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000
FXUS63 KDTX 010407
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1207 AM EDT SAT NOV 1 2014

.AVIATION...

//DISCUSSION...

MVFR IN CEILING AND SNOW SHOWERS WILL CONTINUE THROUGH SUNRISE...
ESPECIALLY IN THE DTW CORRIDOR...WHILE FINALLY MOVING EAST OF FNT.
THANKS TO THE STRONG NORTHERLY FLOW DOWNSLOPE FROM NORTHERN
LOWER...MBS WILL HAVE LOW END VFR CEILING MOST OF THE TIME UNTIL
CEILING BEGINS TO BREAK UP ENTIRELY BY MID AFTERNOON AS HIGH
PRESSURE BUILDS OVER THE WESTERN GREAT LAKES. DAYTIME BOUNDARY LAYER
GROWTH WILL MAINTAIN MVFR CEILING AND GUSTY NORTH WIND ELSEWHERE
THROUGH AT LEAST MID AFTERNOON.

FOR DTW... NORTH WIND GUSTS NEAR 30 KNOTS WILL CONTINUE TO DRIVE
ENOUGH COLD AIR INTO THE METRO AREA FOR MOSTLY SNOW TO FALL DURING
THE REST OF THE NIGHT. NO ACCUMULATION IS EXPECTED AS SNOWFALL RATES
WILL REMAIN TOO LIGHT TO OVERWHELM WARM GROUND SURFACES.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FT THROUGH MID AFTERNOON.

* HIGH CONFIDENCE IN NORTHERLY WIND GUSTS 25-30 KNOTS.

* HIGH CONFIDENCE IN SNOW DURING THE NIGHT.

&&

.PREV DISCUSSION...ISSUED 1018 PM EDT FRI OCT 31 2014

UPDATE...

EARLY EVENING OBSERVATIONS OVER INLAND AREAS SHOW WIND GUSTS
SETTLING BELOW 40 MPH AND ALLOWED FOR THE CANCELLATION OF THE
WIND ADVISORY IN OUR EARLIER UPDATE. THE PLAN FOR THE NEXT UPDATE
IS TO DROP THE WIND ADVISORY FOR THE INNER BAY COUNTIES BUT EXTEND
THROUGH 4 AM FOR THE LAKE HURON COUNTIES. THE LAKESHORE FLOOD
ADVISORY RUNS THROUGH NOON SATURDAY BUT WATER LEVELS AT ESSEXVILLE
INDICATE A STEADY DOWNWARD TREND THAT WILL LIKELY ALLOW
CANCELLATION BY THE NEXT FORECAST PACKAGE AT 4 AM.

WHILE DROPPING BELOW HEADLINE CRITERIA...THE WIND WILL REMAIN
GUSTY OVER LAND AREAS AND AT GALE FORCE OVER LAKE HURON. THE
PERSISTENT NORTHEAST FLOW OF COLD AIR OVER THE WARM LAKE WATER
WILL KEEP A LAKE EFFECT SNOW...OR RAIN SNOW MIX...IN THE FORECAST
THROUGH SATURDAY MORNING. EARLY IN THE NIGHT...THE WIND FIELD WILL
SUPPORT A CONCENTRATED AREA OF LOW LEVEL CONVERGENCE ROUGHLY ALONG
AND EAST OF A LINE FROM OSCODA TO FLINT WHILE CONVECTIVE DEPTH
ALLOWS BANDS OF LAKE EFFECT TO EASILY REACH THE M-59 CORRIDOR.
MODEL WIND FIELDS CAPTURE THE CONVERGENCE ZONE BETWEEN THE LAKE
AND LOWER MICHIGAN QUITE WELL AND SUPPORT MAINTENANCE OF HIGHER
POPS FROM ABOUT BAY CITY TO FLINT LONGER IN THE NIGHT TO GO ALONG
WITH CATEGORICAL POPS FOR THE REST OF THE THUMB. THE FLOW THEN
BECOMES NORTHERLY ENOUGH TO PUSH ACTIVITY TOWARD THE THUMB
SHORELINE SATURDAY MORNING WHILE CONVECTIVE DEPTH IS SQUASHED BY
MID LEVEL SUBSIDENCE TRAILING THE SYSTEM. EVENING OBSERVATIONS
OVER NORTHERN LAKE HURON AND NORTHERN LOWER INDICATE THIS IS
PROVING EFFECTIVE AT DIMINISHING LAKE EFFECT SUBSTANTIALLY. THIS
MAKES THE MODEST GRASSY ACCUMULATION OF AN INCH OR LESS IN THE
GOING FORECAST APPEAR ON TARGET THROUGH NOON SATURDAY.

PREV DISCUSSION...ISSUED 356 PM EDT FRI OCT 31 2014

SHORT TERM... THROUGH TONIGHT

POST-FRONTAL COLD AIR ADVECTION RAMPING UP WITHIN A DEEPENING
NORTHERLY FLOW AT PRESS TIME AS SE MICHIGAN SETTLES FIRMLY WITHIN
THE EASTERN PERIPHERY OF THE INBOUND HEIGHT FALLS ATTENDANT TO AN
AMPLIFYING MID LEVEL TROUGH AXIS.  MID LEVEL FORCING WITHIN THE EAST-
SOUTHEAST PIVOTING DEFORMATION AXIS AND SUBSEQUENT MAINTENANCE OF
THE EXISTING MID LEVEL FRONTAL FORCING WILL BE SLOW TO RELEASE
EASTWARD OVER THE NEXT FEW HOURS /PRIOR TO 00-02Z/...OUTSIDE OF THE
TRI-CITIES WHERE RADAR TRENDS WOULD SUGGEST THE LOSS OF BOTH THE
SYNOPTIC FORCING AND ENSUING TRAILING DRY AIR ADVECTION WILL BEGIN
TO DIMINISH CHANCES.  ELSEWHERE THE ANTECEDANT ENVIRONMENT WILL
CONTINUE TO SUPPORT SHOWER PRODUCTION THROUGH THE EVENING HOURS.
THE ADVECTIVE PROCESS WILL CONTINUE TO WORK INTO THE RESIDUAL
`WARMER` BOUNDARY LAYER...EVENTUALLY TILTING THE BULK OF THE THERMAL
PROFILE BELOW FREEZING.  THE TIMING OF THIS PROCESS CONTINUES TO
POINT TOWARD A WINDOW FOR RAIN TO MIX WITH AND/OR CHANGEOVER TO SNOW
AT LEAST AS FAR SOUTH AS THE M-59 CORRIDOR BEFORE THE DEEPER
MOISTURE STRIPS EAST.  PLACES THAT MANAGE A LONGER RESIDENCE TIME
WILL SEE SOME MINOR ACCUMULATION...CONFINED TO JUST GRASSY SURFACES
GIVEN THE WET AND RELATIVELY WARMER ROAD SURFACE CONDITIONS.

A STEADILY INCREASING WIND FIELD WILL ALSO CONTRIBUTE TO A LESS THAN
DESIRABLE CONDITION FOR THOSE WITH OUTDOOR EVENING PLANS.  RECENT
OBSERVATIONS INDICATE GUSTS AS HIGH AS 50 MPH ARE ONGOING ACROSS
PORTIONS OF THE THUMB AND INTO BAY COUNTY AS THE STRENGTHENING
GRADIENT FLOW CAPITALIZES ON THE EMERGING INSTABILITY OVER THE LAKE
HURON WATERS AND DOWN SAGINAW BAY.  PEAK GUST POTENTIAL CERTAINLY
STILL CARRIES A BIT MORE UNCERTAINTY FURTHER INLAND...MORE RELIANCE
ON SEEING SOME COMBINATION OF MIXING AND ISENTROPIC DESCENT TO
AUGMENT A FIRM WIND FIELD EMBEDDED WITHIN THE 950-850 MB LAYER.
GREATEST WINDOW FOR STRONGER GUSTS WILL EXIST 21Z-03Z...AND WILL
HOLD FIRM WITH THE WIND ADVISORY FOR LOCALES ALONG/NORTH OF THE M-59
CORRIDOR.

BOTH THE RESIDUAL TROUGHING AND DEEPER MOISTURE WILL BE SLOWER TO
EXIT ACROSS THE EASTERN THUMB...THE DEPTH SUSTAINED BY A RESPECTABLE
LOOKING LAKE RESPONSE UNDER A LONGER FETCH / 020-030 WIND
TRAJECTORY.  THIS WILL YIELD AN INCREASING COVERAGE OF LIGHT LAKE
EFFECT SNOW ACROSS THE SOUTHERN LAKE HURON BASIN...LIKELY PROVIDING
SOME RENEWED SNOW SHOWER ACTIVITY FOR THE THUMB CORRIDOR SATURDAY
MORNING.  AGAIN SOME LIGHT ACCUMULATION /HALF INCH TYPE AMOUNTS/
WILL BE PLAUSIBLE ON GRASSY SURFACES PRIOR TO 12Z.

LONG TERM...SATURDAY THROUGH THURSDAY

NOTICEABLY DIFFERENT AIRMASS THIS WEEKEND AS HIGH PRESSURE FROM
CANADA BUILDS INTO THE REGION BEHIND THE EXITING LOW PRESSURE SYSTEM.
THE AXIS OF THE MID/UPPER LEVEL TROUGH WILL BE EAST OF THE AREA BY
12Z SATURDAY BUT THE COLD POOL WILL BE SLOWER TO EXIT RESULTING IN
UNSEASONABLY COOL TEMPERATURES. VERY AMPLIFIED LONG WAVE PATTERN
WILL SET UP OVER THE CONUS BY SUNDAY WITH TROUGHS OVER BOTH COASTS
AND RIDGING BUILDING INTO THE GREAT LAKES. THIS WILL ALLOW IMPROVING
CONDITIONS BACK TO SEASONAL NORMS BY THE BEGINNING OF THE NEW WEEK.

SATURDAY WILL BE COLD WITH LAKE EFFECT SNOW SHOWERS OVER PORTIONS OF
THE THUMB WITH GOOD NE FLOW OVER LAKE HURON ON THE BACKSIDE OF THE
EXITING LOW. TEMPS AT 500MB WILL BE AROUND -28C TO START THE DAY
WITH 850MB TEMPS AROUND -9C. NE WINDS WILL STILL BE ELEVATED TO
START THE DAY DUE TO A TIGHT PRESSURE GRADIENT BETWEEN THE INCOMING
HIGH AND EXITING LOW. WINDS WILL LET UP BY SATURDAY NIGHT BUT ONLY
AFTER GUSTING TO AROUND 25 MPH IN THE AFTERNOON AGAIN. ATTENTION IS
STILL AIMED AT POTENTIAL FOR LAKE EFFECT SNOW FOR THE EASTERN THUMB
PERSISTING INTO THE DAY SATURDAY FROM OVERNIGHT ACTIVITY. THE FLOW
LOOKS TO REMAIN OUT OF THE NORTH/NORTHEAST INTO THE AFTERNOON AND
WITH RELATIVELY WARMER WATERS THE HIRES SUITE IS IN PRETTY GOOD
AGREEMENT IN DEVELOPING A FEW LAKE EFFECT BANDS OVER THE THUMB. THE
INCOMING RIDGE WILL BE VERY DRY ALOFT THUS SCOURING OUT ANY BENEFIT
TO DEEP LAYER MOISTURE PROFILES...BUT BELOW THE INVERSION SATURATION
WILL REMAIN WITH FAVORABLE LL LAPSE RATES UP TO AROUND 850MB. TWO
POTENTIAL ISSUES WILL BE THE WARM GROUND AND TEMPERATURES INCREASING
TOWARD 40F. WITHOUT SOME GOOD SNOWFALL RATES IN THE BAND...IT MAY BE
HARD TO ACCUMULATE SNOW OUTSIDE OF ELEVATED SURFACES AND GRASSY
AREAS. DID INCREASE ACCUMS TO AROUND AN INCH FOR THE MORNING AND
EARLY AFTERNOON...AND WHEN ADDING THAT TO OVERNIGHT LAKE EFFECT
AMOUNTS COULD REACH AN INCH AND A HALF OR SO.

IMPROVED CONDITIONS FOR SUNDAY AS WAA IS UNDERWAY RAISING 500MB
TEMPS TO -16C AND 850MB TEMPS TO 4C AS FLOW BECOMES W/NW THROUGH THE
DAY. WITH HIGH PRESSURE OVERHEAD AND A DRY COLUMN...EXPECT A GOOD
DEAL OF SUN DURING THE DAY. HIGH TEMPS WILL RISE 5 TO 10 DEGREES
FROM SATURDAY...REACHING INTO THE MID 40S.

AN UPPER LEVEL RIDGE WILL BE IN PLACE OVER THE REGION ON MONDAY
BEFORE THE NEXT SYSTEM PUSHES THROUGH ON TUESDAY.  FRONTAL PASSAGE
WITH THIS SYSTEM WILL BRING INCREASED CHANCES FOR PRECIP OVER THE
AREA.  THE REMAINDER OF THE WEEK WILL FEATURE A CONTINUED ACTIVE
PATTERN OVER THE GREAT LAKES AS AREAS OF VORTICITY ROTATE AROUND THE
BASE OF THE UPPER LEVEL TROUGH.

MARINE...GALE FORCE WINDS HAVE SPREAD ACROSS ALL OF LAKE HURON
TODAY AND ARE WORKING THEIR WAY TOWARD LAKES ST CLAIR AND ERIE THIS
EVENING AS AN ARCTIC AIRMASS PUSHES SOUTHWARD THROUGH THE REGION.
NORTHEAST FLOW IS BEING ENHANCED BY A TIGHTENING PRESSURE GRADIENT
AS HIGH PRESSURE RUNS UP AGAINST THE SLOWLY DEPARTING LOW. THIS
COMBINED WITH UNSTABLE COLD AIR ALOFT IS LEADING TO THE WIDESPREAD
GALES. THESE CONDITIONS WILL PERSIST THROUGH TONIGHT BEFORE TAPERING
OFF THROUGH THE DAY SATURDAY AS HIGH PRESSURE BUILDS OVER THE
REGION.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...LAKESHORE FLOOD ADVISORY UNTIL NOON EDT TODAY FOR MIZ048-049-054-
     055-063.

     WIND ADVISORY UNTIL 4 AM EDT EARLY THIS MORNING FOR MIZ049-055-063.

LAKE HURON...GALE WARNING UNTIL NOON EDT TODAY FOR LHZ363-441>443-462>464.

     GALE WARNING UNTIL 8 AM EDT THIS MORNING FOR LHZ421-422.

LAKE ST CLAIR...GALE WARNING UNTIL 8 AM EDT THIS MORNING FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING UNTIL 8 AM EDT THIS MORNING FOR LEZ444.

&&

$$

AVIATION.....BT
UPDATE.......BT
SHORT TERM...MR
LONG TERM....DRK/SS
MARINE.......DRK


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





000
FXUS63 KDTX 010218
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1018 PM EDT FRI OCT 31 2014

.UPDATE...

EARLY EVENING OBSERVATIONS OVER INLAND AREAS SHOW WIND GUSTS
SETTLING BELOW 40 MPH AND ALLOWED FOR THE CANCELLATION OF THE
WIND ADVISORY IN OUR EARLIER UPDATE. THE PLAN FOR THE NEXT UPDATE
IS TO DROP THE WIND ADVISORY FOR THE INNER BAY COUNTIES BUT EXTEND
THROUGH 4 AM FOR THE LAKE HURON COUNTIES. THE LAKESHORE FLOOD
ADVISORY RUNS THROUGH NOON SATURDAY BUT WATER LEVELS AT ESSEXVILLE
INDICATE A STEADY DOWNWARD TREND THAT WILL LIKELY ALLOW
CANCELLATION BY THE NEXT FORECAST PACKAGE AT 4 AM.

WHILE DROPPING BELOW HEADLINE CRITERIA...THE WIND WILL REMAIN
GUSTY OVER LAND AREAS AND AT GALE FORCE OVER LAKE HURON. THE
PERSISTENT NORTHEAST FLOW OF COLD AIR OVER THE WARM LAKE WATER
WILL KEEP A LAKE EFFECT SNOW...OR RAIN SNOW MIX...IN THE FORECAST
THROUGH SATURDAY MORNING. EARLY IN THE NIGHT...THE WIND FIELD WILL
SUPPORT A CONCENTRATED AREA OF LOW LEVEL CONVERGENCE ROUGHLY ALONG
AND EAST OF A LINE FROM OSCODA TO FLINT WHILE CONVECTIVE DEPTH
ALLOWS BANDS OF LAKE EFFECT TO EASILY REACH THE M-59 CORRIDOR.
MODEL WIND FIELDS CAPTURE THE CONVERGENCE ZONE BETWEEN THE LAKE
AND LOWER MICHIGAN QUITE WELL AND SUPPORT MAINTENANCE OF HIGHER
POPS FROM ABOUT BAY CITY TO FLINT LONGER IN THE NIGHT TO GO ALONG
WITH CATEGORICAL POPS FOR THE REST OF THE THUMB. THE FLOW THEN
BECOMES NORTHERLY ENOUGH TO PUSH ACTIVITY TOWARD THE THUMB
SHORELINE SATURDAY MORNING WHILE CONVECTIVE DEPTH IS SQUASHED BY
MID LEVEL SUBSIDENCE TRAILING THE SYSTEM. EVENING OBSERVATIONS
OVER NORTHERN LAKE HURON AND NORTHERN LOWER INDICATE THIS IS
PROVING EFFECTIVE AT DIMINISHING LAKE EFFECT SUBSTANTIALLY. THIS
MAKES THE MODEST GRASSY ACCUMULATION OF AN INCH OR LESS IN THE
GOING FORECAST APPEAR ON TARGET THROUGH NOON SATURDAY.

&&

.AVIATION...ISSUED 748 PM EDT FRI OCT 31 2014

//DISCUSSION...

IFR/MVFR IN MIXED RAIN AND SNOW WILL CONTINUE THROUGH THE EVENING IN
COLD AIR DRIVEN OVER THE REGION BY NORTH WIND GUSTING TO 30 KNOTS.
THE WESTERN EDGE OF THE PRECIPITATION HAS ALREADY PASSED MBS AND
WILL MAKE SLOW EASTWARD PROGRESS DURING THE NIGHT. THANKS TO THE
STRONG NORTHERLY FLOW DOWNSLOPE FROM NORTHERN LOWER...MBS WILL HAVE
LOW END VFR CEILING MOST OF THE TIME UNTIL THE EARLY MORNING HOURS.
DAYTIME BOUNDARY LAYER GROWTH WILL MAINTAIN MVFR CEILING AND GUSTY
NORTH WIND ELSEWHERE THROUGH SATURDAY.

FOR DTW... NORTH WIND GUSTS AROUND 30 KNOTS WILL CONTINUE TO DRIVE
ENOUGH COLD AIR INTO THE METRO AREA FOR A RAIN/SNOW MIX DURING THE
REST OF THE EVENING INTO THE OVERNIGHT HOURS. THE MIXED NATURE OF
THE PRECIPITATION AND WARM GROUND WILL PREVENT ANY ACCUMULATION.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FT THROUGH SATURDAY.

* HIGH CONFIDENCE IN NORTHERLY WIND GUSTS 25-30 KNOTS.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN TONIGHT.

&&

.PREV DISCUSSION...ISSUED 356 PM EDT FRI OCT 31 2014

SHORT TERM... THROUGH TONIGHT

POST-FRONTAL COLD AIR ADVECTION RAMPING UP WITHIN A DEEPENING
NORTHERLY FLOW AT PRESS TIME AS SE MICHIGAN SETTLES FIRMLY WITHIN
THE EASTERN PERIPHERY OF THE INBOUND HEIGHT FALLS ATTENDANT TO AN
AMPLIFYING MID LEVEL TROUGH AXIS.  MID LEVEL FORCING WITHIN THE EAST-
SOUTHEAST PIVOTING DEFORMATION AXIS AND SUBSEQUENT MAINTENANCE OF
THE EXISTING MID LEVEL FRONTAL FORCING WILL BE SLOW TO RELEASE
EASTWARD OVER THE NEXT FEW HOURS /PRIOR TO 00-02Z/...OUTSIDE OF THE
TRI-CITIES WHERE RADAR TRENDS WOULD SUGGEST THE LOSS OF BOTH THE
SYNOPTIC FORCING AND ENSUING TRAILING DRY AIR ADVECTION WILL BEGIN
TO DIMINISH CHANCES.  ELSEWHERE THE ANTECEDANT ENVIRONMENT WILL
CONTINUE TO SUPPORT SHOWER PRODUCTION THROUGH THE EVENING HOURS.
THE ADVECTIVE PROCESS WILL CONTINUE TO WORK INTO THE RESIDUAL
`WARMER` BOUNDARY LAYER...EVENTUALLY TILTING THE BULK OF THE THERMAL
PROFILE BELOW FREEZING.  THE TIMING OF THIS PROCESS CONTINUES TO
POINT TOWARD A WINDOW FOR RAIN TO MIX WITH AND/OR CHANGEOVER TO SNOW
AT LEAST AS FAR SOUTH AS THE M-59 CORRIDOR BEFORE THE DEEPER
MOISTURE STRIPS EAST.  PLACES THAT MANAGE A LONGER RESIDENCE TIME
WILL SEE SOME MINOR ACCUMULATION...CONFINED TO JUST GRASSY SURFACES
GIVEN THE WET AND RELATIVELY WARMER ROAD SURFACE CONDITIONS.

A STEADILY INCREASING WIND FIELD WILL ALSO CONTRIBUTE TO A LESS THAN
DESIRABLE CONDITION FOR THOSE WITH OUTDOOR EVENING PLANS.  RECENT
OBSERVATIONS INDICATE GUSTS AS HIGH AS 50 MPH ARE ONGOING ACROSS
PORTIONS OF THE THUMB AND INTO BAY COUNTY AS THE STRENGTHENING
GRADIENT FLOW CAPITALIZES ON THE EMERGING INSTABILITY OVER THE LAKE
HURON WATERS AND DOWN SAGINAW BAY.  PEAK GUST POTENTIAL CERTAINLY
STILL CARRIES A BIT MORE UNCERTAINTY FURTHER INLAND...MORE RELIANCE
ON SEEING SOME COMBINATION OF MIXING AND ISENTROPIC DESCENT TO
AUGMENT A FIRM WIND FIELD EMBEDDED WITHIN THE 950-850 MB LAYER.
GREATEST WINDOW FOR STRONGER GUSTS WILL EXIST 21Z-03Z...AND WILL
HOLD FIRM WITH THE WIND ADVISORY FOR LOCALES ALONG/NORTH OF THE M-59
CORRIDOR.

BOTH THE RESIDUAL TROUGHING AND DEEPER MOISTURE WILL BE SLOWER TO
EXIT ACROSS THE EASTERN THUMB...THE DEPTH SUSTAINED BY A RESPECTABLE
LOOKING LAKE RESPONSE UNDER A LONGER FETCH / 020-030 WIND
TRAJECTORY.  THIS WILL YIELD AN INCREASING COVERAGE OF LIGHT LAKE
EFFECT SNOW ACROSS THE SOUTHERN LAKE HURON BASIN...LIKELY PROVIDING
SOME RENEWED SNOW SHOWER ACTIVITY FOR THE THUMB CORRIDOR SATURDAY
MORNING.  AGAIN SOME LIGHT ACCUMULATION /HALF INCH TYPE AMOUNTS/
WILL BE PLAUSIBLE ON GRASSY SURFACES PRIOR TO 12Z.

LONG TERM...SATURDAY THROUGH THURSDAY

NOTICEABLY DIFFERENT AIRMASS THIS WEEKEND AS HIGH PRESSURE FROM
CANADA BUILDS INTO THE REGION BEHIND THE EXITING LOW PRESSURE SYSTEM.
THE AXIS OF THE MID/UPPER LEVEL TROUGH WILL BE EAST OF THE AREA BY
12Z SATURDAY BUT THE COLD POOL WILL BE SLOWER TO EXIT RESULTING IN
UNSEASONABLY COOL TEMPERATURES. VERY AMPLIFIED LONG WAVE PATTERN
WILL SET UP OVER THE CONUS BY SUNDAY WITH TROUGHS OVER BOTH COASTS
AND RIDGING BUILDING INTO THE GREAT LAKES. THIS WILL ALLOW IMPROVING
CONDITIONS BACK TO SEASONAL NORMS BY THE BEGINNING OF THE NEW WEEK.

SATURDAY WILL BE COLD WITH LAKE EFFECT SNOW SHOWERS OVER PORTIONS OF
THE THUMB WITH GOOD NE FLOW OVER LAKE HURON ON THE BACKSIDE OF THE
EXITING LOW. TEMPS AT 500MB WILL BE AROUND -28C TO START THE DAY
WITH 850MB TEMPS AROUND -9C. NE WINDS WILL STILL BE ELEVATED TO
START THE DAY DUE TO A TIGHT PRESSURE GRADIENT BETWEEN THE INCOMING
HIGH AND EXITING LOW. WINDS WILL LET UP BY SATURDAY NIGHT BUT ONLY
AFTER GUSTING TO AROUND 25 MPH IN THE AFTERNOON AGAIN. ATTENTION IS
STILL AIMED AT POTENTIAL FOR LAKE EFFECT SNOW FOR THE EASTERN THUMB
PERSISTING INTO THE DAY SATURDAY FROM OVERNIGHT ACTIVITY. THE FLOW
LOOKS TO REMAIN OUT OF THE NORTH/NORTHEAST INTO THE AFTERNOON AND
WITH RELATIVELY WARMER WATERS THE HIRES SUITE IS IN PRETTY GOOD
AGREEMENT IN DEVELOPING A FEW LAKE EFFECT BANDS OVER THE THUMB. THE
INCOMING RIDGE WILL BE VERY DRY ALOFT THUS SCOURING OUT ANY BENEFIT
TO DEEP LAYER MOISTURE PROFILES...BUT BELOW THE INVERSION SATURATION
WILL REMAIN WITH FAVORABLE LL LAPSE RATES UP TO AROUND 850MB. TWO
POTENTIAL ISSUES WILL BE THE WARM GROUND AND TEMPERATURES INCREASING
TOWARD 40F. WITHOUT SOME GOOD SNOWFALL RATES IN THE BAND...IT MAY BE
HARD TO ACCUMULATE SNOW OUTSIDE OF ELEVATED SURFACES AND GRASSY
AREAS. DID INCREASE ACCUMS TO AROUND AN INCH FOR THE MORNING AND
EARLY AFTERNOON...AND WHEN ADDING THAT TO OVERNIGHT LAKE EFFECT
AMOUNTS COULD REACH AN INCH AND A HALF OR SO.

IMPROVED CONDITIONS FOR SUNDAY AS WAA IS UNDERWAY RAISING 500MB
TEMPS TO -16C AND 850MB TEMPS TO 4C AS FLOW BECOMES W/NW THROUGH THE
DAY. WITH HIGH PRESSURE OVERHEAD AND A DRY COLUMN...EXPECT A GOOD
DEAL OF SUN DURING THE DAY. HIGH TEMPS WILL RISE 5 TO 10 DEGREES
FROM SATURDAY...REACHING INTO THE MID 40S.

AN UPPER LEVEL RIDGE WILL BE IN PLACE OVER THE REGION ON MONDAY
BEFORE THE NEXT SYSTEM PUSHES THROUGH ON TUESDAY.  FRONTAL PASSAGE
WITH THIS SYSTEM WILL BRING INCREASED CHANCES FOR PRECIP OVER THE
AREA.  THE REMAINDER OF THE WEEK WILL FEATURE A CONTINUED ACTIVE
PATTERN OVER THE GREAT LAKES AS AREAS OF VORTICITY ROTATE AROUND THE
BASE OF THE UPPER LEVEL TROUGH.

MARINE...GALE FORCE WINDS HAVE SPREAD ACROSS ALL OF LAKE HURON
TODAY AND ARE WORKING THEIR WAY TOWARD LAKES ST CLAIR AND ERIE THIS
EVENING AS AN ARCTIC AIRMASS PUSHES SOUTHWARD THROUGH THE REGION.
NORTHEAST FLOW IS BEING ENHANCED BY A TIGHTENING PRESSURE GRADIENT
AS HIGH PRESSURE RUNS UP AGAINST THE SLOWLY DEPARTING LOW. THIS
COMBINED WITH UNSTABLE COLD AIR ALOFT IS LEADING TO THE WIDESPREAD
GALES. THESE CONDITIONS WILL PERSIST THROUGH TONIGHT BEFORE TAPERING
OFF THROUGH THE DAY SATURDAY AS HIGH PRESSURE BUILDS OVER THE
REGION.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR MIZ048-049-054-055-063.
     (TO BE EXTENDED THROUGH 4 AM FOR THUMB COUNTIES)

     LAKESHORE FLOOD ADVISORY UNTIL NOON EDT SATURDAY FOR MIZ048-049-054-
     055-063.

LAKE HURON...GALE WARNING UNTIL NOON EDT SATURDAY FOR LHZ363-421-422-441>443-
             462>464.

LAKE ST CLAIR...GALE WARNING UNTIL 8 AM EDT SATURDAY FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING UNTIL 8 AM EDT SATURDAY
                               FOR LEZ444.

&&

$$

UPDATE.......BT
AVIATION.....BT
SHORT TERM...MR
LONG TERM....DRK/SS
MARINE.......DRK


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





000
FXUS63 KDTX 312348
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
748 PM EDT FRI OCT 31 2014

.AVIATION...

//DISCUSSION...

IFR/MVFR IN MIXED RAIN AND SNOW WILL CONTINUE THROUGH THE EVENING IN
COLD AIR DRIVEN OVER THE REGION BY NORTH WIND GUSTING TO 30 KNOTS.
THE WESTERN EDGE OF THE PRECIPITATION HAS ALREADY PASSED MBS AND
WILL MAKE SLOW EASTWARD PROGRESS DURING THE NIGHT. THANKS TO THE
STRONG NORTHERLY FLOW DOWNSLOPE FROM NORTHERN LOWER...MBS WILL HAVE
LOW END VFR CEILING MOST OF THE TIME UNTIL THE EARLY MORNING HOURS.
DAYTIME BOUNDARY LAYER GROWTH WILL MAINTAIN MVFR CEILING AND GUSTY
NORTH WIND ELSEWHERE THROUGH SATURDAY.

FOR DTW... NORTH WIND GUSTS AROUND 30 KNOTS WILL CONTINUE TO DRIVE
ENOUGH COLD AIR INTO THE METRO AREA FOR A RAIN/SNOW MIX DURING THE
REST OF THE EVENING INTO THE OVERNIGHT HOURS. THE MIXED NATURE OF
THE PRECIPITATION AND WARM GROUND WILL PREVENT ANY ACCUMULATION.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILING BELOW 5000 FT THROUGH SATURDAY.

* HIGH CONFIDENCE IN NORTHERLY WIND GUSTS 25-30 KNOTS.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN TONIGHT.

&&

.PREV DISCUSSION...ISSUED 356 PM EDT FRI OCT 31 2014

SHORT TERM... THROUGH TONIGHT

POST-FRONTAL COLD AIR ADVECTION RAMPING UP WITHIN A DEEPENING
NORTHERLY FLOW AT PRESS TIME AS SE MICHIGAN SETTLES FIRMLY WITHIN
THE EASTERN PERIPHERY OF THE INBOUND HEIGHT FALLS ATTENDANT TO AN
AMPLIFYING MID LEVEL TROUGH AXIS.  MID LEVEL FORCING WITHIN THE EAST-
SOUTHEAST PIVOTING DEFORMATION AXIS AND SUBSEQUENT MAINTENANCE OF
THE EXISTING MID LEVEL FRONTAL FORCING WILL BE SLOW TO RELEASE
EASTWARD OVER THE NEXT FEW HOURS /PRIOR TO 00-02Z/...OUTSIDE OF THE
TRI-CITIES WHERE RADAR TRENDS WOULD SUGGEST THE LOSS OF BOTH THE
SYNOPTIC FORCING AND ENSUING TRAILING DRY AIR ADVECTION WILL BEGIN
TO DIMINISH CHANCES.  ELSEWHERE THE ANTECEDANT ENVIRONMENT WILL
CONTINUE TO SUPPORT SHOWER PRODUCTION THROUGH THE EVENING HOURS.
THE ADVECTIVE PROCESS WILL CONTINUE TO WORK INTO THE RESIDUAL
`WARMER` BOUNDARY LAYER...EVENTUALLY TILTING THE BULK OF THE THERMAL
PROFILE BELOW FREEZING.  THE TIMING OF THIS PROCESS CONTINUES TO
POINT TOWARD A WINDOW FOR RAIN TO MIX WITH AND/OR CHANGEOVER TO SNOW
AT LEAST AS FAR SOUTH AS THE M-59 CORRIDOR BEFORE THE DEEPER
MOISTURE STRIPS EAST.  PLACES THAT MANAGE A LONGER RESIDENCE TIME
WILL SEE SOME MINOR ACCUMULATION...CONFINED TO JUST GRASSY SURFACES
GIVEN THE WET AND RELATIVELY WARMER ROAD SURFACE CONDITIONS.

A STEADILY INCREASING WIND FIELD WILL ALSO CONTRIBUTE TO A LESS THAN
DESIRABLE CONDITION FOR THOSE WITH OUTDOOR EVENING PLANS.  RECENT
OBSERVATIONS INDICATE GUSTS AS HIGH AS 50 MPH ARE ONGOING ACROSS
PORTIONS OF THE THUMB AND INTO BAY COUNTY AS THE STRENGTHENING
GRADIENT FLOW CAPITALIZES ON THE EMERGING INSTABILITY OVER THE LAKE
HURON WATERS AND DOWN SAGINAW BAY.  PEAK GUST POTENTIAL CERTAINLY
STILL CARRIES A BIT MORE UNCERTAINTY FURTHER INLAND...MORE RELIANCE
ON SEEING SOME COMBINATION OF MIXING AND ISENTROPIC DESCENT TO
AUGMENT A FIRM WIND FIELD EMBEDDED WITHIN THE 950-850 MB LAYER.
GREATEST WINDOW FOR STRONGER GUSTS WILL EXIST 21Z-03Z...AND WILL
HOLD FIRM WITH THE WIND ADVISORY FOR LOCALES ALONG/NORTH OF THE M-59
CORRIDOR.

BOTH THE RESIDUAL TROUGHING AND DEEPER MOISTURE WILL BE SLOWER TO
EXIT ACROSS THE EASTERN THUMB...THE DEPTH SUSTAINED BY A RESPECTABLE
LOOKING LAKE RESPONSE UNDER A LONGER FETCH / 020-030 WIND
TRAJECTORY.  THIS WILL YIELD AN INCREASING COVERAGE OF LIGHT LAKE
EFFECT SNOW ACROSS THE SOUTHERN LAKE HURON BASIN...LIKELY PROVIDING
SOME RENEWED SNOW SHOWER ACTIVITY FOR THE THUMB CORRIDOR SATURDAY
MORNING.  AGAIN SOME LIGHT ACCUMULATION /HALF INCH TYPE AMOUNTS/
WILL BE PLAUSIBLE ON GRASSY SURFACES PRIOR TO 12Z.

LONG TERM...SATURDAY THROUGH THURSDAY

NOTICEABLY DIFFERENT AIRMASS THIS WEEKEND AS HIGH PRESSURE FROM
CANADA BUILDS INTO THE REGION BEHIND THE EXITING LOW PRESSURE SYSTEM.
THE AXIS OF THE MID/UPPER LEVEL TROUGH WILL BE EAST OF THE AREA BY
12Z SATURDAY BUT THE COLD POOL WILL BE SLOWER TO EXIT RESULTING IN
UNSEASONABLY COOL TEMPERATURES. VERY AMPLIFIED LONG WAVE PATTERN
WILL SET UP OVER THE CONUS BY SUNDAY WITH TROUGHS OVER BOTH COASTS
AND RIDGING BUILDING INTO THE GREAT LAKES. THIS WILL ALLOW IMPROVING
CONDITIONS BACK TO SEASONAL NORMS BY THE BEGINNING OF THE NEW WEEK.

SATURDAY WILL BE COLD WITH LAKE EFFECT SNOW SHOWERS OVER PORTIONS OF
THE THUMB WITH GOOD NE FLOW OVER LAKE HURON ON THE BACKSIDE OF THE
EXITING LOW. TEMPS AT 500MB WILL BE AROUND -28C TO START THE DAY
WITH 850MB TEMPS AROUND -9C. NE WINDS WILL STILL BE ELEVATED TO
START THE DAY DUE TO A TIGHT PRESSURE GRADIENT BETWEEN THE INCOMING
HIGH AND EXITING LOW. WINDS WILL LET UP BY SATURDAY NIGHT BUT ONLY
AFTER GUSTING TO AROUND 25 MPH IN THE AFTERNOON AGAIN. ATTENTION IS
STILL AIMED AT POTENTIAL FOR LAKE EFFECT SNOW FOR THE EASTERN THUMB
PERSISTING INTO THE DAY SATURDAY FROM OVERNIGHT ACTIVITY. THE FLOW
LOOKS TO REMAIN OUT OF THE NORTH/NORTHEAST INTO THE AFTERNOON AND
WITH RELATIVELY WARMER WATERS THE HIRES SUITE IS IN PRETTY GOOD
AGREEMENT IN DEVELOPING A FEW LAKE EFFECT BANDS OVER THE THUMB. THE
INCOMING RIDGE WILL BE VERY DRY ALOFT THUS SCOURING OUT ANY BENEFIT
TO DEEP LAYER MOISTURE PROFILES...BUT BELOW THE INVERSION SATURATION
WILL REMAIN WITH FAVORABLE LL LAPSE RATES UP TO AROUND 850MB. TWO
POTENTIAL ISSUES WILL BE THE WARM GROUND AND TEMPERATURES INCREASING
TOWARD 40F. WITHOUT SOME GOOD SNOWFALL RATES IN THE BAND...IT MAY BE
HARD TO ACCUMULATE SNOW OUTSIDE OF ELEVATED SURFACES AND GRASSY
AREAS. DID INCREASE ACCUMS TO AROUND AN INCH FOR THE MORNING AND
EARLY AFTERNOON...AND WHEN ADDING THAT TO OVERNIGHT LAKE EFFECT
AMOUNTS COULD REACH AN INCH AND A HALF OR SO.

