY THE LAST RUN AT
80 FOR THE YEAR AS SOUTHERLY DRYING WINDS WILL TRY TO AID
INSOLATION. THE RAIN EVENT THURSDAY NIGHT WILL AVERAGE 0.5 TO 0.75
INCH OF QPF ACROSS THE CWA...WITH LOCALLY HIGHER AMOUNTS. EXPECT A
RAW WEEKEND AS TEMPERATURES DROP STEEPLY AND WINDS PICK UP TO GUST
OVER 25 MPH.

MARINE...

COLD FRONT MOVES THROUGH THE CENTRAL GREAT LAKES TONIGHT. NORTHERLY
WINDS WILL STRENGTHEN BEHIND THIS FRONT LATE TONIGHT AND EARLY
TUESDAY.  WINDS OF 15 TO 20 KNOTS WITH GUSTS TO 25 KNOTS ACROSS
CENTRAL AND SOUTHERN SECTIONS OF LAKE HURON.  THIS WILL PROMPT AN
INCREASE IN WAVE HEIGHTS...WITH APPROPRIATE SMALL CRAFT ADVISORIES
NOW IN PLACE.  WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH
PRESSURE BUILDS BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL
PERSIST WEDNESDAY AND THURSDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.

MI WATERS OF LAKE ERIE...NONE.

&&

$$

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


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









000
FXUS63 KDTX 300107
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
907 PM EDT MON SEP 29 2014

.UPDATE...

A STRONG COLD FRONT CONTINUES TO SLIDE THROUGH SE MICHIGAN TONIGHT
AND WILL BRING PRONOUNCED CHANGES TO THE WEATHER IN OUR AREA. THE
FRONT IS NOT PACKING MUCH OF A WIND PUNCH BUT IS BRINGING A SHARP
WIND SHIFT AND TEMPERATURE DECREASE. THE TEMPERATURE DECREASE WAS
MORE DRAMATIC BEFORE SUNSET OVER NORTH SECTIONS WHILE AFTERNOON
TEMPS WERE PUSHING 80...BUT WILL NOW BE MASKED A BIT MORE BY
COOLER READINGS AFTER SUNSET OVER THE REST OF SE MICHIGAN. THE
FORECAST TIMING OF THE FRONTAL PASSAGE LOOKS SOLID IN THE GOING
PACKAGE.

EARLIER IN THE EVENING...THE THERE WAS JUST ENOUGH SURFACE BASED
INSTABILITY GENERATED BY DEWPOINT NEAR 60 TO FIRE OFF SOME
THUNDERSTORMS WITHIN THE FRONTAL ZONE OVER THE SAGINAW VALLEY AND
THUMB. FORCING WAS ALSO BOOSTED BY STRONG DYNAMIC LIFT SUPPLIED BY
THE THE UPPER WAVE...AND THIS WILL BE THE PRIMARY FORCING FOR
SHOWERS FOR THE REST OF THE NIGHT WITHIN THE LOW TO MID LEVEL
THETA-E RIDGE COINCIDENT WITH THE FRONT. THE LOSS OF DAYTIME
HEATING WILL CHALLENGE THE SYSTEM TO PRODUCE MORE THUNDERSTORM
ACTIVITY BUT THE SYSTEM IS STRONG AND PLAN TO MAINTAIN A CHANCE IN
THE FORECAST WITHIN A NEARLY SOLID BAND OF SHOWERS. THE
CATEGORICAL POP FORECAST LOOKS GOOD WITH JUST MINOR REFINEMENT TO
TIMING BEFORE THE PATTERN EXITS SE MICHIGAN BY SUNRISE. THE FRONT
WILL THEN LEAVE CLOUDY AND COOLER CONDITIONS IN PLACE THROUGH
TUESDAY MORNING.

&&

.AVIATION...ISSUED 657 PM EDT MON SEP 29 2014

//DISCUSSION...

A STRONG COLD FRONT WILL MOVE THROUGH THE TERMINAL CORRIDOR DURING
THE EVENING. WIND SPEED WILL BE MODEST BUT THE WIND SHIFT WILL BE
SHARP TO THE NORTHWEST AND WILL BRING A DRAMATIC CHANGE IN
TEMPERATURE AND CLOUD CONDITIONS ALONG WITH A PATTERN OF SHOWERS AND
ISOLATED THUNDERSTORMS. RAIN WILL WILL ONLY LAST A FEW HOURS AT ANY
ONE STATION BUT CEILING WILL QUICKLY DROP TO MVFR AND THEN IFR FOR
THE BULK OF THE NIGHT. CEILING WILL GRADUALLY RISE DURING TUESDAY
BUT REMAIN LOCKED IN AT MVFR OVER COOL NORTH WIND.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET OVERNIGHT THROUGH
TUESDAY.

&&

.PREV DISCUSSION...ISSUED 344 PM EDT MON SEP 29 2014

SHORT TERM...THROUGH TONIGHT

QUIET AND WARM CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE
AFTERNOON AND INTO THE EVENING BEFORE AN APPROACHING COLD FRONT
USHERS IN BIG CHANGES FOR THE OVERNIGHT HOURS AND ESPECIALLY
TOMORROW.

UPPER TROUGH DROPPING FROM CANADA INTO NORTHERN MICHIGAN WILL DEEPEN
INTO A CLOSED LOW AS IT DROPS ACROSS LOWER MICHIGAN TONIGHT. AT THE
SURFACE...THIS WILL PUSH THE AREA OF SURFACE LOW PRESSURE CENTERED
SOUTH OF ALPENA SOUTHEAST ACROSS LAKE HURON AND INTO ONTARIO
TONIGHT. STRONG SURFACE COLD FRONT WILL TRAIL BEHIND THE
LOW...DROPPING THROUGH SOUTHEAST MICHIGAN THIS EVENING AND OVERNIGHT
(9PM THROUGH 6 AM). STILL LOOKING LIKE A GOOD SHOT FOR RAIN TONIGHT
ALONG THE FRONT WITH UPPER DIFFLUENCE AND GOOD UPPER HEIGHTS FALLS
POSITIONED ABOVE THE FRONT (SOME FGEN AS WELL)...AND AS A MODEST
SURGE OF THETA-E OCCURS. CONTINUE TO THINK THAT THE WINDOW FOR RAIN
SHOWERS AT ANY GIVEN LOCATION IS ONLY 2 TO 4 HOURS WIDE...WHICH
AGREES WELL WITH CURRENT RADAR PRESENTATION OVER NORTHERN MICHIGAN
AND WISCONSIN. (AREAS OF DRIZZLE MAY HOWEVER DEVELOP AFTER THE FRONT
SLIDES THROUGH AND DRIER AIR ALOFT WORKS IN.) SOME THUNDER WILL ALSO
BE POSSIBLE WITH STEEPENING MID-LEVEL LAPSE RATES AND MODEL
CROSS-SECTIONS SHOWING SOME CONVECTIVE INSTABILITY (MOSTLY ALOFT) AS
THE FRONT DROPS THROUGH. THERE WERE SOME THUNDER OVER THE U.P. LATE
LAST NIGHT ALONG THE FRONT.

TEMPERATURE GRADIENT ACROSS THE FRONT RIGHT NOW IS IMPRESSIVE...WITH
LOW 50S RIGHT NOW OVER NORTHERN LOWER MI AND UPPER 70S ACROSS
CENTRAL MI (40S IN THE U.P!). THE TEMPERATURE IN TRAVERSE CITY FELL
FROM 70 TO 58 DEGREES IN ONLY TWO HOURS THIS AFTERNOON AS THE FRONT
DROPPED ACROSS. OUR WARM TEMPS SHOULD HOLD THROUGH THE DAYLIGHT
HOURS BEFORE THE FRONT SLIDES THROUGH...RIGHT AS TEMPERATURES WOULD
COOL ANYHOW. WIND...CLOUDS...AND RAIN SHOULD PREVENT TEMPS FROM
GETTING TOO CHILLY OVERNIGHT...ESPECIALLY WITH BEST COLD AIR
ADVECTION HOLDING OFF UNTIL OVERNIGHT. MIN TEMPS ARE EXPECTED TO RUN
FROM THE MID 40S OVER THE THUMB/SAGINAW VALLEY TO THE MID 50S IN THE
DETROIT HEAT ISLAND.

LONG TERM...

564 DM CLOSED MID LEVEL CIRCULATION CENTERED OVER THE EASTERN
THUMB/SOUTHERN LAKE HURON TUESDAY MORNING WILL PIVOT TO THE EAST
THROUGH THE DAY...ALLOWING A DEEPER NORTHERLY FLOW TO TAKE HOLD
LOCALLY.  A SOLID PERIOD OF COLD AIR ADVECTION ALREADY UNDERWAY
POST-DAYBREAK WILL EASE BY MIDDAY...THE COLDEST CORE OF THIS AIRMASS
/850 MB TEMPS OF 4C/ CENTERING OVERHEAD BY AFTERNOON AND EVENING.
SUBSTANTIAL POST-FRONTAL LOW LEVEL MOISTURE WILL REMAIN TUCKED
BENEATH A BURGEONING INVERSION.  THIS COMBINED WITH STEEPENING LOW
LEVEL LAPSE RATES WILL ENSURE AN EXTENSIVE STRATUS FIELD REMAINS
PREVALENT THROUGHOUT THE DAY.  MOISTURE DEPTH MAY PROVE ADEQUATE
TOWARD GENERATING A FEW POCKETS OF LIGHT RAIN/DRIZZLE...STILL WORTHY
OF A SMALL POP MENTION.  GREATEST POTENTIAL WILL LIKELY EXIST ACROSS
THE THUMB UNDER SOME RENEWED CVA AS A TRAILING PIECE OF VORTICITY
WRAPS BACK AROUND THE EXITING LOW.  THE TIMING/STRENGTH OF THE
ADVECTIVE PROCESS AND THE LACK OF BETTER INSOLATION WILL CONFINE
HIGHS LARGELY IN THE MID AND UPPER 50S.

LOW LEVEL FLOW WILL VEER TO NORTHEASTERLY BY TUESDAY NIGHT AS THE
CENTER OF EXPANDING HIGH PRESSURE WORKS ACROSS ONTARIO.  THE
EXISTING CANOPY OF STRATUS WILL BUDGE LITTLE UNDER THIS SETUP...THE
ADDED CONTRIBUTION OFF LAKE HURON REINFORCING A SUFFICIENTLY
DEEP MOIST SUB-INVERSION LAYER.  LOWS UPPER 40S/LOWER 50S.

HIGH PRESSURE SETTLES IN FOR WEDNESDAY AS A NARROW UPPER RIDGE AXIS
CENTERS OVER THE REGION.  THIS WILL PROMPT A GRADUAL RELEASE OF THE
CLOUD COVER AS THE COMBINATION OF DAYTIME HEATING/MIXING AND
STRENGTHENING MID LEVEL SUBSIDENCE SHRINKS THE EXISTING MOIST LAYER.
A MODERATING AIR MASS GIVEN THE INCREASING THICKNESS FIELD AND SOME
LATE DAY INSOLATION WILL PROVIDE AN INCREMENTAL BOOST TO HIGHS.
850 MB TEMPERATURES ARE PROJECTED TO CLIMB BACK INTO THE 10C RANGE.
THIS WOULD SUPPORT READINGS WITHIN THE 65 TO 70F RANGE...ASSUMING
CLOUD COVER DOES NOT REMAIN PROBLEMATIC WELL INTO THE DAY.

TEMPERATURES WILL RECOVER NICELY FOR THE FIRST HALF OF THURSDAY
AHEAD OF AN APPROACHING COLD FRONT. EXPECT PROBABLY THE LAST RUN AT
80 FOR THE YEAR AS SOUTHERLY DRYING WINDS WILL TRY TO AID
INSOLATION. THE RAIN EVENT THURSDAY NIGHT WILL AVERAGE 0.5 TO 0.75
INCH OF QPF ACROSS THE CWA...WITH LOCALLY HIGHER AMOUNTS. EXPECT A
RAW WEEKEND AS TEMPERATURES DROP STEEPLY AND WINDS PICK UP TO GUST
OVER 25 MPH.

