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000
FXUS63 KDTX 170753
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
353 AM EDT THU APR 17 2014

.SHORT TERM... TODAY AND TONIGHT

EARLY MORNING OBSERVATIONS INDICATE THE DAY STARTING OUT WITH
TEMPERATURES IN THE 30S...MILD COMPARED TO RECENT DAYS...BUT WITH A
STEADY SOUTHEAST WIND ADDING A CHILL TO THE AIR. THE WIND AND BROKEN
HIGH CLOUD COVERAGE WILL BE THE ONLY EVIDENCE OF THE LOW PRESSURE
SYSTEM MOVING INTO WISCONSIN DURING THE MORNING WHICH WILL WEAKEN
WHILE MOVING TOWARD THE STRAITS AREA TODAY. THE MAIN CHALLENGE IN
THE FORECAST WILL BE THE DETERMINATION OF MAX TEMPS WITHIN LOW LEVEL
THICKNESS WARMING BUT WITH CONSIDERABLE HIGH CLOUD COVER AND A
LINGERING EASTERLY COMPONENT IN THE SURFACE WIND. THE WEAKENING
TREND IN THE WISCONSIN LOW WILL BE FORCED WITH GOOD CONFIDENCE BY
LARGER SCALE UPPER LEVEL HEIGHT FALLS OVER THE PLAINS ASSOCIATED
WITH THE NEXT SYSTEM. THE RESULTING WEAKER SURFACE GRADIENT FLOW
OVER LOWER MICHIGAN WILL PRESERVE THE EASTERLY COMPONENT IN THE WIND
FIELD WHICH STRONGLY SUPPORTS THE COOL END OF THE TEMPERATURE
GUIDANCE SPECTRUM. EXPECT MAX TEMPS TO REACH THE UPPER 50S
INTERIOR...LOWER TO MID 50S CLOSER TO THE LAKES...AND READINGS
OPTIMISTICALLY FORECAST TO REACH THE MID 40S NEAR THE LAKE HURON
SHORELINE LATE IN THE DAY.

THE SHORT WAVE OVER THE SOUTHERN PLAINS DURING THE MORNING...
COMBINED WITH THE NEXT SURGE OF UPPER LEVEL JET ENERGY THROUGH THE
ROCKIES...WILL LEAD TO NEARLY FULL LATITUDE THROUGH DEVELOPMENT OVER
THE CENTRAL STATES BY TONIGHT. THE RESULTING INCREASED SOUTHWEST
FLOW ALOFT AS THE UPPER JET MOVES OVERHEAD WILL HELP STRENGTHEN THE
FRONTAL ZONE TRAILING THE STRAITS SYSTEM OVER LOWER MICHIGAN. MODEL
CROSS SECTIONS THROUGH THE FRONTAL ZONE INDICATE INSTABILITY WITHIN
THE LOW LEVEL THETA-E RIDGE WITH ADEQUATE MOISTURE SUPPLY. GIVEN THE
WARM NATURE OF THE SYSTEM...SPECIFIC HUMIDITY OF 3-4 G/KG AND 850 MB
DEWPOINT STRUGGLING TO RISE ABOVE 1-2C IS JUST OK AND SUGGESTS A
HIGH POP/LOW QPF SCENARIO. THE MODEST MOISTURE SUPPLY DEPICTED BY
THE MODELS LOOKS GOOD IN LIGHT OF SURFACE HIGH PRESSURE SPRAWLED
OVER THE ENTIRE ATLANTIC AND GULF COASTS FORCING SLOW DEVELOPMENT OF
GULF MODIFIED RETURN FLOW IN THE LOW LEVELS. THE INHERITED LIKELY
POP FORECAST FOR TONIGHT WILL BE MAINTAINED BUT NUDGED FARTHER BACK
IN TIME TO ALLOW FOR SATURATION OF THE LOW LEVELS BY MIDNIGHT.
EXPECT TEMPERATURES TO REMAIN EASILY ABOVE FREEZING THROUGH THE
NIGHT. MIN TEMPS IN THE UPPER 30S TO LOWER 40S LOOK GOOD BY SUNRISE
FRIDAY.

&&

.LONG TERM...

PROGRESSIVE PATTERN WITH STORM TRACK PREDOMINATELY NORTH OF THE
REGION DURING THE EXTENDED PERIOD...SETTING US FOR WARMER
TEMPERATURES.

UPPER LEVEL TROUGH TO SWING THROUGH THE CENTRAL GREAT LAKES DURING
FRIDAY...WITH SURFACE COLD FRONT LIKELY CLEARING THE STATE AROUND
NOON...PER LATEST TRENDS. THIS FASTER TIMING....AND DISPLACEMENT
WITH THE SOUTHERN STREAM/MOISTURE DOES NOT GIVE ONE A LOT OF
CONFIDENCE IN SHOWERS...AND CERTAINLY NOT DURING THE AFTERNOON HOURS
WHERE WE WILL CUT BACK DRAMATICALLY ON POPS. STRONGLY CONFLUENT
UPPER LEVEL NORTHWEST FLOW FRIDAY EVENING/NIGHT WILL LEAD TO GOOD
SUBSIDENCE AND SURFACE HIGH BUILDING IN...LEADING TO ANOTHER COLD
NIGHT ACROSS SOUTHEAST MICHIGAN. THUMB REGION LOOKS TO BE DROPPING
INTO THE 20S WITH LOWER 30S ELSEWHERE...PER LATEST GUIDANCE.

UPPER LEVEL RIDGE AND SPRAWLING HIGH PRESSURE WILL DOMINATE DURING
SATURDAY. LIGHT EAST-SOUTHEAST FLOW DEVELOPING WILL ATTEMPT TO LIMIT
THE TEMPERATURE CLIMB...BUT TEMPS SHOULD BE ABLE TO SNEAK INTO THE
LOW TO MID 50S WITH MID APRIL INSOLATION.

500 MB LOW EXITING MONTANA AND TRACKING NORTHEAST...INTO ONTARIO ON
SUNDAY. MINIMAL HEIGHT FALLS OVER THE SOUTHERN GREAT LAKES
REGION...AND COLD FRONT WILL BECOME NEARLY PARALLEL TO THE MEAN
FLOW...WHICH SHOULD ALLOW FOR A NICE DAY ON SUNDAY (LOW CHANCE OF
RAIN SHOWERS FAR NORTH)...AS SOUTHWEST FLOW ADVECTS MILDER AIR INTO
THE REGION. 850 MB TEMPS RISE INTO THE HIGH SINGLE NUMBERS. MAXES
CLIMBING WELL INTO THE 60S ARE EXPECTED...WITH 70 DEGREES WITHIN
REACH ACROSS SOUTHERN AREAS IF SKIES END UP MOSTLY SUNNY.

&&

.MARINE...

A WEAKENING LOW APPROACHING THE CENTRAL GREAT LAKES TODAY WILL
DISSIPATE TONIGHT...BUT COLD FRONT WILL PRODUCE A FEW SHOWERS AS IT
TRACKS THROUGH THE REGION FRIDAY MORNING. SOUTHEAST WINDS OF 15 TO
20 KNOTS WILL BECOME LIGHT WESTERLY POST FRONTAL. SPRAWLING HIGH
PRESSURE WILL THEN BUILD INTO THE AREA LATE FRIDAY INTO
SATURDAY...LEADING TO LIGHT WINDS. SOUTHERLY WINDS WILL PICK UP FOR
THE SECOND HALF OF THE WEEKEND...BUT REMAINING UNDER 20 KNOTS ACROSS
MOST AREAS.

&&

.AVIATION...ISSUED 1200 AM EDT THU APR 17 2014

//DISCUSSION...

A VERY DRY LOW LEVEL ENVIRONMENT WILL MAINTAIN VFR CONDITIONS
TONIGHT AND THURSDAY.  WINDS WILL FIRMLY HOLD OUT OF THE
EAST-SOUTHEAST AS THE AREA REMAINS BETWEEN EXITING HIGH PRESSURE
AND THE NEXT LOW PRESSURE SYSTEM LIFTING TOWARD THE UPPER
PENINSULA.  SLIGHT INCREASE IN SPEEDS ON THURSDAY AS THE GRADIENT
STRENGTHENS IN ADVANCE OF THE ASSOCIATED COLD FRONT.  THIS FRONTAL
BOUNDARY WILL EASE INTO THE REGION THURSDAY NIGHT.  WINDS BEGIN TO
VEER TOWARD SOUTHERLY UPON THE ARRIVAL TOWARD EVENING.  AN
ACCOMPANYING THICKENING/LOWERING OF CLOUDS THROUGH THIS TIME.

//DTW THRESHOLD THREATS...

* NONE

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

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


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









000
FXUS63 KDTX 170400
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1200 AM EDT THU APR 17 2014

.AVIATION...

//DISCUSSION...

A VERY DRY LOW LEVEL ENVIRONMENT WILL MAINTAIN VFR CONDITIONS
TONIGHT AND THURSDAY.  WINDS WILL FIRMLY HOLD OUT OF THE
EAST-SOUTHEAST AS THE AREA REMAINS BETWEEN EXITING HIGH PRESSURE
AND THE NEXT LOW PRESSURE SYSTEM LIFTING TOWARD THE UPPER
PENINSULA.  SLIGHT INCREASE IN SPEEDS ON THURSDAY AS THE GRADIENT
STRENGTHENS IN ADVANCE OF THE ASSOCIATED COLD FRONT.  THIS FRONTAL
BOUNDARY WILL EASE INTO THE REGION THURSDAY NIGHT.  WINDS BEGIN TO
VEER TOWARD SOUTHERLY UPON THE ARRIVAL TOWARD EVENING.  AN
ACCOMPANYING THICKENING/LOWERING OF CLOUDS THROUGH THIS TIME.

//DTW THRESHOLD THREATS...

* NONE

&&

.PREV DISCUSSION...ISSUED 319 PM EDT WED APR 16 2014

SHORT TERM... TONIGHT

THE REGION OF SNOW NOW EXTENDING ACROSS PORTIONS OF MN/NRN WI/WRN
UPPER MI IS ASSOCIATED WITH A COMPACT MID LEVEL WAVE ROTATING INTO
THE UPPER MIDWEST. THE SFC LOW LOCATED OVER THE NE/IA BORDER WILL
LIFT INTO WRN WISCONSIN BY THURS MORNING AS THE MID LEVEL WAVE LIFTS
UP TOWARD WRN UPPER MI. THE OVERALL TREND WITH THIS SYSTEM THROUGH
THE NIGHT WILL BE FOR GRADUAL WEAKENING AS THE MID LEVEL WAVE
DAMPENS. SOME RADAR RETURNS WITHIN A MID CLOUD DECK HAVE BEEN
ADVANCING ACROSS W-CNTL LOWER MI THIS AFTERNOON. A REGION OF WEAK
ASCENT ALONG THE 285-295K SURFACES IN ADVANCE OF THE MID LEVEL WAVE
IS RESPONSIBLE FOR THESE RETURNS. THUS FAR NO PRECIP HAS BEEN
REPORTED OVER LOWER MI AS A DEPARTING LOW LEVEL ANTICYCLONE IS
SUSTAINING A HEALTHY AMOUNT OF LOW LEVEL DRY AIR. THE ISENTROPIC
ASCENT WILL LARGELY PASS NORTH OF THE TRI CITIES THIS EVENING. A
BROAD REGION OF LOW LEVEL WARM AIR ADVECTION ASSOCIATED WITH THIS
SYSTEM WILL OVERSPREAD SE MI TONIGHT. STRENGTHENING LOW LEVEL SE
FLOW DURING THE NIGHT WILL ACTUALLY SUSTAIN A GOOD DEGREE OF DRY AIR
IN THE LOW LEVELS WHICH WILL KEEP SE MI PRECIP FREE. DESPITE THE
COOL AFTERNOON TEMPS AND VERY LOW SFC DEWPOINTS /IN THE TEENS
ATTM/... THE INCREASING GRADIENT OVERNIGHT /950MB WINDS FORECAST TO
RISE TO 35 KTS/ WILL HINDER THE AMOUNT OF BOUNDARY LAYER DECOUPLING.
THIS REMAINS SUPPORTIVE OF CURRENT FORECAST MIN TEMPS ON THE HIGH
SIDE OF GUIDANCE...MAINLY IN THE LOW 30S.

LONG TERM...THURSDAY THROUGH WEDNESDAY

HIGH PRESSURE WILL SLIDE OFF TO THE EAST AS A WEAKENING LOW PRESSURE
SYSTEM TRACKS ACROSS NORTHERN MICHIGAN. PRECIPITATION ASSOCIATED
WITH THIS LOW WILL REMAIN NORTH OF THE CWA...HOWEVER EXPECT CLOUDS
TO INCREASE OVER SOUTHEAST MICHIGAN ESPECIALLY NORTH OF I-69. AS A
RESULT OF THE INCREASED CLOUD COVER THROUGH THURSDAY...HAVE LOWERED
TEMPS A COUPLE DEGREES /HIGHS EXPECTED IN THE MID TO UPPER 50S/.

A FRONTAL BOUNDARY STILL LOOKS TO IMPACT SOUTHEAST MICHIGAN ON
THURSDAY NIGHT AND INTENSIFY INTO FRIDAY AS A THETA E BOUNDARY
SLIDES ACROSS THE REGION. THIS FRONT WILL BRING RAIN SHOWERS FOR
THURSDAY NIGHT AND FRIDAY. CURRENT MODEL RUNS ARE SHOWING
CONSISTENCY ABOUT THE TIMING OF THIS FRONT AND THEREFORE HAVE BUMPED
POPS UP TO LIKELY FROM THURSDAY NIGHT THROUGH FRIDAY. HIGH
TEMPERATURES ON FRIDAY WILL BE WELL INTO THE MID 50S HOWEVER...COLD
AIR FILTERS IN BEHIND THE FRONTAL PASSAGE. 850 MB TEMPERATURES SHOW
TEMPERATURES DROPPING TEMPERATURES INTO THE 0 C TO -4 C RESULTING IN
SURFACE TEMPERATURES IN THE MID TO LOW 30S ON FRIDAY NIGHT. THE
MAJORITY OF THE PRECIPITATION IS ANTICIPATED TO MOVE OUT OF THE
REGION BY 00Z SATURDAY...BUT ANY LINGERING SHOWERS PRESENT INTO
FRIDAY NIGHT COULD BE A RAIN/SNOW MIX AS THE TEMPERATURES DROP.