IMPROVED CONDITIONS FOR SUNDAY AS WAA IS UNDERWAY RAISING 500MB
TEMPS TO -16C AND 850MB TEMPS TO 4C AS FLOW BECOMES W/NW THROUGH THE
DAY. WITH HIGH PRESSURE OVERHEAD AND A DRY COLUMN...EXPECT A GOOD
DEAL OF SUN DURING THE DAY. HIGH TEMPS WILL RISE 5 TO 10 DEGREES
FROM SATURDAY...REACHING INTO THE MID 40S.

AN UPPER LEVEL RIDGE WILL BE IN PLACE OVER THE REGION ON MONDAY
BEFORE THE NEXT SYSTEM PUSHES THROUGH ON TUESDAY.  FRONTAL PASSAGE
WITH THIS SYSTEM WILL BRING INCREASED CHANCES FOR PRECIP OVER THE
AREA.  THE REMAINDER OF THE WEEK WILL FEATURE A CONTINUED ACTIVE
PATTERN OVER THE GREAT LAKES AS AREAS OF VORTICITY ROTATE AROUND THE
BASE OF THE UPPER LEVEL TROUGH.

MARINE...GALE FORCE WINDS HAVE SPREAD ACROSS ALL OF LAKE HURON
TODAY AND ARE WORKING THEIR WAY TOWARD LAKES ST CLAIR AND ERIE THIS
EVENING AS AN ARCTIC AIRMASS PUSHES SOUTHWARD THROUGH THE REGION.
NORTHEAST FLOW IS BEING ENHANCED BY A TIGHTENING PRESSURE GRADIENT
AS HIGH PRESSURE RUNS UP AGAINST THE SLOWLY DEPARTING LOW. THIS
COMBINED WITH UNSTABLE COLD AIR ALOFT IS LEADING TO THE WIDESPREAD
GALES. THESE CONDITIONS WILL PERSIST THROUGH TONIGHT BEFORE TAPERING
OFF THROUGH THE DAY SATURDAY AS HIGH PRESSURE BUILDS OVER THE
REGION.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR MIZ047>049-053>055-
     060>063-068>070.

     LAKESHORE FLOOD ADVISORY UNTIL NOON EDT SATURDAY FOR MIZ048-049-054-
     055-063.

LAKE HURON...GALE WARNING UNTIL NOON EDT SATURDAY FOR LHZ363-421-422-441>443-
     462>464.

     GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LHZ361.

     GALE WARNING UNTIL 2 AM EDT SATURDAY FOR LHZ362.

LAKE ST CLAIR...GALE WARNING UNTIL 10 AM EDT SATURDAY FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING UNTIL 10 AM EDT SATURDAY FOR LEZ444.

&&

$$

AVIATION.....BT
SHORT TERM...MR
LONG TERM....DRK/SS
MARINE.......DRK


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





000
FXUS63 KDTX 311956
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
356 PM EDT FRI OCT 31 2014

.SHORT TERM... THROUGH TONIGHT

POST-FRONTAL COLD AIR ADVECTION RAMPING UP WITHIN A DEEPENING
NORTHERLY FLOW AT PRESS TIME AS SE MICHIGAN SETTLES FIRMLY WITHIN
THE EASTERN PERIPHERY OF THE INBOUND HEIGHT FALLS ATTENDANT TO AN
AMPLIFYING MID LEVEL TROUGH AXIS.  MID LEVEL FORCING WITHIN THE EAST-
SOUTHEAST PIVOTING DEFORMATION AXIS AND SUBSEQUENT MAINTENANCE OF
THE EXISTING MID LEVEL FRONTAL FORCING WILL BE SLOW TO RELEASE
EASTWARD OVER THE NEXT FEW HOURS /PRIOR TO 00-02Z/...OUTSIDE OF THE
TRI-CITIES WHERE RADAR TRENDS WOULD SUGGEST THE LOSS OF BOTH THE
SYNOPTIC FORCING AND ENSUING TRAILING DRY AIR ADVECTION WILL BEGIN
TO DIMINISH CHANCES.  ELSEWHERE THE ANTECEDANT ENVIRONMENT WILL
CONTINUE TO SUPPORT SHOWER PRODUCTION THROUGH THE EVENING HOURS.
THE ADVECTIVE PROCESS WILL CONTINUE TO WORK INTO THE RESIDUAL
`WARMER` BOUNDARY LAYER...EVENTUALLY TILTING THE BULK OF THE THERMAL
PROFILE BELOW FREEZING.  THE TIMING OF THIS PROCESS CONTINUES TO
POINT TOWARD A WINDOW FOR RAIN TO MIX WITH AND/OR CHANGEOVER TO SNOW
AT LEAST AS FAR SOUTH AS THE M-59 CORRIDOR BEFORE THE DEEPER
MOISTURE STRIPS EAST.  PLACES THAT MANAGE A LONGER RESIDENCE TIME
WILL SEE SOME MINOR ACCUMULATION...CONFINED TO JUST GRASSY SURFACES
GIVEN THE WET AND RELATIVELY WARMER ROAD SURFACE CONDITIONS.

A STEADILY INCREASING WIND FIELD WILL ALSO CONTRIBUTE TO A LESS THAN
DESIRABLE CONDITION FOR THOSE WITH OUTDOOR EVENING PLANS.  RECENT
OBSERVATIONS INDICATE GUSTS AS HIGH AS 50 MPH ARE ONGOING ACROSS
PORTIONS OF THE THUMB AND INTO BAY COUNTY AS THE STRENGTHENING
GRADIENT FLOW CAPITALIZES ON THE EMERGING INSTABILITY OVER THE LAKE
HURON WATERS AND DOWN SAGINAW BAY.  PEAK GUST POTENTIAL CERTAINLY
STILL CARRIES A BIT MORE UNCERTAINTY FURTHER INLAND...MORE RELIANCE
ON SEEING SOME COMBINATION OF MIXING AND ISENTROPIC DESCENT TO
AUGMENT A FIRM WIND FIELD EMBEDDED WITHIN THE 950-850 MB LAYER.
GREATEST WINDOW FOR STRONGER GUSTS WILL EXIST 21Z-03Z...AND WILL
HOLD FIRM WITH THE WIND ADVISORY FOR LOCALES ALONG/NORTH OF THE M-59
CORRIDOR.

BOTH THE RESIDUAL TROUGHING AND DEEPER MOISTURE WILL BE SLOWER TO
EXIT ACROSS THE EASTERN THUMB...THE DEPTH SUSTAINED BY A RESPECTABLE
LOOKING LAKE RESPONSE UNDER A LONGER FETCH / 020-030 WIND
TRAJECTORY.  THIS WILL YIELD AN INCREASING COVERAGE OF LIGHT LAKE
EFFECT SNOW ACROSS THE SOUTHERN LAKE HURON BASIN...LIKELY PROVIDING
SOME RENEWED SNOW SHOWER ACTIVITY FOR THE THUMB CORRIDOR SATURDAY
MORNING.  AGAIN SOME LIGHT ACCUMULATION /HALF INCH TYPE AMOUNTS/
WILL BE PLAUSIBLE ON GRASSY SURFACES PRIOR TO 12Z.

&&

.LONG TERM...SATURDAY THROUGH THURSDAY

NOTICEABLY DIFFERENT AIRMASS THIS WEEKEND AS HIGH PRESSURE FROM
CANADA BUILDS INTO THE REGION BEHIND THE EXITING LOW PRESSURE SYSTEM.
THE AXIS OF THE MID/UPPER LEVEL TROUGH WILL BE EAST OF THE AREA BY
12Z SATURDAY BUT THE COLD POOL WILL BE SLOWER TO EXIT RESULTING IN
UNSEASONABLY COOL TEMPERATURES. VERY AMPLIFIED LONG WAVE PATTERN
WILL SET UP OVER THE CONUS BY SUNDAY WITH TROUGHS OVER BOTH COASTS
AND RIDGING BUILDING INTO THE GREAT LAKES. THIS WILL ALLOW IMPROVING
CONDITIONS BACK TO SEASONAL NORMS BY THE BEGINNING OF THE NEW WEEK.

SATURDAY WILL BE COLD WITH LAKE EFFECT SNOW SHOWERS OVER PORTIONS OF
THE THUMB WITH GOOD NE FLOW OVER LAKE HURON ON THE BACKSIDE OF THE
EXITING LOW. TEMPS AT 500MB WILL BE AROUND -28C TO START THE DAY
WITH 850MB TEMPS AROUND -9C. NE WINDS WILL STILL BE ELEVATED TO
START THE DAY DUE TO A TIGHT PRESSURE GRADIENT BETWEEN THE INCOMING
HIGH AND EXITING LOW. WINDS WILL LET UP BY SATURDAY NIGHT BUT ONLY
AFTER GUSTING TO AROUND 25 MPH IN THE AFTERNOON AGAIN. ATTENTION IS
STILL AIMED AT POTENTIAL FOR LAKE EFFECT SNOW FOR THE EASTERN THUMB
PERSISTING INTO THE DAY SATURDAY FROM OVERNIGHT ACTIVITY. THE FLOW
LOOKS TO REMAIN OUT OF THE NORTH/NORTHEAST INTO THE AFTERNOON AND
WITH RELATIVELY WARMER WATERS THE HIRES SUITE IS IN PRETTY GOOD
AGREEMENT IN DEVELOPING A FEW LAKE EFFECT BANDS OVER THE THUMB. THE
INCOMING RIDGE WILL BE VERY DRY ALOFT THUS SCOURING OUT ANY BENEFIT
TO DEEP LAYER MOISTURE PROFILES...BUT BELOW THE INVERSION SATURATION
WILL REMAIN WITH FAVORABLE LL LAPSE RATES UP TO AROUND 850MB. TWO
POTENTIAL ISSUES WILL BE THE WARM GROUND AND TEMPERATURES INCREASING
TOWARD 40F. WITHOUT SOME GOOD SNOWFALL RATES IN THE BAND...IT MAY BE
HARD TO ACCUMULATE SNOW OUTSIDE OF ELEVATED SURFACES AND GRASSY
AREAS. DID INCREASE ACCUMS TO AROUND AN INCH FOR THE MORNING AND
EARLY AFTERNOON...AND WHEN ADDING THAT TO OVERNIGHT LAKE EFFECT
AMOUNTS COULD REACH AN INCH AND A HALF OR SO.

IMPROVED CONDITIONS FOR SUNDAY AS WAA IS UNDERWAY RAISING 500MB
TEMPS TO -16C AND 850MB TEMPS TO 4C AS FLOW BECOMES W/NW THROUGH THE
DAY. WITH HIGH PRESSURE OVERHEAD AND A DRY COLUMN...EXPECT A GOOD
DEAL OF SUN DURING THE DAY. HIGH TEMPS WILL RISE 5 TO 10 DEGREES
FROM SATURDAY...REACHING INTO THE MID 40S.

AN UPPER LEVEL RIDGE WILL BE IN PLACE OVER THE REGION ON MONDAY
BEFORE THE NEXT SYSTEM PUSHES THROUGH ON TUESDAY.  FRONTAL PASSAGE
WITH THIS SYSTEM WILL BRING INCREASED CHANCES FOR PRECIP OVER THE
AREA.  THE REMAINDER OF THE WEEK WILL FEATURE A CONTINUED ACTIVE
PATTERN OVER THE GREAT LAKES AS AREAS OF VORTICITY ROTATE AROUND THE
BASE OF THE UPPER LEVEL TROUGH.

&&

.MARINE...GALE FORCE WINDS HAVE SPREAD ACROSS ALL OF LAKE HURON
TODAY AND ARE WORKING THEIR WAY TOWARD LAKES ST CLAIR AND ERIE THIS
EVENING AS AN ARCTIC AIRMASS PUSHES SOUTHWARD THROUGH THE REGION.
NORTHEAST FLOW IS BEING ENHANCED BY A TIGHTENING PRESSURE GRADIENT
AS HIGH PRESSURE RUNS UP AGAINST THE SLOWLY DEPARTING LOW. THIS
COMBINED WITH UNSTABLE COLD AIR ALOFT IS LEADING TO THE WIDESPREAD
GALES. THESE CONDITIONS WILL PERSIST THROUGH TONIGHT BEFORE TAPERING
OFF THROUGH THE DAY SATURDAY AS HIGH PRESSURE BUILDS OVER THE
REGION.

&&

.AVIATION...ISSUED 216 PM EDT FRI OCT 31 2014

//DISCUSSION...

EXTENSIVE LOW LEVEL MOISTURE WILL CONTINUE TO PIVOT ACROSS SE
MICHIGAN THROUGH THE EVENING HOURS ON THE BACKSIDE OF EXITING LOW
PRESSURE.  THIS WILL CONTINUE TO SUPPORT LOWER MVFR CEILINGS WITHIN
POCKETS OF LIGHT PRECIPITATION.  A COOLING THERMAL PROFILE AT THE
SAME TIME WILL FAVOR AN EVENTUAL TRANSITION TOWARD A RAIN/SNOW MIX.
THIS PROCESS ALREADY UNDERWAY AT MBS...WITH THE FNT/PTK CORRIDOR IN
LINE BY 21-22Z AND DTW LIKELY NOT UNTIL AFTER 00Z.  ANY ACCUMULATION
WOULD BE CONFINED TO GRASSY SURFACES.  MORE NOTABLY...NORTHERLY
WINDS WILL STRENGTHEN THROUGH THE AFTERNOON...LEADING TO GUSTS IN
EXCESS OF 30 KNOTS.  STRONGEST WINDS WILL EXIST ACROSS THE NORTHERN
TAF SITES...WHERE SOME PEAKS GUSTS WILL REACH THE 35 TO 40 KNOT
RANGE /ESPECIALLY MBS WITH FLOW DIRECTLY OFF SAGINAW BAY/.

FOR DTW...NORTHERLY WINDS WILL STRENGTHEN AFTER 21Z...PEAKING THIS
EVENING WITH GUSTS IN THE 30-32 KNOT RANGE.  ANY LINGERING RAIN
SHOWERS MAY TEND TO MIX WITH SNOW AFTER 01-02Z.  NO ACCUMULATION
EXPECTED.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FT THROUGH SATURDAY.

* HIGH CONFIDENCE IN NORTHERLY WIND GUSTS TO 30 KNOTS 21Z-03Z.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN AFTER 01Z.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR MIZ047-053-055-060>063-
     068>070.

     LAKESHORE FLOOD ADVISORY UNTIL NOON EDT SATURDAY FOR MIZ048-049-054-
     055-063.

     WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR MIZ048-049-054.

LAKE HURON...GALE WARNING UNTIL NOON EDT SATURDAY FOR LHZ363-421-422-441>443-
     462>464.

     GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LHZ361.

     GALE WARNING UNTIL 2 AM EDT SATURDAY FOR LHZ362.

LAKE ST CLAIR...GALE WARNING UNTIL 10 AM EDT SATURDAY FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING UNTIL 10 AM EDT SATURDAY FOR LEZ444.

&&

$$

SHORT TERM...MR
LONG TERM....DRK/SS
MARINE.......DRK
AVIATION.....MR


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





000
FXUS63 KDTX 311816
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
216 PM EDT FRI OCT 31 2014

.AVIATION...

//DISCUSSION...

EXTENSIVE LOW LEVEL MOISTURE WILL CONTINUE TO PIVOT ACROSS SE
MICHIGAN THROUGH THE EVENING HOURS ON THE BACKSIDE OF EXITING LOW
PRESSURE.  THIS WILL CONTINUE TO SUPPORT LOWER MVFR CEILINGS WITHIN
POCKETS OF LIGHT PRECIPITATION.  A COOLING THERMAL PROFILE AT THE
SAME TIME WILL FAVOR AN EVENTUAL TRANSITION TOWARD A RAIN/SNOW MIX.
THIS PROCESS ALREADY UNDERWAY AT MBS...WITH THE FNT/PTK CORRIDOR IN
LINE BY 21-22Z AND DTW LIKELY NOT UNTIL AFTER 00Z.  ANY ACCUMULATION
WOULD BE CONFINED TO GRASSY SURFACES.  MORE NOTABLY...NORTHERLY
WINDS WILL STRENGTHEN THROUGH THE AFTERNOON...LEADING TO GUSTS IN
EXCESS OF 30 KNOTS.  STRONGEST WINDS WILL EXIST ACROSS THE NORTHERN
TAF SITES...WHERE SOME PEAKS GUSTS WILL REACH THE 35 TO 40 KNOT
RANGE /ESPECIALLY MBS WITH FLOW DIRECTLY OFF SAGINAW BAY/.

FOR DTW...NORTHERLY WINDS WILL STRENGTHEN AFTER 21Z...PEAKING THIS
EVENING WITH GUSTS IN THE 30-32 KNOT RANGE.  ANY LINGERING RAIN
SHOWERS MAY TEND TO MIX WITH SNOW AFTER 01-02Z.  NO ACCUMULATION
EXPECTED.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5000 FT THROUGH SATURDAY.

* HIGH CONFIDENCE IN NORTHERLY WIND GUSTS TO 30 KNOTS 21Z-03Z.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN AFTER 01Z.

&&

.PREV DISCUSSION...ISSUED 1108 AM EDT FRI OCT 31 2014

UPDATE...

DYNAMIC MID LEVEL WAVE STEADILY DIGGING SOUTHEAST THIS MORNING...
RECENT WATER VAPOR SHOWING THE THE CENTER OF THIS SYSTEM NOW
ANCHORED OVER LAKE MICHIGAN. 1012 MB SURFACE LOW TIED TO THE LEAD
EDGE OF THIS HEIGHT FALL GRADIENT NOW SHIFTING ACROSS NORTH-
CENTRAL LAKE HURON...WITH THE ATTENDANT SURFACE COLD FRONTAL
BOUNDARY NOW WITHIN A COUPLE OF HOURS FROM CLEARING ALL OF
SOUTHEAST MICHIGAN TO THE SOUTHEAST. THE ENSUING COLD AIR
ADVECTION IN DEEPENING/STRENGTHENING POST-FRONTAL NORTHERLY FLOW
WILL ENSURE TEMPERATURES MOVE LITTLE OFF OF THE CURRENT LOWER 40S
READINGS...TAKING A STEADY DOWNWARD TURN BY MID-LATE AFTERNOON
INTO THE 30S FROM NORTHWEST TO SOUTHEAST. THE EXISTING MID LEVEL
FGEN ATTENDANT TO THE TRAILING ELEVATED FRONTAL ZONE MAINTAINS
SUPPORT FOR ADDITIONAL POCKETS OF PRECIPITATION TO DEVELOP THROUGH
THE EVENING. SOME AUGMENTATION IN COVERAGE IS EXPECTED AS THE
DEFORMATION AXIS CATCHES UP TO THIS FORCING AND AN INCREASINGLY
FAVORABLE TRAJECTORY BEGINS TO TAP INTO THE GROWING INSTABILITY
ACROSS LAKE HURON. GOING FORECAST HANDLING THE OVERALL ANTICIPATED
TEMPORAL AND SPATIAL TRANSITION TOWARD A RA/SN MIX AND THEN SNOW
REASONABLY WELL RELATIVE TO CURRENT OBSERVATION TRENDS UPSTREAM
AND RECENT SOUNDING DATA/THERMAL PROFILES. THE PROGRESSIVE
ADJUSTMENT TOWARD STRAIGHT ALL SNOW ACROSS NORTHERN LOWER DOES
GIVE PAUSE THAT THE ADVECTIVE COMPONENT MAY PROVE MORE FORMIDABLE
EARLY ON IN THE PROCESS TOWARD DETERIORATING THE WARMER EXISTING
BOUNDARY LAYER AND KICKING THE PTYPE TO SNOW MORE QUICKLY. SOME
MINOR ACCUMULATION REMAINS IN PLAY THIS EVENING REGARDLESS OF THE
TIMING/DURATION...CONFINED TO GRASSY SURFACES.

MAIN ADJUSTMENT WITH THIS UPDATE WILL BE NUDGE WINDS UPWARD GIVEN
RECENT TRENDS. WIND ADVISORY HAS BEEN ISSUED FOR THE M-59 CORRIDOR
NORTHWARD FROM LATE AFTERNOON THROUGH THE FIRST PART OF TONIGHT. A
SOLID INCREASE IN THE NORTH-NORTHEAST GRADIENT WILL COMMENCE
IMMEDIATELY BEHIND THE SURFACE LOW IN RESPONSE TO THE PROGRESSIVE
INTRUSION OF HIGH PRESSURE FILLING INTO THE UPPER GREAT LAKES. THE
OVERALL POSITION WILL PLACE SOUTHEAST MICHIGAN FAVORABLY FOR A
SOLID RESPONSE...THE OVERALL COMPONENT AGAIN AUGMENTED BY THE
INBOUND TRAJECTORY COMING OFF LAKE HURON. THE MIXING ELEMENT WILL
BE STUNTED SOMEWHAT BY THE HIGHER DEGREE OF MOISTURE. HOWEVER
GIVEN THIS PROCESS WILL OCCUR WITHIN THE BACKGROUND OF AT LEAST
MODEST ISENTROPIC DESCENT...A PERIOD OF GUSTS INTO THE 45 MPH
RANGE ARE PLAUSIBLE PARTICULARLY ALONG/NORTH OF M-59. POTENTIAL
IS THERE FOR LOCALES ALONG LAKE HURON SHORELINE TO SEE GUSTS IN
EXCESS OF 50 MPH...A FAVORABLE SETUP FOR A HEIGHTENED RESPONSE TO
ALIGN FROM SAGINAW BAY INTO BAY COUNTY.

PREV DISCUSSION...ISSUED 336 AM EDT FRI OCT 31 2014

SHORT TERM...TODAY AND TONIGHT

TROUGH EXTENDING FROM NORTHEAST CANADA INTO THE WESTERN GREAT
LAKES EARLY THIS MORNING WILL CONTINUE TO AMPLIFY AS A POTENT PV
ANOMALY EMBEDDED WITHIN AGGRESSIVELY DIGS TOWARD THE SOUTHERN
UNITED STATES TODAY. A WEAK 1012MB SURFACE LOW IS EVIDENT WITHIN
THE CORRIDOR OF STRONGEST HEIGHT FALLS OVER NORTHERN LAKE HURON,
BUT WITH THE BETTER DYNAMICS SHIFTING AWAY FROM THE GREAT LAKES
DURING THE FORECAST PERIOD, THE LOW WILL GRADUALLY WEAKEN AND
BECOME INCREASINGLY DISORGANIZED AS IT TRANSLATES ACROSS THE
ONTARIO PENINSULA THIS AFTERNOON.

AS OF 07Z, WIDESPREAD LIGHT SHOWERS WITH EMBEDDED MODERATE BANDING
ARE OBSERVED OVER WESTERN LOWER. THIS AREA OF RAIN IS ASSOCIATED
WITH INCREASING ISENTROPIC ASCENT IMMEDIATELY IN ADVANCE OF THE
DIGGING SHORTWAVE. THERE WILL BE PLENTY OF CONTINUED DYNAMIC SUPPORT
TO MAINTAIN THIS ACTIVITY AS THE PRE-FRONTAL CORRIDOR OF WARM
ADVECTION SHIFTS ACROSS SOUTHEAST MICHIGAN THIS MORNING.

A SECONDARY FOCUS OF PRECIPITATION WILL TAKE SHAPE OVER THE AREA
LATE THIS MORNING THROUGH ABOUT 22Z. THIS ACTIVITY WILL MAINLY BE
DRIVEN BY SFC-500MB LAYER FGEN ASSOCIATED WITH THE SYSTEM COLD
FRONT. UPSTREAM ACTIVITY OVER WISCONSIN AND THE UPPER PENINSULA IS
ALREADY EVIDENT THIS MORNING, BUT WITH MODEL PROGS INDICATING A
NOTEWORTHY TIGHTENING OF THE BAROCLINIC ZONE ALONG WITH ADDED
DAYTIME INSTABILITY, A SOLID INCREASE IN COVERAGE AND INTENSITY IS
EXPECTED, ESPECIALLY FOR FLINT AND POINTS SOUTHEAST, INCLUDING METRO
DETROIT.

IN ADDITION, A MODERATE WIND FIELD WILL BE IN PLACE AROUND THE
WEAKENING SURFACE LOW WHICH SHOULD SUPPORT WIDESPREAD SUSTAINED
WINDS OF 15 TO 20 KNOTS. DIURNAL INSTABILITY WILL SUPPORT GUSTS
INCREASING TO 25 KNOTS. AN ADDED COMPONENT OF SYSTEM RELATIVE
ISENTROPIC DESCENT ASSOCIATED WITH FROPA CENTERED WITHIN A COUPLE
HOURS EITHER SIDE OF 21Z WILL SUPPORT AN ENHANCED POP OF WIND THAT
MAY TOP OUT AS HIGH AS 35 KNOTS. THIS BAND OF ENHANCED GUSTINESS
WILL WORK SOUTHEAST FROM THE SAGINAW VALLEY AROUND 19Z TO DETROIT
METRO AROUND 23Z. IN GENERAL, HOWEVER, MARGINAL BOUNDARY LAYER
GROWTH, ONGOING PRECIP, UNIMPRESSIVE DYNAMIC SUPPORT, AND A
MARGINAL-AT-BEST SYSTEM RELATIVE SETUP PRECLUDE WIND ADVISORY
CONCERNS AT THIS TIME. THE EXCEPTION IS HURON COUNTY WHERE WINDS
COMING OFF OF LAKE HURON WILL SUPPORT GUSTS APPROACHING 40 KNOTS
ALONG THE SHORELINE. SIMILAR CONDITIONS ARE NOT OUT OF THE
QUESTION ALONG THE SOUTHERN/EASTERN SHORES OF INNER SAGINAW BAY,
BUT POTENTIAL REMAINS TOO MARGINAL TO WARRANT A SOUTHWESTWARD
EXTENSION OF THE WIND ADVISORY ATTM.

IN THE WAKE OF THE COLD FRONT, 0-1KM THETA-E LAPSE RATES OVER LAKE
HURON WILL FALL TO AROUND -6C, MODERATE VALUES, BUT IMPRESSIVE FOR
THIS TIME OF YEAR. THE THERMODYNAMIC ENVIRONMENT WILL BE SIMILAR TO
THAT OVER LAKE SUPERIOR EARLY THIS MORNING AND SHOULD YIELD AN
EQUALLY HEALTHY LAKE RESPONSE. AS A RESULT, CATEGORICAL POPS REMAIN
IN PLACE FOR THE APPROPRIATE AREAS THROUGH MOST OF THE NIGHT. AS
COLD AIR MAKES INROADS INTO THE AREA DURING THE AFTERNOON, AND
PARTICULARLY TOWARD SUNSET, A CHANGEOVER TO SNOW IS LIKELY,
ESPECIALLY THOSE AREAS WHERE BOUNDARY LAYER WET BULB TEMPERATURES
ARE FORECAST TO FALL BELOW 0C. WHILE ALL AREAS WILL BE SUBJECT TO AT
LEAST A FEW FLAKES OVERNIGHT, LOCATIONS DOWNSTREAM OF LAKE HURON MAY
SEE A FEW TENTHS OF ACCUMULATION IN SPITE OF THE ANTECEDENT WET
SURFACE. WARM ADVECTION OFF THE LAKE REMAINS A CONCERN, PARTICULARLY
OVER FAR EASTERN AREAS, WHERE LOWS MAY STRUGGLE TO FALL BELOW 35-37F
AND PTYPE WILL STRUGGLE TO CHANGE OVER. CONVERSELY, LOCATIONS WEST
OF US-23 WILL REMAIN REMOVED FROM THE LAKE PLUME AND THE COMBINATION
OF UPPER 20S LOWS AND A STOUT WIND FIELD WILL PRODUCE WIND CHILLS IN
THE UPPER TEENS BY SATURDAY MORNING.

LONG TERM...SATURDAY THROUGH THURSDAY

THE CORE OF COLDEST LOW LEVEL AIR /850MB TEMPS OF -7 TO -10C/ WILL
ROTATE ACROSS LOWER MI DURING THE DAY SATURDAY. LAKE EFFECT
PRECIPITATION IS EXPECTED TO BE ONGOING ACROSS THE SOUTHERN HALF OF
LAKE HURON SAT MORNING UNDER NORTHERLY FLOW. MODEL SOUNDINGS SUGGEST
LAKE INDUCED EQUILIBRIUM LEVELS EXCEEDING 1500 FT. EVEN WITH SOME
HEAT FLUX OFF THE LAKE...THE DEGREE OF COLD AIR /1000-850MB
THICKNESSES DROPPING BELOW 1290M/ SUGGESTS PRECIP WILL BE MAINLY IN
THE FORM OF SNOW. THERE IS SOME CONCERN THAT IF THE DEEP LAYER
SYNOPTIC MOISTURE IS A LITTLE SLOWER TO DEPART...THERE COULD BE SOME
ACCUMULATIONS ACROSS THE EASTERN THUMB. THIS WILL BE SOMETHING FOR
LATER SHIFTS TO MONITOR. LIGHTER INTENSITY SNOW SHOWERS AND/OR
FLURRIES ARE CERTAINLY POSSIBLE FARTHER INLAND. AN AGGRESSIVE PUSH OF
DRY AIR...BACKING LOW LEVEL FLOW AND LOWER INVERSION BASES DUE TO
STRENGTHENING LARGE SCALE SUBSIDENCE WILL NOT ONLY END THE LAKE
EFFECT BUT WILL SUPPORT A CLEARING TREND FROM WEST TO EAST DURING
THE AFTERNOON AND EVENING. SAT HIGHS WILL LIKELY FALL SHORT OF 40
DEGREES OVER MUCH OF THE AREA GIVEN THE DEGREE OF COLD AIR. ENOUGH
DECOUPLING IN THE BOUNDARY LAYER WITH SFC HIGH PRESSURE BUILDING IN
FROM THE WEST SAT NIGHT WILL DROP LOWS WELL DOWN INTO THE 20S.

ALTHOUGH AMPLIFIED...THE LARGE SCALE PATTERN WILL REMAIN PROGRESSIVE
WITH MID LEVEL RIDGING EXPANDING ACROSS THE GREAT LAKES BY THE
END OF THE WEEKEND. THIS AND THE DEPARTURE OF THE SFC HIGH TO THE
EAST WILL ESTABLISH A WARM AIR ADVECTION REGIME ACROSS LOWER
MI...LEADING TO A MODEST WARMING TREND HEADING INTO EARLY NEXT
WEEK. MOIST ADVECTION WILL THEN INCREASE MON NIGHT INTO TUES IN
ADVANCE OF A LONG WAVE TROUGH...SUPPORTING THE NEXT CHANCE FOR
PRECIP /WARM ENOUGH FOR ALL RAIN WITH THIS SYSTEM/. THE MEDIUM
RANGE MODEL SUITE SUGGEST THE NORTHERN STREAM WILL REMAIN
PROGRESSIVE THROUGH NEXT WEEK...WITH THE NEXT MID LEVEL WAVE AND
SHOT AT SOME COLDER AIR ARRIVING LATE IN THE FORECAST PERIOD.

MARINE...GALE WARNINGS REMAIN IN EFFECT FOR ALL MARINE AREAS TODAY
INTO TONIGHT. A PUSH OF ARCTIC AIR WILL CONTINUE TO FUNNEL INTO THE
REGION BEHIND A COLD FRONT ASSOCIATED WITH A LOW PRESSURE SYSTEM
FORECAST TO MOVE FROM NORTHERN LAKE HURON THIS MORNING INTO THE
UPPER OHIO VALLEY BY EVENING. HIGH PRESSURE NUDGING INTO THE WESTERN
GREAT LAKES FROM THE PLAINS WILL SUSTAIN A TIGHT PRESSURE GRADIENT
ALONG THE BACK SIDE OF THE DEPARTING LOW. THIS COMBINED WITH THE
HIGHLY UNSTABLE CONDITIONS OVER THE MARINE AREAS WILL SUPPORT GALE
FORCE WINDS DEVELOPING OVER NORTHERN LAKE HURON THIS MORNING AND THE
SOUTHERN HALF OF THE LAKE BY AFTERNOON. WINDS AND WAVES WILL SLOWLY
DECREASE SATURDAY INTO SATURDAY NIGHT AS HIGH PRESSURE BUILDS IN
FROM THE WEST.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR MIZ047-053-055-060>063-
     068>070.

     LAKESHORE FLOOD ADVISORY UNTIL NOON EDT SATURDAY FOR MIZ048-049-054-
     055-063.

     WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR MIZ048-049-054.

LAKE HURON...GALE WARNING UNTIL NOON EDT SATURDAY FOR LHZ363-421-422-441>443-
     462>464.

     GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LHZ361.

     GALE WARNING UNTIL 2 AM EDT SATURDAY FOR LHZ362.

LAKE ST CLAIR...GALE WARNING UNTIL 10 AM EDT SATURDAY FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING UNTIL 10 AM EDT SATURDAY FOR LEZ444.

&&

$$

AVIATION.....MR
UPDATE.......MR
SHORT TERM...JVC
LONG TERM....SC
MARINE.......SC


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





000
FXUS63 KDTX 311508
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1108 AM EDT FRI OCT 31 2014

.UPDATE...

DYNAMIC MID LEVEL WAVE STEADILY DIGGING SOUTHEAST THIS MORNING...
RECENT WATER VAPOR SHOWING THE THE CENTER OF THIS SYSTEM NOW
ANCHORED OVER LAKE MICHIGAN. 1012 MB SURFACE LOW TIED TO THE LEAD
EDGE OF THIS HEIGHT FALL GRADIENT NOW SHIFTING ACROSS NORTH-
CENTRAL LAKE HURON...WITH THE ATTENDANT SURFACE COLD FRONTAL
BOUNDARY NOW WITHIN A COUPLE OF HOURS FROM CLEARING ALL OF
SOUTHEAST MICHIGAN TO THE SOUTHEAST. THE ENSUING COLD AIR
ADVECTION IN DEEPENING/STRENGTHENING POST-FRONTAL NORTHERLY FLOW
WILL ENSURE TEMPERATURES MOVE LITTLE OFF OF THE CURRENT LOWER 40S
READINGS...TAKING A STEADY DOWNWARD TURN BY MID-LATE AFTERNOON
INTO THE 30S FROM NORTHWEST TO SOUTHEAST. THE EXISTING MID LEVEL
FGEN ATTENDANT TO THE TRAILING ELEVATED FRONTAL ZONE MAINTAINS
SUPPORT FOR ADDITIONAL POCKETS OF PRECIPITATION TO DEVELOP THROUGH
THE EVENING. SOME AUGMENTATION IN COVERAGE IS EXPECTED AS THE
DEFORMATION AXIS CATCHES UP TO THIS FORCING AND AN INCREASINGLY
FAVORABLE TRAJECTORY BEGINS TO TAP INTO THE GROWING INSTABILITY
ACROSS LAKE HURON. GOING FORECAST HANDLING THE OVERALL ANTICIPATED
TEMPORAL AND SPATIAL TRANSITION TOWARD A RA/SN MIX AND THEN SNOW
REASONABLY WELL RELATIVE TO CURRENT OBSERVATION TRENDS UPSTREAM
AND RECENT SOUNDING DATA/THERMAL PROFILES. THE PROGRESSIVE
ADJUSTMENT TOWARD STRAIGHT ALL SNOW ACROSS NORTHERN LOWER DOES
GIVE PAUSE THAT THE ADVECTIVE COMPONENT MAY PROVE MORE FORMIDABLE
EARLY ON IN THE PROCESS TOWARD DETERIORATING THE WARMER EXISTING
BOUNDARY LAYER AND KICKING THE PTYPE TO SNOW MORE QUICKLY. SOME
MINOR ACCUMULATION REMAINS IN PLAY THIS EVENING REGARDLESS OF THE
TIMING/DURATION...CONFINED TO GRASSY SURFACES.

MAIN ADJUSTMENT WITH THIS UPDATE WILL BE NUDGE WINDS UPWARD GIVEN
RECENT TRENDS. WIND ADVISORY HAS BEEN ISSUED FOR THE M-59 CORRIDOR
NORTHWARD FROM LATE AFTERNOON THROUGH THE FIRST PART OF TONIGHT. A
SOLID INCREASE IN THE NORTH-NORTHEAST GRADIENT WILL COMMENCE
IMMEDIATELY BEHIND THE SURFACE LOW IN RESPONSE TO THE PROGRESSIVE
INTRUSION OF HIGH PRESSURE FILLING INTO THE UPPER GREAT LAKES. THE
OVERALL POSITION WILL PLACE SOUTHEAST MICHIGAN FAVORABLY FOR A
SOLID RESPONSE...THE OVERALL COMPONENT AGAIN AUGMENTED BY THE
INBOUND TRAJECTORY COMING OFF LAKE HURON. THE MIXING ELEMENT WILL
BE STUNTED SOMEWHAT BY THE HIGHER DEGREE OF MOISTURE. HOWEVER
GIVEN THIS PROCESS WILL OCCUR WITHIN THE BACKGROUND OF AT LEAST
MODEST ISENTROPIC DESCENT...A PERIOD OF GUSTS INTO THE 45 MPH
RANGE ARE PLAUSIBLE PARTICULARLY ALONG/NORTH OF M-59. POTENTIAL
IS THERE FOR LOCALES ALONG LAKE HURON SHORELINE TO SEE GUSTS IN
EXCESS OF 50 MPH...A FAVORABLE SETUP FOR A HEIGHTENED RESPONSE TO
ALIGN FROM SAGINAW BAY INTO BAY COUNTY.