MARINE...

COLD FRONT MOVES THROUGH THE CENTRAL GREAT LAKES TONIGHT. NORTHERLY
WINDS WILL STRENGTHEN BEHIND THIS FRONT LATE TONIGHT AND EARLY
TUESDAY.  WINDS OF 15 TO 20 KNOTS WITH GUSTS TO 25 KNOTS ACROSS
CENTRAL AND SOUTHERN SECTIONS OF LAKE HURON.  THIS WILL PROMPT AN
INCREASE IN WAVE HEIGHTS...WITH APPROPRIATE SMALL CRAFT ADVISORIES
NOW IN PLACE.  WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH
PRESSURE BUILDS BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL
PERSIST WEDNESDAY AND THURSDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.

MI WATERS OF LAKE ERIE...NONE.

&&

$$

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


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








000
FXUS63 KDTX 292257
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
657 PM EDT MON SEP 29 2014

.AVIATION...

//DISCUSSION...

A STRONG COLD FRONT WILL MOVE THROUGH THE TERMINAL CORRIDOR DURING
THE EVENING. WIND SPEED WILL BE MODEST BUT THE WIND SHIFT WILL BE
SHARP TO THE NORTHWEST AND WILL BRING A DRAMATIC CHANGE IN
TEMPERATURE AND CLOUD CONDITIONS ALONG WITH A PATTERN OF SHOWERS AND
ISOLATED THUNDERSTORMS. RAIN WILL WILL ONLY LAST A FEW HOURS AT ANY
ONE STATION BUT CEILING WILL QUICKLY DROP TO MVFR AND THEN IFR FOR
THE BULK OF THE NIGHT. CEILING WILL GRADUALLY RISE DURING TUESDAY
BUT REMAIN LOCKED IN AT MVFR OVER COOL NORTH WIND.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET OVERNIGHT THROUGH
TUESDAY.

&&

.PREV DISCUSSION...ISSUED 344 PM EDT MON SEP 29 2014

SHORT TERM...THROUGH TONIGHT

QUIET AND WARM CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE
AFTERNOON AND INTO THE EVENING BEFORE AN APPROACHING COLD FRONT
USHERS IN BIG CHANGES FOR THE OVERNIGHT HOURS AND ESPECIALLY
TOMORROW.

UPPER TROUGH DROPPING FROM CANADA INTO NORTHERN MICHIGAN WILL DEEPEN
INTO A CLOSED LOW AS IT DROPS ACROSS LOWER MICHIGAN TONIGHT. AT THE
SURFACE...THIS WILL PUSH THE AREA OF SURFACE LOW PRESSURE CENTERED
SOUTH OF ALPENA SOUTHEAST ACROSS LAKE HURON AND INTO ONTARIO
TONIGHT. STRONG SURFACE COLD FRONT WILL TRAIL BEHIND THE
LOW...DROPPING THROUGH SOUTHEAST MICHIGAN THIS EVENING AND OVERNIGHT
(9PM THROUGH 6 AM). STILL LOOKING LIKE A GOOD SHOT FOR RAIN TONIGHT
ALONG THE FRONT WITH UPPER DIFFLUENCE AND GOOD UPPER HEIGHTS FALLS
POSITIONED ABOVE THE FRONT (SOME FGEN AS WELL)...AND AS A MODEST
SURGE OF THETA-E OCCURS. CONTINUE TO THINK THAT THE WINDOW FOR RAIN
SHOWERS AT ANY GIVEN LOCATION IS ONLY 2 TO 4 HOURS WIDE...WHICH
AGREES WELL WITH CURRENT RADAR PRESENTATION OVER NORTHERN MICHIGAN
AND WISCONSIN. (AREAS OF DRIZZLE MAY HOWEVER DEVELOP AFTER THE FRONT
SLIDES THROUGH AND DRIER AIR ALOFT WORKS IN.) SOME THUNDER WILL ALSO
BE POSSIBLE WITH STEEPENING MID-LEVEL LAPSE RATES AND MODEL
CROSS-SECTIONS SHOWING SOME CONVECTIVE INSTABILITY (MOSTLY ALOFT) AS
THE FRONT DROPS THROUGH. THERE WERE SOME THUNDER OVER THE U.P. LATE
LAST NIGHT ALONG THE FRONT.

TEMPERATURE GRADIENT ACROSS THE FRONT RIGHT NOW IS IMPRESSIVE...WITH
LOW 50S RIGHT NOW OVER NORTHERN LOWER MI AND UPPER 70S ACROSS
CENTRAL MI (40S IN THE U.P!). THE TEMPERATURE IN TRAVERSE CITY FELL
FROM 70 TO 58 DEGREES IN ONLY TWO HOURS THIS AFTERNOON AS THE FRONT
DROPPED ACROSS. OUR WARM TEMPS SHOULD HOLD THROUGH THE DAYLIGHT
HOURS BEFORE THE FRONT SLIDES THROUGH...RIGHT AS TEMPERATURES WOULD
COOL ANYHOW. WIND...CLOUDS...AND RAIN SHOULD PREVENT TEMPS FROM
GETTING TOO CHILLY OVERNIGHT...ESPECIALLY WITH BEST COLD AIR
ADVECTION HOLDING OFF UNTIL OVERNIGHT. MIN TEMPS ARE EXPECTED TO RUN
FROM THE MID 40S OVER THE THUMB/SAGINAW VALLEY TO THE MID 50S IN THE
DETROIT HEAT ISLAND.

LONG TERM...

564 DM CLOSED MID LEVEL CIRCULATION CENTERED OVER THE EASTERN
THUMB/SOUTHERN LAKE HURON TUESDAY MORNING WILL PIVOT TO THE EAST
THROUGH THE DAY...ALLOWING A DEEPER NORTHERLY FLOW TO TAKE HOLD
LOCALLY.  A SOLID PERIOD OF COLD AIR ADVECTION ALREADY UNDERWAY
POST-DAYBREAK WILL EASE BY MIDDAY...THE COLDEST CORE OF THIS AIRMASS
/850 MB TEMPS OF 4C/ CENTERING OVERHEAD BY AFTERNOON AND EVENING.
SUBSTANTIAL POST-FRONTAL LOW LEVEL MOISTURE WILL REMAIN TUCKED
BENEATH A BURGEONING INVERSION.  THIS COMBINED WITH STEEPENING LOW
LEVEL LAPSE RATES WILL ENSURE AN EXTENSIVE STRATUS FIELD REMAINS
PREVALENT THROUGHOUT THE DAY.  MOISTURE DEPTH MAY PROVE ADEQUATE
TOWARD GENERATING A FEW POCKETS OF LIGHT RAIN/DRIZZLE...STILL WORTHY
OF A SMALL POP MENTION.  GREATEST POTENTIAL WILL LIKELY EXIST ACROSS
THE THUMB UNDER SOME RENEWED CVA AS A TRAILING PIECE OF VORTICITY
WRAPS BACK AROUND THE EXITING LOW.  THE TIMING/STRENGTH OF THE
ADVECTIVE PROCESS AND THE LACK OF BETTER INSOLATION WILL CONFINE
HIGHS LARGELY IN THE MID AND UPPER 50S.

LOW LEVEL FLOW WILL VEER TO NORTHEASTERLY BY TUESDAY NIGHT AS THE
CENTER OF EXPANDING HIGH PRESSURE WORKS ACROSS ONTARIO.  THE
EXISTING CANOPY OF STRATUS WILL BUDGE LITTLE UNDER THIS SETUP...THE
ADDED CONTRIBUTION OFF LAKE HURON REINFORCING A SUFFICIENTLY
DEEP MOIST SUB-INVERSION LAYER.  LOWS UPPER 40S/LOWER 50S.

HIGH PRESSURE SETTLES IN FOR WEDNESDAY AS A NARROW UPPER RIDGE AXIS
CENTERS OVER THE REGION.  THIS WILL PROMPT A GRADUAL RELEASE OF THE
CLOUD COVER AS THE COMBINATION OF DAYTIME HEATING/MIXING AND
STRENGTHENING MID LEVEL SUBSIDENCE SHRINKS THE EXISTING MOIST LAYER.
A MODERATING AIR MASS GIVEN THE INCREASING THICKNESS FIELD AND SOME
LATE DAY INSOLATION WILL PROVIDE AN INCREMENTAL BOOST TO HIGHS.
850 MB TEMPERATURES ARE PROJECTED TO CLIMB BACK INTO THE 10C RANGE.
THIS WOULD SUPPORT READINGS WITHIN THE 65 TO 70F RANGE...ASSUMING
CLOUD COVER DOES NOT REMAIN PROBLEMATIC WELL INTO THE DAY.

TEMPERATURES WILL RECOVER NICELY FOR THE FIRST HALF OF THURSDAY
AHEAD OF AN APPROACHING COLD FRONT. EXPECT PROBABLY THE LAST RUN AT
80 FOR THE YEAR AS SOUTHERLY DRYING WINDS WILL TRY TO AID
INSOLATION. THE RAIN EVENT THURSDAY NIGHT WILL AVERAGE 0.5 TO 0.75
INCH OF QPF ACROSS THE CWA...WITH LOCALLY HIGHER AMOUNTS. EXPECT A
RAW WEEKEND AS TEMPERATURES DROP STEEPLY AND WINDS PICK UP TO GUST
OVER 25 MPH.

MARINE...

COLD FRONT MOVES THROUGH THE CENTRAL GREAT LAKES TONIGHT. NORTHERLY
WINDS WILL STRENGTHEN BEHIND THIS FRONT LATE TONIGHT AND EARLY
TUESDAY.  WINDS OF 15 TO 20 KNOTS WITH GUSTS TO 25 KNOTS ACROSS
CENTRAL AND SOUTHERN SECTIONS OF LAKE HURON.  THIS WILL PROMPT AN
INCREASE IN WAVE HEIGHTS...WITH APPROPRIATE SMALL CRAFT ADVISORIES
NOW IN PLACE.  WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH
PRESSURE BUILDS BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL
PERSIST WEDNESDAY AND THURSDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.

MI WATERS OF LAKE ERIE...NONE.

&&

$$

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


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








000
FXUS63 KDTX 292257
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
657 PM EDT MON SEP 29 2014

.AVIATION...

//DISCUSSION...

A STRONG COLD FRONT WILL MOVE THROUGH THE TERMINAL CORRIDOR DURING
THE EVENING. WIND SPEED WILL BE MODEST BUT THE WIND SHIFT WILL BE
SHARP TO THE NORTHWEST AND WILL BRING A DRAMATIC CHANGE IN
TEMPERATURE AND CLOUD CONDITIONS ALONG WITH A PATTERN OF SHOWERS AND
ISOLATED THUNDERSTORMS. RAIN WILL WILL ONLY LAST A FEW HOURS AT ANY
ONE STATION BUT CEILING WILL QUICKLY DROP TO MVFR AND THEN IFR FOR
THE BULK OF THE NIGHT. CEILING WILL GRADUALLY RISE DURING TUESDAY
BUT REMAIN LOCKED IN AT MVFR OVER COOL NORTH WIND.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET OVERNIGHT THROUGH
TUESDAY.

&&

.PREV DISCUSSION...ISSUED 344 PM EDT MON SEP 29 2014

SHORT TERM...THROUGH TONIGHT

QUIET AND WARM CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE
AFTERNOON AND INTO THE EVENING BEFORE AN APPROACHING COLD FRONT
USHERS IN BIG CHANGES FOR THE OVERNIGHT HOURS AND ESPECIALLY
TOMORROW.