SATURDAY WILL BRING A RAPID INCREASE IN H85 TEMPS FROM -2 TO +6 AS
STRONG WAA SETS UP FROM RETURN FLOW. AS HIGH PRESSURE DEPARTS TO THE
EAST...A FRONTAL BOUNDARY AND ELONGATED LOW PRESSURE TROUGH WILL
CROSS THE AREA ON SUNDAY. THE NARROW FRONTAL ZONE AND SURROUNDING DRY
AIR WILL KEEP SHOWERS SPOTTY FOR THE DAY. COLD AIR ADVECTION WILL
ENSUE FOR NEXT WEEK WITH MAINLY DRY CONDITIONS.

MARINE...

HIGH PRESSURE SLIDES EAST TONIGHT AS LOW PRESSURE ENTERS THE WESTERN
GREAT LAKES. WINDS ARE EXPECTED TO REMAIN BELOW 30 KNOTS TONIGHT AND
THURSDAY AS THIS LOW BUILDS OVER THE EASTERN GREAT LAKES. LIGHTER
WINDS WILL RETURN THURSDAY NIGHT INTO FRIDAY AS A COLD FRONT SLOWLY
MOVES THROUGH THE AREA...BRINGING WITH IT A CHANCE OF RAIN AND
POSSIBLY SOME SNOW SHOWERS OVER NORTHERN LAKE HURON. HIGH PRESSURE
RETURNS FOR SATURDAY BEFORE THE NEXT DISTURBANCE IMPACTS THE
NORTHERN GREAT LAKES ON SUNDAY.

&&

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

&&

$$

AVIATION.....MR
SHORT TERM...SC
LONG TERM....RK/MM
MARINE.......RK

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






000
FXUS63 KDTX 162314
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
714 PM EDT WED APR 16 2014


.AVIATION...

//DISCUSSION...

A VERY DRY LOW LEVEL ENVIRONMENT WILL MAINTAIN VFR CONDITIONS
THROUGH THURSDAY.  WINDS WILL FIRMLY HOLD OUT OF THE SOUTHEAST AS
SE MICHIGAN REMAINS BETWEEN EXITING HIGH PRESSURE AND THE NEXT LOW
PRESSURE SYSTEM LIFTING TOWARD THE UPPER PENINSULA.  SLIGHT INCREASE
IN SPEEDS ON THURSDAY AS THE GRADIENT STRENGTHENS IN ADVANCE OF THE
ASSOCIATED COLD FRONT.  THIS FRONTAL BOUNDARY WILL EASE INTO THE
REGION THURSDAY NIGHT.

//DTW THRESHOLD THREATS...

* NONE

&&

.PREV DISCUSSION...ISSUED 319 PM EDT WED APR 16 2014

SHORT TERM... TONIGHT

THE REGION OF SNOW NOW EXTENDING ACROSS PORTIONS OF MN/NRN WI/WRN
UPPER MI IS ASSOCIATED WITH A COMPACT MID LEVEL WAVE ROTATING INTO
THE UPPER MIDWEST. THE SFC LOW LOCATED OVER THE NE/IA BORDER WILL
LIFT INTO WRN WISCONSIN BY THURS MORNING AS THE MID LEVEL WAVE LIFTS
UP TOWARD WRN UPPER MI. THE OVERALL TREND WITH THIS SYSTEM THROUGH
THE NIGHT WILL BE FOR GRADUAL WEAKENING AS THE MID LEVEL WAVE
DAMPENS. SOME RADAR RETURNS WITHIN A MID CLOUD DECK HAVE BEEN
ADVANCING ACROSS W-CNTL LOWER MI THIS AFTERNOON. A REGION OF WEAK
ASCENT ALONG THE 285-295K SURFACES IN ADVANCE OF THE MID LEVEL WAVE
IS RESPONSIBLE FOR THESE RETURNS. THUS FAR NO PRECIP HAS BEEN
REPORTED OVER LOWER MI AS A DEPARTING LOW LEVEL ANTICYCLONE IS
SUSTAINING A HEALTHY AMOUNT OF LOW LEVEL DRY AIR. THE ISENTROPIC
ASCENT WILL LARGELY PASS NORTH OF THE TRI CITIES THIS EVENING. A
BROAD REGION OF LOW LEVEL WARM AIR ADVECTION ASSOCIATED WITH THIS
SYSTEM WILL OVERSPREAD SE MI TONIGHT. STRENGTHENING LOW LEVEL SE
FLOW DURING THE NIGHT WILL ACTUALLY SUSTAIN A GOOD DEGREE OF DRY AIR
IN THE LOW LEVELS WHICH WILL KEEP SE MI PRECIP FREE. DESPITE THE
COOL AFTERNOON TEMPS AND VERY LOW SFC DEWPOINTS /IN THE TEENS
ATTM/... THE INCREASING GRADIENT OVERNIGHT /950MB WINDS FORECAST TO
RISE TO 35 KTS/ WILL HINDER THE AMOUNT OF BOUNDARY LAYER DECOUPLING.
THIS REMAINS SUPPORTIVE OF CURRENT FORECAST MIN TEMPS ON THE HIGH
SIDE OF GUIDANCE...MAINLY IN THE LOW 30S.

LONG TERM...THURSDAY THROUGH WEDNESDAY

HIGH PRESSURE WILL SLIDE OFF TO THE EAST AS A WEAKENING LOW PRESSURE
SYSTEM TRACKS ACROSS NORTHERN MICHIGAN. PRECIPITATION ASSOCIATED
WITH THIS LOW WILL REMAIN NORTH OF THE CWA...HOWEVER EXPECT CLOUDS
TO INCREASE OVER SOUTHEAST MICHIGAN ESPECIALLY NORTH OF I-69. AS A
RESULT OF THE INCREASED CLOUD COVER THROUGH THURSDAY...HAVE LOWERED
TEMPS A COUPLE DEGREES /HIGHS EXPECTED IN THE MID TO UPPER 50S/.

A FRONTAL BOUNDARY STILL LOOKS TO IMPACT SOUTHEAST MICHIGAN ON
THURSDAY NIGHT AND INTENSIFY INTO FRIDAY AS A THETA E BOUNDARY
SLIDES ACROSS THE REGION. THIS FRONT WILL BRING RAIN SHOWERS FOR
THURSDAY NIGHT AND FRIDAY. CURRENT MODEL RUNS ARE SHOWING
CONSISTENCY ABOUT THE TIMING OF THIS FRONT AND THEREFORE HAVE BUMPED
POPS UP TO LIKELY FROM THURSDAY NIGHT THROUGH FRIDAY. HIGH
TEMPERATURES ON FRIDAY WILL BE WELL INTO THE MID 50S HOWEVER...COLD
AIR FILTERS IN BEHIND THE FRONTAL PASSAGE. 850 MB TEMPERATURES SHOW
TEMPERATURES DROPPING TEMPERATURES INTO THE 0 C TO -4 C RESULTING IN
SURFACE TEMPERATURES IN THE MID TO LOW 30S ON FRIDAY NIGHT. THE
MAJORITY OF THE PRECIPITATION IS ANTICIPATED TO MOVE OUT OF THE
REGION BY 00Z SATURDAY...BUT ANY LINGERING SHOWERS PRESENT INTO
FRIDAY NIGHT COULD BE A RAIN/SNOW MIX AS THE TEMPERATURES DROP.

SATURDAY WILL BRING A RAPID INCREASE IN H85 TEMPS FROM -2 TO +6 AS
STRONG WAA SETS UP FROM RETURN FLOW. AS HIGH PRESSURE DEPARTS TO THE
EAST...A FRONTAL BOUNDARY AND ELONGATED LOW PRESSURE TROUGH WILL
CROSS THE AREA ON SUNDAY. THE NARROW FRONTAL ZONE AND SURROUNDING DRY
AIR WILL KEEP SHOWERS SPOTTY FOR THE DAY. COLD AIR ADVECTION WILL
ENSUE FOR NEXT WEEK WITH MAINLY DRY CONDITIONS.

MARINE...

HIGH PRESSURE SLIDES EAST TONIGHT AS LOW PRESSURE ENTERS THE WESTERN
GREAT LAKES. WINDS ARE EXPECTED TO REMAIN BELOW 30 KNOTS TONIGHT AND
THURSDAY AS THIS LOW BUILDS OVER THE EASTERN GREAT LAKES. LIGHTER
WINDS WILL RETURN THURSDAY NIGHT INTO FRIDAY AS A COLD FRONT SLOWLY
MOVES THROUGH THE AREA...BRINGING WITH IT A CHANCE OF RAIN AND
POSSIBLY SOME SNOW SHOWERS OVER NORTHERN LAKE HURON. HIGH PRESSURE
RETURNS FOR SATURDAY BEFORE THE NEXT DISTURBANCE IMPACTS THE
NORTHERN GREAT LAKES ON SUNDAY.

&&

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

&&

$$

AVIATION.....MR
SHORT TERM...SC
LONG TERM....RK/MM
MARINE.......RK

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






000
FXUS63 KDTX 161919
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
319 PM EDT WED APR 16 2014

.SHORT TERM... TONIGHT

THE REGION OF SNOW NOW EXTENDING ACROSS PORTIONS OF MN/NRN WI/WRN
UPPER MI IS ASSOCIATED WITH A COMPACT MID LEVEL WAVE ROTATING INTO
THE UPPER MIDWEST. THE SFC LOW LOCATED OVER THE NE/IA BORDER WILL
LIFT INTO WRN WISCONSIN BY THURS MORNING AS THE MID LEVEL WAVE LIFTS
UP TOWARD WRN UPPER MI. THE OVERALL TREND WITH THIS SYSTEM THROUGH
THE NIGHT WILL BE FOR GRADUAL WEAKENING AS THE MID LEVEL WAVE
DAMPENS. SOME RADAR RETURNS WITHIN A MID CLOUD DECK HAVE BEEN
ADVANCING ACROSS W-CNTL LOWER MI THIS AFTERNOON. A REGION OF WEAK
ASCENT ALONG THE 285-295K SURFACES IN ADVANCE OF THE MID LEVEL WAVE
IS RESPONSIBLE FOR THESE RETURNS. THUS FAR NO PRECIP HAS BEEN
REPORTED OVER LOWER MI AS A DEPARTING LOW LEVEL ANTICYCLONE IS
SUSTAINING A HEALTHY AMOUNT OF LOW LEVEL DRY AIR. THE ISENTROPIC
ASCENT WILL LARGELY PASS NORTH OF THE TRI CITIES THIS EVENING. A
BROAD REGION OF LOW LEVEL WARM AIR ADVECTION ASSOCIATED WITH THIS
SYSTEM WILL OVERSPREAD SE MI TONIGHT. STRENGTHENING LOW LEVEL SE
FLOW DURING THE NIGHT WILL ACTUALLY SUSTAIN A GOOD DEGREE OF DRY AIR
IN THE LOW LEVELS WHICH WILL KEEP SE MI PRECIP FREE. DESPITE THE
COOL AFTERNOON TEMPS AND VERY LOW SFC DEWPOINTS /IN THE TEENS
ATTM/... THE INCREASING GRADIENT OVERNIGHT /950MB WINDS FORECAST TO
RISE TO 35 KTS/ WILL HINDER THE AMOUNT OF BOUNDARY LAYER DECOUPLING.
THIS REMAINS SUPPORTIVE OF CURRENT FORECAST MIN TEMPS ON THE HIGH
SIDE OF GUIDANCE...MAINLY IN THE LOW 30S.

&&

.LONG TERM...THURSDAY THROUGH WEDNESDAY

HIGH PRESSURE WILL SLIDE OFF TO THE EAST AS A WEAKENING LOW PRESSURE
SYSTEM TRACKS ACROSS NORTHERN MICHIGAN. PRECIPITATION ASSOCIATED
WITH THIS LOW WILL REMAIN NORTH OF THE CWA...HOWEVER EXPECT CLOUDS
TO INCREASE OVER SOUTHEAST MICHIGAN ESPECIALLY NORTH OF I-69. AS A
RESULT OF THE INCREASED CLOUD COVER THROUGH THURSDAY...HAVE LOWERED
TEMPS A COUPLE DEGREES /HIGHS EXPECTED IN THE MID TO UPPER 50S/.

A FRONTAL BOUNDARY STILL LOOKS TO IMPACT SOUTHEAST MICHIGAN ON
THURSDAY NIGHT AND INTENSIFY INTO FRIDAY AS A THETA E BOUNDARY
SLIDES ACROSS THE REGION. THIS FRONT WILL BRING RAIN SHOWERS FOR
THURSDAY NIGHT AND FRIDAY. CURRENT MODEL RUNS ARE SHOWING
CONSISTENCY ABOUT THE TIMING OF THIS FRONT AND THEREFORE HAVE BUMPED
POPS UP TO LIKELY FROM THURSDAY NIGHT THROUGH FRIDAY. HIGH
TEMPERATURES ON FRIDAY WILL BE WELL INTO THE MID 50S HOWEVER...COLD
AIR FILTERS IN BEHIND THE FRONTAL PASSAGE. 850 MB TEMPERATURES SHOW
TEMPERATURES DROPPING TEMPERATURES INTO THE 0 C TO -4 C RESULTING IN
SURFACE TEMPERATURES IN THE MID TO LOW 30S ON FRIDAY NIGHT. THE
MAJORITY OF THE PRECIPITATION IS ANTICIPATED TO MOVE OUT OF THE
REGION BY 00Z SATURDAY...BUT ANY LINGERING SHOWERS PRESENT INTO
FRIDAY NIGHT COULD BE A RAIN/SNOW MIX AS THE TEMPERATURES DROP.

SATURDAY WILL BRING A RAPID INCREASE IN H85 TEMPS FROM -2 TO +6 AS
STRONG WAA SETS UP FROM RETURN FLOW. AS HIGH PRESSURE DEPARTS TO THE
EAST...A FRONTAL BOUNDARY AND ELONGATED LOW PRESSURE TROUGH WILL
CROSS THE AREA ON SUNDAY. THE NARROW FRONTAL ZONE AND SURROUNDING DRY
AIR WILL KEEP SHOWERS SPOTTY FOR THE DAY. COLD AIR ADVECTION WILL
ENSUE FOR NEXT WEEK WITH MAINLY DRY CONDITIONS.

&&

.MARINE...

HIGH PRESSURE SLIDES EAST TONIGHT AS LOW PRESSURE ENTERS THE WESTERN
GREAT LAKES. WINDS ARE EXPECTED TO REMAIN BELOW 30 KNOTS TONIGHT AND
THURSDAY AS THIS LOW BUILDS OVER THE EASTERN GREAT LAKES. LIGHTER
WINDS WILL RETURN THURSDAY NIGHT INTO FRIDAY AS A COLD FRONT SLOWLY
MOVES THROUGH THE AREA...BRINGING WITH IT A CHANCE OF RAIN AND
POSSIBLY SOME SNOW SHOWERS OVER NORTHERN LAKE HURON. HIGH PRESSURE
RETURNS FOR SATURDAY BEFORE THE NEXT DISTURBANCE IMPACTS THE
NORTHERN GREAT LAKES ON SUNDAY.