&&

.AVIATION...ISSUED 700 AM EDT FRI OCT 31 2014

//DISCUSSION...

VERY FEW ADJUSTMENTS NEEDED TO THE PREVIOUS FORECAST. MVFR
CONDITIONS ASSOCIATED WITH LIGHT PREFRONTAL RAINFALL HAVE OVERSPREAD
THE AREA THIS MORNING. SOUTHWESTERLY WINDS WILL SLOWLY VEER THROUGH
THE DAY UNTIL THE PASSAGE OF THE COLD FRONT THIS MORNING THROUGH
AFTERNOON. IN THE MEANTIME...MVFR CIGS AND PERHAPS A LIGHT FOG
RESTRICTION WILL HOLD BETWEEN THE PREFRONTAL RAIN AND THE COLD FRONT
ITSELF. HIGHER RAINFALL RATES AND A SHIFT TO NORTHERLY WINDS CAN
THEN BE EXPECTED WITH FROPA ALONG WITH DEVELOPING WIND GUSTS TO 30
KNOTS. THE FRONT WILL PASS KMBS AROUND 15Z AND KDTW AROUND 20Z. COLD
ADVECTION WILL KEEP THE BOUNDARY LAYER WELL MIXED THROUGH THE NIGHT
RESULTING IN PERSISTENCE OF BOTH LOW CLOUDS AND WIND GUSTS TO 25
KNOTS OR HIGHER. RAIN SHOWERS WILL MIX WITH AND POSSIBLY CHANGE OVER
TO SNOW AS COLD AIR INFILTRATES FROM NW TO SE THIS AFTERNOON INTO
THIS EVENING.


FOR DTW...WINDS WILL GRADUALLY VEER THROUGH THE DAY, BUT A MORE
CONCERTED TURN TO NORTHERLY WINDS CAN BE EXPECTED WITH COLD FRONTAL
PASSAGE AROUND 20Z. MIXING OF LINGERING RAIN SHOWERS WITH SNOW WILL
BE POSSIBLE AFTER 01Z. NO ACCUMULATION.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5KFT

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN AFTER 01Z.

&&

.PREV DISCUSSION...ISSUED 336 AM EDT FRI OCT 31 2014

SHORT TERM...TODAY AND TONIGHT

TROUGH EXTENDING FROM NORTHEAST CANADA INTO THE WESTERN GREAT
LAKES EARLY THIS MORNING WILL CONTINUE TO AMPLIFY AS A POTENT PV
ANOMALY EMBEDDED WITHIN AGGRESSIVELY DIGS TOWARD THE SOUTHERN
UNITED STATES TODAY. A WEAK 1012MB SURFACE LOW IS EVIDENT WITHIN
THE CORRIDOR OF STRONGEST HEIGHT FALLS OVER NORTHERN LAKE HURON,
BUT WITH THE BETTER DYNAMICS SHIFTING AWAY FROM THE GREAT LAKES
DURING THE FORECAST PERIOD, THE LOW WILL GRADUALLY WEAKEN AND
BECOME INCREASINGLY DISORGANIZED AS IT TRANSLATES ACROSS THE
ONTARIO PENINSULA THIS AFTERNOON.

AS OF 07Z, WIDESPREAD LIGHT SHOWERS WITH EMBEDDED MODERATE BANDING
ARE OBSERVED OVER WESTERN LOWER. THIS AREA OF RAIN IS ASSOCIATED
WITH INCREASING ISENTROPIC ASCENT IMMEDIATELY IN ADVANCE OF THE
DIGGING SHORTWAVE. THERE WILL BE PLENTY OF CONTINUED DYNAMIC SUPPORT
TO MAINTAIN THIS ACTIVITY AS THE PRE-FRONTAL CORRIDOR OF WARM
ADVECTION SHIFTS ACROSS SOUTHEAST MICHIGAN THIS MORNING.

A SECONDARY FOCUS OF PRECIPITATION WILL TAKE SHAPE OVER THE AREA
LATE THIS MORNING THROUGH ABOUT 22Z. THIS ACTIVITY WILL MAINLY BE
DRIVEN BY SFC-500MB LAYER FGEN ASSOCIATED WITH THE SYSTEM COLD
FRONT. UPSTREAM ACTIVITY OVER WISCONSIN AND THE UPPER PENINSULA IS
ALREADY EVIDENT THIS MORNING, BUT WITH MODEL PROGS INDICATING A
NOTEWORTHY TIGHTENING OF THE BAROCLINIC ZONE ALONG WITH ADDED
DAYTIME INSTABILITY, A SOLID INCREASE IN COVERAGE AND INTENSITY IS
EXPECTED, ESPECIALLY FOR FLINT AND POINTS SOUTHEAST, INCLUDING METRO
DETROIT.

IN ADDITION, A MODERATE WIND FIELD WILL BE IN PLACE AROUND THE
WEAKENING SURFACE LOW WHICH SHOULD SUPPORT WIDESPREAD SUSTAINED
WINDS OF 15 TO 20 KNOTS. DIURNAL INSTABILITY WILL SUPPORT GUSTS
INCREASING TO 25 KNOTS. AN ADDED COMPONENT OF SYSTEM RELATIVE
ISENTROPIC DESCENT ASSOCIATED WITH FROPA CENTERED WITHIN A COUPLE
HOURS EITHER SIDE OF 21Z WILL SUPPORT AN ENHANCED POP OF WIND THAT
MAY TOP OUT AS HIGH AS 35 KNOTS. THIS BAND OF ENHANCED GUSTINESS
WILL WORK SOUTHEAST FROM THE SAGINAW VALLEY AROUND 19Z TO DETROIT
METRO AROUND 23Z. IN GENERAL, HOWEVER, MARGINAL BOUNDARY LAYER
GROWTH, ONGOING PRECIP, UNIMPRESSIVE DYNAMIC SUPPORT, AND A
MARGINAL-AT-BEST SYSTEM RELATIVE SETUP PRECLUDE WIND ADVISORY
CONCERNS AT THIS TIME. THE EXCEPTION IS HURON COUNTY WHERE WINDS
COMING OFF OF LAKE HURON WILL SUPPORT GUSTS APPROACHING 40 KNOTS
ALONG THE SHORELINE. SIMILAR CONDITIONS ARE NOT OUT OF THE
QUESTION ALONG THE SOUTHERN/EASTERN SHORES OF INNER SAGINAW BAY,
BUT POTENTIAL REMAINS TOO MARGINAL TO WARRANT A SOUTHWESTWARD
EXTENSION OF THE WIND ADVISORY ATTM.

IN THE WAKE OF THE COLD FRONT, 0-1KM THETA-E LAPSE RATES OVER LAKE
HURON WILL FALL TO AROUND -6C, MODERATE VALUES, BUT IMPRESSIVE FOR
THIS TIME OF YEAR. THE THERMODYNAMIC ENVIRONMENT WILL BE SIMILAR TO
THAT OVER LAKE SUPERIOR EARLY THIS MORNING AND SHOULD YIELD AN
EQUALLY HEALTHY LAKE RESPONSE. AS A RESULT, CATEGORICAL POPS REMAIN
IN PLACE FOR THE APPROPRIATE AREAS THROUGH MOST OF THE NIGHT. AS
COLD AIR MAKES INROADS INTO THE AREA DURING THE AFTERNOON, AND
PARTICULARLY TOWARD SUNSET, A CHANGEOVER TO SNOW IS LIKELY,
ESPECIALLY THOSE AREAS WHERE BOUNDARY LAYER WET BULB TEMPERATURES
ARE FORECAST TO FALL BELOW 0C. WHILE ALL AREAS WILL BE SUBJECT TO AT
LEAST A FEW FLAKES OVERNIGHT, LOCATIONS DOWNSTREAM OF LAKE HURON MAY
SEE A FEW TENTHS OF ACCUMULATION IN SPITE OF THE ANTECEDENT WET
SURFACE. WARM ADVECTION OFF THE LAKE REMAINS A CONCERN, PARTICULARLY
OVER FAR EASTERN AREAS, WHERE LOWS MAY STRUGGLE TO FALL BELOW 35-37F
AND PTYPE WILL STRUGGLE TO CHANGE OVER. CONVERSELY, LOCATIONS WEST
OF US-23 WILL REMAIN REMOVED FROM THE LAKE PLUME AND THE COMBINATION
OF UPPER 20S LOWS AND A STOUT WIND FIELD WILL PRODUCE WIND CHILLS IN
THE UPPER TEENS BY SATURDAY MORNING.

LONG TERM...SATURDAY THROUGH THURSDAY

THE CORE OF COLDEST LOW LEVEL AIR /850MB TEMPS OF -7 TO -10C/ WILL
ROTATE ACROSS LOWER MI DURING THE DAY SATURDAY. LAKE EFFECT
PRECIPITATION IS EXPECTED TO BE ONGOING ACROSS THE SOUTHERN HALF OF
LAKE HURON SAT MORNING UNDER NORTHERLY FLOW. MODEL SOUNDINGS SUGGEST
LAKE INDUCED EQUILIBRIUM LEVELS EXCEEDING 1500 FT. EVEN WITH SOME
HEAT FLUX OFF THE LAKE...THE DEGREE OF COLD AIR /1000-850MB
THICKNESSES DROPPING BELOW 1290M/ SUGGESTS PRECIP WILL BE MAINLY IN
THE FORM OF SNOW. THERE IS SOME CONCERN THAT IF THE DEEP LAYER
SYNOPTIC MOISTURE IS A LITTLE SLOWER TO DEPART...THERE COULD BE SOME
ACCUMULATIONS ACROSS THE EASTERN THUMB. THIS WILL BE SOMETHING FOR
LATER SHIFTS TO MONITOR. LIGHTER INTENSITY SNOW SHOWERS AND/OR
FLURRIES ARE CERTAINLY POSSIBLE FARTHER INLAND. AN AGGRESSIVE PUSH OF
DRY AIR...BACKING LOW LEVEL FLOW AND LOWER INVERSION BASES DUE TO
STRENGTHENING LARGE SCALE SUBSIDENCE WILL NOT ONLY END THE LAKE
EFFECT BUT WILL SUPPORT A CLEARING TREND FROM WEST TO EAST DURING
THE AFTERNOON AND EVENING. SAT HIGHS WILL LIKELY FALL SHORT OF 40
DEGREES OVER MUCH OF THE AREA GIVEN THE DEGREE OF COLD AIR. ENOUGH
DECOUPLING IN THE BOUNDARY LAYER WITH SFC HIGH PRESSURE BUILDING IN
FROM THE WEST SAT NIGHT WILL DROP LOWS WELL DOWN INTO THE 20S.

ALTHOUGH AMPLIFIED...THE LARGE SCALE PATTERN WILL REMAIN PROGRESSIVE
WITH MID LEVEL RIDGING EXPANDING ACROSS THE GREAT LAKES BY THE
END OF THE WEEKEND. THIS AND THE DEPARTURE OF THE SFC HIGH TO THE
EAST WILL ESTABLISH A WARM AIR ADVECTION REGIME ACROSS LOWER
MI...LEADING TO A MODEST WARMING TREND HEADING INTO EARLY NEXT
WEEK. MOIST ADVECTION WILL THEN INCREASE MON NIGHT INTO TUES IN
ADVANCE OF A LONG WAVE TROUGH...SUPPORTING THE NEXT CHANCE FOR
PRECIP /WARM ENOUGH FOR ALL RAIN WITH THIS SYSTEM/. THE MEDIUM
RANGE MODEL SUITE SUGGEST THE NORTHERN STREAM WILL REMAIN
PROGRESSIVE THROUGH NEXT WEEK...WITH THE NEXT MID LEVEL WAVE AND
SHOT AT SOME COLDER AIR ARRIVING LATE IN THE FORECAST PERIOD.

MARINE...GALE WARNINGS REMAIN IN EFFECT FOR ALL MARINE AREAS TODAY
INTO TONIGHT. A PUSH OF ARCTIC AIR WILL CONTINUE TO FUNNEL INTO THE
REGION BEHIND A COLD FRONT ASSOCIATED WITH A LOW PRESSURE SYSTEM
FORECAST TO MOVE FROM NORTHERN LAKE HURON THIS MORNING INTO THE
UPPER OHIO VALLEY BY EVENING. HIGH PRESSURE NUDGING INTO THE WESTERN
GREAT LAKES FROM THE PLAINS WILL SUSTAIN A TIGHT PRESSURE GRADIENT
ALONG THE BACK SIDE OF THE DEPARTING LOW. THIS COMBINED WITH THE
HIGHLY UNSTABLE CONDITIONS OVER THE MARINE AREAS WILL SUPPORT GALE
FORCE WINDS DEVELOPING OVER NORTHERN LAKE HURON THIS MORNING AND THE
SOUTHERN HALF OF THE LAKE BY AFTERNOON. WINDS AND WAVES WILL SLOWLY
DECREASE SATURDAY INTO SATURDAY NIGHT AS HIGH PRESSURE BUILDS IN
FROM THE WEST.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY FROM 4 PM THIS AFTERNOON TO MIDNIGHT EDT TONIGHT FOR
     MIZ047>049-053>055-060>063-068>070.

LAKE HURON...GALE WARNING UNTIL NOON EDT SATURDAY FOR LHZ363-421-422-441>443-
     462>464.

     GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LHZ361.

     GALE WARNING UNTIL 2 AM EDT SATURDAY FOR LHZ362.

LAKE ST CLAIR...GALE WARNING FROM 6 PM THIS EVENING TO 10 AM EDT SATURDAY FOR
     LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING FROM 6 PM THIS EVENING TO 10 AM EDT SATURDAY FOR
     LEZ444.

&&

$$

UPDATE.......MR
AVIATION.....JVC
SHORT TERM...JVC
LONG TERM....SC
MARINE.......SC


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





000
FXUS63 KDTX 311100
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
700 AM EDT FRI OCT 31 2014


.AVIATION...

//DISCUSSION...

VERY FEW ADJUSTMENTS NEEDED TO THE PREVIOUS FORECAST. MVFR
CONDITIONS ASSOCIATED WITH LIGHT PREFRONTAL RAINFALL HAVE OVERSPREAD
THE AREA THIS MORNING. SOUTHWESTERLY WINDS WILL SLOWLY VEER THROUGH
THE DAY UNTIL THE PASSAGE OF THE COLD FRONT THIS MORNING THROUGH
AFTERNOON. IN THE MEANTIME...MVFR CIGS AND PERHAPS A LIGHT FOG
RESTRICTION WILL HOLD BETWEEN THE PREFRONTAL RAIN AND THE COLD FRONT
ITSELF. HIGHER RAINFALL RATES AND A SHIFT TO NORTHERLY WINDS CAN
THEN BE EXPECTED WITH FROPA ALONG WITH DEVELOPING WIND GUSTS TO 30
KNOTS. THE FRONT WILL PASS KMBS AROUND 15Z AND KDTW AROUND 20Z. COLD
ADVECTION WILL KEEP THE BOUNDARY LAYER WELL MIXED THROUGH THE NIGHT
RESULTING IN PERSISTENCE OF BOTH LOW CLOUDS AND WIND GUSTS TO 25
KNOTS OR HIGHER. RAIN SHOWERS WILL MIX WITH AND POSSIBLY CHANGE OVER
TO SNOW AS COLD AIR INFILTRATES FROM NW TO SE THIS AFTERNOON INTO
THIS EVENING.


FOR DTW...WINDS WILL GRADUALLY VEER THROUGH THE DAY, BUT A MORE
CONCERTED TURN TO NORTHERLY WINDS CAN BE EXPECTED WITH COLD FRONTAL
PASSAGE AROUND 20Z. MIXING OF LINGERING RAIN SHOWERS WITH SNOW WILL
BE POSSIBLE AFTER 01Z. NO ACCUMULATION.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5KFT

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN AFTER 01Z.

&&

.PREV DISCUSSION...ISSUED 336 AM EDT FRI OCT 31 2014

SHORT TERM...TODAY AND TONIGHT

TROUGH EXTENDING FROM NORTHEAST CANADA INTO THE WESTERN GREAT
LAKES EARLY THIS MORNING WILL CONTINUE TO AMPLIFY AS A POTENT PV
ANOMALY EMBEDDED WITHIN AGGRESSIVELY DIGS TOWARD THE SOUTHERN
UNITED STATES TODAY. A WEAK 1012MB SURFACE LOW IS EVIDENT WITHIN
THE CORRIDOR OF STRONGEST HEIGHT FALLS OVER NORTHERN LAKE HURON,
BUT WITH THE BETTER DYNAMICS SHIFTING AWAY FROM THE GREAT LAKES
DURING THE FORECAST PERIOD, THE LOW WILL GRADUALLY WEAKEN AND
BECOME INCREASINGLY DISORGANIZED AS IT TRANSLATES ACROSS THE
ONTARIO PENINSULA THIS AFTERNOON.

AS OF 07Z, WIDESPREAD LIGHT SHOWERS WITH EMBEDDED MODERATE BANDING
ARE OBSERVED OVER WESTERN LOWER. THIS AREA OF RAIN IS ASSOCIATED
WITH INCREASING ISENTROPIC ASCENT IMMEDIATELY IN ADVANCE OF THE
DIGGING SHORTWAVE. THERE WILL BE PLENTY OF CONTINUED DYNAMIC SUPPORT
TO MAINTAIN THIS ACTIVITY AS THE PRE-FRONTAL CORRIDOR OF WARM
ADVECTION SHIFTS ACROSS SOUTHEAST MICHIGAN THIS MORNING.

A SECONDARY FOCUS OF PRECIPITATION WILL TAKE SHAPE OVER THE AREA
LATE THIS MORNING THROUGH ABOUT 22Z. THIS ACTIVITY WILL MAINLY BE
DRIVEN BY SFC-500MB LAYER FGEN ASSOCIATED WITH THE SYSTEM COLD
FRONT. UPSTREAM ACTIVITY OVER WISCONSIN AND THE UPPER PENINSULA IS
ALREADY EVIDENT THIS MORNING, BUT WITH MODEL PROGS INDICATING A
NOTEWORTHY TIGHTENING OF THE BAROCLINIC ZONE ALONG WITH ADDED
DAYTIME INSTABILITY, A SOLID INCREASE IN COVERAGE AND INTENSITY IS
EXPECTED, ESPECIALLY FOR FLINT AND POINTS SOUTHEAST, INCLUDING METRO
DETROIT.

IN ADDITION, A MODERATE WIND FIELD WILL BE IN PLACE AROUND THE
WEAKENING SURFACE LOW WHICH SHOULD SUPPORT WIDESPREAD SUSTAINED
WINDS OF 15 TO 20 KNOTS. DIURNAL INSTABILITY WILL SUPPORT GUSTS
INCREASING TO 25 KNOTS. AN ADDED COMPONENT OF SYSTEM RELATIVE
ISENTROPIC DESCENT ASSOCIATED WITH FROPA CENTERED WITHIN A COUPLE
HOURS EITHER SIDE OF 21Z WILL SUPPORT AN ENHANCED POP OF WIND THAT
MAY TOP OUT AS HIGH AS 35 KNOTS. THIS BAND OF ENHANCED GUSTINESS
WILL WORK SOUTHEAST FROM THE SAGINAW VALLEY AROUND 19Z TO DETROIT
METRO AROUND 23Z. IN GENERAL, HOWEVER, MARGINAL BOUNDARY LAYER
GROWTH, ONGOING PRECIP, UNIMPRESSIVE DYNAMIC SUPPORT, AND A
MARGINAL-AT-BEST SYSTEM RELATIVE SETUP PRECLUDE WIND ADVISORY
CONCERNS AT THIS TIME. THE EXCEPTION IS HURON COUNTY WHERE WINDS
COMING OFF OF LAKE HURON WILL SUPPORT GUSTS APPROACHING 40 KNOTS
ALONG THE SHORELINE. SIMILAR CONDITIONS ARE NOT OUT OF THE
QUESTION ALONG THE SOUTHERN/EASTERN SHORES OF INNER SAGINAW BAY,
BUT POTENTIAL REMAINS TOO MARGINAL TO WARRANT A SOUTHWESTWARD
EXTENSION OF THE WIND ADVISORY ATTM.

IN THE WAKE OF THE COLD FRONT, 0-1KM THETA-E LAPSE RATES OVER LAKE
HURON WILL FALL TO AROUND -6C, MODERATE VALUES, BUT IMPRESSIVE FOR
THIS TIME OF YEAR. THE THERMODYNAMIC ENVIRONMENT WILL BE SIMILAR TO
THAT OVER LAKE SUPERIOR EARLY THIS MORNING AND SHOULD YIELD AN
EQUALLY HEALTHY LAKE RESPONSE. AS A RESULT, CATEGORICAL POPS REMAIN
IN PLACE FOR THE APPROPRIATE AREAS THROUGH MOST OF THE NIGHT. AS
COLD AIR MAKES INROADS INTO THE AREA DURING THE AFTERNOON, AND
PARTICULARLY TOWARD SUNSET, A CHANGEOVER TO SNOW IS LIKELY,
ESPECIALLY THOSE AREAS WHERE BOUNDARY LAYER WET BULB TEMPERATURES
ARE FORECAST TO FALL BELOW 0C. WHILE ALL AREAS WILL BE SUBJECT TO AT
LEAST A FEW FLAKES OVERNIGHT, LOCATIONS DOWNSTREAM OF LAKE HURON MAY
SEE A FEW TENTHS OF ACCUMULATION IN SPITE OF THE ANTECEDENT WET
SURFACE. WARM ADVECTION OFF THE LAKE REMAINS A CONCERN, PARTICULARLY
OVER FAR EASTERN AREAS, WHERE LOWS MAY STRUGGLE TO FALL BELOW 35-37F
AND PTYPE WILL STRUGGLE TO CHANGE OVER. CONVERSELY, LOCATIONS WEST
OF US-23 WILL REMAIN REMOVED FROM THE LAKE PLUME AND THE COMBINATION
OF UPPER 20S LOWS AND A STOUT WIND FIELD WILL PRODUCE WIND CHILLS IN
THE UPPER TEENS BY SATURDAY MORNING.

LONG TERM...SATURDAY THROUGH THURSDAY

THE CORE OF COLDEST LOW LEVEL AIR /850MB TEMPS OF -7 TO -10C/ WILL
ROTATE ACROSS LOWER MI DURING THE DAY SATURDAY. LAKE EFFECT
PRECIPITATION IS EXPECTED TO BE ONGOING ACROSS THE SOUTHERN HALF OF
LAKE HURON SAT MORNING UNDER NORTHERLY FLOW. MODEL SOUNDINGS SUGGEST
LAKE INDUCED EQUILIBRIUM LEVELS EXCEEDING 1500 FT. EVEN WITH SOME
HEAT FLUX OFF THE LAKE...THE DEGREE OF COLD AIR /1000-850MB
THICKNESSES DROPPING BELOW 1290M/ SUGGESTS PRECIP WILL BE MAINLY IN
THE FORM OF SNOW. THERE IS SOME CONCERN THAT IF THE DEEP LAYER
SYNOPTIC MOISTURE IS A LITTLE SLOWER TO DEPART...THERE COULD BE SOME
ACCUMULATIONS ACROSS THE EASTERN THUMB. THIS WILL BE SOMETHING FOR
LATER SHIFTS TO MONITOR. LIGHTER INTENSITY SNOW SHOWERS AND/OR
FLURRIES ARE CERTAINLY POSSIBLE FARTHER INLAND. AN AGGRESSIVE PUSH OF
DRY AIR...BACKING LOW LEVEL FLOW AND LOWER INVERSION BASES DUE TO
STRENGTHENING LARGE SCALE SUBSIDENCE WILL NOT ONLY END THE LAKE
EFFECT BUT WILL SUPPORT A CLEARING TREND FROM WEST TO EAST DURING
THE AFTERNOON AND EVENING. SAT HIGHS WILL LIKELY FALL SHORT OF 40
DEGREES OVER MUCH OF THE AREA GIVEN THE DEGREE OF COLD AIR. ENOUGH
DECOUPLING IN THE BOUNDARY LAYER WITH SFC HIGH PRESSURE BUILDING IN
FROM THE WEST SAT NIGHT WILL DROP LOWS WELL DOWN INTO THE 20S.

ALTHOUGH AMPLIFIED...THE LARGE SCALE PATTERN WILL REMAIN PROGRESSIVE
WITH MID LEVEL RIDGING EXPANDING ACROSS THE GREAT LAKES BY THE
END OF THE WEEKEND. THIS AND THE DEPARTURE OF THE SFC HIGH TO THE
EAST WILL ESTABLISH A WARM AIR ADVECTION REGIME ACROSS LOWER
MI...LEADING TO A MODEST WARMING TREND HEADING INTO EARLY NEXT
WEEK. MOIST ADVECTION WILL THEN INCREASE MON NIGHT INTO TUES IN
ADVANCE OF A LONG WAVE TROUGH...SUPPORTING THE NEXT CHANCE FOR
PRECIP /WARM ENOUGH FOR ALL RAIN WITH THIS SYSTEM/. THE MEDIUM
RANGE MODEL SUITE SUGGEST THE NORTHERN STREAM WILL REMAIN
PROGRESSIVE THROUGH NEXT WEEK...WITH THE NEXT MID LEVEL WAVE AND
SHOT AT SOME COLDER AIR ARRIVING LATE IN THE FORECAST PERIOD.

MARINE...GALE WARNINGS REMAIN IN EFFECT FOR ALL MARINE AREAS TODAY
INTO TONIGHT. A PUSH OF ARCTIC AIR WILL CONTINUE TO FUNNEL INTO THE
REGION BEHIND A COLD FRONT ASSOCIATED WITH A LOW PRESSURE SYSTEM
FORECAST TO MOVE FROM NORTHERN LAKE HURON THIS MORNING INTO THE
UPPER OHIO VALLEY BY EVENING. HIGH PRESSURE NUDGING INTO THE WESTERN
GREAT LAKES FROM THE PLAINS WILL SUSTAIN A TIGHT PRESSURE GRADIENT
ALONG THE BACK SIDE OF THE DEPARTING LOW. THIS COMBINED WITH THE
HIGHLY UNSTABLE CONDITIONS OVER THE MARINE AREAS WILL SUPPORT GALE
FORCE WINDS DEVELOPING OVER NORTHERN LAKE HURON THIS MORNING AND THE
SOUTHERN HALF OF THE LAKE BY AFTERNOON. WINDS AND WAVES WILL SLOWLY
DECREASE SATURDAY INTO SATURDAY NIGHT AS HIGH PRESSURE BUILDS IN
FROM THE WEST.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 10 PM EDT THIS EVENING
     FOR MIZ049.

LAKE HURON...GALE WARNING FROM 1 PM THIS AFTERNOON TO NOON EDT SATURDAY FOR
     LHZ363-441-462>464.

     GALE WARNING FROM 2 PM THIS AFTERNOON TO NOON EDT SATURDAY FOR
     LHZ442-443.

     GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LHZ361.

     GALE WARNING UNTIL 2 AM EDT SATURDAY FOR LHZ362.

     GALE WARNING FROM 1 PM THIS AFTERNOON TO 5 AM EDT SATURDAY FOR
     LHZ421-422.

LAKE ST CLAIR...GALE WARNING FROM 6 PM THIS EVENING TO 10 AM EDT SATURDAY FOR
     LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING FROM 6 PM THIS EVENING TO 10 AM EDT SATURDAY FOR
     LEZ444.

&&

$$

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


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





000
FXUS63 KDTX 310736
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
336 AM EDT FRI OCT 31 2014

.SHORT TERM...TODAY AND TONIGHT

TROUGH EXTENDING FROM NORTHEAST CANADA INTO THE WESTERN GREAT
LAKES EARLY THIS MORNING WILL CONTINUE TO AMPLIFY AS A POTENT PV
ANOMALY EMBEDDED WITHIN AGGRESSIVELY DIGS TOWARD THE SOUTHERN
UNITED STATES TODAY. A WEAK 1012MB SURFACE LOW IS EVIDENT WITHIN
THE CORRIDOR OF STRONGEST HEIGHT FALLS OVER NORTHERN LAKE HURON,
BUT WITH THE BETTER DYNAMICS SHIFTING AWAY FROM THE GREAT LAKES
DURING THE FORECAST PERIOD, THE LOW WILL GRADUALLY WEAKEN AND
BECOME INCREASINGLY DISORGANIZED AS IT TRANSLATES ACROSS THE
ONTARIO PENINSULA THIS AFTERNOON.

AS OF 07Z, WIDESPREAD LIGHT SHOWERS WITH EMBEDDED MODERATE BANDING
ARE OBSERVED OVER WESTERN LOWER. THIS AREA OF RAIN IS ASSOCIATED
WITH INCREASING ISENTROPIC ASCENT IMMEDIATELY IN ADVANCE OF THE
DIGGING SHORTWAVE. THERE WILL BE PLENTY OF CONTINUED DYNAMIC SUPPORT
TO MAINTAIN THIS ACTIVITY AS THE PRE-FRONTAL CORRIDOR OF WARM
ADVECTION SHIFTS ACROSS SOUTHEAST MICHIGAN THIS MORNING.

A SECONDARY FOCUS OF PRECIPITATION WILL TAKE SHAPE OVER THE AREA
LATE THIS MORNING THROUGH ABOUT 22Z. THIS ACTIVITY WILL MAINLY BE
DRIVEN BY SFC-500MB LAYER FGEN ASSOCIATED WITH THE SYSTEM COLD
FRONT. UPSTREAM ACTIVITY OVER WISCONSIN AND THE UPPER PENINSULA IS
ALREADY EVIDENT THIS MORNING, BUT WITH MODEL PROGS INDICATING A
NOTEWORTHY TIGHTENING OF THE BAROCLINIC ZONE ALONG WITH ADDED
DAYTIME INSTABILITY, A SOLID INCREASE IN COVERAGE AND INTENSITY IS
EXPECTED, ESPECIALLY FOR FLINT AND POINTS SOUTHEAST, INCLUDING METRO
DETROIT.

IN ADDITION, A MODERATE WIND FIELD WILL BE IN PLACE AROUND THE
WEAKENING SURFACE LOW WHICH SHOULD SUPPORT WIDESPREAD SUSTAINED
WINDS OF 15 TO 20 KNOTS. DIURNAL INSTABILITY WILL SUPPORT GUSTS
INCREASING TO 25 KNOTS. AN ADDED COMPONENT OF SYSTEM RELATIVE
ISENTROPIC DESCENT ASSOCIATED WITH FROPA CENTERED WITHIN A COUPLE
HOURS EITHER SIDE OF 21Z WILL SUPPORT AN ENHANCED POP OF WIND THAT
MAY TOP OUT AS HIGH AS 35 KNOTS. THIS BAND OF ENHANCED GUSTINESS
WILL WORK SOUTHEAST FROM THE SAGINAW VALLEY AROUND 19Z TO DETROIT
METRO AROUND 23Z. IN GENERAL, HOWEVER, MARGINAL BOUNDARY LAYER
GROWTH, ONGOING PRECIP, UNIMPRESSIVE DYNAMIC SUPPORT, AND A
MARGINAL-AT-BEST SYSTEM RELATIVE SETUP PRECLUDE WIND ADVISORY
CONCERNS AT THIS TIME. THE EXCEPTION IS HURON COUNTY WHERE WINDS
COMING OFF OF LAKE HURON WILL SUPPORT GUSTS APPROACHING 40 KNOTS
ALONG THE SHORELINE. SIMILAR CONDITIONS ARE NOT OUT OF THE
QUESTION ALONG THE SOUTHERN/EASTERN SHORES OF INNER SAGINAW BAY,
BUT POTENTIAL REMAINS TOO MARGINAL TO WARRANT A SOUTHWESTWARD
EXTENSION OF THE WIND ADVISORY ATTM.

IN THE WAKE OF THE COLD FRONT, 0-1KM THETA-E LAPSE RATES OVER LAKE
HURON WILL FALL TO AROUND -6C, MODERATE VALUES, BUT IMPRESSIVE FOR
THIS TIME OF YEAR. THE THERMODYNAMIC ENVIRONMENT WILL BE SIMILAR TO
THAT OVER LAKE SUPERIOR EARLY THIS MORNING AND SHOULD YIELD AN
EQUALLY HEALTHY LAKE RESPONSE. AS A RESULT, CATEGORICAL POPS REMAIN
IN PLACE FOR THE APPROPRIATE AREAS THROUGH MOST OF THE NIGHT. AS
COLD AIR MAKES INROADS INTO THE AREA DURING THE AFTERNOON, AND
PARTICULARLY TOWARD SUNSET, A CHANGEOVER TO SNOW IS LIKELY,
ESPECIALLY THOSE AREAS WHERE BOUNDARY LAYER WET BULB TEMPERATURES
ARE FORECAST TO FALL BELOW 0C. WHILE ALL AREAS WILL BE SUBJECT TO AT
LEAST A FEW FLAKES OVERNIGHT, LOCATIONS DOWNSTREAM OF LAKE HURON MAY
SEE A FEW TENTHS OF ACCUMULATION IN SPITE OF THE ANTECEDENT WET
SURFACE. WARM ADVECTION OFF THE LAKE REMAINS A CONCERN, PARTICULARLY
OVER FAR EASTERN AREAS, WHERE LOWS MAY STRUGGLE TO FALL BELOW 35-37F
AND PTYPE WILL STRUGGLE TO CHANGE OVER. CONVERSELY, LOCATIONS WEST
OF US-23 WILL REMAIN REMOVED FROM THE LAKE PLUME AND THE COMBINATION
OF UPPER 20S LOWS AND A STOUT WIND FIELD WILL PRODUCE WIND CHILLS IN
THE UPPER TEENS BY SATURDAY MORNING.

&&

.LONG TERM...SATURDAY THROUGH THURSDAY

THE CORE OF COLDEST LOW LEVEL AIR /850MB TEMPS OF -7 TO -10C/ WILL
ROTATE ACROSS LOWER MI DURING THE DAY SATURDAY. LAKE EFFECT
PRECIPITATION IS EXPECTED TO BE ONGOING ACROSS THE SOUTHERN HALF OF
LAKE HURON SAT MORNING UNDER NORTHERLY FLOW. MODEL SOUNDINGS SUGGEST
LAKE INDUCED EQUILIBRIUM LEVELS EXCEEDING 1500 FT. EVEN WITH SOME
HEAT FLUX OFF THE LAKE...THE DEGREE OF COLD AIR /1000-850MB
THICKNESSES DROPPING BELOW 1290M/ SUGGESTS PRECIP WILL BE MAINLY IN
THE FORM OF SNOW. THERE IS SOME CONCERN THAT IF THE DEEP LAYER
SYNOPTIC MOISTURE IS A LITTLE SLOWER TO DEPART...THERE COULD BE SOME
ACCUMULATIONS ACROSS THE EASTERN THUMB. THIS WILL BE SOMETHING FOR
LATER SHIFTS TO MONITOR. LIGHTER INTENSITY SNOW SHOWERS AND/OR
FLURRIES ARE CERTAINLY POSSIBLE FARTHER INLAND. AN AGGRESSIVE PUSH OF
DRY AIR...BACKING LOW LEVEL FLOW AND LOWER INVERSION BASES DUE TO
STRENGTHENING LARGE SCALE SUBSIDENCE WILL NOT ONLY END THE LAKE
EFFECT BUT WILL SUPPORT A CLEARING TREND FROM WEST TO EAST DURING
THE AFTERNOON AND EVENING. SAT HIGHS WILL LIKELY FALL SHORT OF 40
DEGREES OVER MUCH OF THE AREA GIVEN THE DEGREE OF COLD AIR. ENOUGH
DECOUPLING IN THE BOUNDARY LAYER WITH SFC HIGH PRESSURE BUILDING IN
FROM THE WEST SAT NIGHT WILL DROP LOWS WELL DOWN INTO THE 20S.

ALTHOUGH AMPLIFIED...THE LARGE SCALE PATTERN WILL REMAIN PROGRESSIVE
WITH MID LEVEL RIDING EXPANDING ACROSS THE GREAT LAKES BY THE END OF
THE WEEKEND. THIS AND THE DEPARTURE OF THE SFC HIGH TO THE EAST WILL
ESTABLISH A WARM AIR ADVECTION REGIME ACROSS LOWER MI...LEADING TO A
MODEST WARMING TREND HEADING INTO EARLY NEXT WEEK. MOIST ADVECTION
WILL THEN INCREASE MON NIGHT INTO TUES IN ADVANCE OF A LONG WAVE
TROUGH...SUPPORTING THE NEXT CHANCE FOR PRECIP /WARM ENOUGH FOR ALL
RAIN WITH THIS SYSTEM/. THE MEDIUM RANGE MODEL SUITE SUGGEST THE
NORTHERN STREAM WILL REMAIN PROGRESSIVE THROUGH NEXT WEEK...WITH THE
NEXT MID LEVEL WAVE AND SHOT AT SOME COLDER AIR ARRIVING LATE IN THE
FORECAST PERIOD.