UPPER TROUGH DROPPING FROM CANADA INTO NORTHERN MICHIGAN WILL DEEPEN
INTO A CLOSED LOW AS IT DROPS ACROSS LOWER MICHIGAN TONIGHT. AT THE
SURFACE...THIS WILL PUSH THE AREA OF SURFACE LOW PRESSURE CENTERED
SOUTH OF ALPENA SOUTHEAST ACROSS LAKE HURON AND INTO ONTARIO
TONIGHT. STRONG SURFACE COLD FRONT WILL TRAIL BEHIND THE
LOW...DROPPING THROUGH SOUTHEAST MICHIGAN THIS EVENING AND OVERNIGHT
(9PM THROUGH 6 AM). STILL LOOKING LIKE A GOOD SHOT FOR RAIN TONIGHT
ALONG THE FRONT WITH UPPER DIFFLUENCE AND GOOD UPPER HEIGHTS FALLS
POSITIONED ABOVE THE FRONT (SOME FGEN AS WELL)...AND AS A MODEST
SURGE OF THETA-E OCCURS. CONTINUE TO THINK THAT THE WINDOW FOR RAIN
SHOWERS AT ANY GIVEN LOCATION IS ONLY 2 TO 4 HOURS WIDE...WHICH
AGREES WELL WITH CURRENT RADAR PRESENTATION OVER NORTHERN MICHIGAN
AND WISCONSIN. (AREAS OF DRIZZLE MAY HOWEVER DEVELOP AFTER THE FRONT
SLIDES THROUGH AND DRIER AIR ALOFT WORKS IN.) SOME THUNDER WILL ALSO
BE POSSIBLE WITH STEEPENING MID-LEVEL LAPSE RATES AND MODEL
CROSS-SECTIONS SHOWING SOME CONVECTIVE INSTABILITY (MOSTLY ALOFT) AS
THE FRONT DROPS THROUGH. THERE WERE SOME THUNDER OVER THE U.P. LATE
LAST NIGHT ALONG THE FRONT.

TEMPERATURE GRADIENT ACROSS THE FRONT RIGHT NOW IS IMPRESSIVE...WITH
LOW 50S RIGHT NOW OVER NORTHERN LOWER MI AND UPPER 70S ACROSS
CENTRAL MI (40S IN THE U.P!). THE TEMPERATURE IN TRAVERSE CITY FELL
FROM 70 TO 58 DEGREES IN ONLY TWO HOURS THIS AFTERNOON AS THE FRONT
DROPPED ACROSS. OUR WARM TEMPS SHOULD HOLD THROUGH THE DAYLIGHT
HOURS BEFORE THE FRONT SLIDES THROUGH...RIGHT AS TEMPERATURES WOULD
COOL ANYHOW. WIND...CLOUDS...AND RAIN SHOULD PREVENT TEMPS FROM
GETTING TOO CHILLY OVERNIGHT...ESPECIALLY WITH BEST COLD AIR
ADVECTION HOLDING OFF UNTIL OVERNIGHT. MIN TEMPS ARE EXPECTED TO RUN
FROM THE MID 40S OVER THE THUMB/SAGINAW VALLEY TO THE MID 50S IN THE
DETROIT HEAT ISLAND.

LONG TERM...

564 DM CLOSED MID LEVEL CIRCULATION CENTERED OVER THE EASTERN
THUMB/SOUTHERN LAKE HURON TUESDAY MORNING WILL PIVOT TO THE EAST
THROUGH THE DAY...ALLOWING A DEEPER NORTHERLY FLOW TO TAKE HOLD
LOCALLY.  A SOLID PERIOD OF COLD AIR ADVECTION ALREADY UNDERWAY
POST-DAYBREAK WILL EASE BY MIDDAY...THE COLDEST CORE OF THIS AIRMASS
/850 MB TEMPS OF 4C/ CENTERING OVERHEAD BY AFTERNOON AND EVENING.
SUBSTANTIAL POST-FRONTAL LOW LEVEL MOISTURE WILL REMAIN TUCKED
BENEATH A BURGEONING INVERSION.  THIS COMBINED WITH STEEPENING LOW
LEVEL LAPSE RATES WILL ENSURE AN EXTENSIVE STRATUS FIELD REMAINS
PREVALENT THROUGHOUT THE DAY.  MOISTURE DEPTH MAY PROVE ADEQUATE
TOWARD GENERATING A FEW POCKETS OF LIGHT RAIN/DRIZZLE...STILL WORTHY
OF A SMALL POP MENTION.  GREATEST POTENTIAL WILL LIKELY EXIST ACROSS
THE THUMB UNDER SOME RENEWED CVA AS A TRAILING PIECE OF VORTICITY
WRAPS BACK AROUND THE EXITING LOW.  THE TIMING/STRENGTH OF THE
ADVECTIVE PROCESS AND THE LACK OF BETTER INSOLATION WILL CONFINE
HIGHS LARGELY IN THE MID AND UPPER 50S.

LOW LEVEL FLOW WILL VEER TO NORTHEASTERLY BY TUESDAY NIGHT AS THE
CENTER OF EXPANDING HIGH PRESSURE WORKS ACROSS ONTARIO.  THE
EXISTING CANOPY OF STRATUS WILL BUDGE LITTLE UNDER THIS SETUP...THE
ADDED CONTRIBUTION OFF LAKE HURON REINFORCING A SUFFICIENTLY
DEEP MOIST SUB-INVERSION LAYER.  LOWS UPPER 40S/LOWER 50S.

HIGH PRESSURE SETTLES IN FOR WEDNESDAY AS A NARROW UPPER RIDGE AXIS
CENTERS OVER THE REGION.  THIS WILL PROMPT A GRADUAL RELEASE OF THE
CLOUD COVER AS THE COMBINATION OF DAYTIME HEATING/MIXING AND
STRENGTHENING MID LEVEL SUBSIDENCE SHRINKS THE EXISTING MOIST LAYER.
A MODERATING AIR MASS GIVEN THE INCREASING THICKNESS FIELD AND SOME
LATE DAY INSOLATION WILL PROVIDE AN INCREMENTAL BOOST TO HIGHS.
850 MB TEMPERATURES ARE PROJECTED TO CLIMB BACK INTO THE 10C RANGE.
THIS WOULD SUPPORT READINGS WITHIN THE 65 TO 70F RANGE...ASSUMING
CLOUD COVER DOES NOT REMAIN PROBLEMATIC WELL INTO THE DAY.

TEMPERATURES WILL RECOVER NICELY FOR THE FIRST HALF OF THURSDAY
AHEAD OF AN APPROACHING COLD FRONT. EXPECT PROBABLY THE LAST RUN AT
80 FOR THE YEAR AS SOUTHERLY DRYING WINDS WILL TRY TO AID
INSOLATION. THE RAIN EVENT THURSDAY NIGHT WILL AVERAGE 0.5 TO 0.75
INCH OF QPF ACROSS THE CWA...WITH LOCALLY HIGHER AMOUNTS. EXPECT A
RAW WEEKEND AS TEMPERATURES DROP STEEPLY AND WINDS PICK UP TO GUST
OVER 25 MPH.

MARINE...

COLD FRONT MOVES THROUGH THE CENTRAL GREAT LAKES TONIGHT. NORTHERLY
WINDS WILL STRENGTHEN BEHIND THIS FRONT LATE TONIGHT AND EARLY
TUESDAY.  WINDS OF 15 TO 20 KNOTS WITH GUSTS TO 25 KNOTS ACROSS
CENTRAL AND SOUTHERN SECTIONS OF LAKE HURON.  THIS WILL PROMPT AN
INCREASE IN WAVE HEIGHTS...WITH APPROPRIATE SMALL CRAFT ADVISORIES
NOW IN PLACE.  WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH
PRESSURE BUILDS BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL
PERSIST WEDNESDAY AND THURSDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.

MI WATERS OF LAKE ERIE...NONE.

&&

$$

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


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









000
FXUS63 KDTX 291944
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
344 PM EDT MON SEP 29 2014

.SHORT TERM...THROUGH TONIGHT

QUIET AND WARM CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE
AFTERNOON AND INTO THE EVENING BEFORE AN APPROACHING COLD FRONT
USHERS IN BIG CHANGES FOR THE OVERNIGHT HOURS AND ESPECIALLY
TOMORROW.

UPPER TROUGH DROPPING FROM CANADA INTO NORTHERN MICHIGAN WILL DEEPEN
INTO A CLOSED LOW AS IT DROPS ACROSS LOWER MICHIGAN TONIGHT. AT THE
SURFACE...THIS WILL PUSH THE AREA OF SURFACE LOW PRESSURE CENTERED
SOUTH OF ALPENA SOUTHEAST ACROSS LAKE HURON AND INTO ONTARIO
TONIGHT. STRONG SURFACE COLD FRONT WILL TRAIL BEHIND THE
LOW...DROPPING THROUGH SOUTHEAST MICHIGAN THIS EVENING AND OVERNIGHT
(9PM THROUGH 6 AM). STILL LOOKING LIKE A GOOD SHOT FOR RAIN TONIGHT
ALONG THE FRONT WITH UPPER DIFFLUENCE AND GOOD UPPER HEIGHTS FALLS
POSITIONED ABOVE THE FRONT (SOME FGEN AS WELL)...AND AS A MODEST
SURGE OF THETA-E OCCURS. CONTINUE TO THINK THAT THE WINDOW FOR RAIN
SHOWERS AT ANY GIVEN LOCATION IS ONLY 2 TO 4 HOURS WIDE...WHICH
AGREES WELL WITH CURRENT RADAR PRESENTATION OVER NORTHERN MICHIGAN
AND WISCONSIN. (AREAS OF DRIZZLE MAY HOWEVER DEVELOP AFTER THE FRONT
SLIDES THROUGH AND DRIER AIR ALOFT WORKS IN.) SOME THUNDER WILL ALSO
BE POSSIBLE WITH STEEPENING MID-LEVEL LAPSE RATES AND MODEL
CROSS-SECTIONS SHOWING SOME CONVECTIVE INSTABILITY (MOSTLY ALOFT) AS
THE FRONT DROPS THROUGH. THERE WERE SOME THUNDER OVER THE U.P. LATE
LAST NIGHT ALONG THE FRONT.

TEMPERATURE GRADIENT ACROSS THE FRONT RIGHT NOW IS IMPRESSIVE...WITH
LOW 50S RIGHT NOW OVER NORTHERN LOWER MI AND UPPER 70S ACROSS
CENTRAL MI (40S IN THE U.P!). THE TEMPERATURE IN TRAVERSE CITY FELL
FROM 70 TO 58 DEGREES IN ONLY TWO HOURS THIS AFTERNOON AS THE FRONT
DROPPED ACROSS. OUR WARM TEMPS SHOULD HOLD THROUGH THE DAYLIGHT
HOURS BEFORE THE FRONT SLIDES THROUGH...RIGHT AS TEMPERATURES WOULD
COOL ANYHOW. WIND...CLOUDS...AND RAIN SHOULD PREVENT TEMPS FROM
GETTING TOO CHILLY OVERNIGHT...ESPECIALLY WITH BEST COLD AIR
ADVECTION HOLDING OFF UNTIL OVERNIGHT. MIN TEMPS ARE EXPECTED TO RUN
FROM THE MID 40S OVER THE THUMB/SAGINAW VALLEY TO THE MID 50S IN THE
DETROIT HEAT ISLAND.

&&

.LONG TERM...

564 DM CLOSED MID LEVEL CIRCULATION CENTERED OVER THE EASTERN
THUMB/SOUTHERN LAKE HURON TUESDAY MORNING WILL PIVOT TO THE EAST
THROUGH THE DAY...ALLOWING A DEEPER NORTHERLY FLOW TO TAKE HOLD
LOCALLY.  A SOLID PERIOD OF COLD AIR ADVECTION ALREADY UNDERWAY
POST-DAYBREAK WILL EASE BY MIDDAY...THE COLDEST CORE OF THIS AIRMASS
/850 MB TEMPS OF 4C/ CENTERING OVERHEAD BY AFTERNOON AND EVENING.
SUBSTANTIAL POST-FRONTAL LOW LEVEL MOISTURE WILL REMAIN TUCKED
BENEATH A BURGEONING INVERSION.  THIS COMBINED WITH STEEPENING LOW
LEVEL LAPSE RATES WILL ENSURE AN EXTENSIVE STRATUS FIELD REMAINS
PREVALENT THROUGHOUT THE DAY.  MOISTURE DEPTH MAY PROVE ADEQUATE
TOWARD GENERATING A FEW POCKETS OF LIGHT RAIN/DRIZZLE...STILL WORTHY
OF A SMALL POP MENTION.  GREATEST POTENTIAL WILL LIKELY EXIST ACROSS
THE THUMB UNDER SOME RENEWED CVA AS A TRAILING PIECE OF VORTICITY
WRAPS BACK AROUND THE EXITING LOW.  THE TIMING/STRENGTH OF THE
ADVECTIVE PROCESS AND THE LACK OF BETTER INSOLATION WILL CONFINE
HIGHS LARGELY IN THE MID AND UPPER 50S.