&&

.AVIATION...ISSUED 103 PM EDT WED APR 16 2014

//DISCUSSION...

VERY DRY AIR IN THE LOW LEVELS WILL PERSIST ACROSS SE MI THROUGH
THURS MORNING. THIS DRY AIR IS ASSOCIATED WITH SFC HIGH PRESSURE
WHICH WILL TRACK FROM THE ERN GREAT LAKES THIS AFTERNOON TO NRN NEW
ENGLAND BY THURS MORNING. THUS ANY PRECIP AND LOWER CLOUD COVER
ASSOCIATED WITH THE STORM SYSTEM NOW ROTATING ACROSS THE UPPER
MIDWEST WILL REMAIN WELL NORTHWEST OF THE SE MI TERMINALS. SO THE
ONLY AVIATION WEATHER RELATED ITEM OF INTEREST WILL BE A GRADUAL
BACKING OF THE S-SE WINDS TO THE EAST DURING THE COURSE OF THE
EVENING.

//DTW THRESHOLD THREATS...

* NONE

&&

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

&&

$$

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


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








000
FXUS63 KDTX 161703
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
103 PM EDT WED APR 16 2014


.AVIATION...

//DISCUSSION...

VERY DRY AIR IN THE LOW LEVELS WILL PERSIST ACROSS SE MI THROUGH
THURS MORNING. THIS DRY AIR IS ASSOCIATED WITH SFC HIGH PRESSURE
WHICH WILL TRACK FROM THE ERN GREAT LAKES THIS AFTERNOON TO NRN NEW
ENGLAND BY THURS MORNING. THUS ANY PRECIP AND LOWER CLOUD COVER
ASSOCIATED WITH THE STORM SYSTEM NOW ROTATING ACROSS THE UPPER
MIDWEST WILL REMAIN WELL NORTHWEST OF THE SE MI TERMINALS. SO THE
ONLY AVIATION WEATHER RELATED ITEM OF INTEREST WILL BE A GRADUAL
BACKING OF THE S-SE WINDS TO THE EAST DURING THE COURSE OF THE
EVENING.

//DTW THRESHOLD THREATS...

* NONE

&&

.PREV DISCUSSION...ISSUED 357 AM EDT WED APR 16 2014

SHORT TERM... TODAY AND TONIGHT

TODAY WILL START OUT WITH TEMPERATURES BOUNCING OFF NEAR RECORD LOWS
THANKS TO CLEAR SKY AND CALM WIND ASSOCIATED WITH HIGH PRESSURE
OVERHEAD. IT HELPS THAT DETROIT AND FLINT BROKE RECORD LOW MAX TEMPS
YESTERDAY AND SAGINAW WAS ONLY A DEGREE AWAY. NOCTURNAL RADIATIONAL
COOLING IS ALSO BOOSTED BY A COUPLE INCHES OF SNOW THAT MADE IT
THROUGH THE COLD AFTERNOON YESTERDAY...AT LEAST OUTSIDE OF THE
SAGINAW VALLEY AND NORTHERN THUMB. NEARLY FULL SUNSHINE THROUGH
THIN CIRRUS DURING THE MORNING WILL HELP READINGS REBOUND ABOVE
FREEZING BY NOON BEFORE THE HIGH CLOUDS THICKEN NOTICEABLY FOR THE
REST OF THE DAY. TEMPERATURE GUIDANCE IN THE LOWER TO MID 40S MAY
BE A BIT ON THE WARM SIDE INLAND BUT LOOK SUFFICIENTLY RESTRAINED
IN THE MID 30S NEAR LAKE HURON. DEPARTING HIGH PRESSURE AND THE
APPROACH OF THE NEXT LOW PRESSURE SYSTEM WILL FORCE A SE WIND OVER
THE REGION AND ONSHORE INTO THE THUMB.

SATELLITE IMAGERY DEPICTS THE EXPANSIVE COVERAGE OF HIGH CLOUDS WITH
THE PLAINS SYSTEM THAT WILL MOVE OVER SE MICHIGAN DURING THE DAY
AND PERSIST THROUGH THE EVENING. MODEL OUTPUT DEPICTS DEEP SYSTEM
RELATIVE ISENTROPIC ASCENT DEVELOPING OVER THE GREAT LAKES AHEAD
OF THE WAVE THAT WILL SUPPORT THE CLOUD FIELD AND SOME VIRGA BUT
HIGH CONDENSATION PRESSURE DEFICIT WILL FORCE PRECIPITATION TO
OUR NORTH. DRY AIR WILL ALSO BE REINFORCED BELOW 800 MB BY THE
SOUTHEAST FLOW ORIGINATING FROM THE SURFACE HIGH NEAR THE ATLANTIC
COAST BY THEN. THE LOW LEVEL GRADIENT FLOW...COMBINED WITH MOSTLY
OVERCAST MID AND HIGH CLOUDS...WILL MAINTAIN TEMPERATURES AT THE
HIGH END OF GUIDANCE. THIS IS WELL REPRESENTED IN THE GOING
FORECAST WITH MIN TEMPS AROUND THE FREEZING MARK BY SUNRISE
THURSDAY.

LONG TERM...

UPPER WAVE CURRENTLY WORKING THROUGH THE NORTHERN ROCKIES...ON TRACK
TO MOVE INTO THE WESTERN GREAT LAKES THURSDAY MORNING. THIS SYSTEM
WILL BE UNDERGOING DRAMATIC WEAKENING HOWEVER...IN FAVOR OF MORE
ROBUST UPSTREAM ENERGY...WHICH WILL BE WORKING THROUGH OUR AREA ON
FRIDAY.

BAROCLINIC ZONE WILL BE LOOSENING AND SURFACE LOW OPENING UP ON
THURSDAY AS IT PUSHES INTO THE CENTRAL GREAT LAKES LATE IN THE DAY.
LIGHT LOW LEVEL SOUTHERLY WINDS AND 850 MB TEMPS ADVERTISED TO RISE
TO 2.5 C SUPPORTING MAXES IN UPPER 50S TO NEAR 60 DEGREES.
AIRMASS IN PLACE LOOKS TO BE TOO DRY TO SUPPORT PRECIPITATION WITH
THE ISENTROPIC ASCENT DURING THE DAY. THE SLOW MOVING FRONTAL
BOUNDARY MAY YIELD DEVELOPING SHOWERS THURSDAY NIGHT WITH NARROW
THETA-E RIDGE AXIS...AS HEIGHT FALLS WITH THE NORTHERN STREAM
SHORTWAVE TROUGH ALSO ARRIVE. 00Z MODELS (GFS/EURO/CANADIAN/UKMET)
ALL IN AGREEMENT NOW WITH MORE PROGRESSIVE SYSTEM...WITH THE TROUGH
AXIS EAST OF SOUTHEAST MICHIGAN BY 00Z SATURDAY. STILL...GFS REMAINS
A HOLDOUT FOR A STRONGER...SOMEWHAT PHASED SYSTEM. PREFERENCE IS
WITH MAJORITY OF THE SOLUTIONS (NON-GFS)...AND WILL JUST CARRY
MODERATE CHANCE POPS DURING FRIDAY. WITH THE NORTHERN STREAM
TROUGH...THERE WILL BE SUFFICIENT COLD AIR COMING IN TO SUPPORT
SNOW...BUT PRECIPITATION WILL LIKELY HAVE SHUT OFF BY THE TIME THIS
OCCURS. STILL...850 MB TEMPS WILL SNEAK DOWN INTO THE LOW NEGATIVE
SINGLE NUMBERS SATURDAY MORNING...PRODUCING A CHILLY START TO THE
WEEKEND. HEIGHTS REBOUND QUICKLY WITH UPPER LEVEL RIDGE AXIS SLIDING
THROUGH OVER THE WEEKEND...WHICH SHOULD ALLOW FOR MAX TEMPS TO MAKE
A RUN TOWARD 60 DEGREES ON SUNDAY AHEAD OF THE NEXT COLD FRONT...AS
00Z EURO INDICATING 850 MB TEMPS RISING UP TO 8 C...WHICH WOULD
SUPPORT MUCH WARMER READINGS...BUT CLOUDS AND CHANCE OF RAIN SHOWERS
LEADS TO MORE CONSERVATIVE APPROACH AT THIS TIME.

MARINE...

HIGH PRESSURE OVER THE CENTRAL GREAT LAKES THIS MORNING WILL PROVIDE
LIGHT WINDS TODAY. SOUTHEAST WINDS WILL BE ON THE INCREASE THIS
EVENING...AS THE HIGH SLIDES EAST...BUT WINDS ARE EXPECTED TO REMAIN
BELOW 30 KNOTS TONIGHT. LONG FETCH WILL LEAD TO WAVES IN EXCESS OF 4
FEET OVER NORTHERN LAKE HURON...BUT NO SUCH CONCERNS OVER THE
NEARSHORE WATERS OF LAKE HURON. LIGHTER WINDS WILL RETURN THURSDAY
NIGHT INTO FRIDAY AS DIFFUSE COLD FRONT SLOWLY MOVES THROUGH THE
AREA...BRINGING WITH IT A CHANCE OF RAIN.

&&

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

&&

$$

AVIATION.....SC
SHORT TERM...BT
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 161107
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
707 AM EDT WED APR 16 2014

.AVIATION...

//DISCUSSION...

VFR CONDITIONS WILL BE IN PLACE TODAY THROUGH TONIGHT. LIGHT SOUTH
WIND WILL DEVELOP DURING THE MORNING AND BACK TOWARD THE SOUTHEAST
AS HIGH PRESSURE EXITS THE TERMINAL CORRIDOR. THE AREA WILL BECOME
IN BETWEEN THE DEPARTING HIGH AND THE NEXT LOW PRESSURE SYSTEM
MOVING THROUGH THE PLAINS. THIS SYSTEM WILL BRING THICKENING HIGH
CLOUDS AND WILL MAINTAIN MODEST SE WIND THROUGH TONIGHT. THERE MAY
BE SOME VIRGA INDICATED ON RADAR TONIGHT NEAR MBS BUT PRECIPITATION
REACHING THE GROUND WILL BE WELL INTO NORTHERN LOWER MICHIGAN.

//DTW THRESHOLD THREATS...

* NONE

&&

.PREV DISCUSSION...ISSUED 357 AM EDT WED APR 16 2014

SHORT TERM... TODAY AND TONIGHT

TODAY WILL START OUT WITH TEMPERATURES BOUNCING OFF NEAR RECORD LOWS
THANKS TO CLEAR SKY AND CALM WIND ASSOCIATED WITH HIGH PRESSURE
OVERHEAD. IT HELPS THAT DETROIT AND FLINT BROKE RECORD LOW MAX TEMPS
YESTERDAY AND SAGINAW WAS ONLY A DEGREE AWAY. NOCTURNAL RADIATIONAL
COOLING IS ALSO BOOSTED BY A COUPLE INCHES OF SNOW THAT MADE IT
THROUGH THE COLD AFTERNOON YESTERDAY...AT LEAST OUTSIDE OF THE
SAGINAW VALLEY AND NORTHERN THUMB. NEARLY FULL SUNSHINE THROUGH
THIN CIRRUS DURING THE MORNING WILL HELP READINGS REBOUND ABOVE
FREEZING BY NOON BEFORE THE HIGH CLOUDS THICKEN NOTICEABLY FOR THE
REST OF THE DAY. TEMPERATURE GUIDANCE IN THE LOWER TO MID 40S MAY
BE A BIT ON THE WARM SIDE INLAND BUT LOOK SUFFICIENTLY RESTRAINED
IN THE MID 30S NEAR LAKE HURON. DEPARTING HIGH PRESSURE AND THE
APPROACH OF THE NEXT LOW PRESSURE SYSTEM WILL FORCE A SE WIND OVER
THE REGION AND ONSHORE INTO THE THUMB.

SATELLITE IMAGERY DEPICTS THE EXPANSIVE COVERAGE OF HIGH CLOUDS WITH
THE PLAINS SYSTEM THAT WILL MOVE OVER SE MICHIGAN DURING THE DAY
AND PERSIST THROUGH THE EVENING. MODEL OUTPUT DEPICTS DEEP SYSTEM
RELATIVE ISENTROPIC ASCENT DEVELOPING OVER THE GREAT LAKES AHEAD
OF THE WAVE THAT WILL SUPPORT THE CLOUD FIELD AND SOME VIRGA BUT
HIGH CONDENSATION PRESSURE DEFICIT WILL FORCE PRECIPITATION TO
OUR NORTH. DRY AIR WILL ALSO BE REINFORCED BELOW 800 MB BY THE
SOUTHEAST FLOW ORIGINATING FROM THE SURFACE HIGH NEAR THE ATLANTIC
COAST BY THEN. THE LOW LEVEL GRADIENT FLOW...COMBINED WITH MOSTLY
OVERCAST MID AND HIGH CLOUDS...WILL MAINTAIN TEMPERATURES AT THE
HIGH END OF GUIDANCE. THIS IS WELL REPRESENTED IN THE GOING
FORECAST WITH MIN TEMPS AROUND THE FREEZING MARK BY SUNRISE
THURSDAY.

LONG TERM...

UPPER WAVE CURRENTLY WORKING THROUGH THE NORTHERN ROCKIES...ON TRACK
TO MOVE INTO THE WESTERN GREAT LAKES THURSDAY MORNING. THIS SYSTEM
WILL BE UNDERGOING DRAMATIC WEAKENING HOWEVER...IN FAVOR OF MORE
ROBUST UPSTREAM ENERGY...WHICH WILL BE WORKING THROUGH OUR AREA ON
FRIDAY.