&&

.MARINE...GALE WARNINGS REMAIN IN EFFECT FOR ALL MARINE AREAS TODAY
INTO TONIGHT. A PUSH OF ARCTIC AIR WILL CONTINUE TO FUNNEL INTO THE
REGION BEHIND A COLD FRONT ASSOCIATED WITH A LOW PRESSURE SYSTEM
FORECAST TO MOVE FROM NORTHERN LAKE HURON THIS MORNING INTO THE
UPPER OHIO VALLEY BY EVENING. HIGH PRESSURE NUDGING INTO THE WESTERN
GREAT LAKES FROM THE PLAINS WILL SUSTAIN A TIGHT PRESSURE GRADIENT
ALONG THE BACK SIDE OF THE DEPARTING LOW. THIS COMBINED WITH THE
HIGHLY UNSTABLE CONDITIONS OVER THE MARINE AREAS WILL SUPPORT GALE
FORCE WINDS DEVELOPING OVER NORTHERN LAKE HURON THIS MORNING AND THE
SOUTHERN HALF OF THE LAKE BY AFTERNOON. WINDS AND WAVES WILL SLOWLY
DECREASE SATURDAY INTO SATURDAY NIGHT AS HIGH PRESSURE BUILDS IN
FROM THE WEST.

&&

.AVIATION...ISSUED 1205 AM EDT FRI OCT 31 2014

//DISCUSSION...

AN ACTIVE PERIOD OF AVIATION WEATHER IS IN STORE TODAY THROUGH
FRIDAY NIGHT AS A STRONG LOW PRESSURE SYSTEM AND COLD FRONT MOVE
THROUGH THE GREAT LAKES. THE GREATEST IMPACT WILL BE IFR AND 30+
KNOT NORTH WIND ALONG AND BEHIND THE FRONT ACCOMPANIED BY RAIN AND
POSSIBLY A MIX OF RAIN AND SNOW TOWARD SUNSET. THE FIRST CHANCE OF
RAIN WILL ARRIVE WITH THE LEADING SURFACE TROUGH/FRONT AROUND
SUNRISE. THIS WILL BE FOLLOWED BY A DRY SLOT THAT WILL LEAD TO
BREAKS IN THE RAIN PATTERN FROM MID MORNING THROUGH EARLY AFTERNOON
BUT MVFR CEILING AND PERHAPS SOME FOG RESTRICTION WILL PERSIST
BETWEEN THE SURFACE TROUGH AND PRIMARY COLD FRONT. THE PASSAGE OF
THE FRONT WILL BRING IFR IN THE FORM OF LOW CEILING AND HEAVIER RAIN
THAT WILL PERSIST INTO FRIDAY EVENING POSSIBLY MIXING WITH SNOW LATE
IN THE DAY.

FOR DTW... TURNING POINTS IN THE FORECAST WILL BE WITH THE
PREFRONTAL TROUGH/FRONT SHORTLY AFTER SUNRISE WHICH WILL BRING MVFR
CEILING...SOME LIGHT RAIN SHOWERS...AND PERHAPS SOME FOG. THIS WILL
BE FOLLOWED BY THE COLD FRONT BY MID AFTERNOON WHICH WILL BRING A
SHARP TURN IN THE WINDS FROM THE NORTH LIKELY GUSTING TO 30 KNOTS OR
GREATER...IFR CEILING...AND HEAVIER RAIN. A MIX OF RAIN AND SNOW IS
POSSIBLE LATE IN THE DAY BUT THE MIX WILL LIKELY PREVENT
ACCUMULATION ON THE RELATIVELY WARM GROUND SURFACES.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE IN CEILING BELOW 5000 FEET DURING THE NIGHT...
  HIGH CONFIDENCE DURING THE DAY AND FRIDAY NIGHT.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN LATE TOWARD EVENING AND
  FRIDAY NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 10 PM EDT THIS EVENING
     FOR MIZ049.

LAKE HURON...GALE WARNING FROM 11 AM THIS MORNING TO NOON EDT SATURDAY FOR
     LHZ363-441-462.

     GALE WARNING FROM 2 PM THIS AFTERNOON TO NOON EDT SATURDAY FOR
     LHZ442-443-463-464.

     GALE WARNING FROM 8 AM THIS MORNING TO 8 PM EDT THIS EVENING FOR
     LHZ361.

     GALE WARNING FROM 8 AM THIS MORNING TO 2 AM EDT SATURDAY FOR LHZ362.

     GALE WARNING FROM 11 AM THIS MORNING TO 5 AM EDT SATURDAY FOR
     LHZ421-422.

LAKE ST CLAIR...GALE WARNING FROM 6 PM THIS EVENING TO 10 AM EDT SATURDAY FOR
     LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING FROM 6 PM THIS EVENING TO 10 AM EDT SATURDAY FOR
     LEZ444.

&&

$$

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


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





000
FXUS63 KDTX 310405
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1205 AM EDT FRI OCT 31 2014

.AVIATION...

//DISCUSSION...

AN ACTIVE PERIOD OF AVIATION WEATHER IS IN STORE TODAY THROUGH
FRIDAY NIGHT AS A STRONG LOW PRESSURE SYSTEM AND COLD FRONT MOVE
THROUGH THE GREAT LAKES. THE GREATEST IMPACT WILL BE IFR AND 30+
KNOT NORTH WIND ALONG AND BEHIND THE FRONT ACCOMPANIED BY RAIN AND
POSSIBLY A MIX OF RAIN AND SNOW TOWARD SUNSET. THE FIRST CHANCE OF
RAIN WILL ARRIVE WITH THE LEADING SURFACE TROUGH/FRONT AROUND
SUNRISE. THIS WILL BE FOLLOWED BY A DRY SLOT THAT WILL LEAD TO
BREAKS IN THE RAIN PATTERN FROM MID MORNING THROUGH EARLY AFTERNOON
BUT MVFR CEILING AND PERHAPS SOME FOG RESTRICTION WILL PERSIST
BETWEEN THE SURFACE TROUGH AND PRIMARY COLD FRONT. THE PASSAGE OF
THE FRONT WILL BRING IFR IN THE FORM OF LOW CEILING AND HEAVIER RAIN
THAT WILL PERSIST INTO FRIDAY EVENING POSSIBLY MIXING WITH SNOW LATE
IN THE DAY.

FOR DTW... TURNING POINTS IN THE FORECAST WILL BE WITH THE
PREFRONTAL TROUGH/FRONT SHORTLY AFTER SUNRISE WHICH WILL BRING MVFR
CEILING...SOME LIGHT RAIN SHOWERS...AND PERHAPS SOME FOG. THIS WILL
BE FOLLOWED BY THE COLD FRONT BY MID AFTERNOON WHICH WILL BRING A
SHARP TURN IN THE WINDS FROM THE NORTH LIKELY GUSTING TO 30 KNOTS OR
GREATER...IFR CEILING...AND HEAVIER RAIN. A MIX OF RAIN AND SNOW IS
POSSIBLE LATE IN THE DAY BUT THE MIX WILL LIKELY PREVENT
ACCUMULATION ON THE RELATIVELY WARM GROUND SURFACES.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE IN CEILING BELOW 5000 FEET DURING THE NIGHT...
  HIGH CONFIDENCE DURING THE DAY AND FRIDAY NIGHT.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN LATE TOWARD EVENING AND
  FRIDAY NIGHT.

&&

.PREV DISCUSSION...ISSUED 920 PM EDT THU OCT 30 2014

UPDATE...

LOW PRESSURE IS DEVELOPING ON SCHEDULE OVER THE NORTHERN GREAT
LAKES TONIGHT WHICH WILL BRING AN ACTIVE PERIOD OF WEATHER TO SE
MICHIGAN IN THE FORM OF INCREASING SHOWER COVERAGE LATER TONIGHT
AND THEN WIDESPREAD SHOWERS AND STRONG WIND FRIDAY. NORTH WIND IS
EXPECTED TO DEVELOP DURING FRIDAY AFTERNOON WITH GUSTS OF 30 TO 40
MPH LIKELY TO COMBINE WITH RAIN SHOWERS AND POSSIBLY A MIX OF SNOW
FOR HARSH WEATHER TOWARD SUNSET. GUSTS NEAR 45 MPH WIND ADVISORY
LEVELS HAVE GREATER POTENTIAL TOWARD FRIDAY EVENING WHEN THE BEST
ISENTROPIC DESCENT AND MID LEVEL SUBSIDENCE IS INDICATED IN MODEL
DATA AS THE LOW EXITS THE REGION. TIMING ON ANY ISSUANCE OF
HEADLINES REMAINS BEST SUITED FOR THE OVERNIGHT FORECAST PACKAGE.

UNTIL THEN...EVENING SURFACE ANALYSIS INDICATES LOW PRESSURE
ORGANIZING OVER THE STRAITS REGION WITH THE FIRST COLD FRONT OR
PREFRONTAL TROUGH EXTENDING THROUGH SOUTHERN WISCONSIN. THIS
PLACES WEAK SOUTHWEST FLOW AHEAD OF THESE FEATURES OVER LOWER
MICHIGAN THAT WILL BRING IN MILD AIR FOR THE BULK OF THE NIGHT AND
MAINTAIN TEMPS MOSTLY IN THE LOWER 40S. PLENTIFUL CLOUD COVER AND
POCKETS OF LIGHT RAIN ARE BEING FORCED BY GENTLE ISENTROPIC LIFT
AS THE LOW AND MID LEVEL THETA-E RIDGE FORMS AHEAD OF THE FRONT.
THE LATEST MODEL OUTPUT SHOWS THE THETA-E RIDGE BECOMING WELL
DEFINED DURING THE NIGHT REPRESENTING A SURGE OF LOW LEVEL
MOISTURE THAT WILL INTERACT WITH THE FIRST FRONTAL PASSAGE AND
DYNAMIC SUPPORT FROM THE UPPER LEVEL CIRCULATION. AN UPTICK IN
BOTH COVERAGE AND INTENSITY OF RAIN IS THEN EXPECTED ALONG THE
FRONT AS IT PASSES THROUGH SE MICHIGAN...FIRST IN THE TRI CITIES
AFTER MIDNIGHT AND THROUGH THE DETROIT AREA TOWARD SUNRISE
LASTING THROUGH ABOUT MID FRIDAY MORNING. THE GOING FORECAST LOOKS
SOLID RAMPING UP TO CATEGORICAL POPS DURING THIS TIME.

PREV DISCUSSION...ISSUED 422 PM EDT THU OCT 30 2014

SHORT TERM...THROUGH TONIGHT

UPPER LEVEL FEATURE OF NOTE IS A VIGOROUS...TIGHT PV ANOMALY
DROPPING SOUTHWARD INTO FAR NORTHERN MN AT 17Z. 12Z SUITE IN GOOD
AGREEMENT WITH THE PROGRESSION OF THIS FEATURE IN THE SHORT
TERM...PLACING IT NEAR THE WI/IL BORDER BY 12Z FRIDAY. CURRENTLY
OVER THE LOCAL AREA...SHORTWAVE RIDGING HAS PUSHED EAST OF THE
REGION...AND THE PATTERN WILL BE CHARACTERIZED BY GRADUAL HEIGHT
FALLS/WEAK WAA AS THE UPPER FEATURE NEARS. THIS WILL SUSTAIN THE
MIDLEVEL CLOUD DECK AND MAY ALLOW FOR SOME SPRINKLES/LIGHT SHOWERS
TO EXPAND SOUTHWARD WITH TIME INTO OUR REGION THROUGH THE EARLY PART
OF THE OVERNIGHT HOURS. ASCENT INCREASES FURTHER TOWARD THE END OF
THE PERIOD AS THE UPPER LEVEL FEATURE NEARS. SURFACE LOW WILL BE
ROUGHLY OVER SAGINAW BAY BY 12Z FRIDAY WITH A COLD FRONT EXTENDING
SWWD. THE HEAVIER BANDED PRECIP ASSOCIATED WITH FGEN CIRCULATION
SHOULD STILL MOSTLY BE TO OUR NORTHWEST IN THE COLDER POST-FRONTAL
AIR AT THAT POINT...BUT ASCENT SHOULD BE ENOUGH TO WARRANT
CATEGORICAL/LIKELY POPS AFTER 09Z OVER THE SAGINAW VALLEY/FLINT
REGIONS...RESPECTIVELY. LOWS WILL NOT DROP TOO MUCH TONIGHT WITH THE
INSULATING CLOUD DECK...EXPECTING MAINLY LOW 40S.

LONG TERM...FRIDAY THROUGH NEXT THURSDAY

UPPER WAVE OVER WESTERN ONTARIO WILL DIVE THROUGH THE WESTERN GREAT
LAKES AND THEN TOWARDS THE TENNESSEE VALLEY BY FRIDAY EVENING IN
RESPONSE TO AN AMPLIFICATION OF THE UPPER PATTERN OVER NORTH
AMERICA...WHICH WILL RESULT IN STRONG RIDGING EXTENDING UP THROUGH
CENTRAL CANADA. AS THE WAVE DROPS SOUTH...LOW PRESSURE NOW NORTH OF
LAKE SUPERIOR WILL DEEPEN AS IT TRACKS THROUGH LAKE HURON FRIDAY
MORNING AND INTO LAKE ERIE FRIDAY EVENING. THE PASSAGE OF THIS
SYSTEM THROUGH THE AREA WILL PULL AN ARCTIC COLD FRONT DOWN THROUGH
THE AREA. THE FRONT IS CURRENTLY DROPPING THROUGH NORTHERN
MINNESOTA...WHERE SURFACE OBSERVATIONS HAVE BEEN SHOWING GUSTY
WINDS...FALLING TEMPERATURES AND A CHANGE OVER IN PRECIPITATION TYPE
FROM RAIN TO SNOW.

PRECIPITATION SHOULD BE WORKING DOWN INTO THE AREA AT THE START OF
THE DAY TOMORROW AS THE FRONT APPROACHES. EXPECTING BEST COVERAGE
AND PRECIP RATES AS DEFORMATION AXIS AND EVEN A WEAK TROWAL ON THE
NORTH SIDE OF THE SYSTEM DROPS ACROSS SOUTHEAST MICHIGAN FROM EARLY
AFTERNOON THROUGH EVENING. DEFORMATION AXIS IS EXPECTED TO LINGER A
BIT LONGER OVER THE FAR EASTERN PORTION OF MICHIGAN FRIDAY NIGHT AS
THE LOW TAKES ON MORE OF A SOUTHERLY TRAJECTORY ACROSS LAKE ERIE.
ARCTIC FRONTAL BOUNDARY WILL ALSO DROP ACROSS THE AREA...WITH TIMING
CURRENTLY EXPECTED FROM VERY LATE MORNING THROUGH EARLY EVENING.
MODEL FORECAST SOUNDINGS CONTINUE TO SUPPORT A CHANGEOVER IN
PRECIPITATION TYPE FROM RAIN TO SNOW AS COLDER AIR WORKS IN BEHIND
THE FRONT. ACCUMULATIONS IF ANY LOOK LIGHT AT THIS TIME...AND
CONFINED MAINLY TO GRASSY AND ELEVATED SURFACES. WILL HAVE TO WATCH
LAKE EFFECT POTENTIAL FROM OFF LAKE HURON BEHIND THE FRONT WITH
STEEP LAPSE RATES DEVELOPING OVER THE WARMER LAKE WATERS AND STRONG
NORTHERLY FLOW. LAKE-MODIFIED AIRMASS ALSO MAKES PRECIP TYPE A
LITTLE MORE CHALLENGING...AS IT COULD KEEP PRECIP RAIN OR A MIX OF
RAIN/SNOW OVER THE EASTERN HALF OF THE AREA.

OTHER CONCERN TOMORROW WILL BE THE STRONG CORE OF 50 KT WINDS AT 925-
850MB WORKING DOWN ON THE BACKSIDE OF THE SYSTEM FROM LATE AFTERNOON
INTO THE OVERNIGHT. FORECAST SOUNDINGS FROM BOTH THE NAM AND GFS
SHOW THE BOUNDARY LAYER SHOULD BE SUFFICIENTLY DEEP ENOUGH BEHIND
THE FRONT FOR GUSTS TO 45 OR PERHAPS EVEN 50 MPH TO WORK DOWN TO THE
SURFACE AS LAPSE RATES ALSO STEEPEN. MODELS HAVE WAVERED A BIT ON
THIS OVER THE PAST FEW RUNS...AND DO NOT SHOW STRONG DESCENT LIKE WE
HAVE HAD WITH WIND EVENTS IN THE PAST. WILL WATCH FOR ANOTHER ROUND
OF MODEL RUNS...BUT A WIND ADVISORY MAY BE REQUIRED.

DRIER AIR LOOKS TO ARRIVE SATURDAY AFTERNOON AS RIDGING BUILDS INTO
THE GREAT LAKES AHEAD OF THE AMPLIFIED RIDGE AXIS OVER THE PLAINS.
THE DRIER AIR AND LOWERING INVERSION HEIGHTS SHOULD PUT AN END TO
LAKE EFFECT FROM OFF LAKE HURON BY AFTERNOON. POST-FRONTAL
TEMPERATURES WILL BE QUITE COLD...WITH HIGHS ONLY IN THE UPPER 30S
AND LOW 40S. CLEAR SKIES AND LIGHT WINDS SATURDAY NIGHT WILL SET US
UP FOR THE COLDEST NIGHT OF THE SEASON SO FAR...WITH LOWS SOLIDLY IN
THE 20S.

AS SURFACE HIGH PRESSURE SHIFTS TOWARDS THE EAST ON SUNDAY...FLOW
TURNS SOUTHERLY AND SOUTHEAST MICHIGAN RECOVERS FROM THE FRIGID
CONDITIONS FROM THE PREVIOUS TWO DAYS. HIGHS WILL REACH THE MID 50S
BY TUESDAY. A SOUTHWEST JET WILL THEN USHER IN PACIFIC MOISTURE TO
COMBINE WITH A FRONTAL SYSTEM TUESDAY INTO EARLY WEDNESDAY. LOCATION
AND FORWARD SPEED OF THE FRONT IS UP FOR DEBATE...SO THERE COULD A
LARGE TEMP SWING/ERROR ON DAYS 6-7.

MARINE...LOW PRESSURE WILL DEEPEN AS IT TRACKS FROM LAKE SUPERIOR
TO SOUTH OF LAKE ERIE BY FRIDAY EVENING. AS THE SYSTEM DROPS THROUGH
THE CENTRAL GREAT LAKES...IT WILL PULL AN ARCTIC COLD FRONT DOWN
ACROSS THE REGION. THE COLD AIR WILL FILL IN OVER THE WARMER LAKE
WATERS...ALLOWING A STRONG CORE OF WINDS ALOFT TO MIX DOWN TO THE
LAKE SURFACE. GALE FORCE WIND GUSTS ARE EXPECTED TO DEVELOP OVER
LAKE HURON ON FRIDAY...AND SPREAD TO LAKE ST CLAIR AND WESTERN LAKE
ERIE BY FRIDAY NIGHT. THE STRONG AND PERSISTENT NORTHERLY WINDS WILL
ALLOW WAVE HEIGHTS TO BUILD AS HIGH AS 15 FEET OVER THE SOUTHERN
PORTION OF LAKE HURON BY FRIDAY EVENING. WINDS WILL GRADUALLY
DIMINISH ON SATURDAY AS A RIDGE OF HIGH PRESSURE SLIDES INTO THE
AREA. LARGE WAVES OVER SOUTHERN LAKE HURON WILL BE SLOW TO SUBSIDE
HOWEVER...NOT DROPPING BELOW 4 FEET UNTIL SATURDAY EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...GALE WARNING FROM 11 AM THIS MORNING TO 8 AM EDT SATURDAY FOR
     LHZ363-421-422-441-462.

     GALE WARNING FROM 2 PM THIS AFTERNOON TO 10 AM EDT SATURDAY FOR
     LHZ442-443-463-464.

     GALE WARNING FROM 8 AM THIS MORNING TO 8 PM EDT THIS EVENING FOR
     LHZ361.

     GALE WARNING FROM 8 AM THIS MORNING TO 2 AM EDT SATURDAY FOR LHZ362.

LAKE ST CLAIR...GALE WARNING FROM 8 PM THIS EVENING TO 10 AM EDT SATURDAY FOR
     LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING FROM 8 PM THIS EVENING TO 10 AM EDT SATURDAY FOR
     LEZ444.

&&

$$

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


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





000
FXUS63 KDTX 310405
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1205 AM EDT FRI OCT 31 2014

.AVIATION...

//DISCUSSION...

AN ACTIVE PERIOD OF AVIATION WEATHER IS IN STORE TODAY THROUGH
FRIDAY NIGHT AS A STRONG LOW PRESSURE SYSTEM AND COLD FRONT MOVE
THROUGH THE GREAT LAKES. THE GREATEST IMPACT WILL BE IFR AND 30+
KNOT NORTH WIND ALONG AND BEHIND THE FRONT ACCOMPANIED BY RAIN AND
POSSIBLY A MIX OF RAIN AND SNOW TOWARD SUNSET. THE FIRST CHANCE OF
RAIN WILL ARRIVE WITH THE LEADING SURFACE TROUGH/FRONT AROUND
SUNRISE. THIS WILL BE FOLLOWED BY A DRY SLOT THAT WILL LEAD TO
BREAKS IN THE RAIN PATTERN FROM MID MORNING THROUGH EARLY AFTERNOON
BUT MVFR CEILING AND PERHAPS SOME FOG RESTRICTION WILL PERSIST
BETWEEN THE SURFACE TROUGH AND PRIMARY COLD FRONT. THE PASSAGE OF
THE FRONT WILL BRING IFR IN THE FORM OF LOW CEILING AND HEAVIER RAIN
THAT WILL PERSIST INTO FRIDAY EVENING POSSIBLY MIXING WITH SNOW LATE
IN THE DAY.

FOR DTW... TURNING POINTS IN THE FORECAST WILL BE WITH THE
PREFRONTAL TROUGH/FRONT SHORTLY AFTER SUNRISE WHICH WILL BRING MVFR
CEILING...SOME LIGHT RAIN SHOWERS...AND PERHAPS SOME FOG. THIS WILL
BE FOLLOWED BY THE COLD FRONT BY MID AFTERNOON WHICH WILL BRING A
SHARP TURN IN THE WINDS FROM THE NORTH LIKELY GUSTING TO 30 KNOTS OR
GREATER...IFR CEILING...AND HEAVIER RAIN. A MIX OF RAIN AND SNOW IS
POSSIBLE LATE IN THE DAY BUT THE MIX WILL LIKELY PREVENT
ACCUMULATION ON THE RELATIVELY WARM GROUND SURFACES.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE IN CEILING BELOW 5000 FEET DURING THE NIGHT...
  HIGH CONFIDENCE DURING THE DAY AND FRIDAY NIGHT.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN LATE TOWARD EVENING AND
  FRIDAY NIGHT.

&&

.PREV DISCUSSION...ISSUED 920 PM EDT THU OCT 30 2014

UPDATE...

LOW PRESSURE IS DEVELOPING ON SCHEDULE OVER THE NORTHERN GREAT
LAKES TONIGHT WHICH WILL BRING AN ACTIVE PERIOD OF WEATHER TO SE
MICHIGAN IN THE FORM OF INCREASING SHOWER COVERAGE LATER TONIGHT
AND THEN WIDESPREAD SHOWERS AND STRONG WIND FRIDAY. NORTH WIND IS
EXPECTED TO DEVELOP DURING FRIDAY AFTERNOON WITH GUSTS OF 30 TO 40
MPH LIKELY TO COMBINE WITH RAIN SHOWERS AND POSSIBLY A MIX OF SNOW
FOR HARSH WEATHER TOWARD SUNSET. GUSTS NEAR 45 MPH WIND ADVISORY
LEVELS HAVE GREATER POTENTIAL TOWARD FRIDAY EVENING WHEN THE BEST
ISENTROPIC DESCENT AND MID LEVEL SUBSIDENCE IS INDICATED IN MODEL
DATA AS THE LOW EXITS THE REGION. TIMING ON ANY ISSUANCE OF
HEADLINES REMAINS BEST SUITED FOR THE OVERNIGHT FORECAST PACKAGE.

UNTIL THEN...EVENING SURFACE ANALYSIS INDICATES LOW PRESSURE
ORGANIZING OVER THE STRAITS REGION WITH THE FIRST COLD FRONT OR
PREFRONTAL TROUGH EXTENDING THROUGH SOUTHERN WISCONSIN. THIS
PLACES WEAK SOUTHWEST FLOW AHEAD OF THESE FEATURES OVER LOWER
MICHIGAN THAT WILL BRING IN MILD AIR FOR THE BULK OF THE NIGHT AND
MAINTAIN TEMPS MOSTLY IN THE LOWER 40S. PLENTIFUL CLOUD COVER AND
POCKETS OF LIGHT RAIN ARE BEING FORCED BY GENTLE ISENTROPIC LIFT
AS THE LOW AND MID LEVEL THETA-E RIDGE FORMS AHEAD OF THE FRONT.
THE LATEST MODEL OUTPUT SHOWS THE THETA-E RIDGE BECOMING WELL
DEFINED DURING THE NIGHT REPRESENTING A SURGE OF LOW LEVEL
MOISTURE THAT WILL INTERACT WITH THE FIRST FRONTAL PASSAGE AND
DYNAMIC SUPPORT FROM THE UPPER LEVEL CIRCULATION. AN UPTICK IN
BOTH COVERAGE AND INTENSITY OF RAIN IS THEN EXPECTED ALONG THE
FRONT AS IT PASSES THROUGH SE MICHIGAN...FIRST IN THE TRI CITIES
AFTER MIDNIGHT AND THROUGH THE DETROIT AREA TOWARD SUNRISE
LASTING THROUGH ABOUT MID FRIDAY MORNING. THE GOING FORECAST LOOKS
SOLID RAMPING UP TO CATEGORICAL POPS DURING THIS TIME.

PREV DISCUSSION...ISSUED 422 PM EDT THU OCT 30 2014

SHORT TERM...THROUGH TONIGHT

UPPER LEVEL FEATURE OF NOTE IS A VIGOROUS...TIGHT PV ANOMALY
DROPPING SOUTHWARD INTO FAR NORTHERN MN AT 17Z. 12Z SUITE IN GOOD
AGREEMENT WITH THE PROGRESSION OF THIS FEATURE IN THE SHORT
TERM...PLACING IT NEAR THE WI/IL BORDER BY 12Z FRIDAY. CURRENTLY
OVER THE LOCAL AREA...SHORTWAVE RIDGING HAS PUSHED EAST OF THE
REGION...AND THE PATTERN WILL BE CHARACTERIZED BY GRADUAL HEIGHT
FALLS/WEAK WAA AS THE UPPER FEATURE NEARS. THIS WILL SUSTAIN THE
MIDLEVEL CLOUD DECK AND MAY ALLOW FOR SOME SPRINKLES/LIGHT SHOWERS
TO EXPAND SOUTHWARD WITH TIME INTO OUR REGION THROUGH THE EARLY PART
OF THE OVERNIGHT HOURS. ASCENT INCREASES FURTHER TOWARD THE END OF
THE PERIOD AS THE UPPER LEVEL FEATURE NEARS. SURFACE LOW WILL BE
ROUGHLY OVER SAGINAW BAY BY 12Z FRIDAY WITH A COLD FRONT EXTENDING
SWWD. THE HEAVIER BANDED PRECIP ASSOCIATED WITH FGEN CIRCULATION
SHOULD STILL MOSTLY BE TO OUR NORTHWEST IN THE COLDER POST-FRONTAL
AIR AT THAT POINT...BUT ASCENT SHOULD BE ENOUGH TO WARRANT
CATEGORICAL/LIKELY POPS AFTER 09Z OVER THE SAGINAW VALLEY/FLINT
REGIONS...RESPECTIVELY. LOWS WILL NOT DROP TOO MUCH TONIGHT WITH THE
INSULATING CLOUD DECK...EXPECTING MAINLY LOW 40S.

LONG TERM...FRIDAY THROUGH NEXT THURSDAY

UPPER WAVE OVER WESTERN ONTARIO WILL DIVE THROUGH THE WESTERN GREAT
LAKES AND THEN TOWARDS THE TENNESSEE VALLEY BY FRIDAY EVENING IN
RESPONSE TO AN AMPLIFICATION OF THE UPPER PATTERN OVER NORTH
AMERICA...WHICH WILL RESULT IN STRONG RIDGING EXTENDING UP THROUGH
CENTRAL CANADA. AS THE WAVE DROPS SOUTH...LOW PRESSURE NOW NORTH OF
LAKE SUPERIOR WILL DEEPEN AS IT TRACKS THROUGH LAKE HURON FRIDAY
MORNING AND INTO LAKE ERIE FRIDAY EVENING. THE PASSAGE OF THIS
SYSTEM THROUGH THE AREA WILL PULL AN ARCTIC COLD FRONT DOWN THROUGH
THE AREA. THE FRONT IS CURRENTLY DROPPING THROUGH NORTHERN
MINNESOTA...WHERE SURFACE OBSERVATIONS HAVE BEEN SHOWING GUSTY
WINDS...FALLING TEMPERATURES AND A CHANGE OVER IN PRECIPITATION TYPE
FROM RAIN TO SNOW.

PRECIPITATION SHOULD BE WORKING DOWN INTO THE AREA AT THE START OF
THE DAY TOMORROW AS THE FRONT APPROACHES. EXPECTING BEST COVERAGE
AND PRECIP RATES AS DEFORMATION AXIS AND EVEN A WEAK TROWAL ON THE
NORTH SIDE OF THE SYSTEM DROPS ACROSS SOUTHEAST MICHIGAN FROM EARLY
AFTERNOON THROUGH EVENING. DEFORMATION AXIS IS EXPECTED TO LINGER A
BIT LONGER OVER THE FAR EASTERN PORTION OF MICHIGAN FRIDAY NIGHT AS
THE LOW TAKES ON MORE OF A SOUTHERLY TRAJECTORY ACROSS LAKE ERIE.
ARCTIC FRONTAL BOUNDARY WILL ALSO DROP ACROSS THE AREA...WITH TIMING
CURRENTLY EXPECTED FROM VERY LATE MORNING THROUGH EARLY EVENING.
MODEL FORECAST SOUNDINGS CONTINUE TO SUPPORT A CHANGEOVER IN
PRECIPITATION TYPE FROM RAIN TO SNOW AS COLDER AIR WORKS IN BEHIND
THE FRONT. ACCUMULATIONS IF ANY LOOK LIGHT AT THIS TIME...AND
CONFINED MAINLY TO GRASSY AND ELEVATED SURFACES. WILL HAVE TO WATCH
LAKE EFFECT POTENTIAL FROM OFF LAKE HURON BEHIND THE FRONT WITH
STEEP LAPSE RATES DEVELOPING OVER THE WARMER LAKE WATERS AND STRONG
NORTHERLY FLOW. LAKE-MODIFIED AIRMASS ALSO MAKES PRECIP TYPE A
LITTLE MORE CHALLENGING...AS IT COULD KEEP PRECIP RAIN OR A MIX OF
RAIN/SNOW OVER THE EASTERN HALF OF THE AREA.

OTHER CONCERN TOMORROW WILL BE THE STRONG CORE OF 50 KT WINDS AT 925-
850MB WORKING DOWN ON THE BACKSIDE OF THE SYSTEM FROM LATE AFTERNOON
INTO THE OVERNIGHT. FORECAST SOUNDINGS FROM BOTH THE NAM AND GFS
SHOW THE BOUNDARY LAYER SHOULD BE SUFFICIENTLY DEEP ENOUGH BEHIND
THE FRONT FOR GUSTS TO 45 OR PERHAPS EVEN 50 MPH TO WORK DOWN TO THE
SURFACE AS LAPSE RATES ALSO STEEPEN. MODELS HAVE WAVERED A BIT ON
THIS OVER THE PAST FEW RUNS...AND DO NOT SHOW STRONG DESCENT LIKE WE
HAVE HAD WITH WIND EVENTS IN THE PAST. WILL WATCH FOR ANOTHER ROUND
OF MODEL RUNS...BUT A WIND ADVISORY MAY BE REQUIRED.

DRIER AIR LOOKS TO ARRIVE SATURDAY AFTERNOON AS RIDGING BUILDS INTO
THE GREAT LAKES AHEAD OF THE AMPLIFIED RIDGE AXIS OVER THE PLAINS.
THE DRIER AIR AND LOWERING INVERSION HEIGHTS SHOULD PUT AN END TO
LAKE EFFECT FROM OFF LAKE HURON BY AFTERNOON. POST-FRONTAL
TEMPERATURES WILL BE QUITE COLD...WITH HIGHS ONLY IN THE UPPER 30S
AND LOW 40S. CLEAR SKIES AND LIGHT WINDS SATURDAY NIGHT WILL SET US
UP FOR THE COLDEST NIGHT OF THE SEASON SO FAR...WITH LOWS SOLIDLY IN
THE 20S.

AS SURFACE HIGH PRESSURE SHIFTS TOWARDS THE EAST ON SUNDAY...FLOW
TURNS SOUTHERLY AND SOUTHEAST MICHIGAN RECOVERS FROM THE FRIGID
CONDITIONS FROM THE PREVIOUS TWO DAYS. HIGHS WILL REACH THE MID 50S
BY TUESDAY. A SOUTHWEST JET WILL THEN USHER IN PACIFIC MOISTURE TO
COMBINE WITH A FRONTAL SYSTEM TUESDAY INTO EARLY WEDNESDAY. LOCATION
AND FORWARD SPEED OF THE FRONT IS UP FOR DEBATE...SO THERE COULD A
LARGE TEMP SWING/ERROR ON DAYS 6-7.

MARINE...LOW PRESSURE WILL DEEPEN AS IT TRACKS FROM LAKE SUPERIOR
TO SOUTH OF LAKE ERIE BY FRIDAY EVENING. AS THE SYSTEM DROPS THROUGH
THE CENTRAL GREAT LAKES...IT WILL PULL AN ARCTIC COLD FRONT DOWN
ACROSS THE REGION. THE COLD AIR WILL FILL IN OVER THE WARMER LAKE
WATERS...ALLOWING A STRONG CORE OF WINDS ALOFT TO MIX DOWN TO THE
LAKE SURFACE. GALE FORCE WIND GUSTS ARE EXPECTED TO DEVELOP OVER
LAKE HURON ON FRIDAY...AND SPREAD TO LAKE ST CLAIR AND WESTERN LAKE
ERIE BY FRIDAY NIGHT. THE STRONG AND PERSISTENT NORTHERLY WINDS WILL
ALLOW WAVE HEIGHTS TO BUILD AS HIGH AS 15 FEET OVER THE SOUTHERN
PORTION OF LAKE HURON BY FRIDAY EVENING. WINDS WILL GRADUALLY
DIMINISH ON SATURDAY AS A RIDGE OF HIGH PRESSURE SLIDES INTO THE
AREA. LARGE WAVES OVER SOUTHERN LAKE HURON WILL BE SLOW TO SUBSIDE
HOWEVER...NOT DROPPING BELOW 4 FEET UNTIL SATURDAY EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...GALE WARNING FROM 11 AM THIS MORNING TO 8 AM EDT SATURDAY FOR
     LHZ363-421-422-441-462.

     GALE WARNING FROM 2 PM THIS AFTERNOON TO 10 AM EDT SATURDAY FOR
     LHZ442-443-463-464.

     GALE WARNING FROM 8 AM THIS MORNING TO 8 PM EDT THIS EVENING FOR
     LHZ361.

     GALE WARNING FROM 8 AM THIS MORNING TO 2 AM EDT SATURDAY FOR LHZ362.

LAKE ST CLAIR...GALE WARNING FROM 8 PM THIS EVENING TO 10 AM EDT SATURDAY FOR
     LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING FROM 8 PM THIS EVENING TO 10 AM EDT SATURDAY FOR
     LEZ444.

&&

$$

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


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





000
FXUS63 KDTX 310120
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
920 PM EDT THU OCT 30 2014

.UPDATE...

LOW PRESSURE IS DEVELOPING ON SCHEDULE OVER THE NORTHERN GREAT
LAKES TONIGHT WHICH WILL BRING AN ACTIVE PERIOD OF WEATHER TO SE
MICHIGAN IN THE FORM OF INCREASING SHOWER COVERAGE LATER TONIGHT
AND THEN WIDESPREAD SHOWERS AND STRONG WIND FRIDAY. NORTH WIND IS
EXPECTED TO DEVELOP DURING FRIDAY AFTERNOON WITH GUSTS OF 30 TO 40
MPH LIKELY TO COMBINE WITH RAIN SHOWERS AND POSSIBLY A MIX OF SNOW
FOR HARSH WEATHER TOWARD SUNSET. GUSTS NEAR 45 MPH WIND ADVISORY
LEVELS HAVE GREATER POTENTIAL TOWARD FRIDAY EVENING WHEN THE BEST
ISENTROPIC DESCENT AND MID LEVEL SUBSIDENCE IS INDICATED IN MODEL
DATA AS THE LOW EXITS THE REGION. TIMING ON ANY ISSUANCE OF
HEADLINES REMAINS BEST SUITED FOR THE OVERNIGHT FORECAST PACKAGE.