LOW LEVEL FLOW WILL VEER TO NORTHEASTERLY BY TUESDAY NIGHT AS THE
CENTER OF EXPANDING HIGH PRESSURE WORKS ACROSS ONTARIO.  THE
EXISTING CANOPY OF STRATUS WILL BUDGE LITTLE UNDER THIS SETUP...THE
ADDED CONTRIBUTION OFF LAKE HURON REINFORCING A SUFFICIENTLY
DEEP MOIST SUB-INVERSION LAYER.  LOWS UPPER 40S/LOWER 50S.

HIGH PRESSURE SETTLES IN FOR WEDNESDAY AS A NARROW UPPER RIDGE AXIS
CENTERS OVER THE REGION.  THIS WILL PROMPT A GRADUAL RELEASE OF THE
CLOUD COVER AS THE COMBINATION OF DAYTIME HEATING/MIXING AND
STRENGTHENING MID LEVEL SUBSIDENCE SHRINKS THE EXISTING MOIST LAYER.
A MODERATING AIR MASS GIVEN THE INCREASING THICKNESS FIELD AND SOME
LATE DAY INSOLATION WILL PROVIDE AN INCREMENTAL BOOST TO HIGHS.
850 MB TEMPERATURES ARE PROJECTED TO CLIMB BACK INTO THE 10C RANGE.
THIS WOULD SUPPORT READINGS WITHIN THE 65 TO 70F RANGE...ASSUMING
CLOUD COVER DOES NOT REMAIN PROBLEMATIC WELL INTO THE DAY.

TEMPERATURES WILL RECOVER NICELY FOR THE FIRST HALF OF THURSDAY
AHEAD OF AN APPROACHING COLD FRONT. EXPECT PROBABLY THE LAST RUN AT
80 FOR THE YEAR AS SOUTHERLY DRYING WINDS WILL TRY TO AID
INSOLATION. THE RAIN EVENT THURSDAY NIGHT WILL AVERAGE 0.5 TO 0.75
INCH OF QPF ACROSS THE CWA...WITH LOCALLY HIGHER AMOUNTS. EXPECT A
RAW WEEKEND AS TEMPERATURES DROP STEEPLY AND WINDS PICK UP TO GUST
OVER 25 MPH.

&&

.MARINE...

COLD FRONT MOVES THROUGH THE CENTRAL GREAT LAKES TONIGHT. NORTHERLY
WINDS WILL STRENGTHEN BEHIND THIS FRONT LATE TONIGHT AND EARLY
TUESDAY.  WINDS OF 15 TO 20 KNOTS WITH GUSTS TO 25 KNOTS ACROSS
CENTRAL AND SOUTHERN SECTIONS OF LAKE HURON.  THIS WILL PROMPT AN
INCREASE IN WAVE HEIGHTS...WITH APPROPRIATE SMALL CRAFT ADVISORIES
NOW IN PLACE.  WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH
PRESSURE BUILDS BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL
PERSIST WEDNESDAY AND THURSDAY.

&&

.AVIATION...ISSUED 132 PM EDT MON SEP 29 2014

//DISCUSSION...
LOW PRESSURE TRACKING ACROSS MICHIGAN WILL DRIVE A COLD FRONT DOWN
THROUGH SOUTHEAST MICHIGAN TERMINALS BETWEEN 01Z AND 08Z TONIGHT.
FORCING ASSOCIATED WITH THIS SYSTEM WILL BE CONFINED CLOSE TO THE
FRONT...AND WILL RESULT IN A 2-4 HOUR WINDOW CHARACTERIZED BY
RAIN...MVFR (POSSIBLY IFR) CEILINGS...AND AN ABRUPT WIND SHIFT TO
THE NORTHWEST. COLD AIR AND LOW-LEVEL MOISTURE WILL FILL IN BEHIND
THE FRONT...LOWERING CEILINGS TO IFR/LOW MVFR AND ALLOWING AREAS OF
DRIZZLE TO DEVELOP. CEILINGS WILL GRADUALLY RISE TOMORROW
AFTERNOON...BUT ARE EXPECTED TO REMAIN LOCKED IN AT MVFR.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE WITH CEILINGS BELOW 5000 FEET BETWEEN 07-18Z.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

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


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






000
FXUS63 KDTX 291944
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
344 PM EDT MON SEP 29 2014

.SHORT TERM...THROUGH TONIGHT

QUIET AND WARM CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE
AFTERNOON AND INTO THE EVENING BEFORE AN APPROACHING COLD FRONT
USHERS IN BIG CHANGES FOR THE OVERNIGHT HOURS AND ESPECIALLY
TOMORROW.

UPPER TROUGH DROPPING FROM CANADA INTO NORTHERN MICHIGAN WILL DEEPEN
INTO A CLOSED LOW AS IT DROPS ACROSS LOWER MICHIGAN TONIGHT. AT THE
SURFACE...THIS WILL PUSH THE AREA OF SURFACE LOW PRESSURE CENTERED
SOUTH OF ALPENA SOUTHEAST ACROSS LAKE HURON AND INTO ONTARIO
TONIGHT. STRONG SURFACE COLD FRONT WILL TRAIL BEHIND THE
LOW...DROPPING THROUGH SOUTHEAST MICHIGAN THIS EVENING AND OVERNIGHT
(9PM THROUGH 6 AM). STILL LOOKING LIKE A GOOD SHOT FOR RAIN TONIGHT
ALONG THE FRONT WITH UPPER DIFFLUENCE AND GOOD UPPER HEIGHTS FALLS
POSITIONED ABOVE THE FRONT (SOME FGEN AS WELL)...AND AS A MODEST
SURGE OF THETA-E OCCURS. CONTINUE TO THINK THAT THE WINDOW FOR RAIN
SHOWERS AT ANY GIVEN LOCATION IS ONLY 2 TO 4 HOURS WIDE...WHICH
AGREES WELL WITH CURRENT RADAR PRESENTATION OVER NORTHERN MICHIGAN
AND WISCONSIN. (AREAS OF DRIZZLE MAY HOWEVER DEVELOP AFTER THE FRONT
SLIDES THROUGH AND DRIER AIR ALOFT WORKS IN.) SOME THUNDER WILL ALSO
BE POSSIBLE WITH STEEPENING MID-LEVEL LAPSE RATES AND MODEL
CROSS-SECTIONS SHOWING SOME CONVECTIVE INSTABILITY (MOSTLY ALOFT) AS
THE FRONT DROPS THROUGH. THERE WERE SOME THUNDER OVER THE U.P. LATE
LAST NIGHT ALONG THE FRONT.

TEMPERATURE GRADIENT ACROSS THE FRONT RIGHT NOW IS IMPRESSIVE...WITH
LOW 50S RIGHT NOW OVER NORTHERN LOWER MI AND UPPER 70S ACROSS
CENTRAL MI (40S IN THE U.P!). THE TEMPERATURE IN TRAVERSE CITY FELL
FROM 70 TO 58 DEGREES IN ONLY TWO HOURS THIS AFTERNOON AS THE FRONT
DROPPED ACROSS. OUR WARM TEMPS SHOULD HOLD THROUGH THE DAYLIGHT
HOURS BEFORE THE FRONT SLIDES THROUGH...RIGHT AS TEMPERATURES WOULD
COOL ANYHOW. WIND...CLOUDS...AND RAIN SHOULD PREVENT TEMPS FROM
GETTING TOO CHILLY OVERNIGHT...ESPECIALLY WITH BEST COLD AIR
ADVECTION HOLDING OFF UNTIL OVERNIGHT. MIN TEMPS ARE EXPECTED TO RUN
FROM THE MID 40S OVER THE THUMB/SAGINAW VALLEY TO THE MID 50S IN THE
DETROIT HEAT ISLAND.

&&

.LONG TERM...

564 DM CLOSED MID LEVEL CIRCULATION CENTERED OVER THE EASTERN
THUMB/SOUTHERN LAKE HURON TUESDAY MORNING WILL PIVOT TO THE EAST
THROUGH THE DAY...ALLOWING A DEEPER NORTHERLY FLOW TO TAKE HOLD
LOCALLY.  A SOLID PERIOD OF COLD AIR ADVECTION ALREADY UNDERWAY
POST-DAYBREAK WILL EASE BY MIDDAY...THE COLDEST CORE OF THIS AIRMASS
/850 MB TEMPS OF 4C/ CENTERING OVERHEAD BY AFTERNOON AND EVENING.
SUBSTANTIAL POST-FRONTAL LOW LEVEL MOISTURE WILL REMAIN TUCKED
BENEATH A BURGEONING INVERSION.  THIS COMBINED WITH STEEPENING LOW
LEVEL LAPSE RATES WILL ENSURE AN EXTENSIVE STRATUS FIELD REMAINS
PREVALENT THROUGHOUT THE DAY.  MOISTURE DEPTH MAY PROVE ADEQUATE
TOWARD GENERATING A FEW POCKETS OF LIGHT RAIN/DRIZZLE...STILL WORTHY
OF A SMALL POP MENTION.  GREATEST POTENTIAL WILL LIKELY EXIST ACROSS
THE THUMB UNDER SOME RENEWED CVA AS A TRAILING PIECE OF VORTICITY
WRAPS BACK AROUND THE EXITING LOW.  THE TIMING/STRENGTH OF THE
ADVECTIVE PROCESS AND THE LACK OF BETTER INSOLATION WILL CONFINE
HIGHS LARGELY IN THE MID AND UPPER 50S.

LOW LEVEL FLOW WILL VEER TO NORTHEASTERLY BY TUESDAY NIGHT AS THE
CENTER OF EXPANDING HIGH PRESSURE WORKS ACROSS ONTARIO.  THE
EXISTING CANOPY OF STRATUS WILL BUDGE LITTLE UNDER THIS SETUP...THE
ADDED CONTRIBUTION OFF LAKE HURON REINFORCING A SUFFICIENTLY
DEEP MOIST SUB-INVERSION LAYER.  LOWS UPPER 40S/LOWER 50S.

HIGH PRESSURE SETTLES IN FOR WEDNESDAY AS A NARROW UPPER RIDGE AXIS
CENTERS OVER THE REGION.  THIS WILL PROMPT A GRADUAL RELEASE OF THE
CLOUD COVER AS THE COMBINATION OF DAYTIME HEATING/MIXING AND
STRENGTHENING MID LEVEL SUBSIDENCE SHRINKS THE EXISTING MOIST LAYER.
A MODERATING AIR MASS GIVEN THE INCREASING THICKNESS FIELD AND SOME
LATE DAY INSOLATION WILL PROVIDE AN INCREMENTAL BOOST TO HIGHS.
850 MB TEMPERATURES ARE PROJECTED TO CLIMB BACK INTO THE 10C RANGE.
THIS WOULD SUPPORT READINGS WITHIN THE 65 TO 70F RANGE...ASSUMING
CLOUD COVER DOES NOT REMAIN PROBLEMATIC WELL INTO THE DAY.