BAROCLINIC ZONE WILL BE LOOSENING AND SURFACE LOW OPENING UP ON
THURSDAY AS IT PUSHES INTO THE CENTRAL GREAT LAKES LATE IN THE DAY.
LIGHT LOW LEVEL SOUTHERLY WINDS AND 850 MB TEMPS ADVERTISED TO RISE
TO 2.5 C SUPPORTING MAXES IN UPPER 50S TO NEAR 60 DEGREES.
AIRMASS IN PLACE LOOKS TO BE TOO DRY TO SUPPORT PRECIPITATION WITH
THE ISENTROPIC ASCENT DURING THE DAY. THE SLOW MOVING FRONTAL
BOUNDARY MAY YIELD DEVELOPING SHOWERS THURSDAY NIGHT WITH NARROW
THETA-E RIDGE AXIS...AS HEIGHT FALLS WITH THE NORTHERN STREAM
SHORTWAVE TROUGH ALSO ARRIVE. 00Z MODELS (GFS/EURO/CANADIAN/UKMET)
ALL IN AGREEMENT NOW WITH MORE PROGRESSIVE SYSTEM...WITH THE TROUGH
AXIS EAST OF SOUTHEAST MICHIGAN BY 00Z SATURDAY. STILL...GFS REMAINS
A HOLDOUT FOR A STRONGER...SOMEWHAT PHASED SYSTEM. PREFERENCE IS
WITH MAJORITY OF THE SOLUTIONS (NON-GFS)...AND WILL JUST CARRY
MODERATE CHANCE POPS DURING FRIDAY. WITH THE NORTHERN STREAM
TROUGH...THERE WILL BE SUFFICIENT COLD AIR COMING IN TO SUPPORT
SNOW...BUT PRECIPITATION WILL LIKELY HAVE SHUT OFF BY THE TIME THIS
OCCURS. STILL...850 MB TEMPS WILL SNEAK DOWN INTO THE LOW NEGATIVE
SINGLE NUMBERS SATURDAY MORNING...PRODUCING A CHILLY START TO THE
WEEKEND. HEIGHTS REBOUND QUICKLY WITH UPPER LEVEL RIDGE AXIS SLIDING
THROUGH OVER THE WEEKEND...WHICH SHOULD ALLOW FOR MAX TEMPS TO MAKE
A RUN TOWARD 60 DEGREES ON SUNDAY AHEAD OF THE NEXT COLD FRONT...AS
00Z EURO INDICATING 850 MB TEMPS RISING UP TO 8 C...WHICH WOULD
SUPPORT MUCH WARMER READINGS...BUT CLOUDS AND CHANCE OF RAIN SHOWERS
LEADS TO MORE CONSERVATIVE APPROACH AT THIS TIME.

MARINE...

HIGH PRESSURE OVER THE CENTRAL GREAT LAKES THIS MORNING WILL PROVIDE
LIGHT WINDS TODAY. SOUTHEAST WINDS WILL BE ON THE INCREASE THIS
EVENING...AS THE HIGH SLIDES EAST...BUT WINDS ARE EXPECTED TO REMAIN
BELOW 30 KNOTS TONIGHT. LONG FETCH WILL LEAD TO WAVES IN EXCESS OF 4
FEET OVER NORTHERN LAKE HURON...BUT NO SUCH CONCERNS OVER THE
NEARSHORE WATERS OF LAKE HURON. LIGHTER WINDS WILL RETURN THURSDAY
NIGHT INTO FRIDAY AS DIFFUSE COLD FRONT SLOWLY MOVES THROUGH THE
AREA...BRINGING WITH IT A CHANCE OF RAIN.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

AVIATION.....BT
SHORT TERM...BT
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 160757
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
357 AM EDT WED APR 16 2014

.SHORT TERM... TODAY AND TONIGHT

TODAY WILL START OUT WITH TEMPERATURES BOUNCING OFF NEAR RECORD LOWS
THANKS TO CLEAR SKY AND CALM WIND ASSOCIATED WITH HIGH PRESSURE
OVERHEAD. IT HELPS THAT DETROIT AND FLINT BROKE RECORD LOW MAX TEMPS
YESTERDAY AND SAGINAW WAS ONLY A DEGREE AWAY. NOCTURNAL RADIATIONAL
COOLING IS ALSO BOOSTED BY A COUPLE INCHES OF SNOW THAT MADE IT
THROUGH THE COLD AFTERNOON YESTERDAY...AT LEAST OUTSIDE OF THE
SAGINAW VALLEY AND NORTHERN THUMB. NEARLY FULL SUNSHINE THROUGH
THIN CIRRUS DURING THE MORNING WILL HELP READINGS REBOUND ABOVE
FREEZING BY NOON BEFORE THE HIGH CLOUDS THICKEN NOTICEABLY FOR THE
REST OF THE DAY. TEMPERATURE GUIDANCE IN THE LOWER TO MID 40S MAY
BE A BIT ON THE WARM SIDE INLAND BUT LOOK SUFFICIENTLY RESTRAINED
IN THE MID 30S NEAR LAKE HURON. DEPARTING HIGH PRESSURE AND THE
APPROACH OF THE NEXT LOW PRESSURE SYSTEM WILL FORCE A SE WIND OVER
THE REGION AND ONSHORE INTO THE THUMB.

SATELLITE IMAGERY DEPICTS THE EXPANSIVE COVERAGE OF HIGH CLOUDS WITH
THE PLAINS SYSTEM THAT WILL MOVE OVER SE MICHIGAN DURING THE DAY
AND PERSIST THROUGH THE EVENING. MODEL OUTPUT DEPICTS DEEP SYSTEM
RELATIVE ISENTROPIC ASCENT DEVELOPING OVER THE GREAT LAKES AHEAD
OF THE WAVE THAT WILL SUPPORT THE CLOUD FIELD AND SOME VIRGA BUT
HIGH CONDENSATION PRESSURE DEFICIT WILL FORCE PRECIPITATION TO
OUR NORTH. DRY AIR WILL ALSO BE REINFORCED BELOW 800 MB BY THE
SOUTHEAST FLOW ORIGINATING FROM THE SURFACE HIGH NEAR THE ATLANTIC
COAST BY THEN. THE LOW LEVEL GRADIENT FLOW...COMBINED WITH MOSTLY
OVERCAST MID AND HIGH CLOUDS...WILL MAINTAIN TEMPERATURES AT THE
HIGH END OF GUIDANCE. THIS IS WELL REPRESENTED IN THE GOING
FORECAST WITH MIN TEMPS AROUND THE FREEZING MARK BY SUNRISE
THURSDAY.

&&

.LONG TERM...

UPPER WAVE CURRENTLY WORKING THROUGH THE NORTHERN ROCKIES...ON TRACK
TO MOVE INTO THE WESTERN GREAT LAKES THURSDAY MORNING. THIS SYSTEM
WILL BE UNDERGOING DRAMATIC WEAKENING HOWEVER...IN FAVOR OF MORE
ROBUST UPSTREAM ENERGY...WHICH WILL BE WORKING THROUGH OUR AREA ON
FRIDAY.

BAROCLINIC ZONE WILL BE LOOSENING AND SURFACE LOW OPENING UP ON
THURSDAY AS IT PUSHES INTO THE CENTRAL GREAT LAKES LATE IN THE DAY.
LIGHT LOW LEVEL SOUTHERLY WINDS AND 850 MB TEMPS ADVERTISED TO RISE
TO 2.5 C SUPPORTING MAXES IN UPPER 50S TO NEAR 60 DEGREES.
AIRMASS IN PLACE LOOKS TO BE TOO DRY TO SUPPORT PRECIPITATION WITH
THE ISENTROPIC ASCENT DURING THE DAY. THE SLOW MOVING FRONTAL
BOUNDARY MAY YIELD DEVELOPING SHOWERS THURSDAY NIGHT WITH NARROW
THETA-E RIDGE AXIS...AS HEIGHT FALLS WITH THE NORTHERN STREAM
SHORTWAVE TROUGH ALSO ARRIVE. 00Z MODELS (GFS/EURO/CANADIAN/UKMET)
ALL IN AGREEMENT NOW WITH MORE PROGRESSIVE SYSTEM...WITH THE TROUGH
AXIS EAST OF SOUTHEAST MICHIGAN BY 00Z SATURDAY. STILL...GFS REMAINS
A HOLDOUT FOR A STRONGER...SOMEWHAT PHASED SYSTEM. PREFERENCE IS
WITH MAJORITY OF THE SOLUTIONS (NON-GFS)...AND WILL JUST CARRY
MODERATE CHANCE POPS DURING FRIDAY. WITH THE NORTHERN STREAM
TROUGH...THERE WILL BE SUFFICIENT COLD AIR COMING IN TO SUPPORT
SNOW...BUT PRECIPITATION WILL LIKELY HAVE SHUT OFF BY THE TIME THIS
OCCURS. STILL...850 MB TEMPS WILL SNEAK DOWN INTO THE LOW NEGATIVE
SINGLE NUMBERS SATURDAY MORNING...PRODUCING A CHILLY START TO THE
WEEKEND. HEIGHTS REBOUND QUICKLY WITH UPPER LEVEL RIDGE AXIS SLIDING
THROUGH OVER THE WEEKEND...WHICH SHOULD ALLOW FOR MAX TEMPS TO MAKE
A RUN TOWARD 60 DEGREES ON SUNDAY AHEAD OF THE NEXT COLD FRONT...AS
00Z EURO INDICATING 850 MB TEMPS RISING UP TO 8 C...WHICH WOULD
SUPPORT MUCH WARMER READINGS...BUT CLOUDS AND CHANCE OF RAIN SHOWERS
LEADS TO MORE CONSERVATIVE APPROACH AT THIS TIME.

&&

.MARINE...

HIGH PRESSURE OVER THE CENTRAL GREAT LAKES THIS MORNING WILL PROVIDE
LIGHT WINDS TODAY. SOUTHEAST WINDS WILL BE ON THE INCREASE THIS
EVENING...AS THE HIGH SLIDES EAST...BUT WINDS ARE EXPECTED TO REMAIN
BELOW 30 KNOTS TONIGHT. LONG FETCH WILL LEAD TO WAVES IN EXCESS OF 4
FEET OVER NORTHERN LAKE HURON...BUT NO SUCH CONCERNS OVER THE
NEARSHORE WATERS OF LAKE HURON. LIGHTER WINDS WILL RETURN THURSDAY
NIGHT INTO FRIDAY AS DIFFUSE COLD FRONT SLOWLY MOVES THROUGH THE
AREA...BRINGING WITH IT A CHANCE OF RAIN.

&&

.AVIATION...ISSUED 1253 AM EDT WED APR 16 2014

//DISCUSSION...

SURFACE RIDGING AND BUILDING HEIGHTS ALOFT WILL BRING QUIET WEATHER
THROUGHOUT THE PERIOD. THE BOTTOM OF THE STABLE LAYER IS FORECASTED
TO LOWER DOWN TO 3500-4000 FT AGL DURING THE DAY WHICH IS EXPECTED
TO LIMIT MUCH IN THE WAY OF LOW LEVEL CLOUDS.

//DTW THRESHOLD THREATS...

* NONE

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

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


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










000
FXUS63 KDTX 160453
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1253 AM EDT WED APR 16 2014

.AVIATION...

//DISCUSSION...

SURFACE RIDGING AND BUILDING HEIGHTS ALOFT WILL BRING QUIET WEATHER
THROUGHOUT THE PERIOD. THE BOTTOM OF THE STABLE LAYER IS FORECASTED
TO LOWER DOWN TO 3500-4000 FT AGL DURING THE DAY WHICH IS EXPECTED
TO LIMIT MUCH IN THE WAY OF LOW LEVEL CLOUDS.

//DTW THRESHOLD THREATS...

* NONE

&&

.PREV DISCUSSION...ISSUED 324 PM EDT TUE APR 15 2014

SHORT TERM... TODAY AND TONIGHT

BOUNDARY LAYER GROWTH AND MOISTURE FLUX OFF THE LAKES HAS
CONTRIBUTED TO WIDESPREAD CLOUD COVER AND SNOW SHOWERS/FLURRIES
THROUGHOUT THE AFTERNOON. THE HEIGHT FIELD HAS BEGUN TO REBOUND ACROSS
THE REGION IN RESPONSE TO AN APPROACHING SHORTWAVE THAT WILL LIFT
TOWARD IA/MN WEDNESDAY MORNING. THE RESULTANT PATTERN OF WARM
ADVECTION WILL ALLOW TEMPERATURES ALOFT TO WARM A BIT OVERNIGHT, BUT
THE SURFACE GRADIENT WILL BE WEAK AND EARLY DECOUPLING IS FAVORED AS
SKIES CLEAR UNDER THE INFLUENCE OF BUILDING HIGH PRESSURE AND
NOCTURNAL STABILIZATION. CONTINUED MENTION OF FLURRIES THROUGH 8PM
WITH POORLY ORGANIZED CELLULAR TYPE CONVECTION, BUT REMOVED POPS AS
MEASURABLE POTENTIAL APPEARS TO BE NIL FROM HERE ON OUT WITH LOSS
OF BANDING AND DECREASING INSTABILITY. LOWS WILL PLUMMET UNDER WHAT
REMAINS OF SNOW COVER, CALM WINDS, AND MOSTLY CLEAR SKIES. RECORD OR
NEAR-RECORD LOWS IN THE TEENS TO AROUND 20 ARE LIKELY (SEE CLIMATE
SECTION).

LONG TERM...WEDNESDAY THROUGH NEXT TUESDAY

AN UPPER LEVEL WAVE...CURRENTLY VISIBLE OVER THE PACIFIC NORTHWEST
ON WATER VAPOR IMAGERY...WILL EMERGE OVER THE NORTHERN PLAINS ON
WEDNESDAY AND OVER THE WESTERN GREAT LAKES WEDNESDAY NIGHT. THIS
WAVE WILL BRING A BAROCLINIC ZONE THROUGH THE GREAT LAKES REGION ON
THURSDAY...HALTING OVER THE CENTRAL GREAT LAKES AS THE MAIN WAVE
TAKES A TURN NORTHEAST TOWARDS JAMES BAY. THIS BAROCLINIC ZONE WILL
WEAKEN AS THE MAIN ENERGY EJECTS NORTHEAST AND HALT ITS EASTWARD
PROGRESS...KEEPING SOUTHEAST MICHIGAN ON THE DRY SIDE OF THIS
BOUNDARY. TEMPERATURES ARE EXPECTED TO RISE TO AROUND 60 AHEAD OF
THIS BOUNDARY ON THURSDAY WITH MODERATE WARM AIR ADVECTION AS LOW
LEVEL WINDS TURN SOUTHERLY.

A BETTER DEFINED TROUGH TRACKING ACROSS THE NORTHERN CONUS WILL PUSH
THE AFOREMENTIONED BOUNDARY THROUGH THE CENTRAL GREAT LAKES THURSDAY
NIGHT AND FRIDAY ON ITS WAY TO THE EAST COAST. THERE ARE STILL
SUBSTANTIAL TIMING ISSUES AMONGST THE NWP MODELS REGARDING THE
TIMING OF THIS BOUNDARY...WHICH HAS IMPLICATIONS ON FRIDAYS HIGH
TEMPERATURES AS A SOONER FROPA WOULD MEAN LOWER HIGH TEMPERATURES
AND A SOONER CHANGEOVER TO WET SNOW AS COLDER AIR FILTERS IN FROM
THE NORTH. STILL FAVOR THE PHASED SOLUTION PRESENTED BY THE GFS
WHICH WOULD SUPPORT RAIN FRIDAY CHANGING OVER TO WET SNOW FRIDAY
NIGHT WITH A SLOWER FROPA.