UNTIL THEN...EVENING SURFACE ANALYSIS INDICATES LOW PRESSURE
ORGANIZING OVER THE STRAITS REGION WITH THE FIRST COLD FRONT OR
PREFRONTAL TROUGH EXTENDING THROUGH SOUTHERN WISCONSIN. THIS
PLACES WEAK SOUTHWEST FLOW AHEAD OF THESE FEATURES OVER LOWER
MICHIGAN THAT WILL BRING IN MILD AIR FOR THE BULK OF THE NIGHT AND
MAINTAIN TEMPS MOSTLY IN THE LOWER 40S. PLENTIFUL CLOUD COVER AND
POCKETS OF LIGHT RAIN ARE BEING FORCED BY GENTLE ISENTROPIC LIFT
AS THE LOW AND MID LEVEL THETA-E RIDGE FORMS AHEAD OF THE FRONT.
THE LATEST MODEL OUTPUT SHOWS THE THETA-E RIDGE BECOMING WELL
DEFINED DURING THE NIGHT REPRESENTING A SURGE OF LOW LEVEL
MOISTURE THAT WILL INTERACT WITH THE FIRST FRONTAL PASSAGE AND
DYNAMIC SUPPORT FROM THE UPPER LEVEL CIRCULATION. AN UPTICK IN
BOTH COVERAGE AND INTENSITY OF RAIN IS THEN EXPECTED ALONG THE
FRONT AS IT PASSES THROUGH SE MICHIGAN...FIRST IN THE TRI CITIES
AFTER MIDNIGHT AND THROUGH THE DETROIT AREA TOWARD SUNRISE
LASTING THROUGH ABOUT MID FRIDAY MORNING. THE GOING FORECAST LOOKS
SOLID RAMPING UP TO CATEGORICAL POPS DURING THIS TIME.

&&

.AVIATION...ISSUED 717 PM EDT THU OCT 30 2014

//DISCUSSION...

AN ACTIVE PERIOD OF WEATHER IS IN STORE FOR AVIATION INTERESTS AS A
STRONG LOW PRESSURE SYSTEM AND COLD FRONT MOVE THROUGH THE GREAT
LAKES MAINLY DURING FRIDAY. THE GREATEST IMPACT WILL BE IFR FRIDAY
AFTERNOON WITH 30 KNOT+ NORTH WIND BEHIND THE FRONT ACCOMPANIED
BY HEAVIER RAIN AND POSSIBLY A MIX OF RAIN AND SNOW TOWARD SUNSET.

THE BEGINNINGS OF THE SYSTEM ARE SEEN TONIGHT IN THE FORM LOW END
VFR CEILING AND A FEW SPRINKLES WHICH WILL TREND DOWNWARD DURING
THE OVERNIGHT. THE BEST CHANCE OF RAIN TONIGHT WILL ARRIVE WITH
THE LEADING SURFACE TROUGH TOWARD SUNRISE. THIS WILL BE FOLLOWED
BY A DRY SLOT THAT WILL LEAD TO A BREAK IN THE RAIN PATTERN FROM
MID FRIDAY MORNING THROUGH EARLY AFTERNOON BUT MVFR CEILING AND
PERHAPS SOME FOG RESTRICTION WILL PERSIST BETWEEN THE SURFACE
TROUGH AND PRIMARY COLD FRONT. THE PASSAGE OF THE FRONT WILL BRING
IN IFR IN HEAVIER RAIN AND LOW CEILING THAT WILL PERSIST INTO
FRIDAY EVENING POSSIBLY MIXING WITH SNOW BY LATE IN THE DAY.

FOR DTW... TURNING POINTS IN THE FORECAST WILL BE WITH THE
PREFRONTAL TROUGH AROUND SUNRISE WHICH WILL BRING IN RAIN...MVFR
CEILING...AND PERHAPS SOME FOG. THIS WILL BE FOLLOWED BY THE COLD
FRONT BY MID AFTERNOON WHICH WILL BRING IN IFR AND NORTH WIND
GUSTS POSSIBLY EXCEEDING 30 KNOTS ALONG WITH HEAVIER RAIN. A MIX
OF RAIN AND SNOW IS POSSIBLE LATE IN THE DAY WITH THE MIX LIKELY
LIMITING ACCUMULATION ON THE RELATIVELY WARM GROUND SURFACES.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE IN CEILING BELOW 5000 FEET TONIGHT...
  HIGH CONFIDENCE FRIDAY.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN LATE FRIDAY AND FRIDAY
  EVENING.

&&

.PREV DISCUSSION...ISSUED 422 PM EDT THU OCT 30 2014

SHORT TERM...THROUGH TONIGHT

UPPER LEVEL FEATURE OF NOTE IS A VIGOROUS...TIGHT PV ANOMALY
DROPPING SOUTHWARD INTO FAR NORTHERN MN AT 17Z. 12Z SUITE IN GOOD
AGREEMENT WITH THE PROGRESSION OF THIS FEATURE IN THE SHORT
TERM...PLACING IT NEAR THE WI/IL BORDER BY 12Z FRIDAY. CURRENTLY
OVER THE LOCAL AREA...SHORTWAVE RIDGING HAS PUSHED EAST OF THE
REGION...AND THE PATTERN WILL BE CHARACTERIZED BY GRADUAL HEIGHT
FALLS/WEAK WAA AS THE UPPER FEATURE NEARS. THIS WILL SUSTAIN THE
MIDLEVEL CLOUD DECK AND MAY ALLOW FOR SOME SPRINKLES/LIGHT SHOWERS
TO EXPAND SOUTHWARD WITH TIME INTO OUR REGION THROUGH THE EARLY PART
OF THE OVERNIGHT HOURS. ASCENT INCREASES FURTHER TOWARD THE END OF
THE PERIOD AS THE UPPER LEVEL FEATURE NEARS. SURFACE LOW WILL BE
ROUGHLY OVER SAGINAW BAY BY 12Z FRIDAY WITH A COLD FRONT EXTENDING
SWWD. THE HEAVIER BANDED PRECIP ASSOCIATED WITH FGEN CIRCULATION
SHOULD STILL MOSTLY BE TO OUR NORTHWEST IN THE COLDER POST-FRONTAL
AIR AT THAT POINT...BUT ASCENT SHOULD BE ENOUGH TO WARRANT
CATEGORICAL/LIKELY POPS AFTER 09Z OVER THE SAGINAW VALLEY/FLINT
REGIONS...RESPECTIVELY. LOWS WILL NOT DROP TOO MUCH TONIGHT WITH THE
INSULATING CLOUD DECK...EXPECTING MAINLY LOW 40S.

LONG TERM...FRIDAY THROUGH NEXT THURSDAY

UPPER WAVE OVER WESTERN ONTARIO WILL DIVE THROUGH THE WESTERN GREAT
LAKES AND THEN TOWARDS THE TENNESSEE VALLEY BY FRIDAY EVENING IN
RESPONSE TO AN AMPLIFICATION OF THE UPPER PATTERN OVER NORTH
AMERICA...WHICH WILL RESULT IN STRONG RIDGING EXTENDING UP THROUGH
CENTRAL CANADA. AS THE WAVE DROPS SOUTH...LOW PRESSURE NOW NORTH OF
LAKE SUPERIOR WILL DEEPEN AS IT TRACKS THROUGH LAKE HURON FRIDAY
MORNING AND INTO LAKE ERIE FRIDAY EVENING. THE PASSAGE OF THIS
SYSTEM THROUGH THE AREA WILL PULL AN ARCTIC COLD FRONT DOWN THROUGH
THE AREA. THE FRONT IS CURRENTLY DROPPING THROUGH NORTHERN
MINNESOTA...WHERE SURFACE OBSERVATIONS HAVE BEEN SHOWING GUSTY
WINDS...FALLING TEMPERATURES AND A CHANGE OVER IN PRECIPITATION TYPE
FROM RAIN TO SNOW.

PRECIPITATION SHOULD BE WORKING DOWN INTO THE AREA AT THE START OF
THE DAY TOMORROW AS THE FRONT APPROACHES. EXPECTING BEST COVERAGE
AND PRECIP RATES AS DEFORMATION AXIS AND EVEN A WEAK TROWAL ON THE
NORTH SIDE OF THE SYSTEM DROPS ACROSS SOUTHEAST MICHIGAN FROM EARLY
AFTERNOON THROUGH EVENING. DEFORMATION AXIS IS EXPECTED TO LINGER A
BIT LONGER OVER THE FAR EASTERN PORTION OF MICHIGAN FRIDAY NIGHT AS
THE LOW TAKES ON MORE OF A SOUTHERLY TRAJECTORY ACROSS LAKE ERIE.
ARCTIC FRONTAL BOUNDARY WILL ALSO DROP ACROSS THE AREA...WITH TIMING
CURRENTLY EXPECTED FROM VERY LATE MORNING THROUGH EARLY EVENING.
MODEL FORECAST SOUNDINGS CONTINUE TO SUPPORT A CHANGEOVER IN
PRECIPITATION TYPE FROM RAIN TO SNOW AS COLDER AIR WORKS IN BEHIND
THE FRONT. ACCUMULATIONS IF ANY LOOK LIGHT AT THIS TIME...AND
CONFINED MAINLY TO GRASSY AND ELEVATED SURFACES. WILL HAVE TO WATCH
LAKE EFFECT POTENTIAL FROM OFF LAKE HURON BEHIND THE FRONT WITH
STEEP LAPSE RATES DEVELOPING OVER THE WARMER LAKE WATERS AND STRONG
NORTHERLY FLOW. LAKE-MODIFIED AIRMASS ALSO MAKES PRECIP TYPE A
LITTLE MORE CHALLENGING...AS IT COULD KEEP PRECIP RAIN OR A MIX OF
RAIN/SNOW OVER THE EASTERN HALF OF THE AREA.

OTHER CONCERN TOMORROW WILL BE THE STRONG CORE OF 50 KT WINDS AT 925-
850MB WORKING DOWN ON THE BACKSIDE OF THE SYSTEM FROM LATE AFTERNOON
INTO THE OVERNIGHT. FORECAST SOUNDINGS FROM BOTH THE NAM AND GFS
SHOW THE BOUNDARY LAYER SHOULD BE SUFFICIENTLY DEEP ENOUGH BEHIND
THE FRONT FOR GUSTS TO 45 OR PERHAPS EVEN 50 MPH TO WORK DOWN TO THE
SURFACE AS LAPSE RATES ALSO STEEPEN. MODELS HAVE WAVERED A BIT ON
THIS OVER THE PAST FEW RUNS...AND DO NOT SHOW STRONG DESCENT LIKE WE
HAVE HAD WITH WIND EVENTS IN THE PAST. WILL WATCH FOR ANOTHER ROUND
OF MODEL RUNS...BUT A WIND ADVISORY MAY BE REQUIRED.

DRIER AIR LOOKS TO ARRIVE SATURDAY AFTERNOON AS RIDGING BUILDS INTO
THE GREAT LAKES AHEAD OF THE AMPLIFIED RIDGE AXIS OVER THE PLAINS.
THE DRIER AIR AND LOWERING INVERSION HEIGHTS SHOULD PUT AN END TO
LAKE EFFECT FROM OFF LAKE HURON BY AFTERNOON. POST-FRONTAL
TEMPERATURES WILL BE QUITE COLD...WITH HIGHS ONLY IN THE UPPER 30S
AND LOW 40S. CLEAR SKIES AND LIGHT WINDS SATURDAY NIGHT WILL SET US
UP FOR THE COLDEST NIGHT OF THE SEASON SO FAR...WITH LOWS SOLIDLY IN
THE 20S.

AS SURFACE HIGH PRESSURE SHIFTS TOWARDS THE EAST ON SUNDAY...FLOW
TURNS SOUTHERLY AND SOUTHEAST MICHIGAN RECOVERS FROM THE FRIGID
CONDITIONS FROM THE PREVIOUS TWO DAYS. HIGHS WILL REACH THE MID 50S
BY TUESDAY. A SOUTHWEST JET WILL THEN USHER IN PACIFIC MOISTURE TO
COMBINE WITH A FRONTAL SYSTEM TUESDAY INTO EARLY WEDNESDAY. LOCATION
AND FORWARD SPEED OF THE FRONT IS UP FOR DEBATE...SO THERE COULD A
LARGE TEMP SWING/ERROR ON DAYS 6-7.

MARINE...LOW PRESSURE WILL DEEPEN AS IT TRACKS FROM LAKE SUPERIOR
TO SOUTH OF LAKE ERIE BY FRIDAY EVENING. AS THE SYSTEM DROPS THROUGH
THE CENTRAL GREAT LAKES...IT WILL PULL AN ARCTIC COLD FRONT DOWN
ACROSS THE REGION. THE COLD AIR WILL FILL IN OVER THE WARMER LAKE
WATERS...ALLOWING A STRONG CORE OF WINDS ALOFT TO MIX DOWN TO THE
LAKE SURFACE. GALE FORCE WIND GUSTS ARE EXPECTED TO DEVELOP OVER
LAKE HURON ON FRIDAY...AND SPREAD TO LAKE ST CLAIR AND WESTERN LAKE
ERIE BY FRIDAY NIGHT. THE STRONG AND PERSISTENT NORTHERLY WINDS WILL
ALLOW WAVE HEIGHTS TO BUILD AS HIGH AS 15 FEET OVER THE SOUTHERN
PORTION OF LAKE HURON BY FRIDAY EVENING. WINDS WILL GRADUALLY
DIMINISH ON SATURDAY AS A RIDGE OF HIGH PRESSURE SLIDES INTO THE
AREA. LARGE WAVES OVER SOUTHERN LAKE HURON WILL BE SLOW TO SUBSIDE
HOWEVER...NOT DROPPING BELOW 4 FEET UNTIL SATURDAY EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...GALE WARNING FROM 11 AM FRIDAY TO 8 AM EDT SATURDAY FOR LHZ363-421-
     422-441-462.

     GALE WARNING FROM 2 PM FRIDAY TO 10 AM EDT SATURDAY FOR LHZ442-443-
     463-464.

     GALE WARNING FROM 8 AM TO 8 PM EDT FRIDAY FOR LHZ361.

     GALE WARNING FROM 8 AM FRIDAY TO 2 AM EDT SATURDAY FOR LHZ362.

LAKE ST CLAIR...GALE WARNING FROM 8 PM FRIDAY TO 10 AM EDT SATURDAY FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING FROM 8 PM FRIDAY TO 10 AM EDT SATURDAY FOR LEZ444.

&&

$$

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


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





000
FXUS63 KDTX 302317
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
717 PM EDT THU OCT 30 2014
.AVIATION...

//DISCUSSION...

AN ACTIVE PERIOD OF WEATHER IS IN STORE FOR AVIATION INTERESTS AS A
STRONG LOW PRESSURE SYSTEM AND COLD FRONT MOVE THROUGH THE GREAT
LAKES MAINLY DURING FRIDAY. THE GREATEST IMPACT WILL BE IFR FRIDAY
AFTERNOON WITH 30 KNOT+ NORTH WIND BEHIND THE FRONT ACCOMPANIED
BY HEAVIER RAIN AND POSSIBLY A MIX OF RAIN AND SNOW TOWARD SUNSET.

THE BEGINNINGS OF THE SYSTEM ARE SEEN TONIGHT IN THE FORM LOW END
VFR CEILING AND A FEW SPRINKLES WHICH WILL TREND DOWNWARD DURING
THE OVERNIGHT. THE BEST CHANCE OF RAIN TONIGHT WILL ARRIVE WITH
THE LEADING SURFACE TROUGH TOWARD SUNRISE. THIS WILL BE FOLLOWED
BY A DRY SLOT THAT WILL LEAD TO A BREAK IN THE RAIN PATTERN FROM
MID FRIDAY MORNING THROUGH EARLY AFTERNOON BUT MVFR CEILING AND
PERHAPS SOME FOG RESTRICTION WILL PERSIST BETWEEN THE SURFACE
TROUGH AND PRIMARY COLD FRONT. THE PASSAGE OF THE FRONT WILL BRING
IN IFR IN HEAVIER RAIN AND LOW CEILING THAT WILL PERSIST INTO
FRIDAY EVENING POSSIBLY MIXING WITH SNOW BY LATE IN THE DAY.

FOR DTW... TURNING POINTS IN THE FORECAST WILL BE WITH THE
PREFRONTAL TROUGH AROUND SUNRISE WHICH WILL BRING IN RAIN...MVFR
CEILING...AND PERHAPS SOME FOG. THIS WILL BE FOLLOWED BY THE COLD
FRONT BY MID AFTERNOON WHICH WILL BRING IN IFR AND NORTH WIND
GUSTS POSSIBLY EXCEEDING 30 KNOTS ALONG WITH HEAVIER RAIN. A MIX
OF RAIN AND SNOW IS POSSIBLE LATE IN THE DAY WITH THE MIX LIKELY
LIMITING ACCUMULATION ON THE RELATIVELY WARM GROUND SURFACES.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE IN CEILING BELOW 5000 FEET TONIGHT...
  HIGH CONFIDENCE FRIDAY.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN LATE FRIDAY AND FRIDAY
  EVENING.

&&

.PREV DISCUSSION...ISSUED 422 PM EDT THU OCT 30 2014

SHORT TERM...THROUGH TONIGHT

UPPER LEVEL FEATURE OF NOTE IS A VIGOROUS...TIGHT PV ANOMALY
DROPPING SOUTHWARD INTO FAR NORTHERN MN AT 17Z. 12Z SUITE IN GOOD
AGREEMENT WITH THE PROGRESSION OF THIS FEATURE IN THE SHORT
TERM...PLACING IT NEAR THE WI/IL BORDER BY 12Z FRIDAY. CURRENTLY
OVER THE LOCAL AREA...SHORTWAVE RIDGING HAS PUSHED EAST OF THE
REGION...AND THE PATTERN WILL BE CHARACTERIZED BY GRADUAL HEIGHT
FALLS/WEAK WAA AS THE UPPER FEATURE NEARS. THIS WILL SUSTAIN THE
MIDLEVEL CLOUD DECK AND MAY ALLOW FOR SOME SPRINKLES/LIGHT SHOWERS
TO EXPAND SOUTHWARD WITH TIME INTO OUR REGION THROUGH THE EARLY PART
OF THE OVERNIGHT HOURS. ASCENT INCREASES FURTHER TOWARD THE END OF
THE PERIOD AS THE UPPER LEVEL FEATURE NEARS. SURFACE LOW WILL BE
ROUGHLY OVER SAGINAW BAY BY 12Z FRIDAY WITH A COLD FRONT EXTENDING
SWWD. THE HEAVIER BANDED PRECIP ASSOCIATED WITH FGEN CIRCULATION
SHOULD STILL MOSTLY BE TO OUR NORTHWEST IN THE COLDER POST-FRONTAL
AIR AT THAT POINT...BUT ASCENT SHOULD BE ENOUGH TO WARRANT
CATEGORICAL/LIKELY POPS AFTER 09Z OVER THE SAGINAW VALLEY/FLINT
REGIONS...RESPECTIVELY. LOWS WILL NOT DROP TOO MUCH TONIGHT WITH THE
INSULATING CLOUD DECK...EXPECTING MAINLY LOW 40S.

LONG TERM...FRIDAY THROUGH NEXT THURSDAY

UPPER WAVE OVER WESTERN ONTARIO WILL DIVE THROUGH THE WESTERN GREAT
LAKES AND THEN TOWARDS THE TENNESSEE VALLEY BY FRIDAY EVENING IN
RESPONSE TO AN AMPLIFICATION OF THE UPPER PATTERN OVER NORTH
AMERICA...WHICH WILL RESULT IN STRONG RIDGING EXTENDING UP THROUGH
CENTRAL CANADA. AS THE WAVE DROPS SOUTH...LOW PRESSURE NOW NORTH OF
LAKE SUPERIOR WILL DEEPEN AS IT TRACKS THROUGH LAKE HURON FRIDAY
MORNING AND INTO LAKE ERIE FRIDAY EVENING. THE PASSAGE OF THIS
SYSTEM THROUGH THE AREA WILL PULL AN ARCTIC COLD FRONT DOWN THROUGH
THE AREA. THE FRONT IS CURRENTLY DROPPING THROUGH NORTHERN
MINNESOTA...WHERE SURFACE OBSERVATIONS HAVE BEEN SHOWING GUSTY
WINDS...FALLING TEMPERATURES AND A CHANGE OVER IN PRECIPITATION TYPE
FROM RAIN TO SNOW.

PRECIPITATION SHOULD BE WORKING DOWN INTO THE AREA AT THE START OF
THE DAY TOMORROW AS THE FRONT APPROACHES. EXPECTING BEST COVERAGE
AND PRECIP RATES AS DEFORMATION AXIS AND EVEN A WEAK TROWAL ON THE
NORTH SIDE OF THE SYSTEM DROPS ACROSS SOUTHEAST MICHIGAN FROM EARLY
AFTERNOON THROUGH EVENING. DEFORMATION AXIS IS EXPECTED TO LINGER A
BIT LONGER OVER THE FAR EASTERN PORTION OF MICHIGAN FRIDAY NIGHT AS
THE LOW TAKES ON MORE OF A SOUTHERLY TRAJECTORY ACROSS LAKE ERIE.
ARCTIC FRONTAL BOUNDARY WILL ALSO DROP ACROSS THE AREA...WITH TIMING
CURRENTLY EXPECTED FROM VERY LATE MORNING THROUGH EARLY EVENING.
MODEL FORECAST SOUNDINGS CONTINUE TO SUPPORT A CHANGEOVER IN
PRECIPITATION TYPE FROM RAIN TO SNOW AS COLDER AIR WORKS IN BEHIND
THE FRONT. ACCUMULATIONS IF ANY LOOK LIGHT AT THIS TIME...AND
CONFINED MAINLY TO GRASSY AND ELEVATED SURFACES. WILL HAVE TO WATCH
LAKE EFFECT POTENTIAL FROM OFF LAKE HURON BEHIND THE FRONT WITH
STEEP LAPSE RATES DEVELOPING OVER THE WARMER LAKE WATERS AND STRONG
NORTHERLY FLOW. LAKE-MODIFIED AIRMASS ALSO MAKES PRECIP TYPE A
LITTLE MORE CHALLENGING...AS IT COULD KEEP PRECIP RAIN OR A MIX OF
RAIN/SNOW OVER THE EASTERN HALF OF THE AREA.

OTHER CONCERN TOMORROW WILL BE THE STRONG CORE OF 50 KT WINDS AT 925-
850MB WORKING DOWN ON THE BACKSIDE OF THE SYSTEM FROM LATE AFTERNOON
INTO THE OVERNIGHT. FORECAST SOUNDINGS FROM BOTH THE NAM AND GFS
SHOW THE BOUNDARY LAYER SHOULD BE SUFFICIENTLY DEEP ENOUGH BEHIND
THE FRONT FOR GUSTS TO 45 OR PERHAPS EVEN 50 MPH TO WORK DOWN TO THE
SURFACE AS LAPSE RATES ALSO STEEPEN. MODELS HAVE WAVERED A BIT ON
THIS OVER THE PAST FEW RUNS...AND DO NOT SHOW STRONG DESCENT LIKE WE
HAVE HAD WITH WIND EVENTS IN THE PAST. WILL WATCH FOR ANOTHER ROUND
OF MODEL RUNS...BUT A WIND ADVISORY MAY BE REQUIRED.

DRIER AIR LOOKS TO ARRIVE SATURDAY AFTERNOON AS RIDGING BUILDS INTO
THE GREAT LAKES AHEAD OF THE AMPLIFIED RIDGE AXIS OVER THE PLAINS.
THE DRIER AIR AND LOWERING INVERSION HEIGHTS SHOULD PUT AN END TO
LAKE EFFECT FROM OFF LAKE HURON BY AFTERNOON. POST-FRONTAL
TEMPERATURES WILL BE QUITE COLD...WITH HIGHS ONLY IN THE UPPER 30S
AND LOW 40S. CLEAR SKIES AND LIGHT WINDS SATURDAY NIGHT WILL SET US
UP FOR THE COLDEST NIGHT OF THE SEASON SO FAR...WITH LOWS SOLIDLY IN
THE 20S.

AS SURFACE HIGH PRESSURE SHIFTS TOWARDS THE EAST ON SUNDAY...FLOW
TURNS SOUTHERLY AND SOUTHEAST MICHIGAN RECOVERS FROM THE FRIGID
CONDITIONS FROM THE PREVIOUS TWO DAYS. HIGHS WILL REACH THE MID 50S
BY TUESDAY. A SOUTHWEST JET WILL THEN USHER IN PACIFIC MOISTURE TO
COMBINE WITH A FRONTAL SYSTEM TUESDAY INTO EARLY WEDNESDAY. LOCATION
AND FORWARD SPEED OF THE FRONT IS UP FOR DEBATE...SO THERE COULD A
LARGE TEMP SWING/ERROR ON DAYS 6-7.

MARINE...LOW PRESSURE WILL DEEPEN AS IT TRACKS FROM LAKE SUPERIOR
TO SOUTH OF LAKE ERIE BY FRIDAY EVENING. AS THE SYSTEM DROPS THROUGH
THE CENTRAL GREAT LAKES...IT WILL PULL AN ARCTIC COLD FRONT DOWN
ACROSS THE REGION. THE COLD AIR WILL FILL IN OVER THE WARMER LAKE
WATERS...ALLOWING A STRONG CORE OF WINDS ALOFT TO MIX DOWN TO THE
LAKE SURFACE. GALE FORCE WIND GUSTS ARE EXPECTED TO DEVELOP OVER
LAKE HURON ON FRIDAY...AND SPREAD TO LAKE ST CLAIR AND WESTERN LAKE
ERIE BY FRIDAY NIGHT. THE STRONG AND PERSISTENT NORTHERLY WINDS WILL
ALLOW WAVE HEIGHTS TO BUILD AS HIGH AS 15 FEET OVER THE SOUTHERN
PORTION OF LAKE HURON BY FRIDAY EVENING. WINDS WILL GRADUALLY
DIMINISH ON SATURDAY AS A RIDGE OF HIGH PRESSURE SLIDES INTO THE
AREA. LARGE WAVES OVER SOUTHERN LAKE HURON WILL BE SLOW TO SUBSIDE
HOWEVER...NOT DROPPING BELOW 4 FEET UNTIL SATURDAY EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WARNING FROM 11 AM FRIDAY TO 8 AM EDT SATURDAY FOR LHZ363-421-
     422-441-462.

     GALE WARNING FROM 2 PM FRIDAY TO 10 AM EDT SATURDAY FOR LHZ442-443-
     463-464.

     GALE WARNING FROM 8 AM TO 8 PM EDT FRIDAY FOR LHZ361.

     GALE WARNING FROM 8 AM FRIDAY TO 2 AM EDT SATURDAY FOR LHZ362.

LAKE ST CLAIR...GALE WARNING FROM 8 PM FRIDAY TO 10 AM EDT SATURDAY FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING FROM 8 PM FRIDAY TO 10 AM EDT SATURDAY FOR LEZ444.

&&

$$

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


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





000
FXUS63 KDTX 302022
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
422 PM EDT THU OCT 30 2014

.SHORT TERM...THROUGH TONIGHT

UPPER LEVEL FEATURE OF NOTE IS A VIGOROUS...TIGHT PV ANOMALY
DROPPING SOUTHWARD INTO FAR NORTHERN MN AT 17Z. 12Z SUITE IN GOOD
AGREEMENT WITH THE PROGRESSION OF THIS FEATURE IN THE SHORT
TERM...PLACING IT NEAR THE WI/IL BORDER BY 12Z FRIDAY. CURRENTLY
OVER THE LOCAL AREA...SHORTWAVE RIDGING HAS PUSHED EAST OF THE
REGION...AND THE PATTERN WILL BE CHARACTERIZED BY GRADUAL HEIGHT
FALLS/WEAK WAA AS THE UPPER FEATURE NEARS. THIS WILL SUSTAIN THE
MIDLEVEL CLOUD DECK AND MAY ALLOW FOR SOME SPRINKLES/LIGHT SHOWERS
TO EXPAND SOUTHWARD WITH TIME INTO OUR REGION THROUGH THE EARLY PART
OF THE OVERNIGHT HOURS. ASCENT INCREASES FURTHER TOWARD THE END OF
THE PERIOD AS THE UPPER LEVEL FEATURE NEARS. SURFACE LOW WILL BE
ROUGHLY OVER SAGINAW BAY BY 12Z FRIDAY WITH A COLD FRONT EXTENDING
SWWD. THE HEAVIER BANDED PRECIP ASSOCIATED WITH FGEN CIRCULATION
SHOULD STILL MOSTLY BE TO OUR NORTHWEST IN THE COLDER POST-FRONTAL
AIR AT THAT POINT...BUT ASCENT SHOULD BE ENOUGH TO WARRANT
CATEGORICAL/LIKELY POPS AFTER 09Z OVER THE SAGINAW VALLEY/FLINT
REGIONS...RESPECTIVELY. LOWS WILL NOT DROP TOO MUCH TONIGHT WITH THE
INSULATING CLOUD DECK...EXPECTING MAINLY LOW 40S.

&&

.LONG TERM...FRIDAY THROUGH NEXT THURSDAY

UPPER WAVE OVER WESTERN ONTARIO WILL DIVE THROUGH THE WESTERN GREAT
LAKES AND THEN TOWARDS THE TENNESSEE VALLEY BY FRIDAY EVENING IN
RESPONSE TO AN AMPLIFICATION OF THE UPPER PATTERN OVER NORTH
AMERICA...WHICH WILL RESULT IN STRONG RIDGING EXTENDING UP THROUGH
CENTRAL CANADA. AS THE WAVE DROPS SOUTH...LOW PRESSURE NOW NORTH OF
LAKE SUPERIOR WILL DEEPEN AS IT TRACKS THROUGH LAKE HURON FRIDAY
MORNING AND INTO LAKE ERIE FRIDAY EVENING. THE PASSAGE OF THIS
SYSTEM THROUGH THE AREA WILL PULL AN ARCTIC COLD FRONT DOWN THROUGH
THE AREA. THE FRONT IS CURRENTLY DROPPING THROUGH NORTHERN
MINNESOTA...WHERE SURFACE OBSERVATIONS HAVE BEEN SHOWING GUSTY
WINDS...FALLING TEMPERATURES AND A CHANGE OVER IN PRECIPITATION TYPE
FROM RAIN TO SNOW.

PRECIPITATION SHOULD BE WORKING DOWN INTO THE AREA AT THE START OF
THE DAY TOMORROW AS THE FRONT APPROACHES. EXPECTING BEST COVERAGE
AND PRECIP RATES AS DEFORMATION AXIS AND EVEN A WEAK TROWAL ON THE
NORTH SIDE OF THE SYSTEM DROPS ACROSS SOUTHEAST MICHIGAN FROM EARLY
AFTERNOON THROUGH EVENING. DEFORMATION AXIS IS EXPECTED TO LINGER A
BIT LONGER OVER THE FAR EASTERN PORTION OF MICHIGAN FRIDAY NIGHT AS
THE LOW TAKES ON MORE OF A SOUTHERLY TRAJECTORY ACROSS LAKE ERIE.
ARCTIC FRONTAL BOUNDARY WILL ALSO DROP ACROSS THE AREA...WITH TIMING
CURRENTLY EXPECTED FROM VERY LATE MORNING THROUGH EARLY EVENING.
MODEL FORECAST SOUNDINGS CONTINUE TO SUPPORT A CHANGEOVER IN
PRECIPITATION TYPE FROM RAIN TO SNOW AS COLDER AIR WORKS IN BEHIND
THE FRONT. ACCUMULATIONS IF ANY LOOK LIGHT AT THIS TIME...AND
CONFINED MAINLY TO GRASSY AND ELEVATED SURFACES. WILL HAVE TO WATCH
LAKE EFFECT POTENTIAL FROM OFF LAKE HURON BEHIND THE FRONT WITH
STEEP LAPSE RATES DEVELOPING OVER THE WARMER LAKE WATERS AND STRONG
NORTHERLY FLOW. LAKE-MODIFIED AIRMASS ALSO MAKES PRECIP TYPE A
LITTLE MORE CHALLENGING...AS IT COULD KEEP PRECIP RAIN OR A MIX OF
RAIN/SNOW OVER THE EASTERN HALF OF THE AREA.

OTHER CONCERN TOMORROW WILL BE THE STRONG CORE OF 50 KT WINDS AT 925-
850MB WORKING DOWN ON THE BACKSIDE OF THE SYSTEM FROM LATE AFTERNOON
INTO THE OVERNIGHT. FORECAST SOUNDINGS FROM BOTH THE NAM AND GFS
SHOW THE BOUNDARY LAYER SHOULD BE SUFFICIENTLY DEEP ENOUGH BEHIND
THE FRONT FOR GUSTS TO 45 OR PERHAPS EVEN 50 MPH TO WORK DOWN TO THE
SURFACE AS LAPSE RATES ALSO STEEPEN. MODELS HAVE WAVERED A BIT ON
THIS OVER THE PAST FEW RUNS...AND DO NOT SHOW STRONG DESCENT LIKE WE
HAVE HAD WITH WIND EVENTS IN THE PAST. WILL WATCH FOR ANOTHER ROUND
OF MODEL RUNS...BUT A WIND ADVISORY MAY BE REQUIRED.

DRIER AIR LOOKS TO ARRIVE SATURDAY AFTERNOON AS RIDGING BUILDS INTO
THE GREAT LAKES AHEAD OF THE AMPLIFIED RIDGE AXIS OVER THE PLAINS.
THE DRIER AIR AND LOWERING INVERSION HEIGHTS SHOULD PUT AN END TO
LAKE EFFECT FROM OFF LAKE HURON BY AFTERNOON. POST-FRONTAL
TEMPERATURES WILL BE QUITE COLD...WITH HIGHS ONLY IN THE UPPER 30S
AND LOW 40S. CLEAR SKIES AND LIGHT WINDS SATURDAY NIGHT WILL SET US
UP FOR THE COLDEST NIGHT OF THE SEASON SO FAR...WITH LOWS SOLIDLY IN
THE 20S.

AS SURFACE HIGH PRESSURE SHIFTS TOWARDS THE EAST ON SUNDAY...FLOW
TURNS SOUTHERLY AND SOUTHEAST MICHIGAN RECOVERS FROM THE FRIGID
CONDITIONS FROM THE PREVIOUS TWO DAYS. HIGHS WILL REACH THE MID 50S
BY TUESDAY. A SOUTHWEST JET WILL THEN USHER IN PACIFIC MOISTURE TO
COMBINE WITH A FRONTAL SYSTEM TUESDAY INTO EARLY WEDNESDAY. LOCATION
AND FORWARD SPEED OF THE FRONT IS UP FOR DEBATE...SO THERE COULD A
LARGE TEMP SWING/ERROR ON DAYS 6-7.

&&

.MARINE...LOW PRESSURE WILL DEEPEN AS IT TRACKS FROM LAKE SUPERIOR
TO SOUTH OF LAKE ERIE BY FRIDAY EVENING. AS THE SYSTEM DROPS THROUGH
THE CENTRAL GREAT LAKES...IT WILL PULL AN ARCTIC COLD FRONT DOWN
ACROSS THE REGION. THE COLD AIR WILL FILL IN OVER THE WARMER LAKE
WATERS...ALLOWING A STRONG CORE OF WINDS ALOFT TO MIX DOWN TO THE
LAKE SURFACE. GALE FORCE WIND GUSTS ARE EXPECTED TO DEVELOP OVER
LAKE HURON ON FRIDAY...AND SPREAD TO LAKE ST CLAIR AND WESTERN LAKE
ERIE BY FRIDAY NIGHT. THE STRONG AND PERSISTENT NORTHERLY WINDS WILL
ALLOW WAVE HEIGHTS TO BUILD AS HIGH AS 15 FEET OVER THE SOUTHERN
PORTION OF LAKE HURON BY FRIDAY EVENING. WINDS WILL GRADUALLY
DIMINISH ON SATURDAY AS A RIDGE OF HIGH PRESSURE SLIDES INTO THE
AREA. LARGE WAVES OVER SOUTHERN LAKE HURON WILL BE SLOW TO SUBSIDE
HOWEVER...NOT DROPPING BELOW 4 FEET UNTIL SATURDAY EVENING.

&&

.AVIATION...ISSUED 120 PM EDT THU OCT 30 2014

//DISCUSSION...

FAIRLY SOLID VFR STRATOCU DECK IN PLACE OVER MUCH OF LOWER MI SHOULD
PERSIST INTO THE EVENING. OTHERWISE BENIGN CONDITIONS EXPECTED THE
REST OF THE DAY INTO THE EARLY OVERNIGHT HOURS. ATTENTION THEN TURNS
TO A STRONG SYSTEM DROPPING SOUTHWARD OUT OF SOUTHERN CANADA. THIS
SYSTEM WILL DRAG A STRONG FRONT THROUGH THE REGION ON FRIDAY WITH
PERIODS OF RAIN DEVELOPING. THE HEAVIER PRECIPITATION WILL OCCUR
BEHIND THE FRONT...THOUGH SOME LIGHER PRECIPITATION WILL BEGIN LATE
TONIGHT...SPREADING SOUTHEASTWARD THROUGH THE TERMINAL CORRIDOR.
BANDS OF HEAVIER RAIN ARE POSSIBLE DURING THE DAY FRIDAY...AGAIN
SPREADING SOUTHEASTWARD. THE RAIN MAY MIX WITH/TURN TO SNOW FRIDAY
TOWARD THE END OF THE TAF PERIOD AS COLDER AIR WRAPS IN. THE
STRONGER WINDS SHOULD HOLD OFF UNTIL AFTER THE 24 HOUR TAF
PERIOD...BUT IFR CIGS/VIS ARE POSSIBLE FRIDAY. PREFER TO LEAVE IFR
AND SNOW MENTION OUT OF THE TAFS FOR THIS ISSUANCE AND REFINE IN
SUBSEQUENT FORECASTS.