TEMPERATURES WILL RECOVER NICELY FOR THE FIRST HALF OF THURSDAY
AHEAD OF AN APPROACHING COLD FRONT. EXPECT PROBABLY THE LAST RUN AT
80 FOR THE YEAR AS SOUTHERLY DRYING WINDS WILL TRY TO AID
INSOLATION. THE RAIN EVENT THURSDAY NIGHT WILL AVERAGE 0.5 TO 0.75
INCH OF QPF ACROSS THE CWA...WITH LOCALLY HIGHER AMOUNTS. EXPECT A
RAW WEEKEND AS TEMPERATURES DROP STEEPLY AND WINDS PICK UP TO GUST
OVER 25 MPH.

&&

.MARINE...

COLD FRONT MOVES THROUGH THE CENTRAL GREAT LAKES TONIGHT. NORTHERLY
WINDS WILL STRENGTHEN BEHIND THIS FRONT LATE TONIGHT AND EARLY
TUESDAY.  WINDS OF 15 TO 20 KNOTS WITH GUSTS TO 25 KNOTS ACROSS
CENTRAL AND SOUTHERN SECTIONS OF LAKE HURON.  THIS WILL PROMPT AN
INCREASE IN WAVE HEIGHTS...WITH APPROPRIATE SMALL CRAFT ADVISORIES
NOW IN PLACE.  WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH
PRESSURE BUILDS BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL
PERSIST WEDNESDAY AND THURSDAY.

&&

.AVIATION...ISSUED 132 PM EDT MON SEP 29 2014

//DISCUSSION...
LOW PRESSURE TRACKING ACROSS MICHIGAN WILL DRIVE A COLD FRONT DOWN
THROUGH SOUTHEAST MICHIGAN TERMINALS BETWEEN 01Z AND 08Z TONIGHT.
FORCING ASSOCIATED WITH THIS SYSTEM WILL BE CONFINED CLOSE TO THE
FRONT...AND WILL RESULT IN A 2-4 HOUR WINDOW CHARACTERIZED BY
RAIN...MVFR (POSSIBLY IFR) CEILINGS...AND AN ABRUPT WIND SHIFT TO
THE NORTHWEST. COLD AIR AND LOW-LEVEL MOISTURE WILL FILL IN BEHIND
THE FRONT...LOWERING CEILINGS TO IFR/LOW MVFR AND ALLOWING AREAS OF
DRIZZLE TO DEVELOP. CEILINGS WILL GRADUALLY RISE TOMORROW
AFTERNOON...BUT ARE EXPECTED TO REMAIN LOCKED IN AT MVFR.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE WITH CEILINGS BELOW 5000 FEET BETWEEN 07-18Z.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

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


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





000
FXUS63 KDTX 291732
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
132 PM EDT MON SEP 29 2014


.AVIATION...

//DISCUSSION...
LOW PRESSURE TRACKING ACROSS MICHIGAN WILL DRIVE A COLD FRONT DOWN
THROUGH SOUTHEAST MICHIGAN TERMINALS BETWEEN 01Z AND 08Z TONIGHT.
FORCING ASSOCIATED WITH THIS SYSTEM WILL BE CONFINED CLOSE TO THE
FRONT...AND WILL RESULT IN A 2-4 HOUR WINDOW CHARACTERIZED BY
RAIN...MVFR (POSSIBLY IFR) CEILINGS...AND AN ABRUPT WIND SHIFT TO
THE NORTHWEST. COLD AIR AND LOW-LEVEL MOISTURE WILL FILL IN BEHIND
THE FRONT...LOWERING CEILINGS TO IFR/LOW MVFR AND ALLOWING AREAS OF
DRIZZLE TO DEVELOP. CEILINGS WILL GRADUALLY RISE TOMORROW
AFTERNOON...BUT ARE EXPECTED TO REMAIN LOCKED IN AT MVFR.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE WITH CEILINGS BELOW 5000 FEET BETWEEN 07-18Z.

&&

.PREV DISCUSSION...ISSUED 315 AM EDT MON SEP 29 2014

SHORT TERM...TODAY AND TONIGHT

A SURFACE COLD FRONT IS SHOWN STRETCHING FROM WRN NEBRASKA...ACROSS
THE UP OF MICHIGAN...AND INTO SRN QUEBEC AS OF 07Z. THERE IS A VERY
TIGHT LOW LEVEL BAROCLINIC ZONE ALONG THIS BOUNDARY AS EVIDENT BY
YESTERDAYS HIGHS IN THE 70S AND 80S SOUTH OF THE FRONT AND 40S AND
50S NORTH. RECENT SURFACE ANALYSES HAVE SHOWN THE DEVELOPMENT OF A
WEAK LOW ALONG THE BOUNDARY OVER CNTL UPPER MI. THIS SFC REFLECTION
HAS DEVELOPED WITHIN THE ENTRANCE REGION OF THE UPPER JET MAX AND
AHEAD OF A MID LEVEL TROUGH NOW ROTATING ACROSS NW ONTARIO AND SRN
MANITOBA.

THE WATER VAPOR LOOP HAS ALREADY BEEN SHOWING THIS MID LEVEL WAVE
AMPLIFYING AS IT TRACKS TOWARD THE E-SE. THIS IS IN SUPPORT OF THE
ENTIRE 00Z MODEL SUITE WHICH SHOW THIS WAVE UNDERGOING RAPID
DEEPENING AS IT TRACKS INTO NRN LOWER MI THIS EVENING...EVENTUALLY
EVOLVING INTO A COMPACT CLOSED MID LEVEL LOW OVER LAKE HURON BY 12Z
TUES. THE CORRESPONDING MID LEVEL HEIGHT FALLS WILL OVERSPREAD SE MI
TONIGHT ALONG WITH A NARROW AXIS OF STRONG DIFFERENTIAL CYCLONIC
VORTICITY ADVECTION. SE MI IS ALSO EXPECTED TO RESIDE IN THE
EXIT REGION OF A CYCLONICALLY CURVED UPPER JET MAX WITHIN THE BASE
OF THE UPPER TROUGH...ENHANCING LARGE SCALE UPPER DIVERGENCE. THE
00Z MODEL SUITE HAVE A REASONABLE HANDEL ON THE LOW-MID LEVEL
MOISTURE PLUME NOW STRETCHING ACROSS THE NRN GREAT LAKES...WHICH IS
FORECAST TO NARROW AS IT WORKS INTO SE MI TONIGHT. THE MOISTURE
LOOKS TO BE ENOUGH TO RESULT IN A BRIEF PERIOD /2 TO 4 HOURS/ OF
SHOWERS CONSIDERING THE STRONG LARGE SCALE ASCENT. THIS BRIEF WINDOW
WHEN THE FORCING AND MOISTURE WILL ALIGN IS EXPECTED TO OCCUR ALONG
AND JUST BEHIND THE SFC FRONT WHICH THE HI RES SOLUTIONS SUGGEST
WILL BE DRIVEN INTO THE TRI CITIES AROUND 00Z AND ACROSS METRO
DETROIT AROUND 06Z. MODEL CROSS SECTIONS SHOW SOME WEAK CONVECTIVE
INSTABILITY AS RAPID COOLING ALOFT STEEPENS MID LEVEL LAPSE RATES.
IN LIGHT OF THE BRIEF YET INTENSE PERIOD OF LARGE SCALE
ASCENT...SOME ISOLATED THUNDERSTORMS CAN NOT BE RULED OUT.

LIKE THE LAST SEVERAL MORNINGS...THERE WILL BE SOME FOG AROUND TO
START THE DAY. MODEL SOUNDINGS AND THE RECENT IR SUGGEST THIS
MOISTURE IS QUITE SHALLOW AND WILL MIX OUT FAIRLY QUICKLY THIS
MORNING. THE LACK OF MUCH CLOUD COVER AHEAD OF THE COLD FRONT AND
SUBTLE LOW LEVEL WARM AIR ADVECTION IN THE PREFRONTAL AIRMASS WILL
BOOST DAYTIME HIGHS TO THE UPPER 70S/AROUND 80. STRONG LOW LEVEL
COLD AIR ADVECTION TONIGHT WILL RAPIDLY DROP TEMPS INTO THE 40S
FOLLOWING FROPA. CHANCE POPS WILL BE CONTINUED THROUGH DAYBREAK TUES
AS EXTENSIVE POST FRONTAL STRATUS WITHIN THE DEEPENING INVERSION MAY
RESULT IN SOME DRIZZLE.

LONG TERM...

MUCH COOLER WEATHER ON TUESDAY...AS 500 MB LOW/COLD POOL (0 C AT 700
MB) SLOWLY EXITS THE CENTRAL GREAT LAKES REGION. STEEP LOW LEVEL
LAPSE RATES...COUPLED WITH NORTHERLY FLOW OFF LAKE HURON SHOULD
ASSURE CLOUDY SKIES ACROSS SOUTHEAST MICHIGAN...WITH EVEN ENOUGH LOW
LEVEL SATURATION/CAPE TO POTENTIALLY CAUSE A FEW LIGHT
SHOWERS/SPRINKLES. PRONOUNCED SUBSIDENCE INVERSION IN PLACE TUESDAY
NIGHT EXPECTED TO TRAP LOW LEVEL MOISTURE TO MAINTAIN MOSTLY CLOUDY
SKIES THROUGH THE NIGHT. WITH SURFACE HIGH/RIDGE IN PLACE AND UPPER
LEVEL RIDGE OVERHEAD ON WEDNESDAY...MAY PROVE DIFFICULT TO MIX OUT
THE LOW LEVEL MOISTURE/CLOUDS...ESPECIALLY OVER THE THUMB REGION.

UPPER LEVEL LOW OVER THE GREAT BASIN EARLY THIS MORNING WILL BE
INFUSED BY UPPER LEVEL LOW/COLD POOL OFF THE BRITISH COLUMBIA
COAST...LEADING TO LONGWAVE TROUGH ENCOMPASSING WESTERN NORTH
AMERICA TUESDAY-WEDNESDAY. GOOD MOISTURE ADVECTION WILL TRANSLATE
NORTHEAST INTO THE GREAT LAKES REGION AS WE HEAD INTO
THURSDAY...WITH PW VALUES RISING ABOVE 1.5 INCHES. TIMING OF THE
850-700 MB THETA-E RIDGE AXIS AHEAD OF THE COLD FRONT LOOKS TO BE
THURSDAY EVENING...SUPPORTING HIGH LIKELY POPS AS AGRESSIVE HEIGHT
FALLS TAKE OVER TO END THE WORK WEEK. THERE IS EVEN A SLIGHT
CHANCE OF THUNDERSTORMS WITH THE COLD FRONT..AS SHOWALTER INDEX
PROGGED TO GO SLIGHTLY BELOW ZERO THURSDAY EVENING...PER 00Z EURO.

MARINE...

A COLD FRONT WILL SLIDE THROUGH THE CENTRAL GREAT LAKES TONIGHT.
SOLID NORTH WINDS OF 15 TO 25 KNOTS WILL FOLLOW BEHIND THE COLD
FRONT INTO TUESDAY MORNING. WITH THE COLD ADVECTION AND STRONGER
WINDS...WAVES WILL BUILD IN EXCESS OF 4 FEET OVER CENTRAL AND
SOUTHERN LAKE HURON...AND SMALL CRAFT ADVISORIES HAVE BEEN ISSUED.
WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH PRESSURE BUILDS
BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL PERSIST
WEDNESDAY AND THURSDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

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


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






000
FXUS63 KDTX 291100
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
700 AM EDT MON SEP 29 2014


.AVIATION...

//DISCUSSION...

MORNING FOG REMAINS SHALLOW /ESPECIALLY AT THE TERMINALS/. SO ANY
VSBY RESTRICTS PAST 12Z THIS MORNING SHOULD BE SHORT LIVED. MAINLY
CLEAR SKIES AND LIGHT WINDS WILL THEN PREVAIL THROUGH THE REMAINDER
OF THE MORNING AND AFTERNOON UNDER LINGERING HIGH PRESSURE OVER SRN
MI. A COLD FRONT NOW ENTERING NORTHERN LAKE MI IS FORECAST TO TRACK
ACROSS MBS BY 01 OR 02Z...THEN MOVE SE OF METRO DETROIT SHORTLY
AFTER 06Z TONIGHT. THIS FRONT WILL BE MARKED BY AN ABRUPT SHIFT IN
THE WIND TO THE N-NW...A TWO TO FOUR HOUR PERIOD OF SHOWERS AND
RAPIDLY LOWERING CEILINGS. MODEL SOUNDINGS AND UPSTREAM OBSERVATIONS
WOULD SUGGEST LOW END MVFR AND IFR POST FRONTAL STATUS TONIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS DROPPING BELOW 5000 FT AFTER 06Z.