THE MAIN FEATURE FOR THIS WEEKEND WILL BE THE BATTLE BETWEEN A
SPRAWLING AREA OF HIGH SURFACE PRESSURE VS A STRUNG OUT FRONTAL
BOUNDARY ACROSS THE REGION. NWP GUIDANCE HAS DIFFERING VIEWS OF THE
STRENGTH OF THE SURFACE PRESSURE /ECMWF 4 HPA HIGHER THAN GFS/.
EVEN IF THE SURFACE LOW AND ASSOCIATED FRONT GAIN MORE UPPER LEVEL
SUPPORT...THE ONSET OF RAIN SHOULD HOLD OFF UNTIL THE AFTERNOON
HOURS OF EASTER. TIMING OF RAIN/EXIT OF THE COLD FRONT ON MONDAY IS
OUT OF PHASE IN THE MODELS...SO A CHANCE POP REMAINS IN THE FORECAST
FOR SEVERAL PERIODS DESPITE THE LIKELY SHORT PRECIP WINDOW.

MARINE...

NORTHWEST WINDS OF 20 TO 30 KNOTS LATE THIS AFTERNOON WILL DIMINISH
RAPIDLY THIS EVENING. SIGNIFICANT WAVE HEIGHTS WILL BUILD TO 7 FEET
OR HIGHER OVER THE OPEN WATERS OF CENTRAL LAKE HURON AND WILL BE IN
EXCESS OF 4 FEET ALONG THE EXPOSED NEARSHORE WATERS OF THE THUMB.
THIS IN COMBINATION WITH FREQUENT GUSTS OF 25 KNOTS SUPPORTS
CONTINUANCE OF THE SMALL CRAFT ADVISORIES FOR LAKE HURON THROUGH THE
EVENING HOURS. WINDS AND WAVES WILL QUICKLY SUBSIDE WITH THE ARRIVAL
OF HIGH PRESSURE TONIGHT. THIS HIGH WILL SLOWLY SLIDE EAST ON
WEDNESDAY...LEADING TO INCREASING SOUTHEAST WINDS INTO WEDNESDAY
NIGHT...BUT STILL REMAINING BELOW 30 KNOTS WITH WAVES BELOW HEADLINE
CRITERIA.

CLIMATE...

RECORD LOW HIGH TEMPERATURE FOR APRIL 15:

DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

RECORD LOWS FOR APRIL 16:

DTW 17 (1875)
FNT 21 (1935)
MBS 21 (1935)

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

AVIATION.....CB
SHORT TERM...JVC
LONG TERM....KURIMSKI/MM
MARINE.......KURIMSKI
CLIMATE......JVC


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











000
FXUS63 KDTX 152347
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
747 PM EDT TUE APR 15 2014


.AVIATION...

//DISCUSSION...

DIURNAL INSTABILITY SNOW SHOWERS WILL DISSIPATE WITHIN THE HOUR.
SURFACE RIDGING AND BUILDING HEIGHTS ALOFT WILL BRING QUIET WEATHER
THROUGH THE PERIOD. THE BOTTOM OF THE STABLE LAYER IS FORECASTED TO
LOWER DOWN 3500-4000 FT AGL TOMORROW WHICH IS EXPECTED TO LIMIT MUCH
IN THE WAY OF BOUNDARY LAYER CLOUD.

//DTW THRESHOLD THREATS...

* NONE

&&

.PREV DISCUSSION...ISSUED 324 PM EDT TUE APR 15 2014

SHORT TERM... TODAY AND TONIGHT

BOUNDARY LAYER GROWTH AND MOISTURE FLUX OFF THE LAKES HAS
CONTRIBUTED TO WIDESPREAD CLOUD COVER AND SNOW SHOWERS/FLURRIES
THROUGHOUT THE AFTERNOON. THE HEIGHT FIELD HAS BEGUN TO REBOUND ACROSS
THE REGION IN RESPONSE TO AN APPROACHING SHORTWAVE THAT WILL LIFT
TOWARD IA/MN WEDNESDAY MORNING. THE RESULTANT PATTERN OF WARM
ADVECTION WILL ALLOW TEMPERATURES ALOFT TO WARM A BIT OVERNIGHT, BUT
THE SURFACE GRADIENT WILL BE WEAK AND EARLY DECOUPLING IS FAVORED AS
SKIES CLEAR UNDER THE INFLUENCE OF BUILDING HIGH PRESSURE AND
NOCTURNAL STABILIZATION. CONTINUED MENTION OF FLURRIES THROUGH 8PM
WITH POORLY ORGANIZED CELLULAR TYPE CONVECTION, BUT REMOVED POPS AS
MEASURABLE POTENTIAL APPEARS TO BE NIL FROM HERE ON OUT WITH LOSS
OF BANDING AND DECREASING INSTABILITY. LOWS WILL PLUMMET UNDER WHAT
REMAINS OF SNOW COVER, CALM WINDS, AND MOSTLY CLEAR SKIES. RECORD OR
NEAR-RECORD LOWS IN THE TEENS TO AROUND 20 ARE LIKELY (SEE CLIMATE
SECTION).

LONG TERM...WEDNESDAY THROUGH NEXT TUESDAY

AN UPPER LEVEL WAVE...CURRENTLY VISIBLE OVER THE PACIFIC NORTHWEST
ON WATER VAPOR IMAGERY...WILL EMERGE OVER THE NORTHERN PLAINS ON
WEDNESDAY AND OVER THE WESTERN GREAT LAKES WEDNESDAY NIGHT. THIS
WAVE WILL BRING A BAROCLINIC ZONE THROUGH THE GREAT LAKES REGION ON
THURSDAY...HALTING OVER THE CENTRAL GREAT LAKES AS THE MAIN WAVE
TAKES A TURN NORTHEAST TOWARDS JAMES BAY. THIS BAROCLINIC ZONE WILL
WEAKEN AS THE MAIN ENERGY EJECTS NORTHEAST AND HALT ITS EASTWARD
PROGRESS...KEEPING SOUTHEAST MICHIGAN ON THE DRY SIDE OF THIS
BOUNDARY. TEMPERATURES ARE EXPECTED TO RISE TO AROUND 60 AHEAD OF
THIS BOUNDARY ON THURSDAY WITH MODERATE WARM AIR ADVECTION AS LOW
LEVEL WINDS TURN SOUTHERLY.

A BETTER DEFINED TROUGH TRACKING ACROSS THE NORTHERN CONUS WILL PUSH
THE AFOREMENTIONED BOUNDARY THROUGH THE CENTRAL GREAT LAKES THURSDAY
NIGHT AND FRIDAY ON ITS WAY TO THE EAST COAST. THERE ARE STILL
SUBSTANTIAL TIMING ISSUES AMONGST THE NWP MODELS REGARGING THE
TIMING OF THIS BOUNDARY...WHICH HAS IMPLICATIONS ON FRIDAYS HIGH
TEMPERATURES AS A SOONER FROPA WOULD MEAN LOWER HIGH TEMPERATURES
AND A SOONER CHANGEOVER TO WET SNOW AS COLDER AIR FILTERS IN FROM
THE NORTH. STILL FAVOR THE PHASED SOLUTION PRESENTED BY THE GFS
WHICH WOULD SUPPORT RAIN FRIDAY CHANGING OVER TO WET SNOW FRIDAY
NIGHT WITH A SLOWER FROPA.

THE MAIN FEATURE FOR THIS WEEKEND WILL BE THE BATTLE BETWEEN A
SPRAWLING AREA OF HIGH SURFACE PRESSURE VS A STRUNG OUT FRONTAL
BOUNDARY ACROSS THE REGION. NWP GUIDANCE HAS DIFFERING VIEWS OF THE
STRENGTH OF THE SURFACE PRESSURE /ECMWF 4 HPA HIGHER THAN GFS/.
EVEN IF THE SURFACE LOW AND ASSOCIATED FRONT GAIN MORE UPPER LEVEL
SUPPORT...THE ONSET OF RAIN SHOULD HOLD OFF UNTIL THE AFTERNOON
HOURS OF EASTER. TIMING OF RAIN/EXIT OF THE COLD FRONT ON MONDAY IS
OUT OF PHASE IN THE MODELS...SO A CHANCE POP REMAINS IN THE FORECAST
FOR SEVERAL PERIODS DESPITE THE LIKELY SHORT PRECIP WINDOW.

MARINE...

NORTHWEST WINDS OF 20 TO 30 KNOTS LATE THIS AFTERNOON WILL DIMINISH
RAPIDLY THIS EVENING. SIGNIFICANT WAVE HEIGHTS WILL BUILD TO 7 FEET
OR HIGHER OVER THE OPEN WATERS OF CENTRAL LAKE HURON AND WILL BE IN
EXCESS OF 4 FEET ALONG THE EXPOSED NEARSHORE WATERS OF THE THUMB.
THIS IN COMBINATION WITH FREQUENT GUSTS OF 25 KNOTS SUPPORTS
CONTINUANCE OF THE SMALL CRAFT ADVISORIES FOR LAKE HURON THROUGH THE
EVENING HOURS. WINDS AND WAVES WILL QUICKLY SUBSIDE WITH THE ARRIVAL
OF HIGH PRESSURE TONIGHT. THIS HIGH WILL SLOWLY SLIDE EAST ON
WEDNESDAY...LEADING TO INCREASING SOUTHEAST WINDS INTO WEDNESDAY
NIGHT...BUT STILL REMAINING BELOW 30 KNOTS WITH WAVES BELOW HEADLINE
CRITERIA.

CLIMATE...

RECORD LOW HIGH TEMPERATURE FOR APRIL 15:

DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

RECORD LOWS FOR APRIL 16:

DTW 17 (1875)
FNT 21 (1935)
MBS 21 (1935)

&&

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

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL MIDNIGHT WEDNESDAY.

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

&&

$$

AVIATION.....CB
SHORT TERM...JVC
LONG TERM....KURIMSKI/MM
MARINE.......KURIMSKI
CLIMATE......JVC
CLIMATE......CB


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








000
FXUS63 KDTX 151924
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
324 PM EDT TUE APR 15 2014

.SHORT TERM... TODAY AND TONIGHT

BOUNDARY LAYER GROWTH AND MOISTURE FLUX OFF THE LAKES HAS
CONTRIBUTED TO WIDESPREAD CLOUD COVER AND SNOW SHOWERS/FLURRIES
THROUGHOUT THE AFTERNOON. THE HEIGHT FIELD HAS BEGUN TO REBOUND ACROSS
THE REGION IN RESPONSE TO AN APPROACHING SHORTWAVE THAT WILL LIFT
TOWARD IA/MN WEDNESDAY MORNING. THE RESULTANT PATTERN OF WARM
ADVECTION WILL ALLOW TEMPERATURES ALOFT TO WARM A BIT OVERNIGHT, BUT
THE SURFACE GRADIENT WILL BE WEAK AND EARLY DECOUPLING IS FAVORED AS
SKIES CLEAR UNDER THE INFLUENCE OF BUILDING HIGH PRESSURE AND
NOCTURNAL STABILIZATION. CONTINUED MENTION OF FLURRIES THROUGH 8PM
WITH POORLY ORGANIZED CELLULAR TYPE CONVECTION, BUT REMOVED POPS AS
MEASURABLE POTENTIAL APPEARS TO BE NIL FROM HERE ON OUT WITH LOSS
OF BANDING AND DECREASING INSTABILITY. LOWS WILL PLUMMET UNDER WHAT
REMAINS OF SNOW COVER, CALM WINDS, AND MOSTLY CLEAR SKIES. RECORD OR
NEAR-RECORD LOWS IN THE TEENS TO AROUND 20 ARE LIKELY (SEE CLIMATE
SECTION).

&&

.LONG TERM...WEDNESDAY THROUGH NEXT TUESDAY

AN UPPER LEVEL WAVE...CURRENTLY VISIBLE OVER THE PACIFIC NORTHWEST
ON WATER VAPOR IMAGERY...WILL EMERGE OVER THE NORTHERN PLAINS ON
WEDNESDAY AND OVER THE WESTERN GREAT LAKES WEDNESDAY NIGHT. THIS
WAVE WILL BRING A BAROCLINIC ZONE THROUGH THE GREAT LAKES REGION ON
THURSDAY...HALTING OVER THE CENTRAL GREAT LAKES AS THE MAIN WAVE
TAKES A TURN NORTHEAST TOWARDS JAMES BAY. THIS BAROCLINIC ZONE WILL
WEAKEN AS THE MAIN ENERGY EJECTS NORTHEAST AND HALT ITS EASTWARD
PROGRESS...KEEPING SOUTHEAST MICHIGAN ON THE DRY SIDE OF THIS
BOUNDARY. TEMPERATURES ARE EXPECTED TO RISE TO AROUND 60 AHEAD OF
THIS BOUNDARY ON THURSDAY WITH MODERATE WARM AIR ADVECTION AS LOW
LEVEL WINDS TURN SOUTHERLY.

A BETTER DEFINED TROUGH TRACKING ACROSS THE NORTHERN CONUS WILL PUSH
THE AFOREMENTIONED BOUNDARY THROUGH THE CENTRAL GREAT LAKES THURSDAY
NIGHT AND FRIDAY ON ITS WAY TO THE EAST COAST. THERE ARE STILL
SUBSTANTIAL TIMING ISSUES AMONGST THE NWP MODELS REGARGING THE
TIMING OF THIS BOUNDARY...WHICH HAS IMPLICATIONS ON FRIDAYS HIGH
TEMPERATURES AS A SOONER FROPA WOULD MEAN LOWER HIGH TEMPERATURES
AND A SOONER CHANGEOVER TO WET SNOW AS COLDER AIR FILTERS IN FROM
THE NORTH. STILL FAVOR THE PHASED SOLUTION PRESENTED BY THE GFS
WHICH WOULD SUPPORT RAIN FRIDAY CHANGING OVER TO WET SNOW FRIDAY
NIGHT WITH A SLOWER FROPA.

THE MAIN FEATURE FOR THIS WEEKEND WILL BE THE BATTLE BETWEEN A
SPRAWLING AREA OF HIGH SURFACE PRESSURE VS A STRUNG OUT FRONTAL
BOUNDARY ACROSS THE REGION. NWP GUIDANCE HAS DIFFERING VIEWS OF THE
STRENGTH OF THE SURFACE PRESSURE /ECMWF 4 HPA HIGHER THAN GFS/.
EVEN IF THE SURFACE LOW AND ASSOCIATED FRONT GAIN MORE UPPER LEVEL
SUPPORT...THE ONSET OF RAIN SHOULD HOLD OFF UNTIL THE AFTERNOON
HOURS OF EASTER. TIMING OF RAIN/EXIT OF THE COLD FRONT ON MONDAY IS
OUT OF PHASE IN THE MODELS...SO A CHANCE POP REMAINS IN THE FORECAST
FOR SEVERAL PERIODS DESPITE THE LIKELY SHORT PRECIP WINDOW.