FOR DTW...SUB-5KFT DECK IN PLACE THIS AFTERNOON. SOME UNCERTAINTY
WITH WHETHER BASES WILL LIFT AND/OR CIGS WILL SCATTER FOR A PERIOD
LATE THIS EVENING AS INCREASING ASCENT ACTS TO RAISE THE INVERSION.
THIS SCENARIO IS SUPPORTED BY SOME CLEARING OVER LAKE
MI/INDIANA...HOWEVER WILL SIDE WITH FORECAST SOUNDINGS WHICH DEPICT
CLOUD BASES REMAINING STEADY.

ANY MEANINGFUL PRECIPITATION LOOKS TO HOLD OFF UNTIL FRIDAY MORNING
AS THE UPPER SYSTEM AND COLD FRONT NEAR. BANDS OF HEAVIER RAIN ARE
POSSIBLE DURING THE AFTERNOON AND EVENING WITH IFR RESTRICTIONS
POSSIBLE. THE RAIN WILL TEND TO MIX WITH SNOW TOWARD FRIDAY EVENING
AS WINDS TURN NORTHERLY AND BECOME QUITE GUSTY. LITTLE TO NO
ACCUMULATION IS EXPECTED. WILL ADD MORE DETAIL WITH SUBSEQUENT
FORECASTS.


//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5KFT THROUGH THIS
  EVENING...MEDIUM CONFIDENCE OVERNIGHT...HIGH CONFIDENCE FRIDAY.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN FRIDAY EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WARNING FROM 11 AM FRIDAY TO 8 AM EDT SATURDAY FOR LHZ363-421-
     422-441-462.

     GALE WARNING FROM 2 PM FRIDAY TO 10 AM EDT SATURDAY FOR LHZ442-443-
     463-464.

     GALE WARNING FROM 8 AM TO 8 PM EDT FRIDAY FOR LHZ361.

     GALE WARNING FROM 8 AM FRIDAY TO 2 AM EDT SATURDAY FOR LHZ362.

LAKE ST CLAIR...GALE WARNING FROM 8 PM FRIDAY TO 10 AM EDT SATURDAY FOR LCZ460.

MICHIGAN WATERS OF LAKE ERIE...GALE WARNING FROM 8 PM FRIDAY TO 10 AM EDT SATURDAY FOR LEZ444.

&&

$$

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


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





000
FXUS63 KDTX 301720
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
120 PM EDT THU OCT 30 2014


.AVIATION...

//DISCUSSION...

FAIRLY SOLID VFR STRATOCU DECK IN PLACE OVER MUCH OF LOWER MI SHOULD
PERSIST INTO THE EVENING. OTHERWISE BENIGN CONDITIONS EXPECTED THE
REST OF THE DAY INTO THE EARLY OVERNIGHT HOURS. ATTENTION THEN TURNS
TO A STRONG SYSTEM DROPPING SOUTHWARD OUT OF SOUTHERN CANADA. THIS
SYSTEM WILL DRAG A STRONG FRONT THROUGH THE REGION ON FRIDAY WITH
PERIODS OF RAIN DEVELOPING. THE HEAVIER PRECIPITATION WILL OCCUR
BEHIND THE FRONT...THOUGH SOME LIGHER PRECIPITATION WILL BEGIN LATE
TONIGHT...SPREADING SOUTHEASTWARD THROUGH THE TERMINAL CORRIDOR.
BANDS OF HEAVIER RAIN ARE POSSIBLE DURING THE DAY FRIDAY...AGAIN
SPREADING SOUTHEASTWARD. THE RAIN MAY MIX WITH/TURN TO SNOW FRIDAY
TOWARD THE END OF THE TAF PERIOD AS COLDER AIR WRAPS IN. THE
STRONGER WINDS SHOULD HOLD OFF UNTIL AFTER THE 24 HOUR TAF
PERIOD...BUT IFR CIGS/VIS ARE POSSIBLE FRIDAY. PREFER TO LEAVE IFR
AND SNOW MENTION OUT OF THE TAFS FOR THIS ISSUANCE AND REFINE IN
SUBSEQUENT FORECASTS.

FOR DTW...SUB-5KFT DECK IN PLACE THIS AFTERNOON. SOME UNCERTAINTY
WITH WHETHER BASES WILL LIFT AND/OR CIGS WILL SCATTER FOR A PERIOD
LATE THIS EVENING AS INCREASING ASCENT ACTS TO RAISE THE INVERSION.
THIS SCENARIO IS SUPPORTED BY SOME CLEARING OVER LAKE
MI/INDIANA...HOWEVER WILL SIDE WITH FORECAST SOUNDINGS WHICH DEPICT
CLOUD BASES REMAINING STEADY.

ANY MEANINGFUL PRECIPITATION LOOKS TO HOLD OFF UNTIL FRIDAY MORNING
AS THE UPPER SYSTEM AND COLD FRONT NEAR. BANDS OF HEAVIER RAIN ARE
POSSIBLE DURING THE AFTERNOON AND EVENING WITH IFR RESTRICTIONS
POSSIBLE. THE RAIN WILL TEND TO MIX WITH SNOW TOWARD FRIDAY EVENING
AS WINDS TURN NORTHERLY AND BECOME QUITE GUSTY. LITTLE TO NO
ACCUMULATION IS EXPECTED. WILL ADD MORE DETAIL WITH SUBSEQUENT
FORECASTS.


//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CEILINGS BELOW 5KFT THROUGH THIS
  EVENING...MEDIUM CONFIDENCE OVERNIGHT...HIGH CONFIDENCE FRIDAY.

* MEDIUM CONFIDENCE IN SNOW MIXING WITH RAIN FRIDAY EVENING.

&&

.PREV DISCUSSION...ISSUED 335 AM EDT THU OCT 30 2014

SHORT TERM...TODAY AND TONIGHT

SHORTWAVE RIDGING WILL TRACK EAST THROUGH THE CENTRAL GREAT LAKES
THIS MORNING...KEEPING WINDS CALM AND CONDITIONS RELATIVELY DRY
DURING THE DAYTIME HOURS. DESPITE MORNING SUNSHINE...CLOUDS WILL
INCREASE THROUGH THE DAY AS MOISTURE ADVECTS IN FROM THE WEST AHEAD
OF A DEVELOPING LOW PRESSURE SYSTEM DIVING SOUTH FROM CANADA TOWARDS
THE NORTHWESTERN GREAT LAKES THIS AFTERNOON. GIVEN THE MID AND UPPER
LEVEL WAVE WILL STILL BE FAR TO THE NORTHWEST...RAIN WITH THIS
SYSTEM IS NOT EXPECTED TO AFFECT THE AREA TODAY. WITH COLD AIR STILL
IN PLACE AND INCREASING CLOUDS...HIGHS WILL GENERALLY BE AROUND 50
DEGREES...WITH SOME MID 40S POSSIBLE OVER THE NORTHERN THUMB REGION.

THE POSITIVELY TILTED MID LEVEL TROUGH OVER THE NORTHWESTERN GREAT
LAKES WILL DIVE SOUTH OVER LAKE MICHIGAN TONIGHT AS THE SURFACE LOW
TRACKS FROM THE SOO TO CENTRAL LAKE HURON. THIS WILL DRAG A SURFACE
COLD FRONT THROUGH THE MIDDLE OF THE CWA LATE TONIGHT...BRINGING A
RENEWED CHANCE FOR RAIN TO THE AREA. THE REAL COLD AIR WITH THIS
FRONT WILL HOLD OFF A BIT...WITH ALL LIQUID PRECIPITATION EXPECTED
THROUGH THE OVERNIGHT HOURS AS SOUNDINGS SHOW A FAIRLY WARM BOUNDARY
LAYER THROUGH 12Z FRIDAY. THEREFORE WILL KEEP OUT MENTION OF SNOW
MIXING IN WITH THE RAIN THROUGH THE OVERNIGHT HOURS. ALTHOUGH THE
SURFACE FRONT WILL MAKE IT OVER THE WESTERN CWA LATE TONIGHT...THE
MAIN MID AND UPPER LEVEL DYNAMICS WILL LAG BEHIND THE FRONT A
BIT...AS EVIDENCED BY THE ABUNDANT AMOUNT OF POST FRONTAL
PRECIPITATION. GIVEN THESE FACTORS WILL CONTINUE WITH THE HIGH
LIKELY POPS ACROSS THE WEST TONIGHT AND NOT RAISE POPS TO
CATEGORICAL WITH THIS ISSUANCE. THE ABUNDANT CLOUD COVER AND RAIN
SHOWERS WILL KEEP THE DIURNAL RANGE TO A MINIMUM WITH LOWS AROUND 40
DEGREES TONIGHT GIVEN THE LAG OF COLD AIR BEHIND THE SURFACE COLD
FRONT.

LONG TERM...

LATEST WATER VAPOR IMAGERY SHOWS CENTER OF UPPER LEVEL CIRCULATION/
PV ANOMALY OVER NORTHERN MANITOBA...ADVANCING SOUTHEAST.
UNFORTUNATELY...THE 00Z MODELS (GFS/NAM/CANADIAN/EURO) STILL ARE NOT
IN GOOD AGREEMENT WITH THE TRACK AND CLOSING OFF OF THE 500 MB LOW.
NAM/GFS ARE CLOSING THE 500 MB OFF FASTER AND ARE FARTHER
EAST...OVER WESTERN HALF OF LOWER MICHIGAN...WHILE EURO REMAINS OPEN
A BIT LONGER AND IS MUCH FARTHER WEST...WITH THE CANADIAN BEING THE
FARTHER EAST...TRACKING IN BETWEEN THE CENTRAL/EASTERN GREAT LAKES.
REGARDLESS OF THE SOLUTION...A VERY TIGHT LOW LEVEL (925-850 MB)
BAROCLINIC ZONE OVER SOUTHEAST MICHIGAN SETTING UP...WITH THE
INCREASING NORTHEAST FLOW OFF THE WARM WATERS (LOWER 50S) OF LAKE
HURON FURTHERING STRENGTHENING OR AT THE VERY LEAST MAINTAINING
FRONTAL ZONE INTO FRIDAY NIGHT. SKEWING THE FORECAST A BIT TOWARD
THE NAM...WHICH HOPEFULLY CAN FACTOR IN THE MESOSCALE INFLUENCE OF
LAKE HURON A BIT BETTER...IT CONTINUES TO LOOK LIKE PREDOMINATELY
RAIN/NON-ACCUMULATING WET SNOW THROUGH THE DAY ON FRIDAY...AS NAM
MAINTAINS SURFACE DEW PTS COMFORTABLY ABOVE FREEZING THROUGH
21Z...WITH SIGNIFICANT DRYING THEN ATTEMPTING TO MAKE INROADS TOWARD
THE U.S. 23 CORRIDOR. EXPECTING PRECIPITATION TO CONTINUE EAST OF
U.S. 23 THROUGH FRIDAY NIGHT AS 850-700 MB MOISTURE/THETA-E RIDGE
SEEN ARCHING BACK FRIDAY EVENING WITH CONTINUED LAKE HURON
ENHANCEMENT TAKING PLACE BASED ON 850 MB TEMPS OF -5 TO -10 C. THE
STRONG INFLUENCE/FLOW OFF LAKE HURON LOOKS TO BE THE OVERRIDING
FACTOR IN THE EQUATION KEEPING SURFACE/NEAR SURFACE LAYER JUST WARM
ENOUGH TO PREVENT MUCH IN THE WAY OF SNOW ACCUMULATION AS BOTH
GFS/NAM INDICATING 925 MB TEMPS REMAINING ABOVE -3 C EAST OF U.S
23...WITH SURFACE DEW PTS STILL HOVERING AT OR ABOVE FREEZING. ALONG
AND WEST OF U.S. 23...DRY AIR WILL PROBABLY WIN OUT...ESPECIALLY IF
ONE IS TO BELIEVE THE EURO...BUT IF ANY PRECIPITATION DOES MAKE IT
THIS FAR WEST...LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE.

NORTHERLY WINDS WILL BE STRONG FRIDAY AFTERNOON/EVENING...BUT THERE
IS LITTLE IN THE WAY OF DOWNWARD MOMENTUM (PREDOMINATELY CONTINUED
POSITIVE LOW LEVEL ASCENT)...AND PRECIPITATION DRAG ISSUES TO
CONTEND WITH. RISE/FALL COUPLET WORKING THROUGH IS ALSO NOTHING
SPECIAL 10-12 MB...AND THUS EXPECTING GUSTS TO TOP OUT IN THE 35 TO
40 MPH RANGE...THE EXCEPTION WOULD BE RIGHT NEAR THE LAKE HURON
LAKESHORE WHERE HIGHER GUSTS ARE POSSIBLE.

AMPLIFIED UPPER LEVEL RIDGE WILL GRADUALLY BUILD INTO THE GREAT
LAKES REGION OVER THE WEEKEND....SHUTTING OFF THE LAKE EFFECT AND
ALLOWING TEMPERATURES TO ATTEMPT TO MODERATE. THE PROBLEM IS SURFACE
HIGH BUILD IN WILL ALLOW FOR SURFACE TEMPERATURES TO CRATER (20S)
SATURDAY NIGHT AS SKIES ARE EXPECTED TO BE MOSTLY CLEAR...AND
BOUNDARY LAYER MIXING ON SUNDAY WILL BE LIMITED...AS SUN
ANGLE/OVERALL INSOLATION DECLINES AS WE HEAD INTO NOVEMBER. 925 MB
FORECASTED (EURO)TEMPS TO CLIMB TO SLIGHTLY POSITIVE...SUPPORTIVE OF
MID 40S FOR HIGHS.

MARINE...
A RIDGE OF HIGH PRESSURE WILL MAINTAIN FAIRLY LIGHT WINDS AND LOW
WAVES TODAY. A STRONG LOW PRESSURE SYSTEM AND ARCTIC FRONT REMAINS
ON TRACK TO SWING INTO THE CENTRAL GREAT LAKES LATE TONIGHT.
NORTHERLY WINDS WILL BECOME STRONG BEHIND THE FRONT
FRIDAY AND FRIDAY NIGHT...WITH GUSTS LIKELY REACHING GALE FORCE OVER
MUCH OF LAKE HURON. THE STRONG PERSISTENT NORTHERLY WINDS
WILL ALLOW WAVE HEIGHTS TO BUILD IN EXCESS OF 10 FEET OVER
SOUTHERN LAKE HURON. WINDS WILL GRADUALLY DIMINISH ON SATURDAY AS
THE LOW MOVES EAST AND HIGH PRESSURE BUILDS INTO THE
AREA. HOWEVER...THE WAVES WILL BE SLOWER TO DECREASE...AND WILL
LIKELY NOT DROP BELOW 4 FEET UNTIL SATURDAY NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-421-422-441-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ442-443-463-464.

     GALE WATCH FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON FOR LHZ361.

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

$$

AVIATION.....DT
SHORT TERM...KURIMSKI
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 301054
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
654 AM EDT THU OCT 30 2014


.AVIATION...

//DISCUSSION...

AN AREA OF MVFR STRATOCU FROM THE THUMB HAS MOVED OVER THE METRO
AIRPORTS EARLY THIS MORNING...AS LAKE MOISTURE FROM LAKE MICHIGAN
HAS MOVED OVER MBS AND FNT AT TIMES. THE MVFR CLOUDS SHOULD
DISSIPATE THIS MORNING OVER THE METRO AIRPORTS AS WINDS TURN
WESTERLY AND PUSH THE CLOUDS OFF TO THE EAST. CLOUDS FROM LAKE
MICHIGAN WILL THEN MAKE AN EASTWARD MOVE...BUT THESE ARE EXPECTED TO
REMAIN LOW END VFR THROUGH THE MORNING. VFR CEILING WILL INCREASE
COVERAGE DURING THE AFTERNOON BEFORE LIGHT RAIN BECOMES POSSIBLE
THIS EVENING AND CONTINUING INTO THE OVERNIGHT HOURS.

//DTW THRESHOLD THREATS...

* MODERATE CONFIDENCE IN CEILING BELOW 5000 FT THROUGH THIS
  EVENING...HIGH CONFIDENCE OVERNIGHT.

&&

.PREV DISCUSSION...ISSUED 335 AM EDT THU OCT 30 2014

SHORT TERM...TODAY AND TONIGHT

SHORTWAVE RIDGING WILL TRACK EAST THROUGH THE CENTRAL GREAT LAKES
THIS MORNING...KEEPING WINDS CALM AND CONDITIONS RELATIVELY DRY
DURING THE DAYTIME HOURS. DESPITE MORNING SUNSHINE...CLOUDS WILL
INCREASE THROUGH THE DAY AS MOISTURE ADVECTS IN FROM THE WEST AHEAD
OF A DEVELOPING LOW PRESSURE SYSTEM DIVING SOUTH FROM CANADA TOWARDS
THE NORTHWESTERN GREAT LAKES THIS AFTERNOON. GIVEN THE MID AND UPPER
LEVEL WAVE WILL STILL BE FAR TO THE NORTHWEST...RAIN WITH THIS
SYSTEM IS NOT EXPECTED TO AFFECT THE AREA TODAY. WITH COLD AIR STILL
IN PLACE AND INCREASING CLOUDS...HIGHS WILL GENERALLY BE AROUND 50
DEGREES...WITH SOME MID 40S POSSIBLE OVER THE NORTHERN THUMB REGION.

THE POSITIVELY TILTED MID LEVEL TROUGH OVER THE NORTHWESTERN GREAT
LAKES WILL DIVE SOUTH OVER LAKE MICHIGAN TONIGHT AS THE SURFACE LOW
TRACKS FROM THE SOO TO CENTRAL LAKE HURON. THIS WILL DRAG A SURFACE
COLD FRONT THROUGH THE MIDDLE OF THE CWA LATE TONIGHT...BRINGING A
RENEWED CHANCE FOR RAIN TO THE AREA. THE REAL COLD AIR WITH THIS
FRONT WILL HOLD OFF A BIT...WITH ALL LIQUID PRECIPITATION EXPECTED
THROUGH THE OVERNIGHT HOURS AS SOUNDINGS SHOW A FAIRLY WARM BOUNDARY
LAYER THROUGH 12Z FRIDAY. THEREFORE WILL KEEP OUT MENTION OF SNOW
MIXING IN WITH THE RAIN THROUGH THE OVERNIGHT HOURS. ALTHOUGH THE
SURFACE FRONT WILL MAKE IT OVER THE WESTERN CWA LATE TONIGHT...THE
MAIN MID AND UPPER LEVEL DYNAMICS WILL LAG BEHIND THE FRONT A
BIT...AS EVIDENCED BY THE ABUNDANT AMOUNT OF POST FRONTAL
PRECIPITATION. GIVEN THESE FACTORS WILL CONTINUE WITH THE HIGH
LIKELY POPS ACROSS THE WEST TONIGHT AND NOT RAISE POPS TO
CATEGORICAL WITH THIS ISSUANCE. THE ABUNDANT CLOUD COVER AND RAIN
SHOWERS WILL KEEP THE DIURNAL RANGE TO A MINIMUM WITH LOWS AROUND 40
DEGREES TONIGHT GIVEN THE LAG OF COLD AIR BEHIND THE SURFACE COLD
FRONT.

LONG TERM...

LATEST WATER VAPOR IMAGERY SHOWS CENTER OF UPPER LEVEL CIRCULATION/
PV ANOMALY OVER NORTHERN MANITOBA...ADVANCING SOUTHEAST.
UNFORTUNATELY...THE 00Z MODELS (GFS/NAM/CANADIAN/EURO) STILL ARE NOT
IN GOOD AGREEMENT WITH THE TRACK AND CLOSING OFF OF THE 500 MB LOW.
NAM/GFS ARE CLOSING THE 500 MB OFF FASTER AND ARE FARTHER
EAST...OVER WESTERN HALF OF LOWER MICHIGAN...WHILE EURO REMAINS OPEN
A BIT LONGER AND IS MUCH FARTHER WEST...WITH THE CANADIAN BEING THE
FARTHER EAST...TRACKING IN BETWEEN THE CENTRAL/EASTERN GREAT LAKES.
REGARDLESS OF THE SOLUTION...A VERY TIGHT LOW LEVEL (925-850 MB)
BAROCLINIC ZONE OVER SOUTHEAST MICHIGAN SETTING UP...WITH THE
INCREASING NORTHEAST FLOW OFF THE WARM WATERS (LOWER 50S) OF LAKE
HURON FURTHERING STRENGTHENING OR AT THE VERY LEAST MAINTAINING
FRONTAL ZONE INTO FRIDAY NIGHT. SKEWING THE FORECAST A BIT TOWARD
THE NAM...WHICH HOPEFULLY CAN FACTOR IN THE MESOSCALE INFLUENCE OF
LAKE HURON A BIT BETTER...IT CONTINUES TO LOOK LIKE PREDOMINATELY
RAIN/NON-ACCUMULATING WET SNOW THROUGH THE DAY ON FRIDAY...AS NAM
MAINTAINS SURFACE DEW PTS COMFORTABLY ABOVE FREEZING THROUGH
21Z...WITH SIGNIFICANT DRYING THEN ATTEMPTING TO MAKE INROADS TOWARD
THE U.S. 23 CORRIDOR. EXPECTING PRECIPITATION TO CONTINUE EAST OF
U.S. 23 THROUGH FRIDAY NIGHT AS 850-700 MB MOISTURE/THETA-E RIDGE
SEEN ARCHING BACK FRIDAY EVENING WITH CONTINUED LAKE HURON
ENHANCEMENT TAKING PLACE BASED ON 850 MB TEMPS OF -5 TO -10 C. THE
STRONG INFLUENCE/FLOW OFF LAKE HURON LOOKS TO BE THE OVERRIDING
FACTOR IN THE EQUATION KEEPING SURFACE/NEAR SURFACE LAYER JUST WARM
ENOUGH TO PREVENT MUCH IN THE WAY OF SNOW ACCUMULATION AS BOTH
GFS/NAM INDICATING 925 MB TEMPS REMAINING ABOVE -3 C EAST OF U.S
23...WITH SURFACE DEW PTS STILL HOVERING AT OR ABOVE FREEZING. ALONG
AND WEST OF U.S. 23...DRY AIR WILL PROBABLY WIN OUT...ESPECIALLY IF
ONE IS TO BELIEVE THE EURO...BUT IF ANY PRECIPITATION DOES MAKE IT
THIS FAR WEST...LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE.

NORTHERLY WINDS WILL BE STRONG FRIDAY AFTERNOON/EVENING...BUT THERE
IS LITTLE IN THE WAY OF DOWNWARD MOMENTUM (PREDOMINATELY CONTINUED
POSITIVE LOW LEVEL ASCENT)...AND PRECIPITATION DRAG ISSUES TO
CONTEND WITH. RISE/FALL COUPLET WORKING THROUGH IS ALSO NOTHING
SPECIAL 10-12 MB...AND THUS EXPECTING GUSTS TO TOP OUT IN THE 35 TO
40 MPH RANGE...THE EXCEPTION WOULD BE RIGHT NEAR THE LAKE HURON
LAKESHORE WHERE HIGHER GUSTS ARE POSSIBLE.

AMPLIFIED UPPER LEVEL RIDGE WILL GRADUALLY BUILD INTO THE GREAT
LAKES REGION OVER THE WEEKEND....SHUTTING OFF THE LAKE EFFECT AND
ALLOWING TEMPERATURES TO ATTEMPT TO MODERATE. THE PROBLEM IS SURFACE
HIGH BUILD IN WILL ALLOW FOR SURFACE TEMPERATURES TO CRATER (20S)
SATURDAY NIGHT AS SKIES ARE EXPECTED TO BE MOSTLY CLEAR...AND
BOUNDARY LAYER MIXING ON SUNDAY WILL BE LIMITED...AS SUN
ANGLE/OVERALL INSOLATION DECLINES AS WE HEAD INTO NOVEMBER. 925 MB
FORECASTED (EURO)TEMPS TO CLIMB TO SLIGHTLY POSITIVE...SUPPORTIVE OF
MID 40S FOR HIGHS.

MARINE...
A RIDGE OF HIGH PRESSURE WILL MAINTAIN FAIRLY LIGHT WINDS AND LOW
WAVES TODAY. A STRONG LOW PRESSURE SYSTEM AND ARCTIC FRONT REMAINS
ON TRACK TO SWING INTO THE CENTRAL GREAT LAKES LATE TONIGHT.
NORTHERLY WINDS WILL BECOME STRONG BEHIND THE FRONT
FRIDAY AND FRIDAY NIGHT...WITH GUSTS LIKELY REACHING GALE FORCE OVER
MUCH OF LAKE HURON. THE STRONG PERSISTENT NORTHERLY WINDS
WILL ALLOW WAVE HEIGHTS TO BUILD IN EXCESS OF 10 FEET OVER
SOUTHERN LAKE HURON. WINDS WILL GRADUALLY DIMINISH ON SATURDAY AS
THE LOW MOVES EAST AND HIGH PRESSURE BUILDS INTO THE
AREA. HOWEVER...THE WAVES WILL BE SLOWER TO DECREASE...AND WILL
LIKELY NOT DROP BELOW 4 FEET UNTIL SATURDAY NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-421-422-441-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ442-443-463-464.

     GALE WATCH FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON FOR LHZ361.

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

$$

AVIATION.....KURIMSKI
SHORT TERM...KURIMSKI
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 301054
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
654 AM EDT THU OCT 30 2014


.AVIATION...

//DISCUSSION...

AN AREA OF MVFR STRATOCU FROM THE THUMB HAS MOVED OVER THE METRO
AIRPORTS EARLY THIS MORNING...AS LAKE MOISTURE FROM LAKE MICHIGAN
HAS MOVED OVER MBS AND FNT AT TIMES. THE MVFR CLOUDS SHOULD
DISSIPATE THIS MORNING OVER THE METRO AIRPORTS AS WINDS TURN
WESTERLY AND PUSH THE CLOUDS OFF TO THE EAST. CLOUDS FROM LAKE
MICHIGAN WILL THEN MAKE AN EASTWARD MOVE...BUT THESE ARE EXPECTED TO
REMAIN LOW END VFR THROUGH THE MORNING. VFR CEILING WILL INCREASE
COVERAGE DURING THE AFTERNOON BEFORE LIGHT RAIN BECOMES POSSIBLE
THIS EVENING AND CONTINUING INTO THE OVERNIGHT HOURS.

//DTW THRESHOLD THREATS...

* MODERATE CONFIDENCE IN CEILING BELOW 5000 FT THROUGH THIS
  EVENING...HIGH CONFIDENCE OVERNIGHT.

&&

.PREV DISCUSSION...ISSUED 335 AM EDT THU OCT 30 2014

SHORT TERM...TODAY AND TONIGHT

SHORTWAVE RIDGING WILL TRACK EAST THROUGH THE CENTRAL GREAT LAKES
THIS MORNING...KEEPING WINDS CALM AND CONDITIONS RELATIVELY DRY
DURING THE DAYTIME HOURS. DESPITE MORNING SUNSHINE...CLOUDS WILL
INCREASE THROUGH THE DAY AS MOISTURE ADVECTS IN FROM THE WEST AHEAD
OF A DEVELOPING LOW PRESSURE SYSTEM DIVING SOUTH FROM CANADA TOWARDS
THE NORTHWESTERN GREAT LAKES THIS AFTERNOON. GIVEN THE MID AND UPPER
LEVEL WAVE WILL STILL BE FAR TO THE NORTHWEST...RAIN WITH THIS
SYSTEM IS NOT EXPECTED TO AFFECT THE AREA TODAY. WITH COLD AIR STILL
IN PLACE AND INCREASING CLOUDS...HIGHS WILL GENERALLY BE AROUND 50
DEGREES...WITH SOME MID 40S POSSIBLE OVER THE NORTHERN THUMB REGION.

THE POSITIVELY TILTED MID LEVEL TROUGH OVER THE NORTHWESTERN GREAT
LAKES WILL DIVE SOUTH OVER LAKE MICHIGAN TONIGHT AS THE SURFACE LOW
TRACKS FROM THE SOO TO CENTRAL LAKE HURON. THIS WILL DRAG A SURFACE
COLD FRONT THROUGH THE MIDDLE OF THE CWA LATE TONIGHT...BRINGING A
RENEWED CHANCE FOR RAIN TO THE AREA. THE REAL COLD AIR WITH THIS
FRONT WILL HOLD OFF A BIT...WITH ALL LIQUID PRECIPITATION EXPECTED
THROUGH THE OVERNIGHT HOURS AS SOUNDINGS SHOW A FAIRLY WARM BOUNDARY
LAYER THROUGH 12Z FRIDAY. THEREFORE WILL KEEP OUT MENTION OF SNOW
MIXING IN WITH THE RAIN THROUGH THE OVERNIGHT HOURS. ALTHOUGH THE
SURFACE FRONT WILL MAKE IT OVER THE WESTERN CWA LATE TONIGHT...THE
MAIN MID AND UPPER LEVEL DYNAMICS WILL LAG BEHIND THE FRONT A
BIT...AS EVIDENCED BY THE ABUNDANT AMOUNT OF POST FRONTAL
PRECIPITATION. GIVEN THESE FACTORS WILL CONTINUE WITH THE HIGH
LIKELY POPS ACROSS THE WEST TONIGHT AND NOT RAISE POPS TO
CATEGORICAL WITH THIS ISSUANCE. THE ABUNDANT CLOUD COVER AND RAIN
SHOWERS WILL KEEP THE DIURNAL RANGE TO A MINIMUM WITH LOWS AROUND 40
DEGREES TONIGHT GIVEN THE LAG OF COLD AIR BEHIND THE SURFACE COLD
FRONT.

LONG TERM...

LATEST WATER VAPOR IMAGERY SHOWS CENTER OF UPPER LEVEL CIRCULATION/
PV ANOMALY OVER NORTHERN MANITOBA...ADVANCING SOUTHEAST.
UNFORTUNATELY...THE 00Z MODELS (GFS/NAM/CANADIAN/EURO) STILL ARE NOT
IN GOOD AGREEMENT WITH THE TRACK AND CLOSING OFF OF THE 500 MB LOW.
NAM/GFS ARE CLOSING THE 500 MB OFF FASTER AND ARE FARTHER
EAST...OVER WESTERN HALF OF LOWER MICHIGAN...WHILE EURO REMAINS OPEN
A BIT LONGER AND IS MUCH FARTHER WEST...WITH THE CANADIAN BEING THE
FARTHER EAST...TRACKING IN BETWEEN THE CENTRAL/EASTERN GREAT LAKES.
REGARDLESS OF THE SOLUTION...A VERY TIGHT LOW LEVEL (925-850 MB)
BAROCLINIC ZONE OVER SOUTHEAST MICHIGAN SETTING UP...WITH THE
INCREASING NORTHEAST FLOW OFF THE WARM WATERS (LOWER 50S) OF LAKE
HURON FURTHERING STRENGTHENING OR AT THE VERY LEAST MAINTAINING
FRONTAL ZONE INTO FRIDAY NIGHT. SKEWING THE FORECAST A BIT TOWARD
THE NAM...WHICH HOPEFULLY CAN FACTOR IN THE MESOSCALE INFLUENCE OF
LAKE HURON A BIT BETTER...IT CONTINUES TO LOOK LIKE PREDOMINATELY
RAIN/NON-ACCUMULATING WET SNOW THROUGH THE DAY ON FRIDAY...AS NAM
MAINTAINS SURFACE DEW PTS COMFORTABLY ABOVE FREEZING THROUGH
21Z...WITH SIGNIFICANT DRYING THEN ATTEMPTING TO MAKE INROADS TOWARD
THE U.S. 23 CORRIDOR. EXPECTING PRECIPITATION TO CONTINUE EAST OF
U.S. 23 THROUGH FRIDAY NIGHT AS 850-700 MB MOISTURE/THETA-E RIDGE
SEEN ARCHING BACK FRIDAY EVENING WITH CONTINUED LAKE HURON
ENHANCEMENT TAKING PLACE BASED ON 850 MB TEMPS OF -5 TO -10 C. THE
STRONG INFLUENCE/FLOW OFF LAKE HURON LOOKS TO BE THE OVERRIDING
FACTOR IN THE EQUATION KEEPING SURFACE/NEAR SURFACE LAYER JUST WARM
ENOUGH TO PREVENT MUCH IN THE WAY OF SNOW ACCUMULATION AS BOTH
GFS/NAM INDICATING 925 MB TEMPS REMAINING ABOVE -3 C EAST OF U.S
23...WITH SURFACE DEW PTS STILL HOVERING AT OR ABOVE FREEZING. ALONG
AND WEST OF U.S. 23...DRY AIR WILL PROBABLY WIN OUT...ESPECIALLY IF
ONE IS TO BELIEVE THE EURO...BUT IF ANY PRECIPITATION DOES MAKE IT
THIS FAR WEST...LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE.

NORTHERLY WINDS WILL BE STRONG FRIDAY AFTERNOON/EVENING...BUT THERE
IS LITTLE IN THE WAY OF DOWNWARD MOMENTUM (PREDOMINATELY CONTINUED
POSITIVE LOW LEVEL ASCENT)...AND PRECIPITATION DRAG ISSUES TO
CONTEND WITH. RISE/FALL COUPLET WORKING THROUGH IS ALSO NOTHING
SPECIAL 10-12 MB...AND THUS EXPECTING GUSTS TO TOP OUT IN THE 35 TO
40 MPH RANGE...THE EXCEPTION WOULD BE RIGHT NEAR THE LAKE HURON
LAKESHORE WHERE HIGHER GUSTS ARE POSSIBLE.

AMPLIFIED UPPER LEVEL RIDGE WILL GRADUALLY BUILD INTO THE GREAT
LAKES REGION OVER THE WEEKEND....SHUTTING OFF THE LAKE EFFECT AND
ALLOWING TEMPERATURES TO ATTEMPT TO MODERATE. THE PROBLEM IS SURFACE
HIGH BUILD IN WILL ALLOW FOR SURFACE TEMPERATURES TO CRATER (20S)
SATURDAY NIGHT AS SKIES ARE EXPECTED TO BE MOSTLY CLEAR...AND
BOUNDARY LAYER MIXING ON SUNDAY WILL BE LIMITED...AS SUN
ANGLE/OVERALL INSOLATION DECLINES AS WE HEAD INTO NOVEMBER. 925 MB
FORECASTED (EURO)TEMPS TO CLIMB TO SLIGHTLY POSITIVE...SUPPORTIVE OF
MID 40S FOR HIGHS.

MARINE...
A RIDGE OF HIGH PRESSURE WILL MAINTAIN FAIRLY LIGHT WINDS AND LOW
WAVES TODAY. A STRONG LOW PRESSURE SYSTEM AND ARCTIC FRONT REMAINS
ON TRACK TO SWING INTO THE CENTRAL GREAT LAKES LATE TONIGHT.
NORTHERLY WINDS WILL BECOME STRONG BEHIND THE FRONT
FRIDAY AND FRIDAY NIGHT...WITH GUSTS LIKELY REACHING GALE FORCE OVER
MUCH OF LAKE HURON. THE STRONG PERSISTENT NORTHERLY WINDS
WILL ALLOW WAVE HEIGHTS TO BUILD IN EXCESS OF 10 FEET OVER
SOUTHERN LAKE HURON. WINDS WILL GRADUALLY DIMINISH ON SATURDAY AS
THE LOW MOVES EAST AND HIGH PRESSURE BUILDS INTO THE
AREA. HOWEVER...THE WAVES WILL BE SLOWER TO DECREASE...AND WILL
LIKELY NOT DROP BELOW 4 FEET UNTIL SATURDAY NIGHT.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-421-422-441-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ442-443-463-464.

     GALE WATCH FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON FOR LHZ361.

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

$$

AVIATION.....KURIMSKI
SHORT TERM...KURIMSKI
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 THU OCT 30 2014

.SHORT TERM...TODAY AND TONIGHT

SHORTWAVE RIDGING WILL TRACK EAST THROUGH THE CENTRAL GREAT LAKES
THIS MORNING...KEEPING WINDS CALM AND CONDITIONS RELATIVELY DRY
DURING THE DAYTIME HOURS. DESPITE MORNING SUNSHINE...CLOUDS WILL
INCREASE THROUGH THE DAY AS MOISTURE ADVECTS IN FROM THE WEST AHEAD
OF A DEVELOPING LOW PRESSURE SYSTEM DIVING SOUTH FROM CANADA TOWARDS
THE NORTHWESTERN GREAT LAKES THIS AFTERNOON. GIVEN THE MID AND UPPER
LEVEL WAVE WILL STILL BE FAR TO THE NORTHWEST...RAIN WITH THIS
SYSTEM IS NOT EXPECTED TO AFFECT THE AREA TODAY. WITH COLD AIR STILL
IN PLACE AND INCREASING CLOUDS...HIGHS WILL GENERALLY BE AROUND 50
DEGREES...WITH SOME MID 40S POSSIBLE OVER THE NORTHERN THUMB REGION.