&&

.PREV DISCUSSION...ISSUED 315 AM EDT MON SEP 29 2014

SHORT TERM...TODAY AND TONIGHT

A SURFACE COLD FRONT IS SHOWN STRETCHING FROM WRN NEBRASKA...ACROSS
THE UP OF MICHIGAN...AND INTO SRN QUEBEC AS OF 07Z. THERE IS A VERY
TIGHT LOW LEVEL BAROCLINIC ZONE ALONG THIS BOUNDARY AS EVIDENT BY
YESTERDAYS HIGHS IN THE 70S AND 80S SOUTH OF THE FRONT AND 40S AND
50S NORTH. RECENT SURFACE ANALYSES HAVE SHOWN THE DEVELOPMENT OF A
WEAK LOW ALONG THE BOUNDARY OVER CNTL UPPER MI. THIS SFC REFLECTION
HAS DEVELOPED WITHIN THE ENTRANCE REGION OF THE UPPER JET MAX AND
AHEAD OF A MID LEVEL TROUGH NOW ROTATING ACROSS NW ONTARIO AND SRN
MANITOBA.

THE WATER VAPOR LOOP HAS ALREADY BEEN SHOWING THIS MID LEVEL WAVE
AMPLIFYING AS IT TRACKS TOWARD THE E-SE. THIS IS IN SUPPORT OF THE
ENTIRE 00Z MODEL SUITE WHICH SHOW THIS WAVE UNDERGOING RAPID
DEEPENING AS IT TRACKS INTO NRN LOWER MI THIS EVENING...EVENTUALLY
EVOLVING INTO A COMPACT CLOSED MID LEVEL LOW OVER LAKE HURON BY 12Z
TUES. THE CORRESPONDING MID LEVEL HEIGHT FALLS WILL OVERSPREAD SE MI
TONIGHT ALONG WITH A NARROW AXIS OF STRONG DIFFERENTIAL CYCLONIC
VORTICITY ADVECTION. SE MI IS ALSO EXPECTED TO RESIDE IN THE
EXIT REGION OF A CYCLONICALLY CURVED UPPER JET MAX WITHIN THE BASE
OF THE UPPER TROUGH...ENHANCING LARGE SCALE UPPER DIVERGENCE. THE
00Z MODEL SUITE HAVE A REASONABLE HANDEL ON THE LOW-MID LEVEL
MOISTURE PLUME NOW STRETCHING ACROSS THE NRN GREAT LAKES...WHICH IS
FORECAST TO NARROW AS IT WORKS INTO SE MI TONIGHT. THE MOISTURE
LOOKS TO BE ENOUGH TO RESULT IN A BRIEF PERIOD /2 TO 4 HOURS/ OF
SHOWERS CONSIDERING THE STRONG LARGE SCALE ASCENT. THIS BRIEF WINDOW
WHEN THE FORCING AND MOISTURE WILL ALIGN IS EXPECTED TO OCCUR ALONG
AND JUST BEHIND THE SFC FRONT WHICH THE HI RES SOLUTIONS SUGGEST
WILL BE DRIVEN INTO THE TRI CITIES AROUND 00Z AND ACROSS METRO
DETROIT AROUND 06Z. MODEL CROSS SECTIONS SHOW SOME WEAK CONVECTIVE
INSTABILITY AS RAPID COOLING ALOFT STEEPENS MID LEVEL LAPSE RATES.
IN LIGHT OF THE BRIEF YET INTENSE PERIOD OF LARGE SCALE
ASCENT...SOME ISOLATED THUNDERSTORMS CAN NOT BE RULED OUT.

LIKE THE LAST SEVERAL MORNINGS...THERE WILL BE SOME FOG AROUND TO
START THE DAY. MODEL SOUNDINGS AND THE RECENT IR SUGGEST THIS
MOISTURE IS QUITE SHALLOW AND WILL MIX OUT FAIRLY QUICKLY THIS
MORNING. THE LACK OF MUCH CLOUD COVER AHEAD OF THE COLD FRONT AND
SUBTLE LOW LEVEL WARM AIR ADVECTION IN THE PREFRONTAL AIRMASS WILL
BOOST DAYTIME HIGHS TO THE UPPER 70S/AROUND 80. STRONG LOW LEVEL
COLD AIR ADVECTION TONIGHT WILL RAPIDLY DROP TEMPS INTO THE 40S
FOLLOWING FROPA. CHANCE POPS WILL BE CONTINUED THROUGH DAYBREAK TUES
AS EXTENSIVE POST FRONTAL STRATUS WITHIN THE DEEPENING INVERSION MAY
RESULT IN SOME DRIZZLE.

LONG TERM...

MUCH COOLER WEATHER ON TUESDAY...AS 500 MB LOW/COLD POOL (0 C AT 700
MB) SLOWLY EXITS THE CENTRAL GREAT LAKES REGION. STEEP LOW LEVEL
LAPSE RATES...COUPLED WITH NORTHERLY FLOW OFF LAKE HURON SHOULD
ASSURE CLOUDY SKIES ACROSS SOUTHEAST MICHIGAN...WITH EVEN ENOUGH LOW
LEVEL SATURATION/CAPE TO POTENTIALLY CAUSE A FEW LIGHT
SHOWERS/SPRINKLES. PRONOUNCED SUBSIDENCE INVERSION IN PLACE TUESDAY
NIGHT EXPECTED TO TRAP LOW LEVEL MOISTURE TO MAINTAIN MOSTLY CLOUDY
SKIES THROUGH THE NIGHT. WITH SURFACE HIGH/RIDGE IN PLACE AND UPPER
LEVEL RIDGE OVERHEAD ON WEDNESDAY...MAY PROVE DIFFICULT TO MIX OUT
THE LOW LEVEL MOISTURE/CLOUDS...ESPECIALLY OVER THE THUMB REGION.

UPPER LEVEL LOW OVER THE GREAT BASIN EARLY THIS MORNING WILL BE
INFUSED BY UPPER LEVEL LOW/COLD POOL OFF THE BRITISH COLUMBIA
COAST...LEADING TO LONGWAVE TROUGH ENCOMPASSING WESTERN NORTH
AMERICA TUESDAY-WEDNESDAY. GOOD MOISTURE ADVECTION WILL TRANSLATE
NORTHEAST INTO THE GREAT LAKES REGION AS WE HEAD INTO
THURSDAY...WITH PW VALUES RISING ABOVE 1.5 INCHES. TIMING OF THE
850-700 MB THETA-E RIDGE AXIS AHEAD OF THE COLD FRONT LOOKS TO BE
THURSDAY EVENING...SUPPORTING HIGH LIKELY POPS AS AGRESSIVE HEIGHT
FALLS TAKE OVER TO END THE WORK WEEK. THERE IS EVEN A SLIGHT
CHANCE OF THUNDERSTORMS WITH THE COLD FRONT..AS SHOWALTER INDEX
PROGGED TO GO SLIGHTLY BELOW ZERO THURSDAY EVENING...PER 00Z EURO.

MARINE...

A COLD FRONT WILL SLIDE THROUGH THE CENTRAL GREAT LAKES TONIGHT.
SOLID NORTH WINDS OF 15 TO 25 KNOTS WILL FOLLOW BEHIND THE COLD
FRONT INTO TUESDAY MORNING. WITH THE COLD ADVECTION AND STRONGER
WINDS...WAVES WILL BUILD IN EXCESS OF 4 FEET OVER CENTRAL AND
SOUTHERN LAKE HURON...AND SMALL CRAFT ADVISORIES HAVE BEEN ISSUED.
WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH PRESSURE BUILDS
BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL PERSIST
WEDNESDAY AND THURSDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....SC
SHORT TERM...SC
LONG TERM....SF
MARINE.......SF


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








000
FXUS63 KDTX 291100
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
700 AM EDT MON SEP 29 2014


.AVIATION...

//DISCUSSION...

MORNING FOG REMAINS SHALLOW /ESPECIALLY AT THE TERMINALS/. SO ANY
VSBY RESTRICTS PAST 12Z THIS MORNING SHOULD BE SHORT LIVED. MAINLY
CLEAR SKIES AND LIGHT WINDS WILL THEN PREVAIL THROUGH THE REMAINDER
OF THE MORNING AND AFTERNOON UNDER LINGERING HIGH PRESSURE OVER SRN
MI. A COLD FRONT NOW ENTERING NORTHERN LAKE MI IS FORECAST TO TRACK
ACROSS MBS BY 01 OR 02Z...THEN MOVE SE OF METRO DETROIT SHORTLY
AFTER 06Z TONIGHT. THIS FRONT WILL BE MARKED BY AN ABRUPT SHIFT IN
THE WIND TO THE N-NW...A TWO TO FOUR HOUR PERIOD OF SHOWERS AND
RAPIDLY LOWERING CEILINGS. MODEL SOUNDINGS AND UPSTREAM OBSERVATIONS
WOULD SUGGEST LOW END MVFR AND IFR POST FRONTAL STATUS TONIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS DROPPING BELOW 5000 FT AFTER 06Z.

&&

.PREV DISCUSSION...ISSUED 315 AM EDT MON SEP 29 2014

SHORT TERM...TODAY AND TONIGHT

A SURFACE COLD FRONT IS SHOWN STRETCHING FROM WRN NEBRASKA...ACROSS
THE UP OF MICHIGAN...AND INTO SRN QUEBEC AS OF 07Z. THERE IS A VERY
TIGHT LOW LEVEL BAROCLINIC ZONE ALONG THIS BOUNDARY AS EVIDENT BY
YESTERDAYS HIGHS IN THE 70S AND 80S SOUTH OF THE FRONT AND 40S AND
50S NORTH. RECENT SURFACE ANALYSES HAVE SHOWN THE DEVELOPMENT OF A
WEAK LOW ALONG THE BOUNDARY OVER CNTL UPPER MI. THIS SFC REFLECTION
HAS DEVELOPED WITHIN THE ENTRANCE REGION OF THE UPPER JET MAX AND
AHEAD OF A MID LEVEL TROUGH NOW ROTATING ACROSS NW ONTARIO AND SRN
MANITOBA.

THE WATER VAPOR LOOP HAS ALREADY BEEN SHOWING THIS MID LEVEL WAVE
AMPLIFYING AS IT TRACKS TOWARD THE E-SE. THIS IS IN SUPPORT OF THE
ENTIRE 00Z MODEL SUITE WHICH SHOW THIS WAVE UNDERGOING RAPID
DEEPENING AS IT TRACKS INTO NRN LOWER MI THIS EVENING...EVENTUALLY
EVOLVING INTO A COMPACT CLOSED MID LEVEL LOW OVER LAKE HURON BY 12Z
TUES. THE CORRESPONDING MID LEVEL HEIGHT FALLS WILL OVERSPREAD SE MI
TONIGHT ALONG WITH A NARROW AXIS OF STRONG DIFFERENTIAL CYCLONIC
VORTICITY ADVECTION. SE MI IS ALSO EXPECTED TO RESIDE IN THE
EXIT REGION OF A CYCLONICALLY CURVED UPPER JET MAX WITHIN THE BASE
OF THE UPPER TROUGH...ENHANCING LARGE SCALE UPPER DIVERGENCE. THE
00Z MODEL SUITE HAVE A REASONABLE HANDEL ON THE LOW-MID LEVEL
MOISTURE PLUME NOW STRETCHING ACROSS THE NRN GREAT LAKES...WHICH IS
FORECAST TO NARROW AS IT WORKS INTO SE MI TONIGHT. THE MOISTURE
LOOKS TO BE ENOUGH TO RESULT IN A BRIEF PERIOD /2 TO 4 HOURS/ OF
SHOWERS CONSIDERING THE STRONG LARGE SCALE ASCENT. THIS BRIEF WINDOW
WHEN THE FORCING AND MOISTURE WILL ALIGN IS EXPECTED TO OCCUR ALONG
AND JUST BEHIND THE SFC FRONT WHICH THE HI RES SOLUTIONS SUGGEST
WILL BE DRIVEN INTO THE TRI CITIES AROUND 00Z AND ACROSS METRO
DETROIT AROUND 06Z. MODEL CROSS SECTIONS SHOW SOME WEAK CONVECTIVE
INSTABILITY AS RAPID COOLING ALOFT STEEPENS MID LEVEL LAPSE RATES.
IN LIGHT OF THE BRIEF YET INTENSE PERIOD OF LARGE SCALE
ASCENT...SOME ISOLATED THUNDERSTORMS CAN NOT BE RULED OUT.