&&

.MARINE...

NORTHWEST WINDS OF 20 TO 30 KNOTS LATE THIS AFTERNOON WILL DIMINISH
RAPIDLY THIS EVENING. SIGNIFICANT WAVE HEIGHTS WILL BUILD TO 7 FEET
OR HIGHER OVER THE OPEN WATERS OF CENTRAL LAKE HURON AND WILL BE IN
EXCESS OF 4 FEET ALONG THE EXPOSED NEARSHORE WATERS OF THE THUMB.
THIS IN COMBINATION WITH FREQUENT GUSTS OF 25 KNOTS SUPPORTS
CONTINUANCE OF THE SMALL CRAFT ADVISORIES FOR LAKE HURON THROUGH THE
EVENING HOURS. WINDS AND WAVES WILL QUICKLY SUBSIDE WITH THE ARRIVAL
OF HIGH PRESSURE TONIGHT. THIS HIGH WILL SLOWLY SLIDE EAST ON
WEDNESDAY...LEADING TO INCREASING SOUTHEAST WINDS INTO WEDNESDAY
NIGHT...BUT STILL REMAINING BELOW 30 KNOTS WITH WAVES BELOW HEADLINE
CRITERIA.

&&

.CLIMATE...

RECORD LOW HIGH TEMPERATURE FOR APRIL 15:

DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

RECORD LOWS FOR APRIL 16:

DTW 17 (1875)
FNT 21 (1935)
MBS 21 (1935)

&&

.AVIATION...ISSUED 105 PM EDT TUE APR 15 2014

//DISCUSSION...

COLD ADVECTION AND DIURNAL HEATING WILL FACILITATE WIDESPREAD
FLURRIES AND OCCASIONAL SNOW SHOWERS FOR THE REMAINDER OF THE
DAYLIGHT HOURS ALONG WITH LOW VFR CEILING. VISIBILITY MAY BRIEFLY
DROP BELOW 3SM IN HEAVIER SHOWERS BUT WILL OTHERWISE REMAIN VFR.
GUSTY NORTHWEST WINDS WILL SUBSIDE AFTER SUNSET AS DIURNAL
STABILIZATION TAKES PLACE WHILE BUILDING HIGH PRESSURE ALLOWS FOR
CLEARING OF LOW CLOUDS. CONDITIONS WILL THEN REMAIN CLEAR BELOW
10KFT FOR THE REMAINDER OF THE NIGHT AS LIGHT SURFACE WINDS
GRADUALLY BACK TO THE SOUTHWEST.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET TODAY.

* HIGH CONFIDENCE IN PTYPE OF SNOW

&&

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

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL MIDNIGHT WEDNESDAY.

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

&&

$$

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


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








000
FXUS63 KDTX 151705
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
105 PM EDT TUE APR 15 2014


.AVIATION...

//DISCUSSION...

COLD ADVECTION AND DIURNAL HEATING WILL FACILITATE WIDESPREAD
FLURRIES AND OCCASIONAL SNOW SHOWERS FOR THE REMAINDER OF THE
DAYLIGHT HOURS ALONG WITH LOW VFR CEILING. VISIBILITY MAY BRIEFLY
DROP BELOW 3SM IN HEAVIER SHOWERS BUT WILL OTHERWISE REMAIN VFR.
GUSTY NORTHWEST WINDS WILL SUBSIDE AFTER SUNSET AS DIURNAL
STABILIZATION TAKES PLACE WHILE BUILDING HIGH PRESSURE ALLOWS FOR
CLEARING OF LOW CLOUDS. CONDITIONS WILL THEN REMAIN CLEAR BELOW
10KFT FOR THE REMAINDER OF THE NIGHT AS LIGHT SURFACE WINDS
GRADUALLY BACK TO THE SOUTHWEST.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET TODAY.

* HIGH CONFIDENCE IN PTYPE OF SNOW

&&

.PREV DISCUSSION...ISSUED 352 AM EDT TUE APR 15 2014

SHORT TERM... TODAY AND TONIGHT

THE TRANSITION FROM RAIN TO SNOW WAS COMPLETE BY MIDNIGHT OVER ALL
OF SE MICHIGAN. THE QUESTION NOW BECOMES HOW MUCH ACCUMULATION WILL
OCCUR WITH THE REMAINING MOISTURE IN THE SYSTEM WITHIN STRONG AND
WELL ORGANIZED MESOSCALE FORCING. SATELLITE IMAGERY AND MODEL
ANALYSIS FIELDS INDICATE A CLASSIC SET UP OF FRONTOGENETICAL FORCING
IN PROGRESS OVER SE MICHIGAN SUPPORTED BY A SW-NE ORIENTED 150 KNOT
UPPER JET MAX. THE RESULTING AGEOSTROPHIC CIRCULATION INITIALLY
ACTIVATED THE MID TO UPPER LEVELS OF THE FRONTAL ZONE WITH A BAND OF
SNOW OVER WESTERN AND NORTHERN LOWER MICHIGAN THAT PRODUCED 1 TO 3
INCHES OF ACCUMULATION. RADAR TRENDS SINCE MIDNIGHT HAVE SHOWN THIS
SHIFTED EASTWARD AS A RESULTANT COMBINATION OF LARGE SCALE
PROGRESSION OF THE FRONTAL ZONE AND A TENDENCY FOR LIFT TO MIGRATE
TOWARD LOWER ALTITUDES WHERE SPECIFIC HUMIDITY IS IN THE 3-4 G/KG
RANGE. MODEL CROSS SECTIONS INDICATE THE LIFT OCCURRING IN AN
UNSTABLE PROFILE BETWEEN 700 AND 400 MB WHERE THETA-E IS FOLDED
THROUGH MULTIPLE LEVELS ALLOWING THE FRONTAL CIRCULATION TO MODULATE
A MATURE BAND OF SNOW DURING THE EARLY MORNING HOURS. LOCAL OFFICE
OBSERVATIONS ILLUSTRATE THE EFFECTIVENESS OF THE BAND WITH 1 INCH
PER HOUR RATES OF BIG AGGREGATES BETWEEN MIDNIGHT AND 2 AM LIKELY
REPRESENTATIVE ALONG THE HIGHER TERRAIN UP INTO SANILAC COUNTY AND
SETTING UP SOLID 3 INCH TOTALS WITH A FEW 4 INCH REPORTS POSSIBLE.
LOCATIONS TO THE NORTH TOWARD THE TRI CITIES WILL BE LIMITED BY
DURATION TO ABOUT AN INCH OF ACCUMULATION. FLINT AND THE NORTHERN
THUMB WILL BE CLOSER TO THE MATURE PART OF THE BAND FOR THE REST OF
THE EVENT FOR 1 TO 2 INCH TOTALS. THE DTW AREA TO THE OHIO BORDER
STARTED OUT WITH LOWER RATIOS AT FIRST, DUE TO WARMER SURFACE
TEMPERATURE, BUT WILL NOT BE TOO FAR BEHIND THE HIGHER TERRAIN AREAS
IN ACCUMULATION AS THE PRIMARY BANDS AFFECT THAT AREA THROUGH
SUNRISE. SOLID 2 TO 3 INCH TOTALS ARE EXPECTED THERE BEFORE THE
PATTERN EXITS EASTWARD BY 8 AM OR SO.

THE REST OF THE DAY WILL BE DOMINATED BY STRONG COLD ADVECTION THAT
WILL BE ABLE TO RESIST MID APRIL SURFACE HEATING ENOUGH TO LIMIT MAX
TEMPS THE UPPER 30S. MODEL 850 MB TEMPERATURES SETTLING INTO THE -13
TO -16C RANGE BY LATE AFTERNOON IS A STRONG ENDORSEMENT ON THE COLD
NATURE OF THE AIR MASS. BOUNDARY LAYER MOISTURE AND INSTABILITY WILL
KEEP PLENTY OF CLOUDS STIRRED UP WHICH WILL FURTHER LIMIT
TEMPERATURES. THERE MAY BE A FEW FLURRIES AS WELL, ALTHOUGH MODEL
SOUNDINGS SHOW THE AIR TO BE ON THE DRY SIDE BELOW CLOUD BASE. THE
MAIN TAKEAWAY IS THAT THE COLD AFTERNOON TEMPERATURES WILL HAVE
READINGS WELL POSITIONED TO MAKE A RUN AT RECORD LOWS TONIGHT. A
SHORT PERIOD OF IDEAL RADIATIONAL COOLING IS EXPECTED TO OCCUR
AROUND MIDNIGHT AFTER VERY LITTLE MELTING OF THE NEW SNOW COVER
DURING THE DAY COMBINED WITH THE DISSIPATION OF LOWER CLOUDS AND
DIMINISHING WIND. EXPECT MIN TEMPS IN THE TEENS TO LOWER 20S BEFORE
HIGH CLOUDS THICKEN AND THE WIND BACKS TO SOUTHWEST TOWARD SUNRISE
WEDNESDAY. SEE CLIMATE SECTION BELOW FOR STATS.

LONG TERM...

NOT MUCH OF A WARMUP EXPECTED DURING THE EXTENDED PERIOD...WITH EVEN
A LOW CHANCE FOR ADDITIONAL SNOW FRIDAY NIGHT (SEE 00Z GFS).

UPPER LEVEL WAVE/TROUGH CURRENTLY MOVING ONSHORE OF SOUTHERN BRITISH
COLUMBIA/WASHINGTON WILL SWING THROUGH THE NORTHERN PLAINS WEDNESDAY
AND INTO THE WESTERN GREAT LAKES THURSDAY MORNING. TIGHT BAROCLINIC
ZONE WILL RESIDE OVER THE GREAT LAKES REGION...BUT MID LEVEL
FORCING/FGEN LOOKS TO BE RESIDING NORTH OF SOUTHEAST MICHIGAN. A
DRAMATIC WEAKENING TREND LOOKS TO BE TAKING PLACE DURING THURSDAY AS
SYSTEM ENCOUNTERS REMNANT UPPER LEVEL CONFLUENT FLOW FROM DEPARTING
VORTEX OVER HUDSON BAY.

POTENT PV ANOMALY RETROGRADING THROUGH CENTRAL CANADA DURING THE MID
WEEK PERIOD WILL BE KEY PLAYER AS WE END THE WORK WEEK...WITH
CANADIAN/GFS/EURO ALL SHOWING SUBSTANTIAL TIMING ISSUES...ALONG WITH
THE ISSUES DEALING WITH THE INTERACTION OF THE SOUTHERN ENERGY
COMING OUT OF THE FOUR CORNERS REGION. GFS INDICATING THE OPTIMAL
INTERACTION/PHASING...AND THUS WOULD SUPPORT RAIN CHANGING OVER TO
WET SNOW FRIDAY NIGHT. 00Z EURO/CANADIAN BOTH KEEPING A BIT MORE
WAVE SEPARATION...AND THUS MORE PROGRESSIVE AND NON-PHASED
SOLUTIONS.

MARINE...

NORTHWEST WINDS OF 20 TO 30 KNOTS TODAY WILL BE COMMON AS COLD
AIRMASS WILL BE IN PLACE. GUSTS COULD EVEN BRIEFLY REACH GALES OVER
THE OPEN WATERS OF LAKE HURON DURING THE AFTERNOON. SIGNIFICANT WAVE
HEIGHTS WILL BUILD TO 7 FEET OR HIGHER OVER THE OPEN WATERS OF
CENTRAL LAKE HURON AND WILL BE IN EXCESS OF 4 FEET ALONG THE EXPOSED
NEARSHORE WATERS OF THE THUMB. THIS IN COMBINATION WITH FREQUENT
GUSTS OF 25 KNOTS SUPPORTS CONTINUANCE OF THE SMALL CRAFT ADVISORIES
FOR LAKE HURON. WINDS AND WAVES WILL QUICKLY SUBSIDE WITH THE
ARRIVAL OF HIGH PRESSURE TONIGHT. THIS HIGH WILL SLOWLY SLIDE EAST
ON WEDNESDAY...LEADING TO INCREASING SOUTHEAST WINDS INTO WEDNESDAY
NIGHT...BUT STILL REMAINING BELOW 30 KNOTS.

CLIMATE...

SNOWIEST WINTER SEASON (NOT INCLUDING NEW SNOW TODAY)

CITY       2013-2014        RECORD        TO TIE RECORD

FLINT       82.6"      82.9" (1974-75)         0.3"
DETROIT     91.7"      93.6" (1880-81)         1.9"

RECORD LOW MAX TEMPERATURE FOR APRIL 15:

DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

RECORD MINS FOR APRIL 16:

DTW 17 (1875)
FNT 21 (1935)
MBS 21 (1935)

&&

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

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL MIDNIGHT WEDNESDAY.

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

&&

$$

AVIATION.....JVC
SHORT TERM...BT
LONG TERM....SF
MARINE.......SF
CLIMATE......BT/SF
CLIMATE......JVC


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








000
FXUS63 KDTX 151132
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
732 AM EDT TUE APR 15 2014

.AVIATION...

//DISCUSSION...

EARLY MORNING SNOWFALL EXITING TO THE EAST WILL LEAVE MVFR CEILING
AND COLD AIR IN ITS WAKE FOR THE MORNING. CLOUD CONDITIONS WILL
IMPROVE TO VFR BY AFTERNOON BUT WITH A FEW FLURRIES AS SURFACE
HEATING BATTLES THE COLD AIR. OTHERWISE...NORTHWEST WIND GUSTS NEAR
20 KNOTS ARE ALL THAT WILL HAMPER AVIATION OPERATIONS. THE GUSTS
WILL DIMINISH DURING THE EVENING WITH HIGH PRESSURE SUPPORTING VFR
CONDITIONS THROUGH SUNRISE WEDNESDAY.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET TODAY.