THE POSITIVELY TILTED MID LEVEL TROUGH OVER THE NORTHWESTERN GREAT
LAKES WILL DIVE SOUTH OVER LAKE MICHIGAN TONIGHT AS THE SURFACE LOW
TRACKS FROM THE SOO TO CENTRAL LAKE HURON. THIS WILL DRAG A SURFACE
COLD FRONT THROUGH THE MIDDLE OF THE CWA LATE TONIGHT...BRINGING A
RENEWED CHANCE FOR RAIN TO THE AREA. THE REAL COLD AIR WITH THIS
FRONT WILL HOLD OFF A BIT...WITH ALL LIQUID PRECIPITATION EXPECTED
THROUGH THE OVERNIGHT HOURS AS SOUNDINGS SHOW A FAIRLY WARM BOUNDARY
LAYER THROUGH 12Z FRIDAY. THEREFORE WILL KEEP OUT MENTION OF SNOW
MIXING IN WITH THE RAIN THROUGH THE OVERNIGHT HOURS. ALTHOUGH THE
SURFACE FRONT WILL MAKE IT OVER THE WESTERN CWA LATE TONIGHT...THE
MAIN MID AND UPPER LEVEL DYNAMICS WILL LAG BEHIND THE FRONT A
BIT...AS EVIDENCED BY THE ABUNDANT AMOUNT OF POST FRONTAL
PRECIPITATION. GIVEN THESE FACTORS WILL CONTINUE WITH THE HIGH
LIKELY POPS ACROSS THE WEST TONIGHT AND NOT RAISE POPS TO
CATEGORICAL WITH THIS ISSUANCE. THE ABUNDANT CLOUD COVER AND RAIN
SHOWERS WILL KEEP THE DIURNAL RANGE TO A MINIMUM WITH LOWS AROUND 40
DEGREES TONIGHT GIVEN THE LAG OF COLD AIR BEHIND THE SURFACE COLD
FRONT.

&&

.LONG TERM...

LATEST WATER VAPOR IMAGERY SHOWS CENTER OF UPPER LEVEL CIRCULATION/
PV ANOMALY OVER NORTHERN MANITOBA...ADVANCING SOUTHEAST.
UNFORTUNATELY...THE 00Z MODELS (GFS/NAM/CANADIAN/EURO) STILL ARE NOT
IN GOOD AGREEMENT WITH THE TRACK AND CLOSING OFF OF THE 500 MB LOW.
NAM/GFS ARE CLOSING THE 500 MB OFF FASTER AND ARE FARTHER
EAST...OVER WESTERN HALF OF LOWER MICHIGAN...WHILE EURO REMAINS OPEN
A BIT LONGER AND IS MUCH FARTHER WEST...WITH THE CANADIAN BEING THE
FARTHER EAST...TRACKING IN BETWEEN THE CENTRAL/EASTERN GREAT LAKES.
REGARDLESS OF THE SOLUTION...A VERY TIGHT LOW LEVEL (925-850 MB)
BAROCLINIC ZONE OVER SOUTHEAST MICHIGAN SETTING UP...WITH THE
INCREASING NORTHEAST FLOW OFF THE WARM WATERS (LOWER 50S) OF LAKE
HURON FURTHERING STRENGTHENING OR AT THE VERY LEAST MAINTAINING
FRONTAL ZONE INTO FRIDAY NIGHT. SKEWING THE FORECAST A BIT TOWARD
THE NAM...WHICH HOPEFULLY CAN FACTOR IN THE MESOSCALE INFLUENCE OF
LAKE HURON A BIT BETTER...IT CONTINUES TO LOOK LIKE PREDOMINATELY
RAIN/NON-ACCUMULATING WET SNOW THROUGH THE DAY ON FRIDAY...AS NAM
MAINTAINS SURFACE DEW PTS COMFORTABLY ABOVE FREEZING THROUGH
21Z...WITH SIGNIFICANT DRYING THEN ATTEMPTING TO MAKE INROADS TOWARD
THE U.S. 23 CORRIDOR. EXPECTING PRECIPITATION TO CONTINUE EAST OF
U.S. 23 THROUGH FRIDAY NIGHT AS 850-700 MB MOISTURE/THETA-E RIDGE
SEEN ARCHING BACK FRIDAY EVENING WITH CONTINUED LAKE HURON
ENHANCEMENT TAKING PLACE BASED ON 850 MB TEMPS OF -5 TO -10 C. THE
STRONG INFLUENCE/FLOW OFF LAKE HURON LOOKS TO BE THE OVERRIDING
FACTOR IN THE EQUATION KEEPING SURFACE/NEAR SURFACE LAYER JUST WARM
ENOUGH TO PREVENT MUCH IN THE WAY OF SNOW ACCUMULATION AS BOTH
GFS/NAM INDICATING 925 MB TEMPS REMAINING ABOVE -3 C EAST OF U.S
23...WITH SURFACE DEW PTS STILL HOVERING AT OR ABOVE FREEZING. ALONG
AND WEST OF U.S. 23...DRY AIR WILL PROBABLY WIN OUT...ESPECIALLY IF
ONE IS TO BELIEVE THE EURO...BUT IF ANY PRECIPITATION DOES MAKE IT
THIS FAR WEST...LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE.

NORTHERLY WINDS WILL BE STRONG FRIDAY AFTERNOON/EVENING...BUT THERE
IS LITTLE IN THE WAY OF DOWNWARD MOMENTUM (PREDOMINATELY CONTINUED
POSITIVE LOW LEVEL ASCENT)...AND PRECIPITATION DRAG ISSUES TO
CONTEND WITH. RISE/FALL COUPLET WORKING THROUGH IS ALSO NOTHING
SPECIAL 10-12 MB...AND THUS EXPECTING GUSTS TO TOP OUT IN THE 35 TO
40 MPH RANGE...THE EXCEPTION WOULD BE RIGHT NEAR THE LAKE HURON
LAKESHORE WHERE HIGHER GUSTS ARE POSSIBLE.

AMPLIFIED UPPER LEVEL RIDGE WILL GRADUALLY BUILD INTO THE GREAT
LAKES REGION OVER THE WEEKEND....SHUTTING OFF THE LAKE EFFECT AND
ALLOWING TEMPERATURES TO ATTEMPT TO MODERATE. THE PROBLEM IS SURFACE
HIGH BUILD IN WILL ALLOW FOR SURFACE TEMPERATURES TO CRATER (20S)
SATURDAY NIGHT AS SKIES ARE EXPECTED TO BE MOSTLY CLEAR...AND
BOUNDARY LAYER MIXING ON SUNDAY WILL BE LIMITED...AS SUN
ANGLE/OVERALL INSOLATION DECLINES AS WE HEAD INTO NOVEMBER. 925 MB
FORECASTED (EURO)TEMPS TO CLIMB TO SLIGHTLY POSITIVE...SUPPORTIVE OF
MID 40S FOR HIGHS.

&&

.MARINE...
A RIDGE OF HIGH PRESSURE WILL MAINTAIN FAIRLY LIGHT WINDS AND LOW
WAVES TODAY. A STRONG LOW PRESSURE SYSTEM AND ARCTIC FRONT REMAINS
ON TRACK TO SWING INTO THE CENTRAL GREAT LAKES LATE TONIGHT.
NORTHERLY WINDS WILL BECOME STRONG BEHIND THE FRONT
FRIDAY AND FRIDAY NIGHT...WITH GUSTS LIKELY REACHING GALE FORCE OVER
MUCH OF LAKE HURON. THE STRONG PERSISTENT NORTHERLY WINDS
WILL ALLOW WAVE HEIGHTS TO BUILD IN EXCESS OF 10 FEET OVER
SOUTHERN LAKE HURON. WINDS WILL GRADUALLY DIMINISH ON SATURDAY AS
THE LOW MOVES EAST AND HIGH PRESSURE BUILDS INTO THE
AREA. HOWEVER...THE WAVES WILL BE SLOWER TO DECREASE...AND WILL
LIKELY NOT DROP BELOW 4 FEET UNTIL SATURDAY NIGHT.

&&

.AVIATION...ISSUED 1205 AM EDT THU OCT 30 2014

//DISCUSSION...

LATE EVENING OBSERVATIONS INDICATE SOME PATCHES OF MVFR STRATOCU
OVER NORTHERN LOWER THAT HAVE THE BEST CHANCE OF AFFECTING MBS AND
FNT DURING THE REST OF THE NIGHT. IT WILL BE DIFFICULT FOR THESE
CLOUDS TO DEVELOP TOWARD DTW BEFORE THE LOW LEVEL WIND BEGINS
BACKING TOWARD THE WEST. CLOUDS FROM LAKE MICHIGAN WILL THEN MAKE AN
EASTWARD MOVE...BUT THESE ARE EXPECTED TO REMAIN LOW END VFR THROUGH
THE MORNING. VFR CEILING WILL INCREASE COVERAGE DURING THE AFTERNOON
BEFORE LIGHT RAIN BECOMES POSSIBLE THURSDAY EVENING.

//DTW THRESHOLD THREATS...

* MODERATE CONFIDENCE IN CEILING BELOW 5000 FT PREVAILING FROM
  AROUND SUNRISE THROUGH THURSDAY EVENING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-421-422-441-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ442-443-463-464.

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

$$

SHORT TERM...KURIMSKI
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 300405
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1205 AM EDT THU OCT 30 2014

.AVIATION...

//DISCUSSION...

LATE EVENING OBSERVATIONS INDICATE SOME PATCHES OF MVFR STRATOCU
OVER NORTHERN LOWER THAT HAVE THE BEST CHANCE OF AFFECTING MBS AND
FNT DURING THE REST OF THE NIGHT. IT WILL BE DIFFICULT FOR THESE
CLOUDS TO DEVELOP TOWARD DTW BEFORE THE LOW LEVEL WIND BEGINS
BACKING TOWARD THE WEST. CLOUDS FROM LAKE MICHIGAN WILL THEN MAKE AN
EASTWARD MOVE...BUT THESE ARE EXPECTED TO REMAIN LOW END VFR THROUGH
THE MORNING. VFR CEILING WILL INCREASE COVERAGE DURING THE AFTERNOON
BEFORE LIGHT RAIN BECOMES POSSIBLE THURSDAY EVENING.

//DTW THRESHOLD THREATS...

* MODERATE CONFIDENCE IN CEILING BELOW 5000 FT PREVAILING FROM
  AROUND SUNRISE THROUGH THURSDAY EVENING.

&&

.PREV DISCUSSION...ISSUED 403 PM EDT WED OCT 29 2014

SHORT TERM...TONIGHT

LINGERING RAIN SHOWERS AND GUSTY WINDS ACROSS SOUTHEAST MICHIGAN
WILL BOTH COME TO AN END SHORTLY AFTER SUNSET. BRIEF RIDGING
OVERNIGHT WILL ALLOW WINDS TO BECOME MOSTLY CALM AND CLOUD COVER TO
DIMINISH SLIGHTLY AS DRY AIR FILTERS INTO THE REGION. WHILE THE DRY
AIR WILL KEEP LOW LEVEL CLOUDS FROM DEVELOPING...ENOUGH MID LEVEL
MOISTURE WILL STICK AROUND TO KEEP SOME MID CLOUDS IN THE FORECAST
GIVING WAY TO A PARTLY CLOUDY FORECAST OVERNIGHT. LOW TEMPERATURES
WILL BE MUCH COOLER THAN PREVIOUS NIGHTS...WITH LOWS DROPPING DOWN
INTO THE LOW TO MID 30S ACROSS SOUTHEAST MICHIGAN. THE METRO DETROIT
AREA HAS THE POTENTIAL TO BE SLIGHTLY WARMER WITH TEMPERATURES ONLY
DROPPING INTO THE UPPER 30S.

LONG TERM...THURSDAY THROUGH NEXT WEDNESDAY

SURFACE RIDGING WILL PERSIST THROUGH MUCH OF THURSDAY BEFORE
SHIFTING EAST. ALTHOUGH QUIET CONDITIONS ARE EXPECTED UNDER THE
RIDGE TOMORROW...CLOUDS WILL INCREASE THROUGH THE DAY AS MOISTURE
ARRIVES AHEAD OF A LOW PRESSURE SYSTEM DROPPING THROUGH CANADA...AND
AS THE UPPER WAVE OVER THE NORTHERN ROCKIES DIVES INTO MO/IL.
OVERALL...EXPECTING A MOISTLY CLOUDY DAY FROM THE AFTERNOON GOING
FORWARD. TEMPERATURES WILL REMAIN UNSEASONABLY COOL IN THE WAKE OF A
WEAK FRONT THAT PUSHED THROUGH EARLIER TODAY...WITH MAX TEMPERATURES
FROM THE MID 40S TO LOW 50S.

MAIN FOCUS IN THE EXTENDED WILL BE THE NEXT SYSTEM DROPPING THROUGH
AS IT WILL BRING WINDY CONDITIONS...EVEN COLDER TEMPERATURES...AND
OUR FIRST CHANCE FOR LIGHT SNOWFALL THIS SEASON. SEVERAL PIECES OF
ENERGY FROM WAY UP OVER THE NORTHWEST TERRITORIES AND NUNAVUT WILL
CONSOLIDATE AS THEY DIVE THROUGH CANADA AND AND THE WESTERN GREAT
LAKES LATE THURSDAY THROUGH FRIDAY. SURFACE LOW PRESSURE SYSTEM AND
COLD FRONT WILL DROP THROUGH LOWER MICHIGAN FRIDAY...WITH GFS/NAM
MODELS NOW TRENDING TOWARDS THE TIMING OF THE EURO/GEM. THIS LOOKS
TO PUSH THE COLD FRONT THROUGH EARLY IN THE DAY...MAINLY BETWEEN 14Z
AND 20Z. FGEN FORCING AND STRONG PVA WILL WORK WITH A MODEST THETA-E
PLUME SURGING UP AHEAD OF THE SYSTEM TO GENERATE WIDESPREAD SHOWERS.
MAIN ISSUE WILL BE THE VERY COLD AIR COMING IN WITH THE ARCTIC FRONT
AND HOW SOON PRECIPITATION WILL CHANGE FROM RAIN TO SNOW. CHANGEOVER
WILL OCCUR FROM NORTHWEST TO SOUTHEAST THROUGH THE DAY (MAX TEMPS
WILL BE REACHED EARLIER IN THE DAY FOR ALL BUT THE DETROIT AREA)
.LOOKING TO START BY MID-MORNING NEAR THE SAGINAW VALLEY AND
FINALLY SWITCH OVER NEAR THE CITY OF DETROIT DURING THE EARLY
EVENING. EXPECTING MOSTLY SNOW BY 800 PM...WITH POTENTIALLY AN
EXCEPTION IMMEDIATELY ALONG THE SHORE OF LAKE HURON WHERE WINDS WILL
BE OFF THE WARMER WATER.

MOISTURE WILL START TO PULL AWAY AS THE LOW EXITS EAST
HOWEVER...KEEPING SNOW AMOUNTS FAIRLY LIGHT. WILL HAVE TO
CONTINUALLY REASSESS THIS WITH EACH RUN OF NEW MODEL DATA HOWEVER.
STILL SOME UNCERTAINTY AS TO HOW MUCH WILL ACTUALLY STICK ON THE
GROUND WITH WARM ROAD TEMPERATURES AND PAVEMENT. BEST CHANCE FOR
LIGHT ACCUMULATIONS (A FEW TENTHS LOOK BEST RIGHT NOW) WILL BE ON
ELEVATED AND GRASSY SURFACES. STRONG WINDS WILL ALSO ACCOMPANY THE
FRONT AS THE ARRIVAL OF COLDER AIR STEEPENS LAPSE RATES AND DEEPENS
THE BOUNDARY LAYER. FORECAST SOUNDINGS SUGGEST GUSTS TO 40 MPH...BUT
WILL NEED TO WATCH THE STRONGER EURO MODEL...WHICH HAS A CORE OF 40-
50 KNOTS AS LOW AS 925 MB. TEMPERATURES WILL BECOME QUITE CHILLY BY
FRIDAY EVENING...ESPECIALLY WHEN THE GUSTY WINDS ARE FACTORED IN.
EVENING WIND CHILLS LOOK TO RUN BETWEEN THE MID 20S TO LOW 30S. THIS
IS IN ADDITION TO LINGERING RAIN AND SNOW SHOWERS.

LAKE EFFECT RAIN/SNOW SHOWERS WILL BE POSSIBLE DURING THE EVENING
AND OVERNIGHT OFF LAKE HURON AFTER THE LOW PULLS AWAY...WITH STEEP
LAPSE RATES OVER THE WATER AND PERSISTENT NORTHERLY FLOW OFF THE
LAKE. THIS MAY BRING ADDITIONAL LIGHT ACCUMULATIONS.

THE WEEKEND REMAINS VERY COLD IN THE EXTENDED FORECAST. COLD AIR
ADVECTION DOES SLOW DOWN...BUT THE 0-1KM LAPSE RATES OVER LAKE HURON
WILL BE IN THE 3 TO 5 K/KM RANGE WHICH WILL SPARK SOME LAKE EFFECT
SNOW SHOWERS. THE DELTA T WILL SHRINK AS THE DAY WEARS ON AND
SURFACE HIGH PRESSURE ENTERING FROM THE WEST WILL SHUT DOWN ANY LAKE
EFFECT PROCESSES AFTER NOON. AN UPPER RIDGE WILL START TO BUILD IN
SUN-MON AND PROVIDE A WARMING TREND. THIS TREND SHOULD SURVIVE THE
NEXT LOW PRESSURE AND COLD FRONT EARLY NEXT WEEK AS 500 MB HEIGHTS
ONLY BRIEFLY DROP BELOW 560 DAM.

MARINE...
GUSTY WEST WINDS WILL CONTINUE TO SUBSIDE THIS EVENING AS LOW
PRESSURE OVER NORTHERN QUEBEC CONTINUES TO LIFT NORTHEAST AND A
RIDGE OF HIGH PRESSURE BUILDS INTO THE AREA. THE RIDGE WILL KEEP
WINDS FAIRLY LIGHT AND WAVE HEIGHTS FAIRLY LOW THROUGH THURSDAY
EVENING. A LOW PRESSURE SYSTEM AND ARCTIC COLD FRONT WILL THEN DROP
SOUTHEAST THROUGH THE CENTRAL GREAT LAKES VERY LATE THURSDAY NIGHT
THROUGH FRIDAY. NORTHERLY WINDS WILL BECOME STRONG BEHIND THE FRONT
FRIDAY AND FRIDAY NIGHT...WITH GUSTS LIKELY REACHING GALE FORCE OVER
MUCH OF LAKE HURON. A GALE WATCH MAY ALSO BE NEEDED FOR LAKE ST
CLAIR AND WESTERN LAKE ERIE. THE STRONG PERSISTENT NORTHERLY WINDS
WILL ALLOW WAVE HEIGHTS TO BUILD AS HIGH AS 14 FEET OVER THE
SOUTHERN PORTION OF LAKE HURON. WINDS WILL GRADUALLY DIMINISH ON
SATURDAY AS THE LOW MOVES EAST AND HIGH PRESSURE BUILDS INTO THE
AREA...HOWEVER LARGE WAVES WILL PERSIST OVER THE SOUTHERN PORTION OF
LAKE HURON THROUGH SATURDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-421-422-441-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ442-443-463-464.

LAKE ST CLAIR...NONE.

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

$$

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


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





000
FXUS63 KDTX 292305
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
705 PM EDT WED OCT 29 2014

.AVIATION...

//DISCUSSION...

SURFACE HIGH PRESSURE WILL EXTEND FROM MISSOURI NORTHWARD THROUGH
MINNESOTA DURING THE EVENING AND THEN MOVE OVER LOWER MICHIGAN BY
SUNRISE THURSDAY. THIS WILL RESULT IN DIMINISHING NORTHWEST WIND
OVER THE TERMINAL CORRIDOR AND A MORE SCATTERED COVERAGE OF VFR
BASED STRATOCU DURING THE NIGHT. PLAN TO MONITOR COVERAGE OF
CLOUDS OVER LAKE MICHIGAN BEFORE MAKING A MORE AGGRESSIVE LOW
CLOUD FORECAST FOR THURSDAY. LOW LEVEL WIND BACKING TOWARD THE
SOUTHWEST COULD BRING THOSE CLOUDS EASTWARD DURING THE MORNING IF
THEY CAN HOLD TOGETHER. OTHERWISE...VFR CEILING WILL INCREASE
COVERAGE DURING THE AFTERNOON BEFORE LIGHT RAIN BECOMES POSSIBLE
THURSDAY EVENING.

//DTW THRESHOLD THREATS...

* MODERATE CONFIDENCE IN CEILING BELOW 5000 FT THURSDAY AFTERNOON.

&&

.PREV DISCUSSION...ISSUED 403 PM EDT WED OCT 29 2014

SHORT TERM...TONIGHT

LINGERING RAIN SHOWERS AND GUSTY WINDS ACROSS SOUTHEAST MICHIGAN
WILL BOTH COME TO AN END SHORTLY AFTER SUNSET. BRIEF RIDGING
OVERNIGHT WILL ALLOW WINDS TO BECOME MOSTLY CALM AND CLOUD COVER TO
DIMINISH SLIGHTLY AS DRY AIR FILTERS INTO THE REGION. WHILE THE DRY
AIR WILL KEEP LOW LEVEL CLOUDS FROM DEVELOPING...ENOUGH MID LEVEL
MOISTURE WILL STICK AROUND TO KEEP SOME MID CLOUDS IN THE FORECAST
GIVING WAY TO A PARTLY CLOUDY FORECAST OVERNIGHT. LOW TEMPERATURES
WILL BE MUCH COOLER THAN PREVIOUS NIGHTS...WITH LOWS DROPPING DOWN
INTO THE LOW TO MID 30S ACROSS SOUTHEAST MICHIGAN. THE METRO DETROIT
AREA HAS THE POTENTIAL TO BE SLIGHTLY WARMER WITH TEMPERATURES ONLY
DROPPING INTO THE UPPER 30S.

LONG TERM...THURSDAY THROUGH NEXT WEDNESDAY

SURFACE RIDGING WILL PERSIST THROUGH MUCH OF THURSDAY BEFORE
SHIFTING EAST. ALTHOUGH QUIET CONDITIONS ARE EXPECTED UNDER THE
RIDGE TOMORROW...CLOUDS WILL INCREASE THROUGH THE DAY AS MOISTURE
ARRIVES AHEAD OF A LOW PRESSURE SYSTEM DROPPING THROUGH CANADA...AND
AS THE UPPER WAVE OVER THE NORTHERN ROCKIES DIVES INTO MO/IL.
OVERALL...EXPECTING A MOISTLY CLOUDY DAY FROM THE AFTERNOON GOING
FORWARD. TEMPERATURES WILL REMAIN UNSEASONABLY COOL IN THE WAKE OF A
WEAK FRONT THAT PUSHED THROUGH EARLIER TODAY...WITH MAX TEMPERATURES
FROM THE MID 40S TO LOW 50S.

MAIN FOCUS IN THE EXTENDED WILL BE THE NEXT SYSTEM DROPPING THROUGH
AS IT WILL BRING WINDY CONDITIONS...EVEN COLDER TEMPERATURES...AND
OUR FIRST CHANCE FOR LIGHT SNOWFALL THIS SEASON. SEVERAL PIECES OF
ENERGY FROM WAY UP OVER THE NORTHWEST TERRITORIES AND NUNAVUT WILL
CONSOLIDATE AS THEY DIVE THROUGH CANADA AND AND THE WESTERN GREAT
LAKES LATE THURSDAY THROUGH FRIDAY. SURFACE LOW PRESSURE SYSTEM AND
COLD FRONT WILL DROP THROUGH LOWER MICHIGAN FRIDAY...WITH GFS/NAM
MODELS NOW TRENDING TOWARDS THE TIMING OF THE EURO/GEM. THIS LOOKS
TO PUSH THE COLD FRONT THROUGH EARLY IN THE DAY...MAINLY BETWEEN 14Z
AND 20Z. FGEN FORCING AND STRONG PVA WILL WORK WITH A MODEST THETA-E
PLUME SURGING UP AHEAD OF THE SYSTEM TO GENERATE WIDESPREAD SHOWERS.
MAIN ISSUE WILL BE THE VERY COLD AIR COMING IN WITH THE ARCTIC FRONT
AND HOW SOON PRECIPITATION WILL CHANGE FROM RAIN TO SNOW. CHANGEOVER
WILL OCCUR FROM NORTHWEST TO SOUTHEAST THROUGH THE DAY (MAX TEMPS
WILL BE REACHED EARLIER IN THE DAY FOR ALL BUT THE DETROIT AREA)
..LOOKING TO START BY MID-MORNING NEAR THE SAGINAW VALLEY AND
FINALLY SWITCH OVER NEAR THE CITY OF DETROIT DURING THE EARLY
EVENING. EXPECTING MOSTLY SNOW BY 800 PM...WITH POTENTIALLY AN
EXCEPTION IMMEDIATELY ALONG THE SHORE OF LAKE HURON WHERE WINDS WILL
BE OFF THE WARMER WATER.

MOISTURE WILL START TO PULL AWAY AS THE LOW EXITS EAST
HOWEVER...KEEPING SNOW AMOUNTS FAIRLY LIGHT. WILL HAVE TO
CONTINUALLY REASSESS THIS WITH EACH RUN OF NEW MODEL DATA HOWEVER.
STILL SOME UNCERTAINTY AS TO HOW MUCH WILL ACTUALLY STICK ON THE
GROUND WITH WARM ROAD TEMPERATURES AND PAVEMENT. BEST CHANCE FOR
LIGHT ACCUMULATIONS (A FEW TENTHS LOOK BEST RIGHT NOW) WILL BE ON
ELEVATED AND GRASSY SURFACES. STRONG WINDS WILL ALSO ACCOMPANY THE
FRONT AS THE ARRIVAL OF COLDER AIR STEEPENS LAPSE RATES AND DEEPENS
THE BOUNDARY LAYER. FORECAST SOUNDINGS SUGGEST GUSTS TO 40 MPH...BUT
WILL NEED TO WATCH THE STRONGER EURO MODEL...WHICH HAS A CORE OF 40-
50 KNOTS AS LOW AS 925 MB. TEMPERATURES WILL BECOME QUITE CHILLY BY
FRIDAY EVENING...ESPECIALLY WHEN THE GUSTY WINDS ARE FACTORED IN.
EVENING WIND CHILLS LOOK TO RUN BETWEEN THE MID 20S TO LOW 30S. THIS
IS IN ADDITION TO LINGERING RAIN AND SNOW SHOWERS.

LAKE EFFECT RAIN/SNOW SHOWERS WILL BE POSSIBLE DURING THE EVENING
AND OVERNIGHT OFF LAKE HURON AFTER THE LOW PULLS AWAY...WITH STEEP
LAPSE RATES OVER THE WATER AND PERSISTENT NORTHERLY FLOW OFF THE
LAKE. THIS MAY BRING ADDITIONAL LIGHT ACCUMULATIONS.

THE WEEKEND REMAINS VERY COLD IN THE EXTENDED FORECAST. COLD AIR
ADVECTION DOES SLOW DOWN...BUT THE 0-1KM LAPSE RATES OVER LAKE HURON
WILL BE IN THE 3 TO 5 K/KM RANGE WHICH WILL SPARK SOME LAKE EFFECT
SNOW SHOWERS. THE DELTA T WILL SHRINK AS THE DAY WEARS ON AND
SURFACE HIGH PRESSURE ENTERING FROM THE WEST WILL SHUT DOWN ANY LAKE
EFFECT PROCESSES AFTER NOON. AN UPPER RIDGE WILL START TO BUILD IN
SUN-MON AND PROVIDE A WARMING TREND. THIS TREND SHOULD SURVIVE THE
NEXT LOW PRESSURE AND COLD FRONT EARLY NEXT WEEK AS 500 MB HEIGHTS
ONLY BRIEFLY DROP BELOW 560 DAM.

MARINE...
GUSTY WEST WINDS WILL CONTINUE TO SUBSIDE THIS EVENING AS LOW
PRESSURE OVER NORTHERN QUEBEC CONTINUES TO LIFT NORTHEAST AND A
RIDGE OF HIGH PRESSURE BUILDS INTO THE AREA. THE RIDGE WILL KEEP
WINDS FAIRLY LIGHT AND WAVE HEIGHTS FAIRLY LOW THROUGH THURSDAY
EVENING. A LOW PRESSURE SYSTEM AND ARCTIC COLD FRONT WILL THEN DROP
SOUTHEAST THROUGH THE CENTRAL GREAT LAKES VERY LATE THURSDAY NIGHT
THROUGH FRIDAY. NORTHERLY WINDS WILL BECOME STRONG BEHIND THE FRONT
FRIDAY AND FRIDAY NIGHT...WITH GUSTS LIKELY REACHING GALE FORCE OVER
MUCH OF LAKE HURON. A GALE WATCH MAY ALSO BE NEEDED FOR LAKE ST
CLAIR AND WESTERN LAKE ERIE. THE STRONG PERSISTENT NORTHERLY WINDS
WILL ALLOW WAVE HEIGHTS TO BUILD AS HIGH AS 14 FEET OVER THE
SOUTHERN PORTION OF LAKE HURON. WINDS WILL GRADUALLY DIMINISH ON
SATURDAY AS THE LOW MOVES EAST AND HIGH PRESSURE BUILDS INTO THE
AREA...HOWEVER LARGE WAVES WILL PERSIST OVER THE SOUTHERN PORTION OF
LAKE HURON THROUGH SATURDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-421-422-441-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ442-443-463-464.

LAKE ST CLAIR...NONE.

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

$$

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


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





000
FXUS63 KDTX 292305
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
705 PM EDT WED OCT 29 2014

.AVIATION...

//DISCUSSION...

SURFACE HIGH PRESSURE WILL EXTEND FROM MISSOURI NORTHWARD THROUGH
MINNESOTA DURING THE EVENING AND THEN MOVE OVER LOWER MICHIGAN BY
SUNRISE THURSDAY. THIS WILL RESULT IN DIMINISHING NORTHWEST WIND
OVER THE TERMINAL CORRIDOR AND A MORE SCATTERED COVERAGE OF VFR
BASED STRATOCU DURING THE NIGHT. PLAN TO MONITOR COVERAGE OF
CLOUDS OVER LAKE MICHIGAN BEFORE MAKING A MORE AGGRESSIVE LOW
CLOUD FORECAST FOR THURSDAY. LOW LEVEL WIND BACKING TOWARD THE
SOUTHWEST COULD BRING THOSE CLOUDS EASTWARD DURING THE MORNING IF
THEY CAN HOLD TOGETHER. OTHERWISE...VFR CEILING WILL INCREASE
COVERAGE DURING THE AFTERNOON BEFORE LIGHT RAIN BECOMES POSSIBLE
THURSDAY EVENING.

//DTW THRESHOLD THREATS...

* MODERATE CONFIDENCE IN CEILING BELOW 5000 FT THURSDAY AFTERNOON.

&&

.PREV DISCUSSION...ISSUED 403 PM EDT WED OCT 29 2014

SHORT TERM...TONIGHT

LINGERING RAIN SHOWERS AND GUSTY WINDS ACROSS SOUTHEAST MICHIGAN
WILL BOTH COME TO AN END SHORTLY AFTER SUNSET. BRIEF RIDGING
OVERNIGHT WILL ALLOW WINDS TO BECOME MOSTLY CALM AND CLOUD COVER TO
DIMINISH SLIGHTLY AS DRY AIR FILTERS INTO THE REGION. WHILE THE DRY
AIR WILL KEEP LOW LEVEL CLOUDS FROM DEVELOPING...ENOUGH MID LEVEL
MOISTURE WILL STICK AROUND TO KEEP SOME MID CLOUDS IN THE FORECAST
GIVING WAY TO A PARTLY CLOUDY FORECAST OVERNIGHT. LOW TEMPERATURES
WILL BE MUCH COOLER THAN PREVIOUS NIGHTS...WITH LOWS DROPPING DOWN
INTO THE LOW TO MID 30S ACROSS SOUTHEAST MICHIGAN. THE METRO DETROIT
AREA HAS THE POTENTIAL TO BE SLIGHTLY WARMER WITH TEMPERATURES ONLY
DROPPING INTO THE UPPER 30S.

LONG TERM...THURSDAY THROUGH NEXT WEDNESDAY

SURFACE RIDGING WILL PERSIST THROUGH MUCH OF THURSDAY BEFORE
SHIFTING EAST. ALTHOUGH QUIET CONDITIONS ARE EXPECTED UNDER THE
RIDGE TOMORROW...CLOUDS WILL INCREASE THROUGH THE DAY AS MOISTURE
ARRIVES AHEAD OF A LOW PRESSURE SYSTEM DROPPING THROUGH CANADA...AND
AS THE UPPER WAVE OVER THE NORTHERN ROCKIES DIVES INTO MO/IL.
OVERALL...EXPECTING A MOISTLY CLOUDY DAY FROM THE AFTERNOON GOING
FORWARD. TEMPERATURES WILL REMAIN UNSEASONABLY COOL IN THE WAKE OF A
WEAK FRONT THAT PUSHED THROUGH EARLIER TODAY...WITH MAX TEMPERATURES
FROM THE MID 40S TO LOW 50S.

MAIN FOCUS IN THE EXTENDED WILL BE THE NEXT SYSTEM DROPPING THROUGH
AS IT WILL BRING WINDY CONDITIONS...EVEN COLDER TEMPERATURES...AND
OUR FIRST CHANCE FOR LIGHT SNOWFALL THIS SEASON. SEVERAL PIECES OF
ENERGY FROM WAY UP OVER THE NORTHWEST TERRITORIES AND NUNAVUT WILL
CONSOLIDATE AS THEY DIVE THROUGH CANADA AND AND THE WESTERN GREAT
LAKES LATE THURSDAY THROUGH FRIDAY. SURFACE LOW PRESSURE SYSTEM AND
COLD FRONT WILL DROP THROUGH LOWER MICHIGAN FRIDAY...WITH GFS/NAM
MODELS NOW TRENDING TOWARDS THE TIMING OF THE EURO/GEM. THIS LOOKS
TO PUSH THE COLD FRONT THROUGH EARLY IN THE DAY...MAINLY BETWEEN 14Z
AND 20Z. FGEN FORCING AND STRONG PVA WILL WORK WITH A MODEST THETA-E
PLUME SURGING UP AHEAD OF THE SYSTEM TO GENERATE WIDESPREAD SHOWERS.
MAIN ISSUE WILL BE THE VERY COLD AIR COMING IN WITH THE ARCTIC FRONT
AND HOW SOON PRECIPITATION WILL CHANGE FROM RAIN TO SNOW. CHANGEOVER
WILL OCCUR FROM NORTHWEST TO SOUTHEAST THROUGH THE DAY (MAX TEMPS
WILL BE REACHED EARLIER IN THE DAY FOR ALL BUT THE DETROIT AREA)
..LOOKING TO START BY MID-MORNING NEAR THE SAGINAW VALLEY AND
FINALLY SWITCH OVER NEAR THE CITY OF DETROIT DURING THE EARLY
EVENING. EXPECTING MOSTLY SNOW BY 800 PM...WITH POTENTIALLY AN
EXCEPTION IMMEDIATELY ALONG THE SHORE OF LAKE HURON WHERE WINDS WILL
BE OFF THE WARMER WATER.

MOISTURE WILL START TO PULL AWAY AS THE LOW EXITS EAST
HOWEVER...KEEPING SNOW AMOUNTS FAIRLY LIGHT. WILL HAVE TO
CONTINUALLY REASSESS THIS WITH EACH RUN OF NEW MODEL DATA HOWEVER.
STILL SOME UNCERTAINTY AS TO HOW MUCH WILL ACTUALLY STICK ON THE
GROUND WITH WARM ROAD TEMPERATURES AND PAVEMENT. BEST CHANCE FOR
LIGHT ACCUMULATIONS (A FEW TENTHS LOOK BEST RIGHT NOW) WILL BE ON
ELEVATED AND GRASSY SURFACES. STRONG WINDS WILL ALSO ACCOMPANY THE
FRONT AS THE ARRIVAL OF COLDER AIR STEEPENS LAPSE RATES AND DEEPENS
THE BOUNDARY LAYER. FORECAST SOUNDINGS SUGGEST GUSTS TO 40 MPH...BUT
WILL NEED TO WATCH THE STRONGER EURO MODEL...WHICH HAS A CORE OF 40-
50 KNOTS AS LOW AS 925 MB. TEMPERATURES WILL BECOME QUITE CHILLY BY
FRIDAY EVENING...ESPECIALLY WHEN THE GUSTY WINDS ARE FACTORED IN.
EVENING WIND CHILLS LOOK TO RUN BETWEEN THE MID 20S TO LOW 30S. THIS
IS IN ADDITION TO LINGERING RAIN AND SNOW SHOWERS.

LAKE EFFECT RAIN/SNOW SHOWERS WILL BE POSSIBLE DURING THE EVENING
AND OVERNIGHT OFF LAKE HURON AFTER THE LOW PULLS AWAY...WITH STEEP
LAPSE RATES OVER THE WATER AND PERSISTENT NORTHERLY FLOW OFF THE
LAKE. THIS MAY BRING ADDITIONAL LIGHT ACCUMULATIONS.

THE WEEKEND REMAINS VERY COLD IN THE EXTENDED FORECAST. COLD AIR
ADVECTION DOES SLOW DOWN...BUT THE 0-1KM LAPSE RATES OVER LAKE HURON
WILL BE IN THE 3 TO 5 K/KM RANGE WHICH WILL SPARK SOME LAKE EFFECT
SNOW SHOWERS. THE DELTA T WILL SHRINK AS THE DAY WEARS ON AND
SURFACE HIGH PRESSURE ENTERING FROM THE WEST WILL SHUT DOWN ANY LAKE
EFFECT PROCESSES AFTER NOON. AN UPPER RIDGE WILL START TO BUILD IN
SUN-MON AND PROVIDE A WARMING TREND. THIS TREND SHOULD SURVIVE THE
NEXT LOW PRESSURE AND COLD FRONT EARLY NEXT WEEK AS 500 MB HEIGHTS
ONLY BRIEFLY DROP BELOW 560 DAM.