LIKE THE LAST SEVERAL MORNINGS...THERE WILL BE SOME FOG AROUND TO
START THE DAY. MODEL SOUNDINGS AND THE RECENT IR SUGGEST THIS
MOISTURE IS QUITE SHALLOW AND WILL MIX OUT FAIRLY QUICKLY THIS
MORNING. THE LACK OF MUCH CLOUD COVER AHEAD OF THE COLD FRONT AND
SUBTLE LOW LEVEL WARM AIR ADVECTION IN THE PREFRONTAL AIRMASS WILL
BOOST DAYTIME HIGHS TO THE UPPER 70S/AROUND 80. STRONG LOW LEVEL
COLD AIR ADVECTION TONIGHT WILL RAPIDLY DROP TEMPS INTO THE 40S
FOLLOWING FROPA. CHANCE POPS WILL BE CONTINUED THROUGH DAYBREAK TUES
AS EXTENSIVE POST FRONTAL STRATUS WITHIN THE DEEPENING INVERSION MAY
RESULT IN SOME DRIZZLE.

LONG TERM...

MUCH COOLER WEATHER ON TUESDAY...AS 500 MB LOW/COLD POOL (0 C AT 700
MB) SLOWLY EXITS THE CENTRAL GREAT LAKES REGION. STEEP LOW LEVEL
LAPSE RATES...COUPLED WITH NORTHERLY FLOW OFF LAKE HURON SHOULD
ASSURE CLOUDY SKIES ACROSS SOUTHEAST MICHIGAN...WITH EVEN ENOUGH LOW
LEVEL SATURATION/CAPE TO POTENTIALLY CAUSE A FEW LIGHT
SHOWERS/SPRINKLES. PRONOUNCED SUBSIDENCE INVERSION IN PLACE TUESDAY
NIGHT EXPECTED TO TRAP LOW LEVEL MOISTURE TO MAINTAIN MOSTLY CLOUDY
SKIES THROUGH THE NIGHT. WITH SURFACE HIGH/RIDGE IN PLACE AND UPPER
LEVEL RIDGE OVERHEAD ON WEDNESDAY...MAY PROVE DIFFICULT TO MIX OUT
THE LOW LEVEL MOISTURE/CLOUDS...ESPECIALLY OVER THE THUMB REGION.

UPPER LEVEL LOW OVER THE GREAT BASIN EARLY THIS MORNING WILL BE
INFUSED BY UPPER LEVEL LOW/COLD POOL OFF THE BRITISH COLUMBIA
COAST...LEADING TO LONGWAVE TROUGH ENCOMPASSING WESTERN NORTH
AMERICA TUESDAY-WEDNESDAY. GOOD MOISTURE ADVECTION WILL TRANSLATE
NORTHEAST INTO THE GREAT LAKES REGION AS WE HEAD INTO
THURSDAY...WITH PW VALUES RISING ABOVE 1.5 INCHES. TIMING OF THE
850-700 MB THETA-E RIDGE AXIS AHEAD OF THE COLD FRONT LOOKS TO BE
THURSDAY EVENING...SUPPORTING HIGH LIKELY POPS AS AGRESSIVE HEIGHT
FALLS TAKE OVER TO END THE WORK WEEK. THERE IS EVEN A SLIGHT
CHANCE OF THUNDERSTORMS WITH THE COLD FRONT..AS SHOWALTER INDEX
PROGGED TO GO SLIGHTLY BELOW ZERO THURSDAY EVENING...PER 00Z EURO.

MARINE...

A COLD FRONT WILL SLIDE THROUGH THE CENTRAL GREAT LAKES TONIGHT.
SOLID NORTH WINDS OF 15 TO 25 KNOTS WILL FOLLOW BEHIND THE COLD
FRONT INTO TUESDAY MORNING. WITH THE COLD ADVECTION AND STRONGER
WINDS...WAVES WILL BUILD IN EXCESS OF 4 FEET OVER CENTRAL AND
SOUTHERN LAKE HURON...AND SMALL CRAFT ADVISORIES HAVE BEEN ISSUED.
WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH PRESSURE BUILDS
BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL PERSIST
WEDNESDAY AND THURSDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....SC
SHORT TERM...SC
LONG TERM....SF
MARINE.......SF


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







000
FXUS63 KDTX 290715
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
315 AM EDT MON SEP 29 2014

.SHORT TERM...TODAY AND TONIGHT

A SURFACE COLD FRONT IS SHOWN STRETCHING FROM WRN NEBRASKA...ACROSS
THE UP OF MICHIGAN...AND INTO SRN QUEBEC AS OF 07Z. THERE IS A VERY
TIGHT LOW LEVEL BAROCLINIC ZONE ALONG THIS BOUNDARY AS EVIDENT BY
YESTERDAYS HIGHS IN THE 70S AND 80S SOUTH OF THE FRONT AND 40S AND
50S NORTH. RECENT SURFACE ANALYSES HAVE SHOWN THE DEVELOPMENT OF A
WEAK LOW ALONG THE BOUNDARY OVER CNTL UPPER MI. THIS SFC REFLECTION
HAS DEVELOPED WITHIN THE ENTRANCE REGION OF THE UPPER JET MAX AND
AHEAD OF A MID LEVEL TROUGH NOW ROTATING ACROSS NW ONTARIO AND SRN
MANITOBA.

THE WATER VAPOR LOOP HAS ALREADY BEEN SHOWING THIS MID LEVEL WAVE
AMPLIFYING AS IT TRACKS TOWARD THE E-SE. THIS IS IN SUPPORT OF THE
ENTIRE 00Z MODEL SUITE WHICH SHOW THIS WAVE UNDERGOING RAPID
DEEPENING AS IT TRACKS INTO NRN LOWER MI THIS EVENING...EVENTUALLY
EVOLVING INTO A COMPACT CLOSED MID LEVEL LOW OVER LAKE HURON BY 12Z
TUES. THE CORRESPONDING MID LEVEL HEIGHT FALLS WILL OVERSPREAD SE MI
TONIGHT ALONG WITH A NARROW AXIS OF STRONG DIFFERENTIAL CYCLONIC
VORTICITY ADVECTION. SE MI IS ALSO EXPECTED TO RESIDE IN THE
EXIT REGION OF A CYCLONICALLY CURVED UPPER JET MAX WITHIN THE BASE
OF THE UPPER TROUGH...ENHANCING LARGE SCALE UPPER DIVERGENCE. THE
00Z MODEL SUITE HAVE A REASONABLE HANDEL ON THE LOW-MID LEVEL
MOISTURE PLUME NOW STRETCHING ACROSS THE NRN GREAT LAKES...WHICH IS
FORECAST TO NARROW AS IT WORKS INTO SE MI TONIGHT. THE MOISTURE
LOOKS TO BE ENOUGH TO RESULT IN A BRIEF PERIOD /2 TO 4 HOURS/ OF
SHOWERS CONSIDERING THE STRONG LARGE SCALE ASCENT. THIS BRIEF WINDOW
WHEN THE FORCING AND MOISTURE WILL ALIGN IS EXPECTED TO OCCUR ALONG
AND JUST BEHIND THE SFC FRONT WHICH THE HI RES SOLUTIONS SUGGEST
WILL BE DRIVEN INTO THE TRI CITIES AROUND 00Z AND ACROSS METRO
DETROIT AROUND 06Z. MODEL CROSS SECTIONS SHOW SOME WEAK CONVECTIVE
INSTABILITY AS RAPID COOLING ALOFT STEEPENS MID LEVEL LAPSE RATES.
IN LIGHT OF THE BRIEF YET INTENSE PERIOD OF LARGE SCALE
ASCENT...SOME ISOLATED THUNDERSTORMS CAN NOT BE RULED OUT.

LIKE THE LAST SEVERAL MORNINGS...THERE WILL BE SOME FOG AROUND TO
START THE DAY. MODEL SOUNDINGS AND THE RECENT IR SUGGEST THIS
MOISTURE IS QUITE SHALLOW AND WILL MIX OUT FAIRLY QUICKLY THIS
MORNING. THE LACK OF MUCH CLOUD COVER AHEAD OF THE COLD FRONT AND
SUBTLE LOW LEVEL WARM AIR ADVECTION IN THE PREFRONTAL AIRMASS WILL
BOOST DAYTIME HIGHS TO THE UPPER 70S/AROUND 80. STRONG LOW LEVEL
COLD AIR ADVECTION TONIGHT WILL RAPIDLY DROP TEMPS INTO THE 40S
FOLLOWING FROPA. CHANCE POPS WILL BE CONTINUED THROUGH DAYBREAK TUES
AS EXTENSIVE POST FRONTAL STRATUS WITHIN THE DEEPENING INVERSION MAY
RESULT IN SOME DRIZZLE.

&&

.LONG TERM...

MUCH COOLER WEATHER ON TUESDAY...AS 500 MB LOW/COLD POOL (0 C AT 700
MB) SLOWLY EXITS THE CENTRAL GREAT LAKES REGION. STEEP LOW LEVEL
LAPSE RATES...COUPLED WITH NORTHERLY FLOW OFF LAKE HURON SHOULD
ASSURE CLOUDY SKIES ACROSS SOUTHEAST MICHIGAN...WITH EVEN ENOUGH LOW
LEVEL SATURATION/CAPE TO POTENTIALLY CAUSE A FEW LIGHT
SHOWERS/SPRINKLES. PRONOUNCED SUBSIDENCE INVERSION IN PLACE TUESDAY
NIGHT EXPECTED TO TRAP LOW LEVEL MOISTURE TO MAINTAIN MOSTLY CLOUDY
SKIES THROUGH THE NIGHT. WITH SURFACE HIGH/RIDGE IN PLACE AND UPPER
LEVEL RIDGE OVERHEAD ON WEDNESDAY...MAY PROVE DIFFICULT TO MIX OUT
THE LOW LEVEL MOISTURE/CLOUDS...ESPECIALLY OVER THE THUMB REGION.

UPPER LEVEL LOW OVER THE GREAT BASIN EARLY THIS MORNING WILL BE
INFUSED BY UPPER LEVEL LOW/COLD POOL OFF THE BRITISH COLUMBIA
COAST...LEADING TO LONGWAVE TROUGH ENCOMPASSING WESTERN NORTH
AMERICA TUESDAY-WEDNESDAY. GOOD MOISTURE ADVECTION WILL TRANSLATE
NORTHEAST INTO THE GREAT LAKES REGION AS WE HEAD INTO
THURSDAY...WITH PW VALUES RISING ABOVE 1.5 INCHES. TIMING OF THE
850-700 MB THETA-E RIDGE AXIS AHEAD OF THE COLD FRONT LOOKS TO BE
THURSDAY EVENING...SUPPORTING HIGH LIKELY POPS AS AGRESSIVE HEIGHT
FALLS TAKE OVER TO END THE WORK WEEK. THERE IS EVEN A SLIGHT
CHANCE OF THUNDERSTORMS WITH THE COLD FRONT..AS SHOWALTER INDEX
PROGGED TO GO SLIGHTLY BELOW ZERO THURSDAY EVENING...PER 00Z EURO.