&&

.PREV DISCUSSION...ISSUED 352 AM EDT TUE APR 15 2014

SHORT TERM... TODAY AND TONIGHT

THE TRANSITION FROM RAIN TO SNOW WAS COMPLETE BY MIDNIGHT OVER ALL
OF SE MICHIGAN. THE QUESTION NOW BECOMES HOW MUCH ACCUMULATION WILL
OCCUR WITH THE REMAINING MOISTURE IN THE SYSTEM WITHIN STRONG AND
WELL ORGANIZED MESOSCALE FORCING. SATELLITE IMAGERY AND MODEL
ANALYSIS FIELDS INDICATE A CLASSIC SET UP OF FRONTOGENETICAL FORCING
IN PROGRESS OVER SE MICHIGAN SUPPORTED BY A SW-NE ORIENTED 150 KNOT
UPPER JET MAX. THE RESULTING AGEOSTROPHIC CIRCULATION INITIALLY
ACTIVATED THE MID TO UPPER LEVELS OF THE FRONTAL ZONE WITH A BAND OF
SNOW OVER WESTERN AND NORTHERN LOWER MICHIGAN THAT PRODUCED 1 TO 3
INCHES OF ACCUMULATION. RADAR TRENDS SINCE MIDNIGHT HAVE SHOWN THIS
SHIFTED EASTWARD AS A RESULTANT COMBINATION OF LARGE SCALE
PROGRESSION OF THE FRONTAL ZONE AND A TENDENCY FOR LIFT TO MIGRATE
TOWARD LOWER ALTITUDES WHERE SPECIFIC HUMIDITY IS IN THE 3-4 G/KG
RANGE. MODEL CROSS SECTIONS INDICATE THE LIFT OCCURRING IN AN
UNSTABLE PROFILE BETWEEN 700 AND 400 MB WHERE THETA-E IS FOLDED
THROUGH MULTIPLE LEVELS ALLOWING THE FRONTAL CIRCULATION TO MODULATE
A MATURE BAND OF SNOW DURING THE EARLY MORNING HOURS. LOCAL OFFICE
OBSERVATIONS ILLUSTRATE THE EFFECTIVENESS OF THE BAND WITH 1 INCH
PER HOUR RATES OF BIG AGGREGATES BETWEEN MIDNIGHT AND 2 AM LIKELY
REPRESENTATIVE ALONG THE HIGHER TERRAIN UP INTO SANILAC COUNTY AND
SETTING UP SOLID 3 INCH TOTALS WITH A FEW 4 INCH REPORTS POSSIBLE.
LOCATIONS TO THE NORTH TOWARD THE TRI CITIES WILL BE LIMITED BY
DURATION TO ABOUT AN INCH OF ACCUMULATION. FLINT AND THE NORTHERN
THUMB WILL BE CLOSER TO THE MATURE PART OF THE BAND FOR THE REST OF
THE EVENT FOR 1 TO 2 INCH TOTALS. THE DTW AREA TO THE OHIO BORDER
STARTED OUT WITH LOWER RATIOS AT FIRST, DUE TO WARMER SURFACE
TEMPERATURE, BUT WILL NOT BE TOO FAR BEHIND THE HIGHER TERRAIN AREAS
IN ACCUMULATION AS THE PRIMARY BANDS AFFECT THAT AREA THROUGH
SUNRISE. SOLID 2 TO 3 INCH TOTALS ARE EXPECTED THERE BEFORE THE
PATTERN EXITS EASTWARD BY 8 AM OR SO.

THE REST OF THE DAY WILL BE DOMINATED BY STRONG COLD ADVECTION THAT
WILL BE ABLE TO RESIST MID APRIL SURFACE HEATING ENOUGH TO LIMIT MAX
TEMPS THE UPPER 30S. MODEL 850 MB TEMPERATURES SETTLING INTO THE -13
TO -16C RANGE BY LATE AFTERNOON IS A STRONG ENDORSEMENT ON THE COLD
NATURE OF THE AIR MASS. BOUNDARY LAYER MOISTURE AND INSTABILITY WILL
KEEP PLENTY OF CLOUDS STIRRED UP WHICH WILL FURTHER LIMIT
TEMPERATURES. THERE MAY BE A FEW FLURRIES AS WELL, ALTHOUGH MODEL
SOUNDINGS SHOW THE AIR TO BE ON THE DRY SIDE BELOW CLOUD BASE. THE
MAIN TAKEAWAY IS THAT THE COLD AFTERNOON TEMPERATURES WILL HAVE
READINGS WELL POSITIONED TO MAKE A RUN AT RECORD LOWS TONIGHT. A
SHORT PERIOD OF IDEAL RADIATIONAL COOLING IS EXPECTED TO OCCUR
AROUND MIDNIGHT AFTER VERY LITTLE MELTING OF THE NEW SNOW COVER
DURING THE DAY COMBINED WITH THE DISSIPATION OF LOWER CLOUDS AND
DIMINISHING WIND. EXPECT MIN TEMPS IN THE TEENS TO LOWER 20S BEFORE
HIGH CLOUDS THICKEN AND THE WIND BACKS TO SOUTHWEST TOWARD SUNRISE
WEDNESDAY. SEE CLIMATE SECTION BELOW FOR STATS.

LONG TERM...

NOT MUCH OF A WARMUP EXPECTED DURING THE EXTENDED PERIOD...WITH EVEN
A LOW CHANCE FOR ADDITIONAL SNOW FRIDAY NIGHT (SEE 00Z GFS).

UPPER LEVEL WAVE/TROUGH CURRENTLY MOVING ONSHORE OF SOUTHERN BRITISH
COLUMBIA/WASHINGTON WILL SWING THROUGH THE NORTHERN PLAINS WEDNESDAY
AND INTO THE WESTERN GREAT LAKES THURSDAY MORNING. TIGHT BAROCLINIC
ZONE WILL RESIDE OVER THE GREAT LAKES REGION...BUT MID LEVEL
FORCING/FGEN LOOKS TO BE RESIDING NORTH OF SOUTHEAST MICHIGAN. A
DRAMATIC WEAKENING TREND LOOKS TO BE TAKING PLACE DURING THURSDAY AS
SYSTEM ENCOUNTERS REMNANT UPPER LEVEL CONFLUENT FLOW FROM DEPARTING
VORTEX OVER HUDSON BAY.

POTENT PV ANOMALY RETROGRADING THROUGH CENTRAL CANADA DURING THE MID
WEEK PERIOD WILL BE KEY PLAYER AS WE END THE WORK WEEK...WITH
CANADIAN/GFS/EURO ALL SHOWING SUBSTANTIAL TIMING ISSUES...ALONG WITH
THE ISSUES DEALING WITH THE INTERACTION OF THE SOUTHERN ENERGY
COMING OUT OF THE FOUR CORNERS REGION. GFS INDICATING THE OPTIMAL
INTERACTION/PHASING...AND THUS WOULD SUPPORT RAIN CHANGING OVER TO
WET SNOW FRIDAY NIGHT. 00Z EURO/CANADIAN BOTH KEEPING A BIT MORE
WAVE SEPARATION...AND THUS MORE PROGRESSIVE AND NON-PHASED
SOLUTIONS.

MARINE...

NORTHWEST WINDS OF 20 TO 30 KNOTS TODAY WILL BE COMMON AS COLD
AIRMASS WILL BE IN PLACE. GUSTS COULD EVEN BRIEFLY REACH GALES OVER
THE OPEN WATERS OF LAKE HURON DURING THE AFTERNOON. SIGNIFICANT WAVE
HEIGHTS WILL BUILD TO 7 FEET OR HIGHER OVER THE OPEN WATERS OF
CENTRAL LAKE HURON AND WILL BE IN EXCESS OF 4 FEET ALONG THE EXPOSED
NEARSHORE WATERS OF THE THUMB. THIS IN COMBINATION WITH FREQUENT
GUSTS OF 25 KNOTS SUPPORTS CONTINUANCE OF THE SMALL CRAFT ADVISORIES
FOR LAKE HURON. WINDS AND WAVES WILL QUICKLY SUBSIDE WITH THE
ARRIVAL OF HIGH PRESSURE TONIGHT. THIS HIGH WILL SLOWLY SLIDE EAST
ON WEDNESDAY...LEADING TO INCREASING SOUTHEAST WINDS INTO WEDNESDAY
NIGHT...BUT STILL REMAINING BELOW 30 KNOTS.

CLIMATE...

SNOWIEST WINTER SEASON (NOT INCLUDING NEW SNOW TODAY)

CITY       2013-2014        RECORD        TO TIE RECORD

FLINT       82.6"      82.9" (1974-75)         0.3"
DETROIT     91.7"      93.6" (1880-81)         1.9"

RECORD LOW MAX TEMPERATURE FOR APRIL 15:

DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

RECORD MINS FOR APRIL 16:

DTW 17 (1875)
FNT 21 (1935)
MBS 21 (1935)

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL MIDNIGHT WEDNESDAY.

LAKE ST CLAIR...NONE.

MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....BT
SHORT TERM...BT
LONG TERM....SF
MARINE.......SF
CLIMATE......BT/SF


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








000
FXUS63 KDTX 150752
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
352 AM EDT TUE APR 15 2014

.SHORT TERM... TODAY AND TONIGHT

THE TRANSITION FROM RAIN TO SNOW WAS COMPLETE BY MIDNIGHT OVER ALL
OF SE MICHIGAN. THE QUESTION NOW BECOMES HOW MUCH ACCUMULATION WILL
OCCUR WITH THE REMAINING MOISTURE IN THE SYSTEM WITHIN STRONG AND
WELL ORGANIZED MESOSCALE FORCING. SATELLITE IMAGERY AND MODEL
ANALYSIS FIELDS INDICATE A CLASSIC SET UP OF FRONTOGENETICAL FORCING
IN PROGRESS OVER SE MICHIGAN SUPPORTED BY A SW-NE ORIENTED 150 KNOT
UPPER JET MAX. THE RESULTING AGEOSTROPHIC CIRCULATION INITIALLY
ACTIVATED THE MID TO UPPER LEVELS OF THE FRONTAL ZONE WITH A BAND OF
SNOW OVER WESTERN AND NORTHERN LOWER MICHIGAN THAT PRODUCED 1 TO 3
INCHES OF ACCUMULATION. RADAR TRENDS SINCE MIDNIGHT HAVE SHOWN THIS
SHIFTED EASTWARD AS A RESULTANT COMBINATION OF LARGE SCALE
PROGRESSION OF THE FRONTAL ZONE AND A TENDENCY FOR LIFT TO MIGRATE
TOWARD LOWER ALTITUDES WHERE SPECIFIC HUMIDITY IS IN THE 3-4 G/KG
RANGE. MODEL CROSS SECTIONS INDICATE THE LIFT OCCURRING IN AN
UNSTABLE PROFILE BETWEEN 700 AND 400 MB WHERE THETA-E IS FOLDED
THROUGH MULTIPLE LEVELS ALLOWING THE FRONTAL CIRCULATION TO MODULATE
A MATURE BAND OF SNOW DURING THE EARLY MORNING HOURS. LOCAL OFFICE
OBSERVATIONS ILLUSTRATE THE EFFECTIVENESS OF THE BAND WITH 1 INCH
PER HOUR RATES OF BIG AGGREGATES BETWEEN MIDNIGHT AND 2 AM LIKELY
REPRESENTATIVE ALONG THE HIGHER TERRAIN UP INTO SANILAC COUNTY AND
SETTING UP SOLID 3 INCH TOTALS WITH A FEW 4 INCH REPORTS POSSIBLE.
LOCATIONS TO THE NORTH TOWARD THE TRI CITIES WILL BE LIMITED BY
DURATION TO ABOUT AN INCH OF ACCUMULATION. FLINT AND THE NORTHERN
THUMB WILL BE CLOSER TO THE MATURE PART OF THE BAND FOR THE REST OF
THE EVENT FOR 1 TO 2 INCH TOTALS. THE DTW AREA TO THE OHIO BORDER
STARTED OUT WITH LOWER RATIOS AT FIRST, DUE TO WARMER SURFACE
TEMPERATURE, BUT WILL NOT BE TOO FAR BEHIND THE HIGHER TERRAIN AREAS
IN ACCUMULATION AS THE PRIMARY BANDS AFFECT THAT AREA THROUGH
SUNRISE. SOLID 2 TO 3 INCH TOTALS ARE EXPECTED THERE BEFORE THE
PATTERN EXITS EASTWARD BY 8 AM OR SO.

THE REST OF THE DAY WILL BE DOMINATED BY STRONG COLD ADVECTION THAT
WILL BE ABLE TO RESIST MID APRIL SURFACE HEATING ENOUGH TO LIMIT MAX
TEMPS THE UPPER 30S. MODEL 850 MB TEMPERATURES SETTLING INTO THE -13
TO -16C RANGE BY LATE AFTERNOON IS A STRONG ENDORSEMENT ON THE COLD
NATURE OF THE AIR MASS. BOUNDARY LAYER MOISTURE AND INSTABILITY WILL
KEEP PLENTY OF CLOUDS STIRRED UP WHICH WILL FURTHER LIMIT
TEMPERATURES. THERE MAY BE A FEW FLURRIES AS WELL, ALTHOUGH MODEL
SOUNDINGS SHOW THE AIR TO BE ON THE DRY SIDE BELOW CLOUD BASE. THE
MAIN TAKEAWAY IS THAT THE COLD AFTERNOON TEMPERATURES WILL HAVE
READINGS WELL POSITIONED TO MAKE A RUN AT RECORD LOWS TONIGHT. A
SHORT PERIOD OF IDEAL RADIATIONAL COOLING IS EXPECTED TO OCCUR
AROUND MIDNIGHT AFTER VERY LITTLE MELTING OF THE NEW SNOW COVER
DURING THE DAY COMBINED WITH THE DISSIPATION OF LOWER CLOUDS AND
DIMINISHING WIND. EXPECT MIN TEMPS IN THE TEENS TO LOWER 20S BEFORE
HIGH CLOUDS THICKEN AND THE WIND BACKS TO SOUTHWEST TOWARD SUNRISE
WEDNESDAY. SEE CLIMATE SECTION BELOW FOR STATS.

&&

.LONG TERM...

NOT MUCH OF A WARMUP EXPECTED DURING THE EXTENDED PERIOD...WITH EVEN
A LOW CHANCE FOR ADDITIONAL SNOW FRIDAY NIGHT (SEE 00Z GFS).

UPPER LEVEL WAVE/TROUGH CURRENTLY MOVING ONSHORE OF SOUTHERN BRITISH
COLUMBIA/WASHINGTON WILL SWING THROUGH THE NORTHERN PLAINS WEDNESDAY
AND INTO THE WESTERN GREAT LAKES THURSDAY MORNING. TIGHT BAROCLINIC
ZONE WILL RESIDE OVER THE GREAT LAKES REGION...BUT MID LEVEL
FORCING/FGEN LOOKS TO BE RESIDING NORTH OF SOUTHEAST MICHIGAN. A
DRAMATIC WEAKENING TREND LOOKS TO BE TAKING PLACE DURING THURSDAY AS
SYSTEM ENCOUNTERS REMNANT UPPER LEVEL CONFLUENT FLOW FROM DEPARTING
VORTEX OVER HUDSON BAY.