MARINE...
GUSTY WEST WINDS WILL CONTINUE TO SUBSIDE THIS EVENING AS LOW
PRESSURE OVER NORTHERN QUEBEC CONTINUES TO LIFT NORTHEAST AND A
RIDGE OF HIGH PRESSURE BUILDS INTO THE AREA. THE RIDGE WILL KEEP
WINDS FAIRLY LIGHT AND WAVE HEIGHTS FAIRLY LOW THROUGH THURSDAY
EVENING. A LOW PRESSURE SYSTEM AND ARCTIC COLD FRONT WILL THEN DROP
SOUTHEAST THROUGH THE CENTRAL GREAT LAKES VERY LATE THURSDAY NIGHT
THROUGH FRIDAY. NORTHERLY WINDS WILL BECOME STRONG BEHIND THE FRONT
FRIDAY AND FRIDAY NIGHT...WITH GUSTS LIKELY REACHING GALE FORCE OVER
MUCH OF LAKE HURON. A GALE WATCH MAY ALSO BE NEEDED FOR LAKE ST
CLAIR AND WESTERN LAKE ERIE. THE STRONG PERSISTENT NORTHERLY WINDS
WILL ALLOW WAVE HEIGHTS TO BUILD AS HIGH AS 14 FEET OVER THE
SOUTHERN PORTION OF LAKE HURON. WINDS WILL GRADUALLY DIMINISH ON
SATURDAY AS THE LOW MOVES EAST AND HIGH PRESSURE BUILDS INTO THE
AREA...HOWEVER LARGE WAVES WILL PERSIST OVER THE SOUTHERN PORTION OF
LAKE HURON THROUGH SATURDAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-421-422-441-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ442-443-463-464.

LAKE ST CLAIR...NONE.

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

$$

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


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





000
FXUS63 KDTX 292003
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
403 PM EDT WED OCT 29 2014

.SHORT TERM...TONIGHT

LINGERING RAIN SHOWERS AND GUSTY WINDS ACROSS SOUTHEAST MICHIGAN
WILL BOTH COME TO AN END SHORTLY AFTER SUNSET. BRIEF RIDGING
OVERNIGHT WILL ALLOW WINDS TO BECOME MOSTLY CALM AND CLOUD COVER TO
DIMINISH SLIGHTLY AS DRY AIR FILTERS INTO THE REGION. WHILE THE DRY
AIR WILL KEEP LOW LEVEL CLOUDS FROM DEVELOPING...ENOUGH MID LEVEL
MOISTURE WILL STICK AROUND TO KEEP SOME MID CLOUDS IN THE FORECAST
GIVING WAY TO A PARTLY CLOUDY FORECAST OVERNIGHT. LOW TEMPERATURES
WILL BE MUCH COOLER THAN PREVIOUS NIGHTS...WITH LOWS DROPPING DOWN
INTO THE LOW TO MID 30S ACROSS SOUTHEAST MICHIGAN. THE METRO DETROIT
AREA HAS THE POTENTIAL TO BE SLIGHTLY WARMER WITH TEMPERATURES ONLY
DROPPING INTO THE UPPER 30S.

&&

.LONG TERM...THURSDAY THROUGH NEXT WEDNESDAY

SURFACE RIDGING WILL PERSIST THROUGH MUCH OF THURSDAY BEFORE
SHIFTING EAST. ALTHOUGH QUIET CONDITIONS ARE EXPECTED UNDER THE
RIDGE TOMORROW...CLOUDS WILL INCREASE THROUGH THE DAY AS MOISTURE
ARRIVES AHEAD OF A LOW PRESSURE SYSTEM DROPPING THROUGH CANADA...AND
AS THE UPPER WAVE OVER THE NORTHERN ROCKIES DIVES INTO MO/IL.
OVERALL...EXPECTING A MOISTLY CLOUDY DAY FROM THE AFTERNOON GOING
FORWARD. TEMPERATURES WILL REMAIN UNSEASONABLY COOL IN THE WAKE OF A
WEAK FRONT THAT PUSHED THROUGH EARLIER TODAY...WITH MAX TEMPERATURES
FROM THE MID 40S TO LOW 50S.

MAIN FOCUS IN THE EXTENDED WILL BE THE NEXT SYSTEM DROPPING THROUGH
AS IT WILL BRING WINDY CONDITIONS...EVEN COLDER TEMPERATURES...AND
OUR FIRST CHANCE FOR LIGHT SNOWFALL THIS SEASON. SEVERAL PIECES OF
ENERGY FROM WAY UP OVER THE NORTHWEST TERRITORIES AND NUNAVUT WILL
CONSOLIDATE AS THEY DIVE THROUGH CANADA AND AND THE WESTERN GREAT
LAKES LATE THURSDAY THROUGH FRIDAY. SURFACE LOW PRESSURE SYSTEM AND
COLD FRONT WILL DROP THROUGH LOWER MICHIGAN FRIDAY...WITH GFS/NAM
MODELS NOW TRENDING TOWARDS THE TIMING OF THE EURO/GEM. THIS LOOKS
TO PUSH THE COLD FRONT THROUGH EARLY IN THE DAY...MAINLY BETWEEN 14Z
AND 20Z. FGEN FORCING AND STRONG PVA WILL WORK WITH A MODEST THETA-E
PLUME SURGING UP AHEAD OF THE SYSTEM TO GENERATE WIDESPREAD SHOWERS.
MAIN ISSUE WILL BE THE VERY COLD AIR COMING IN WITH THE ARCTIC FRONT
AND HOW SOON PRECIPITATION WILL CHANGE FROM RAIN TO SNOW. CHANGEOVER
WILL OCCUR FROM NORTHWEST TO SOUTHEAST THROUGH THE DAY (MAX TEMPS
WILL BE REACHED EARLIER IN THE DAY FOR ALL BUT THE DETROIT AREA)
...LOOKING TO START BY MID-MORNING NEAR THE SAGINAW VALLEY AND
FINALLY SWITCH OVER NEAR THE CITY OF DETROIT DURING THE EARLY
EVENING. EXPECTING MOSTLY SNOW BY 800 PM...WITH POTENTIALLY AN
EXCEPTION IMMEDIATELY ALONG THE SHORE OF LAKE HURON WHERE WINDS WILL
BE OFF THE WARMER WATER.

MOISTURE WILL START TO PULL AWAY AS THE LOW EXITS EAST
HOWEVER...KEEPING SNOW AMOUNTS FAIRLY LIGHT. WILL HAVE TO
CONTINUALLY REASSESS THIS WITH EACH RUN OF NEW MODEL DATA HOWEVER.
STILL SOME UNCERTAINTY AS TO HOW MUCH WILL ACTUALLY STICK ON THE
GROUND WITH WARM ROAD TEMPERATURES AND PAVEMENT. BEST CHANCE FOR
LIGHT ACCUMULATIONS (A FEW TENTHS LOOK BEST RIGHT NOW) WILL BE ON
ELEVATED AND GRASSY SURFACES. STRONG WINDS WILL ALSO ACCOMPANY THE
FRONT AS THE ARRIVAL OF COLDER AIR STEEPENS LAPSE RATES AND DEEPENS
THE BOUNDARY LAYER. FORECAST SOUNDINGS SUGGEST GUSTS TO 40 MPH...BUT
WILL NEED TO WATCH THE STRONGER EURO MODEL...WHICH HAS A CORE OF 40-
50 KNOTS AS LOW AS 925 MB. TEMPERATURES WILL BECOME QUITE CHILLY BY
FRIDAY EVENING...ESPECIALLY WHEN THE GUSTY WINDS ARE FACTORED IN.
EVENING WIND CHILLS LOOK TO RUN BETWEEN THE MID 20S TO LOW 30S. THIS
IS IN ADDITION TO LINGERING RAIN AND SNOW SHOWERS.

LAKE EFFECT RAIN/SNOW SHOWERS WILL BE POSSIBLE DURING THE EVENING
AND OVERNIGHT OFF LAKE HURON AFTER THE LOW PULLS AWAY...WITH STEEP
LAPSE RATES OVER THE WATER AND PERSISTENT NORTHERLY FLOW OFF THE
LAKE. THIS MAY BRING ADDITIONAL LIGHT ACCUMULATIONS.

THE WEEKEND REMAINS VERY COLD IN THE EXTENDED FORECAST. COLD AIR
ADVECTION DOES SLOW DOWN...BUT THE 0-1KM LAPSE RATES OVER LAKE HURON
WILL BE IN THE 3 TO 5 K/KM RANGE WHICH WILL SPARK SOME LAKE EFFECT
SNOW SHOWERS. THE DELTA T WILL SHRINK AS THE DAY WEARS ON AND
SURFACE HIGH PRESSURE ENTERING FROM THE WEST WILL SHUT DOWN ANY LAKE
EFFECT PROCESSES AFTER NOON. AN UPPER RIDGE WILL START TO BUILD IN
SUN-MON AND PROVIDE A WARMING TREND. THIS TREND SHOULD SURVIVE THE
NEXT LOW PRESSURE AND COLD FRONT EARLY NEXT WEEK AS 500 MB HEIGHTS
ONLY BRIEFLY DROP BELOW 560 DAM.

&&

.MARINE...
GUSTY WEST WINDS WILL CONTINUE TO SUBSIDE THIS EVENING AS LOW
PRESSURE OVER NORTHERN QUEBEC CONTINUES TO LIFT NORTHEAST AND A
RIDGE OF HIGH PRESSURE BUILDS INTO THE AREA. THE RIDGE WILL KEEP
WINDS FAIRLY LIGHT AND WAVE HEIGHTS FAIRLY LOW THROUGH THURSDAY
EVENING. A LOW PRESSURE SYSTEM AND ARCTIC COLD FRONT WILL THEN DROP
SOUTHEAST THROUGH THE CENTRAL GREAT LAKES VERY LATE THURSDAY NIGHT
THROUGH FRIDAY. NORTHERLY WINDS WILL BECOME STRONG BEHIND THE FRONT
FRIDAY AND FRIDAY NIGHT...WITH GUSTS LIKELY REACHING GALE FORCE OVER
MUCH OF LAKE HURON. A GALE WATCH MAY ALSO BE NEEDED FOR LAKE ST
CLAIR AND WESTERN LAKE ERIE. THE STRONG PERSISTENT NORTHERLY WINDS
WILL ALLOW WAVE HEIGHTS TO BUILD AS HIGH AS 14 FEET OVER THE
SOUTHERN PORTION OF LAKE HURON. WINDS WILL GRADUALLY DIMINISH ON
SATURDAY AS THE LOW MOVES EAST AND HIGH PRESSURE BUILDS INTO THE
AREA...HOWEVER LARGE WAVES WILL PERSIST OVER THE SOUTHERN PORTION OF
LAKE HURON THROUGH SATURDAY.

&&

.AVIATION...ISSUED 131 PM EDT WED OCT 29 2014

//DISCUSSION...

EXPECTING BROKEN CEILINGS TO STICK AROUND THROUGH THE AFTERNOON
ACROSS ALL THE TAF SITES. WIND GUSTS ARE ALSO EXPECTED TO REACH UP
TO 20 TO 25 KNOTS THIS AFTERNOON. WEAK SURFACE RIDGING OVERNIGHT WILL
ALLOW WINDS TO DIMINISH AND CLOUDS TO THIN SLIGHTLY AS DRIER AIR
FILTERS OVER THE REGION. HOWEVER...EVEN WITH THE DRY AIR FILTERING
IN TONIGHT...WILL STILL EXPECT AT LEAST SCATTERED CLOUD DECK TO
REMAIN ACROSS SOUTHEAST MICHIGAN. CLOUDS BEGIN TO BUILD BACK OVER
THE AREA LATE TOMORROW MORNING AS THE NEXT DISTURBANCE ARRIVES.

//DTW THRESHOLD THREATS...

* MODERATE PROBABILITY THAT CEILINGS WILL REMAIN BELOW 5000 FT
  BETWEEN 18Z WEDNESDAY AND 00Z THURSDAY.

* LOW CONFIDENCE THAT CEILINGS WILL DROP BELOW 5000 FT THURSDAY
  AFTERNOON.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-421-422-441-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ442-443-463-464.

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

$$

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


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





000
FXUS63 KDTX 291731
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
131 PM EDT WED OCT 29 2014


.AVIATION...

//DISCUSSION...

EXPECTING BROKEN CEILINGS TO STICK AROUND THROUGH THE AFTERNOON
ACROSS ALL THE TAF SITES. WIND GUSTS ARE ALSO EXPECTED TO REACH UP
TO 20 TO 25 KNOTS THIS AFTERNOON. WEAK SURFACE RIDGING OVERNIGHT WILL
ALLOW WINDS TO DIMINISH AND CLOUDS TO THIN SLIGHTLY AS DRIER AIR
FILTERS OVER THE REGION. HOWEVER...EVEN WITH THE DRY AIR FILTERING
IN TONIGHT...WILL STILL EXPECT AT LEAST SCATTERED CLOUD DECK TO
REMAIN ACROSS SOUTHEAST MICHIGAN. CLOUDS BEGIN TO BUILD BACK OVER
THE AREA LATE TOMORROW MORNING AS THE NEXT DISTURBANCE ARRIVES.

//DTW THRESHOLD THREATS...

* MODERATE PROBABILITY THAT CEILINGS WILL REMAIN BELOW 5000 FT
  BETWEEN 18Z WEDNESDAY AND 00Z THURSDAY.

* LOW CONFIDENCE THAT CEILINGS WILL DROP BELOW 5000 FT THURSDAY
  AFTERNOON.

&&

.PREV DISCUSSION...ISSUED 352 AM EDT WED OCT 29 2014

SHORT TERM...TODAY AND TONIGHT

DESPITE THE PASSAGE OF A COLD FRONT YESTERDAY...COLD AIR ADVECTION
WILL CONTINUE TODAY AS A LOW LEVEL TROUGH TURNS 850 MB WINDS FROM A
WESTERLY TO A NORTHWESTERLY DIRECTION...FURTHER DROPPING 850 MB
TEMPERATURES INTO THE SINGLE DIGITS BELOW ZERO. SKIES THIS MORNING
WILL START OUT AS PARTLY TO MOSTLY CLOUDY...DEPENDING ON LOCATION AS
THERE ARE CURRENTLY SEVERAL BREAKS IN THE CLOUDS. SKIES SHOULD
QUICKLY BECOME BROKEN TO OVERCAST LATER THIS MORNING AS COLD AIR
ALOFT...LINGERING 850 MB MOISTURE AND CONTINUED CYCLONIC FLOW CREATE
CONDITIONS CONDUCIVE FOR A PRETTY SOLID DECK OF STRATOCUMULUS TO
FORM. THE CONTINUED COLD AIR ADVECTION AND ABUNDANT CLOUD COVER WILL
SEVERELY LIMIT THE DIURNAL RANGE IN TEMPERATURES AS HIGHS ONLY TOP
OUT AROUND 50 DEGREES THIS AFTERNOON.

WITH THE LOSS OF DAYTIME HEATING THE DIURNALLY DRIVEN CLOUDS WILL
DISSIPATE AS DRIER AIR AND SURFACE RIDGING BUILD IN FROM
THE WEST. HOWEVER A COMPLETE CLEARING IS NOT EXPECTED AS 850 MB
MOISTURE REMAINS OVER THE CENTRAL GREAT LAKES WITH NORTHWEST FLOW
ALOFT. THE AFOREMENTIONED RIDGING WILL CAUSE SURFACE WINDS TO
BECOME LIGHT...THIS COMBINED WITH SOME BREAKS IN THE CLOUDS WILL
CAUSE OVERNIGHT LOWS TO FALL INTO THE LOWER TO MIDDLE 30S ACROSS
SOUTHEAST MICHIGAN.

LONG TERM...

STRONG POLAR PV ANOMALY DESCENDING FROM THE NORTHWEST
TERRITORIES/NUNAVUT TODAY...AND DROPPING SOUTH THROUGH THE AREA ON
FRIDAY...DELIVERING THE FIRST SNOWFLAKES OF THE FALL SEASON TO
SOUTHEAST MICHIGAN. STILL NEED TO TO FINE TUNE EXACT TRACK OF
DEVELOPING 500 MB LOW CENTER WHICH WILL DICTATE SYNOPTIC SUPPORT OF
PRECIPITATION VS MESOSCALE LAKE EFFECT OFF LAKE HURON. A LOOKED AT
THE STANDARDIZED ANOMALIES OF 500 MB HEIGHTS AND 850 MB TEMPS DOES
NOT SHOW ANYTHING TERRIBLY UNUSUAL (-1.5)/NON-RECORD BREAKING...AND
THUS MAKING THIS A VERY DIFFICULT FORECAST IN DETERMINING WHAT IF
ANY SNOW ACCUMULATIONS WILL OCCUR. NEGATIVES FOR THE EVENT INCLUDE
THE UNFAVORABLE AFTERNOON TIMING...WARM MARINE LAYER/WATERS OF LAKE
HURON (LOWER 50S)...AND WARM GROUND (SOIL TEMPS 45-50). WILL BE
TRUSTING THE SURFACE/NEAR SURFACE PROFILES OF THE 00Z
NAM/EURO/CANADIAN...WHICH OBVIOUSLY ARE SUBJECT TO BE IN
ERROR/REVISED. THIS GUIDANCE SUGGEST SURFACE TEMPERATURES
REMAINING ABOVE FREEZING THROUGH 00Z SATURDAY...ALTHOUGH EURO HAS
THE BEST SUPPORT FOR SNOW AS SURFACE WET BULB TEMPS FALL BELOW
FREEZING ALONG AND WEST OF U.S. 23 BY 00Z SATURDAY. EVEN DURING THE
EVENING...THE LOW LEVEL NORTHEAST WINDS OF LAKE HURON LOOK TO KEEP
EASTERN HALF OF THE CWA ABOVE FREEZING. THROW IN THE FACT THE GFS IS
STRONGER/MILDER AND FARTHER WEST (ALTHOUGH PREFERENCE IS WITH
EURO/CANADIAN SOLUTIONS)...AND WILL SKEW THE FORECAST ON THE WET
SIDE FOR MOST OF FRIDAY...WITH STILL SOME SNOW MIXING IN/CHANGING
OVER TOWARD SUNSET...AS 850 MB TEMPS FALL INTO THE -8 TO -10 C
RANGE. BETTER CHANCE OF ACCUMULATING SNOW SHOWERS FRIDAY NIGHT AS
LAKE EFFECT LIKELY PERSISTS AND LOW LEVEL COLDER AIR CONTINUES TO
BLEED IN UNDER NIGHT-TIME SETTING. EXTENSION OF THE IRISH
HILLS/HIGHER TERRAIN THE FAVORED LOCATIONS FOR LIGHT SNOW
ACCUMULATIONS.

SATURDAY IS A TRICKY FORECAST AS WELL...AS WE WILL BE ON THE WESTERN
EDGE OF THE LARGE UPPER LEVEL CIRCULATION. WITH LOW LEVEL FLOW STILL
OUT OF THE NORTHEAST...AND COLD AIRMASS (NEGATIVE MID TO UPPER
SINGLES AT 850 MB)...LIKELY WILL SEE ADDITIONAL SCATTERED SNOW/RAIN
SHOWERS AROUND...ESPECIALLY DURING MORNING HOURS.

MARINE...

SOUTHWEST WINDS OF 15 TO 25 KNOTS TODAY WILL GRADUALLY EASE AND
SHIFT TO THE NORTHWEST TONIGHT...BECOMING LIGHT ON THURSDAY. THIS
LULL IN THE WINDS WILL BE SHORT LIVED...AS AN ARCTIC FRONT PASSES
THROUGH THE CENTRAL GREAT LAKES ON FRIDAY. NORTHERLY GUSTS TO GALES
APPEAR LIKELY FRIDAY AFTERNOON INTO FRIDAY NIGHT OVER THE SOUTHERN
TWO THIRDS OF LAKE HURON DURING THIS TIME WITH SIGNIFICANT WAVE
HEIGHTS OF 5 TO 10 FEET OVER SOUTHERN LAKE HURON. HAVE GONE AHEAD
AND ISSUED GALE WATCHES WITH THIS FORECAST PACKAGE. ALTHOUGH WINDS
WILL GRADUALLY DIMINISH ON SATURDAY...THE NORTHEAST WIND DIRECTION
WILL MAINTAIN HIGHER WAVES ALONG NEARSHORE WATERS. HIGH PRESSURE
BUILDING IN ON SUNDAY WILL ASSURE LIGHT WINDS.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ463-464.

     SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR LHZ421-422-
     441.

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

$$

AVIATION.....RK
SHORT TERM...KURIMSKI
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 291122
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
722 AM EDT WED OCT 29 2014


.AVIATION...

//DISCUSSION...

CLOUDS CONTINUE TO BE AN ISSUE WITH A BREAK IN THE CLOUDS CURRENTLY
OVER THE METRO AIRPORTS WITH SOLID OVERCAST OVER MBS. SKIES ARE
EXPECTED TO BECOME MOSTLY CLOUDY AT ALL THE TAF SITES SHORTLY AFTER
SUNRISE AS DIURNAL CUMULUS DEVELOP UNDER THE COOL UNSTABLE AIRMASS
IN PLACE ACROSS THE CENTRAL GREAT LAKES. DAYTIME HEATING WILL ALSO
BRING HIGHER GUSTS DOWN TO THE SURFACE...WITH WESTERLY WINDS GUSTING
TO 20 KNOTS AT TIMES. DESPITE THE LOSS OF DAYTIME HEATING...CLOUDS
ARE NOT EXPECTED TO SCATTER OUT UNTIL LATER TONIGHT WHEN RIDGING
BRINGS DRIER AIR TO THE SOUTHERN AIRPORTS. FURTHER NORTH A CONTINUED
FLOW OFF THE GREAT LAKES WILL MAINTAIN CLOUDY CONDITIONS THROUGH THE
NIGHT. THE RIDGE WILL CAUSE WINDS TO EASE TO AROUND 5 KNOTS JUST
AFTER MIDNIGHT.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE ON CEILING BELOW 5000 FT THROUGH THIS EVENING.

&&

.PREV DISCUSSION...ISSUED 352 AM EDT WED OCT 29 2014

SHORT TERM...TODAY AND TONIGHT

DESPITE THE PASSAGE OF A COLD FRONT YESTERDAY...COLD AIR ADVECTION
WILL CONTINUE TODAY AS A LOW LEVEL TROUGH TURNS 850 MB WINDS FROM A
WESTERLY TO A NORTHWESTERLY DIRECTION...FURTHER DROPPING 850 MB
TEMPERATURES INTO THE SINGLE DIGITS BELOW ZERO. SKIES THIS MORNING
WILL START OUT AS PARTLY TO MOSTLY CLOUDY...DEPENDING ON LOCATION AS
THERE ARE CURRENTLY SEVERAL BREAKS IN THE CLOUDS. SKIES SHOULD
QUICKLY BECOME BROKEN TO OVERCAST LATER THIS MORNING AS COLD AIR
ALOFT...LINGERING 850 MB MOISTURE AND CONTINUED CYCLONIC FLOW CREATE
CONDITIONS CONDUCIVE FOR A PRETTY SOLID DECK OF STRATOCUMULUS TO
FORM. THE CONTINUED COLD AIR ADVECTION AND ABUNDANT CLOUD COVER WILL
SEVERELY LIMIT THE DIURNAL RANGE IN TEMPERATURES AS HIGHS ONLY TOP
OUT AROUND 50 DEGREES THIS AFTERNOON.

WITH THE LOSS OF DAYTIME HEATING THE DIURNALLY DRIVEN CLOUDS WILL
DISSIPATE AS DRIER AIR AND SURFACE RIDGING BUILD IN FROM
THE WEST. HOWEVER A COMPLETE CLEARING IS NOT EXPECTED AS 850 MB
MOISTURE REMAINS OVER THE CENTRAL GREAT LAKES WITH NORTHWEST FLOW
ALOFT. THE AFOREMENTIONED RIDGING WILL CAUSE SURFACE WINDS TO
BECOME LIGHT...THIS COMBINED WITH SOME BREAKS IN THE CLOUDS WILL
CAUSE OVERNIGHT LOWS TO FALL INTO THE LOWER TO MIDDLE 30S ACROSS
SOUTHEAST MICHIGAN.

LONG TERM...

STRONG POLAR PV ANOMALY DESCENDING FROM THE NORTHWEST
TERRITORIES/NUNAVUT TODAY...AND DROPPING SOUTH THROUGH THE AREA ON
FRIDAY...DELIVERING THE FIRST SNOWFLAKES OF THE FALL SEASON TO
SOUTHEAST MICHIGAN. STILL NEED TO TO FINE TUNE EXACT TRACK OF
DEVELOPING 500 MB LOW CENTER WHICH WILL DICTATE SYNOPTIC SUPPORT OF
PRECIPITATION VS MESOSCALE LAKE EFFECT OFF LAKE HURON. A LOOKED AT
THE STANDARDIZED ANOMALIES OF 500 MB HEIGHTS AND 850 MB TEMPS DOES
NOT SHOW ANYTHING TERRIBLY UNUSUAL (-1.5)/NON-RECORD BREAKING...AND
THUS MAKING THIS A VERY DIFFICULT FORECAST IN DETERMINING WHAT IF
ANY SNOW ACCUMULATIONS WILL OCCUR. NEGATIVES FOR THE EVENT INCLUDE
THE UNFAVORABLE AFTERNOON TIMING...WARM MARINE LAYER/WATERS OF LAKE
HURON (LOWER 50S)...AND WARM GROUND (SOIL TEMPS 45-50). WILL BE
TRUSTING THE SURFACE/NEAR SURFACE PROFILES OF THE 00Z
NAM/EURO/CANADIAN...WHICH OBVIOUSLY ARE SUBJECT TO BE IN
ERROR/REVISED. THIS GUIDANCE SUGGEST SURFACE TEMPERATURES
REMAINING ABOVE FREEZING THROUGH 00Z SATURDAY...ALTHOUGH EURO HAS
THE BEST SUPPORT FOR SNOW AS SURFACE WET BULB TEMPS FALL BELOW
FREEZING ALONG AND WEST OF U.S. 23 BY 00Z SATURDAY. EVEN DURING THE
EVENING...THE LOW LEVEL NORTHEAST WINDS OF LAKE HURON LOOK TO KEEP
EASTERN HALF OF THE CWA ABOVE FREEZING. THROW IN THE FACT THE GFS IS
STRONGER/MILDER AND FARTHER WEST (ALTHOUGH PREFERENCE IS WITH
EURO/CANADIAN SOLUTIONS)...AND WILL SKEW THE FORECAST ON THE WET
SIDE FOR MOST OF FRIDAY...WITH STILL SOME SNOW MIXING IN/CHANGING
OVER TOWARD SUNSET...AS 850 MB TEMPS FALL INTO THE -8 TO -10 C
RANGE. BETTER CHANCE OF ACCUMULATING SNOW SHOWERS FRIDAY NIGHT AS
LAKE EFFECT LIKELY PERSISTS AND LOW LEVEL COLDER AIR CONTINUES TO
BLEED IN UNDER NIGHT-TIME SETTING. EXTENSION OF THE IRISH
HILLS/HIGHER TERRAIN THE FAVORED LOCATIONS FOR LIGHT SNOW
ACCUMULATIONS.

SATURDAY IS A TRICKY FORECAST AS WELL...AS WE WILL BE ON THE WESTERN
EDGE OF THE LARGE UPPER LEVEL CIRCULATION. WITH LOW LEVEL FLOW STILL
OUT OF THE NORTHEAST...AND COLD AIRMASS (NEGATIVE MID TO UPPER
SINGLES AT 850 MB)...LIKELY WILL SEE ADDITIONAL SCATTERED SNOW/RAIN
SHOWERS AROUND...ESPECIALLY DURING MORNING HOURS.

MARINE...

SOUTHWEST WINDS OF 15 TO 25 KNOTS TODAY WILL GRADUALLY EASE AND
SHIFT TO THE NORTHWEST TONIGHT...BECOMING LIGHT ON THURSDAY. THIS
LULL IN THE WINDS WILL BE SHORT LIVED...AS AN ARCTIC FRONT PASSES
THROUGH THE CENTRAL GREAT LAKES ON FRIDAY. NORTHERLY GUSTS TO GALES
APPEAR LIKELY FRIDAY AFTERNOON INTO FRIDAY NIGHT OVER THE SOUTHERN
TWO THIRDS OF LAKE HURON DURING THIS TIME WITH SIGNIFICANT WAVE
HEIGHTS OF 5 TO 10 FEET OVER SOUTHERN LAKE HURON. HAVE GONE AHEAD
AND ISSUED GALE WATCHES WITH THIS FORECAST PACKAGE. ALTHOUGH WINDS
WILL GRADUALLY DIMINISH ON SATURDAY...THE NORTHEAST WIND DIRECTION
WILL MAINTAIN HIGHER WAVES ALONG NEARSHORE WATERS. HIGH PRESSURE
BUILDING IN ON SUNDAY WILL ASSURE LIGHT WINDS.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ463-464.

     SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR LHZ421-441.

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

$$

AVIATION.....KURIMSKI
SHORT TERM...KURIMSKI
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 290752
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
352 AM EDT WED OCT 29 2014

.SHORT TERM...TODAY AND TONIGHT

DESPITE THE PASSAGE OF A COLD FRONT YESTERDAY...COLD AIR ADVECTION
WILL CONTINUE TODAY AS A LOW LEVEL TROUGH TURNS 850 MB WINDS FROM A
WESTERLY TO A NORTHWESTERLY DIRECTION...FURTHER DROPPING 850 MB
TEMPERATURES INTO THE SINGLE DIGITS BELOW ZERO. SKIES THIS MORNING
WILL START OUT AS PARTLY TO MOSTLY CLOUDY...DEPENDING ON LOCATION AS
THERE ARE CURRENTLY SEVERAL BREAKS IN THE CLOUDS. SKIES SHOULD
QUICKLY BECOME BROKEN TO OVERCAST LATER THIS MORNING AS COLD AIR
ALOFT...LINGERING 850 MB MOISTURE AND CONTINUED CYCLONIC FLOW CREATE
CONDITIONS CONDUCIVE FOR A PRETTY SOLID DECK OF STRATOCUMULUS TO
FORM. THE CONTINUED COLD AIR ADVECTION AND ABUNDANT CLOUD COVER WILL
SEVERELY LIMIT THE DIURNAL RANGE IN TEMPERATURES AS HIGHS ONLY TOP
OUT AROUND 50 DEGREES THIS AFTERNOON.

WITH THE LOSS OF DAYTIME HEATING THE DIURNALLY DRIVEN CLOUDS WILL
DISSIPATE AS DRIER AIR AND SURFACE RIDGING BUILD IN FROM
THE WEST. HOWEVER A COMPLETE CLEARING IS NOT EXPECTED AS 850 MB
MOISTURE REMAINS OVER THE CENTRAL GREAT LAKES WITH NORTHWEST FLOW
ALOFT. THE AFOREMENTIONED RIDGING WILL CAUSE SURFACE WINDS TO
BECOME LIGHT...THIS COMBINED WITH SOME BREAKS IN THE CLOUDS WILL
CAUSE OVERNIGHT LOWS TO FALL INTO THE LOWER TO MIDDLE 30S ACROSS
SOUTHEAST MICHIGAN.

&&

.LONG TERM...

STRONG POLAR PV ANOMALY DESCENDING FROM THE NORTHWEST
TERRITORIES/NUNAVUT TODAY...AND DROPPING SOUTH THROUGH THE AREA ON
FRIDAY...DELIVERING THE FIRST SNOWFLAKES OF THE FALL SEASON TO
SOUTHEAST MICHIGAN. STILL NEED TO TO FINE TUNE EXACT TRACK OF
DEVELOPING 500 MB LOW CENTER WHICH WILL DICTATE SYNOPTIC SUPPORT OF
PRECIPITATION VS MESOSCALE LAKE EFFECT OFF LAKE HURON. A LOOKED AT
THE STANDARDIZED ANOMALIES OF 500 MB HEIGHTS AND 850 MB TEMPS DOES
NOT SHOW ANYTHING TERRIBLY UNUSUAL (-1.5)/NON-RECORD BREAKING...AND
THUS MAKING THIS A VERY DIFFICULT FORECAST IN DETERMINING WHAT IF
ANY SNOW ACCUMULATIONS WILL OCCUR. NEGATIVES FOR THE EVENT INCLUDE
THE UNFAVORABLE AFTERNOON TIMING...WARM MARINE LAYER/WATERS OF LAKE
HURON (LOWER 50S)...AND WARM GROUND (SOIL TEMPS 45-50). WILL BE
TRUSTING THE SURFACE/NEAR SURFACE PROFILES OF THE 00Z
NAM/EURO/CANADIAN...WHICH OBVIOUSLY ARE SUBJECT TO BE IN
ERROR/REVISED. THIS GUIDANCE SUGGEST SURFACE TEMPERATURES
REMAINING ABOVE FREEZING THROUGH 00Z SATURDAY...ALTHOUGH EURO HAS
THE BEST SUPPORT FOR SNOW AS SURFACE WET BULB TEMPS FALL BELOW
FREEZING ALONG AND WEST OF U.S. 23 BY 00Z SATURDAY. EVEN DURING THE
EVENING...THE LOW LEVEL NORTHEAST WINDS OF LAKE HURON LOOK TO KEEP
EASTERN HALF OF THE CWA ABOVE FREEZING. THROW IN THE FACT THE GFS IS
STRONGER/MILDER AND FARTHER WEST (ALTHOUGH PREFERENCE IS WITH
EURO/CANADIAN SOLUTIONS)...AND WILL SKEW THE FORECAST ON THE WET
SIDE FOR MOST OF FRIDAY...WITH STILL SOME SNOW MIXING IN/CHANGING
OVER TOWARD SUNSET...AS 850 MB TEMPS FALL INTO THE -8 TO -10 C
RANGE. BETTER CHANCE OF ACCUMULATING SNOW SHOWERS FRIDAY NIGHT AS
LAKE EFFECT LIKELY PERSISTS AND LOW LEVEL COLDER AIR CONTINUES TO
BLEED IN UNDER NIGHT-TIME SETTING. EXTENSION OF THE IRISH
HILLS/HIGHER TERRAIN THE FAVORED LOCATIONS FOR LIGHT SNOW
ACCUMULATIONS.

SATURDAY IS A TRICKY FORECAST AS WELL...AS WE WILL BE ON THE WESTERN
EDGE OF THE LARGE UPPER LEVEL CIRCULATION. WITH LOW LEVEL FLOW STILL
OUT OF THE NORTHEAST...AND COLD AIRMASS (NEGATIVE MID TO UPPER
SINGLES AT 850 MB)...LIKELY WILL SEE ADDITIONAL SCATTERED SNOW/RAIN
SHOWERS AROUND...ESPECIALLY DURING MORNING HOURS.

&&

.MARINE...

SOUTHWEST WINDS OF 15 TO 25 KNOTS TODAY WILL GRADUALLY EASE AND
SHIFT TO THE NORTHWEST TONIGHT...BECOMING LIGHT ON THURSDAY. THIS
LULL IN THE WINDS WILL BE SHORT LIVED...AS AN ARCTIC FRONT PASSES
THROUGH THE CENTRAL GREAT LAKES ON FRIDAY. NORTHERLY GUSTS TO GALES
APPEAR LIKELY FRIDAY AFTERNOON INTO FRIDAY NIGHT OVER THE SOUTHERN
TWO THIRDS OF LAKE HURON DURING THIS TIME WITH SIGNIFICANT WAVE
HEIGHTS OF 5 TO 10 FEET OVER SOUTHERN LAKE HURON. HAVE GONE AHEAD
AND ISSUED GALE WATCHES WITH THIS FORECAST PACKAGE. ALTHOUGH WINDS
WILL GRADUALLY DIMINISH ON SATURDAY...THE NORTHEAST WIND DIRECTION
WILL MAINTAIN HIGHER WAVES ALONG NEARSHORE WATERS. HIGH PRESSURE
BUILDING IN ON SUNDAY WILL ASSURE LIGHT WINDS.

&&

.AVIATION...ISSUED 1202 AM EDT WED OCT 29 2014

//DISCUSSION...

OBSERVATIONS MOSTLY SUPPORT INCOMING MODEL DATA THAT SHOWS THE WIND
REMAINING DECOUPLED DURING THE NIGHT. A STRAY GUST TO 20 KNOTS WILL
BECOME INCREASINGLY POSSIBLE AS COLDER AIR CONTINUES TO SETTLE OVER
THE REGION AND THEN EASILY REACHABLE DURING THE DAY AS GROUND
HEATING INTERACTS WITH THE CORE OF THE COLD AIR MASS. PATCHES OF
STRATOCU DURING THE NIGHT WILL INCREASE IN COVERAGE THROUGHOUT THE
DAY BUT CEILING IS EXPECTED TO REMAIN VFR THROUGH WEDNESDAY EVENING.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE ON CEILING BELOW 5000 FT DURING THE DAY.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...GALE WATCH FROM FRIDAY MORNING THROUGH SATURDAY MORNING FOR LHZ362-
     363-421-441-462.

     GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR
     LHZ442-443-463-464.

     SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR LHZ421-441.

     SMALL CRAFT ADVISORY UNTIL 8 AM EDT THIS MORNING FOR LHZ422.

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

$$

SHORT TERM...KURIMSKI
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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