&&

.MARINE...

A COLD FRONT WILL SLIDE THROUGH THE CENTRAL GREAT LAKES TONIGHT.
SOLID NORTH WINDS OF 15 TO 25 KNOTS WILL FOLLOW BEHIND THE COLD
FRONT INTO TUESDAY MORNING. WITH THE COLD ADVECTION AND STRONGER
WINDS...WAVES WILL BUILD IN EXCESS OF 4 FEET OVER CENTRAL AND
SOUTHERN LAKE HURON...AND SMALL CRAFT ADVISORIES HAVE BEEN ISSUED.
WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH PRESSURE BUILDS
BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL PERSIST
WEDNESDAY AND THURSDAY.

&&

.AVIATION...ISSUED 1158 PM EDT SUN SEP 28 2014

//DISCUSSION...

A FRAGILE FOG SCENARIO REMAINS IN PLACE OVER SE MICHIGAN AS DIFFUSE
SURFACE HIGH PRESSURE LINGERS OVER THE REGION THROUGH THE MORNING.
SCATTERED ALTOCU AND CIRRUS IN THE DTW AREA AND SHALLOWER BOUNDARY
LAYER MOISTURE IS EXPECTED TO LIMIT RESTRICTION TO MVFR BUT IFR IS
EXPECTED FARTHER NORTH DUE TO LESS CLOUDS AND DEEPER MOISTURE...
ESPECIALLY IN PRONE AREAS LIKE PTK AND FNT. EVEN THERE...THE DEPTH
OF MOISTURE IS STILL SHALLOW ENOUGH FOR WIDE SWINGS IN VISIBILITY
AND INCONSISTENT COVERAGE. THIS ALSO MEANS A MID MORNING DISSIPATION
IS LIKELY FOLLOWED BY A RETURN TO VFR IN LIGHT WESTERLY WIND THROUGH
THE AFTERNOON. A SHARP COLD FRONT WILL THEN MOVE IN BY EARLY MONDAY
EVENING AT MBS AND SPREAD MVFR CEILING AND VISIBILITY IN FOG AND
SHOWERS OVER ALL TERMINAL SITES DURING THE REST OF MONDAY NIGHT.

//DTW THRESHOLD THREATS...

* NONE.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...SC
LONG TERM....SF
MARINE.......SF
AVIATION.....BT


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








000
FXUS63 KDTX 290715
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
315 AM EDT MON SEP 29 2014

.SHORT TERM...TODAY AND TONIGHT

A SURFACE COLD FRONT IS SHOWN STRETCHING FROM WRN NEBRASKA...ACROSS
THE UP OF MICHIGAN...AND INTO SRN QUEBEC AS OF 07Z. THERE IS A VERY
TIGHT LOW LEVEL BAROCLINIC ZONE ALONG THIS BOUNDARY AS EVIDENT BY
YESTERDAYS HIGHS IN THE 70S AND 80S SOUTH OF THE FRONT AND 40S AND
50S NORTH. RECENT SURFACE ANALYSES HAVE SHOWN THE DEVELOPMENT OF A
WEAK LOW ALONG THE BOUNDARY OVER CNTL UPPER MI. THIS SFC REFLECTION
HAS DEVELOPED WITHIN THE ENTRANCE REGION OF THE UPPER JET MAX AND
AHEAD OF A MID LEVEL TROUGH NOW ROTATING ACROSS NW ONTARIO AND SRN
MANITOBA.

THE WATER VAPOR LOOP HAS ALREADY BEEN SHOWING THIS MID LEVEL WAVE
AMPLIFYING AS IT TRACKS TOWARD THE E-SE. THIS IS IN SUPPORT OF THE
ENTIRE 00Z MODEL SUITE WHICH SHOW THIS WAVE UNDERGOING RAPID
DEEPENING AS IT TRACKS INTO NRN LOWER MI THIS EVENING...EVENTUALLY
EVOLVING INTO A COMPACT CLOSED MID LEVEL LOW OVER LAKE HURON BY 12Z
TUES. THE CORRESPONDING MID LEVEL HEIGHT FALLS WILL OVERSPREAD SE MI
TONIGHT ALONG WITH A NARROW AXIS OF STRONG DIFFERENTIAL CYCLONIC
VORTICITY ADVECTION. SE MI IS ALSO EXPECTED TO RESIDE IN THE
EXIT REGION OF A CYCLONICALLY CURVED UPPER JET MAX WITHIN THE BASE
OF THE UPPER TROUGH...ENHANCING LARGE SCALE UPPER DIVERGENCE. THE
00Z MODEL SUITE HAVE A REASONABLE HANDEL ON THE LOW-MID LEVEL
MOISTURE PLUME NOW STRETCHING ACROSS THE NRN GREAT LAKES...WHICH IS
FORECAST TO NARROW AS IT WORKS INTO SE MI TONIGHT. THE MOISTURE
LOOKS TO BE ENOUGH TO RESULT IN A BRIEF PERIOD /2 TO 4 HOURS/ OF
SHOWERS CONSIDERING THE STRONG LARGE SCALE ASCENT. THIS BRIEF WINDOW
WHEN THE FORCING AND MOISTURE WILL ALIGN IS EXPECTED TO OCCUR ALONG
AND JUST BEHIND THE SFC FRONT WHICH THE HI RES SOLUTIONS SUGGEST
WILL BE DRIVEN INTO THE TRI CITIES AROUND 00Z AND ACROSS METRO
DETROIT AROUND 06Z. MODEL CROSS SECTIONS SHOW SOME WEAK CONVECTIVE
INSTABILITY AS RAPID COOLING ALOFT STEEPENS MID LEVEL LAPSE RATES.
IN LIGHT OF THE BRIEF YET INTENSE PERIOD OF LARGE SCALE
ASCENT...SOME ISOLATED THUNDERSTORMS CAN NOT BE RULED OUT.

LIKE THE LAST SEVERAL MORNINGS...THERE WILL BE SOME FOG AROUND TO
START THE DAY. MODEL SOUNDINGS AND THE RECENT IR SUGGEST THIS
MOISTURE IS QUITE SHALLOW AND WILL MIX OUT FAIRLY QUICKLY THIS
MORNING. THE LACK OF MUCH CLOUD COVER AHEAD OF THE COLD FRONT AND
SUBTLE LOW LEVEL WARM AIR ADVECTION IN THE PREFRONTAL AIRMASS WILL
BOOST DAYTIME HIGHS TO THE UPPER 70S/AROUND 80. STRONG LOW LEVEL
COLD AIR ADVECTION TONIGHT WILL RAPIDLY DROP TEMPS INTO THE 40S
FOLLOWING FROPA. CHANCE POPS WILL BE CONTINUED THROUGH DAYBREAK TUES
AS EXTENSIVE POST FRONTAL STRATUS WITHIN THE DEEPENING INVERSION MAY
RESULT IN SOME DRIZZLE.

&&

.LONG TERM...

MUCH COOLER WEATHER ON TUESDAY...AS 500 MB LOW/COLD POOL (0 C AT 700
MB) SLOWLY EXITS THE CENTRAL GREAT LAKES REGION. STEEP LOW LEVEL
LAPSE RATES...COUPLED WITH NORTHERLY FLOW OFF LAKE HURON SHOULD
ASSURE CLOUDY SKIES ACROSS SOUTHEAST MICHIGAN...WITH EVEN ENOUGH LOW
LEVEL SATURATION/CAPE TO POTENTIALLY CAUSE A FEW LIGHT
SHOWERS/SPRINKLES. PRONOUNCED SUBSIDENCE INVERSION IN PLACE TUESDAY
NIGHT EXPECTED TO TRAP LOW LEVEL MOISTURE TO MAINTAIN MOSTLY CLOUDY
SKIES THROUGH THE NIGHT. WITH SURFACE HIGH/RIDGE IN PLACE AND UPPER
LEVEL RIDGE OVERHEAD ON WEDNESDAY...MAY PROVE DIFFICULT TO MIX OUT
THE LOW LEVEL MOISTURE/CLOUDS...ESPECIALLY OVER THE THUMB REGION.

UPPER LEVEL LOW OVER THE GREAT BASIN EARLY THIS MORNING WILL BE
INFUSED BY UPPER LEVEL LOW/COLD POOL OFF THE BRITISH COLUMBIA
COAST...LEADING TO LONGWAVE TROUGH ENCOMPASSING WESTERN NORTH
AMERICA TUESDAY-WEDNESDAY. GOOD MOISTURE ADVECTION WILL TRANSLATE
NORTHEAST INTO THE GREAT LAKES REGION AS WE HEAD INTO
THURSDAY...WITH PW VALUES RISING ABOVE 1.5 INCHES. TIMING OF THE
850-700 MB THETA-E RIDGE AXIS AHEAD OF THE COLD FRONT LOOKS TO BE
THURSDAY EVENING...SUPPORTING HIGH LIKELY POPS AS AGRESSIVE HEIGHT
FALLS TAKE OVER TO END THE WORK WEEK. THERE IS EVEN A SLIGHT
CHANCE OF THUNDERSTORMS WITH THE COLD FRONT..AS SHOWALTER INDEX
PROGGED TO GO SLIGHTLY BELOW ZERO THURSDAY EVENING...PER 00Z EURO.

&&

.MARINE...

A COLD FRONT WILL SLIDE THROUGH THE CENTRAL GREAT LAKES TONIGHT.
SOLID NORTH WINDS OF 15 TO 25 KNOTS WILL FOLLOW BEHIND THE COLD
FRONT INTO TUESDAY MORNING. WITH THE COLD ADVECTION AND STRONGER
WINDS...WAVES WILL BUILD IN EXCESS OF 4 FEET OVER CENTRAL AND
SOUTHERN LAKE HURON...AND SMALL CRAFT ADVISORIES HAVE BEEN ISSUED.
WINDS WILL QUICKLY DIMINISH BY TUESDAY NIGHT AS HIGH PRESSURE BUILDS
BACK INTO THE REGION. LIGHT WINDS AND LOW WAVES WILL PERSIST
WEDNESDAY AND THURSDAY.

&&

.AVIATION...ISSUED 1158 PM EDT SUN SEP 28 2014

//DISCUSSION...

A FRAGILE FOG SCENARIO REMAINS IN PLACE OVER SE MICHIGAN AS DIFFUSE
SURFACE HIGH PRESSURE LINGERS OVER THE REGION THROUGH THE MORNING.
SCATTERED ALTOCU AND CIRRUS IN THE DTW AREA AND SHALLOWER BOUNDARY
LAYER MOISTURE IS EXPECTED TO LIMIT RESTRICTION TO MVFR BUT IFR IS
EXPECTED FARTHER NORTH DUE TO LESS CLOUDS AND DEEPER MOISTURE...
ESPECIALLY IN PRONE AREAS LIKE PTK AND FNT. EVEN THERE...THE DEPTH
OF MOISTURE IS STILL SHALLOW ENOUGH FOR WIDE SWINGS IN VISIBILITY
AND INCONSISTENT COVERAGE. THIS ALSO MEANS A MID MORNING DISSIPATION
IS LIKELY FOLLOWED BY A RETURN TO VFR IN LIGHT WESTERLY WIND THROUGH
THE AFTERNOON. A SHARP COLD FRONT WILL THEN MOVE IN BY EARLY MONDAY
EVENING AT MBS AND SPREAD MVFR CEILING AND VISIBILITY IN FOG AND
SHOWERS OVER ALL TERMINAL SITES DURING THE REST OF MONDAY NIGHT.

//DTW THRESHOLD THREATS...

* NONE.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...OUTER SAGINAW BAY AND THE NEARSHORE WATERS
     FROM PORT AUSTIN TO PORT SANILAC...FROM 1 AM TUESDAY TO 6 PM
     TUESDAY.

LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...SC
LONG TERM....SF
MARINE.......SF
AVIATION.....BT


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







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