POTENT PV ANOMALY RETROGRADING THROUGH CENTRAL CANADA DURING THE MID
WEEK PERIOD WILL BE KEY PLAYER AS WE END THE WORK WEEK...WITH
CANADIAN/GFS/EURO ALL SHOWING SUBSTANTIAL TIMING ISSUES...ALONG WITH
THE ISSUES DEALING WITH THE INTERACTION OF THE SOUTHERN ENERGY
COMING OUT OF THE FOUR CORNERS REGION. GFS INDICATING THE OPTIMAL
INTERACTION/PHASING...AND THUS WOULD SUPPORT RAIN CHANGING OVER TO
WET SNOW FRIDAY NIGHT. 00Z EURO/CANADIAN BOTH KEEPING A BIT MORE
WAVE SEPARATION...AND THUS MORE PROGRESSIVE AND NON-PHASED
SOLUTIONS.

&&

.MARINE...

NORTHWEST WINDS OF 20 TO 30 KNOTS TODAY WILL BE COMMON AS COLD
AIRMASS WILL BE IN PLACE. GUSTS COULD EVEN BRIEFLY REACH GALES OVER
THE OPEN WATERS OF LAKE HURON DURING THE AFTERNOON. SIGNIFICANT WAVE
HEIGHTS WILL BUILD TO 7 FEET OR HIGHER OVER THE OPEN WATERS OF
CENTRAL LAKE HURON AND WILL BE IN EXCESS OF 4 FEET ALONG THE EXPOSED
NEARSHORE WATERS OF THE THUMB. THIS IN COMBINATION WITH FREQUENT
GUSTS OF 25 KNOTS SUPPORTS CONTINUANCE OF THE SMALL CRAFT ADVISORIES
FOR LAKE HURON. WINDS AND WAVES WILL QUICKLY SUBSIDE WITH THE
ARRIVAL OF HIGH PRESSURE TONIGHT. THIS HIGH WILL SLOWLY SLIDE EAST
ON WEDNESDAY...LEADING TO INCREASING SOUTHEAST WINDS INTO WEDNESDAY
NIGHT...BUT STILL REMAINING BELOW 30 KNOTS.

&&

.CLIMATE...

SNOWIEST WINTER SEASON (NOT INCLUDING NEW SNOW TODAY)

CITY       2013-2014        RECORD        TO TIE RECORD

FLINT       82.6"      82.9" (1974-75)         0.3"
DETROIT     91.7"      93.6" (1880-81)         1.9"

RECORD LOW MAX TEMPERATURE FOR APRIL 15:

DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

RECORD MINS FOR APRIL 16:

DTW 17 (1875)
FNT 21 (1935)
MBS 21 (1935)


&&

.AVIATION...ISSUED 1253 AM EDT TUE APR 15 2014

//DISCUSSION...

THE COLD AIR HAS PUSHED SOUTHEAST ALL THE WAY THROUGH DETROIT
COMPLETING THE CHANGEOVER FROM RAIN TO SNOW. IFR CIGS AND VSBYS HAVE
SET IN AND MAY DIP INTO LIFR DURING THE HEAVIEST SNOWFALL. SNOW WILL
TAPER OFF AROUND 10Z WITH IMPROVING CONDITIONS QUICKLY FOLLOWING AS
HIGH PRESSURE BUILDS IN. NORTHWEST WINDS WILL PREVAIL THROUGH THE
FORECAST AND SPEEDS WILL STAY ELEVATED...AROUND 10 TO 15 KNOTS THE
REST OF THE NIGHT WITH A TIGHT PRESSURE GRADIENT IN PLACE. GUSTY
WINDS WILL AGAIN DEVELOP THIS AFTERNOON AS WE MIX BACK UP TO AROUND
750MB. THE AFOREMENTIONED HIGH WILL ALLOW WINDS TO RELAX BELOW 10
KNOTS TUESDAY NIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET THROUGH THIS MORNING.

* HIGH CONFIDENCE PRECIPITATION TYPE WILL BE SNOW TONIGHT.

* LOW CONFIDENCE VISIBILITY WILL FALL BELOW 1/2SM EARLY THIS
MORNING.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL MIDNIGHT WEDNESDAY.

LAKE ST CLAIR...NONE.

MI WATERS OF LAKE ERIE...NONE.

&&

$$

SHORT TERM...BT
LONG TERM....SF
MARINE.......SF
CLIMATE......BT/SF
AVIATION.....DRK


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










000
FXUS63 KDTX 150453
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1253 AM EDT TUE APR 15 2014

.AVIATION...

//DISCUSSION...

THE COLD AIR HAS PUSHED SOUTHEAST ALL THE WAY THROUGH DETROIT
COMPLETING THE CHANGEOVER FROM RAIN TO SNOW. IFR CIGS AND VSBYS HAVE
SET IN AND MAY DIP INTO LIFR DURING THE HEAVIEST SNOWFALL. SNOW WILL
TAPER OFF AROUND 10Z WITH IMPROVING CONDITIONS QUICKLY FOLLOWING AS
HIGH PRESSURE BUILDS IN. NORTHWEST WINDS WILL PREVAIL THROUGH THE
FORECAST AND SPEEDS WILL STAY ELEVATED...AROUND 10 TO 15 KNOTS THE
REST OF THE NIGHT WITH A TIGHT PRESSURE GRADIENT IN PLACE. GUSTY
WINDS WILL AGAIN DEVELOP THIS AFTERNOON AS WE MIX BACK UP TO AROUND
750MB. THE AFOREMENTIONED HIGH WILL ALLOW WINDS TO RELAX BELOW 10
KNOTS TUESDAY NIGHT.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET THROUGH THIS MORNING.

* HIGH CONFIDENCE PRECIPITATION TYPE WILL BE SNOW TONIGHT.

* LOW CONFIDENCE VISIBILITY WILL FALL BELOW 1/2SM EARLY THIS
MORNING.

&&

.PREV DISCUSSION...ISSUED 947 PM EDT MON APR 14 2014

UPDATE...
WE HAVE TO AREAS OF PRECIPITATION HEADING INTO THE AREA. A 700MB
FGEN BAND WORKING EAST THROUGH SW MI AND A SHORTWAVE TRACKING
NORTH FROM TENNESSEE. THE FGEN BAND IS DRIFTING EAST BUT THE
FORCING AND MOISTURE ARE SHEARING NE INTO NORTHERN MI AWAY FROM
THE AREA. REPORT FROM GRR HAD 1.5 INCHES OF SNOW THUS FAR IN
NEWAYGO CO. WITH QPF LESSENING AS IT
APPROACHES AND LOTS OF STANDING WATER TO ABSORB THE SNOW...MIDLAND/BAY/SAGINAW
SHOULD MISS OUT ON THESE TOTALS BUT UP TO AN INCH STILL SEEMS
REASONABLE. THE OTHER AREA OF INTEREST WILL AFFECT THE EASTERN
PORTION OF THE CWA OVERNIGHT. TEMPS ARE STILL ABOVE FREEZING AND
FALLING BUT THIS WILL YIELD A FEW HOURS OF LIGHT RAIN OR MIXED
PRECIP BEFORE THE CHANGEOVER. HIGHRES MODELS STILL COMING IN WITH
AROUND 0.3-0.4 INCHES OF QPF WHICH HAS BEEN PRETTY CONSISTENT.
THERE IS A CONVECTIVE NATURE TO THE STORM WITH A FEW LIGHTNING
STRIKES OCCURRING. WHETHER WE HAVE LIGHTNING OR NOT
HERE...CONVECTION WILL HELP WITH INCREASING RATES FOR A FEW HOURS
IF IT LASTS INTO SE MI...MOST LIKELY BETWEEN 05-09Z. STILL AGREE
WITH AROUND 1-3 INCHES OF SNOW BY TUESDAY MORNING FOR LOCATIONS
EAST OF A LINE FROM BAD AXE TO FLINT TO ADRIAN.

PREV DISCUSSION...ISSUED 321 PM EDT MON APR 14 2014

SHORT TERM...THROUGH THIS EVENING

SURFACE LOW PRESSURE AT 990 MB HAS ROCKETED NORTHEASTWARD TO FAR
WESTERN QUEBEC. INITIAL LOW LEVEL COLD AIR ADVECTION IS UNDERWAY IN
THE WAKE OF THE COLD FRONT...WITH A HIGH AMOUNT OF STABILITY HAVING
DEVELOPED IN THE 2-4 KFT AGL LAYER. THIS STABILITY HAS DAMPENED THE
WIND RESPONSE WITH WINDSPEEDS NOW IN THE 15 TO 30 MPH RANGE. EXPECT
THIS TO LARGELY HOLD NOW INTO THE EARLY EVENING HOURS. THE SURFACE
TEMPERATURE RESPONSE HAS BEEN NOTEWORTHY...READINGS OUTSIDE NOW 20
DEGREES COOLER THAN HIGHS ACHIEVED THIS MORNING.

LONG TERM...

FLOW AROUND THE SOUTHERN PERIPHERY OF THE CENTRAL U.S. TROUGH WILL
BECOME INCREASINGLY CONSOLIDATED OVER THE NEXT SEVERAL HOURS AS THE
SOUTHERN STREAM SHORTWAVE OVER THE LOWER GREAT PLAINS BECOMES
INCREASINGLY SHEARED AND ABSORBED INTO THE PREVAILING SOUTHWEST
FLOW. AS THIS OCCURS, THE UPPER TROUGH WILL TRANSITION TO A MORE
NEUTRAL TILT AND THE MASS GRADIENT WILL STRENGTHEN CONSIDERABLY,
ELICITING AN IMPRESSIVE JET RESPONSE. THIS JETLET WILL PROPAGATE
RAPIDLY NORTHEAST, TRAVERSING THE GREAT LAKES 03-09Z. AT THE SAME
TIME, STRONG COLD ADVECTION WILL BE ONGOING AND DEEPENING WITH TIME
IN THE LOW-LEVELS IN THE WAKE OF THIS AFTERNOON`S SURFACE COLD
FRONT. THE H7 PORTION OF THE FRONTAL SLOPE, ALREADY SHOWING SIGNS OF
LIFE FROM SE KANSAS INTO NW ILLINOIS WILL REMAIN ACTIVE AS IT SLIDES
EAST WITH THE MAIN UPPER TROUGH, BRINGING LIGHT TO MODERATE SNOW TO
NORTHWESTERN PORTIONS OF THE AREA.

MEANWHILE, EXTREMELY LOW STATIC STABILITY COMBINED WITH POTENTIAL
FOR UPRIGHT INSTABILITY WILL STRONGLY FAVOR A LOWER PORTION OF THE
FRONTAL SLOPE BECOMING ACTIVE AS FORCING ASSOCIATED WITH THE
AFOREMENTIONED JET RACES INTO THE AREA FROM THE SOUTHWEST. THE BIG
QUESTION THEN BECOMES EXACT PLACEMENT AND JUST HOW QUICKLY THE
COLUMN COOLS, ESPECIALLY FOR SOUTHEASTERN AREAS, INCLUDING METRO
DETROIT. SYNOPTICALLY, ALL LOCATIONS SHOULD CHANGE TO SNOW BY 05Z,
WITH THE METRO AREA CHANGING OVER LAST. THIS EXPECTATION IS
COMPLICATED, HOWEVER, BY THE FACT THAT POTENTIALLY VERY STRONG
ASCENT WILL AID IN COOLING THE COLUMN AND MAY ALLOW AN EARLIER
CHANGEOVER DURING THE HEAVIEST PRECIPITATION. IN ADDITION, THE
POTENTIAL FOR CONVECTION INTRODUCES BOTH THE POTENTIAL FOR
OVERACHIEVING FROM THE METRO AREA SOUTHWARD AS WELL AS THE POTENTIAL
FOR THE RESULTANT LATENT HEATING TO WARM THE COLUMN ABOVE FREEZING.
UNFORTUNATELY, IT APPEARS THAT EVALUATION OF THE EXACT NATURE OF
PRECIP OVER THE AFOREMENTIONED AREA WILL HAVE TO BE AN ONGOING
PROCESSES THIS EVENING. WILL THEREFORE FAVOR A MIDDLE-OF-THE-ROAD
FORECAST FOR ACCUMS TO ALLOW FOR LATER REFINEMENTS EITHER UP OR DOWN.

AS FOR FORECAST AMOUNTS, WEAKER FORCING AND A WET GROUND/STANDING
WATER WILL LIMIT SNOW RATIOS INVOF THE SAGINAW VALLEY. ELSEWHERE,
FAVORABLE NOCTURNAL TIMING, DRIER GROUND, AND HIGHER SNOWFALL RATES
WILL FAVOR SOMETHING CLOSER TO 12:1. GENERALLY EXPECTING AMOUNTS TO
RANGE FROM AROUND AN INCH IN THE SAGINAW VALLEY TO 3 INCHES FROM THE
METRO AREA SOUTH. COULD CERTAINLY SEE SNOWFALL RATES ON THE ORDER OF
AN INCH PER HOUR ACCOMPANIED BY THUNDER ON A LOCAL BASIS. FOLLOWED
AN ARW/NMM BLEND FOR QPF AMOUNTS DUE TO GENERAL CONSENSUS WITH
LARGER SCALE MODELS AND THEIR SIMILAR HANDING OF FINE SCALE
FEATURES, PARTICULARLY INVOF THE METROPOLITIAN AREA. THE FORECAST IN
ITS CURRENT FORM CALLS FOR BREAKING THE ALL-TIME RECORDS FOR
SNOWIEST WINTER SEASON AT BOTH DETROIT AND FLINT (SEE CLIMATE
SECTION).

COLD AIR CHARACTERIZED BY H85 TEMPS AROUND -13C WILL BE FIRMLY
ENTRENCHED FOR THE BALANCE OF THE DAY ON TUESDAY. DAYTIME HEATING
WILL SUPPORT AN EXPANSION OF BOUNDARY LAYER CLOUD COVER AND
SUPERSATURATION SUPPORTIVE OF FLURRIES OR SNOW SHOWERS. BUILDING
HIGH PRESSURE AND REBOUNDING HEIGHTS ALOFT WILL FAVOR CLEARING AND
COLD TEMPERATURES ON TUESDAY NIGHT. TEMPERATURES WILL REBOUND A
SOLID 10 DEGREES BY WEDNESDAY UNDER SHORTWAVE RIDGING AND AND A
DEVELOPING SOUTHEAST GRADIENT IN ADVANCE OF LOW PRESSURE OVER THE
UPPER MS VALLEY.

THE WEEKEND WILL FEATURE TURBULENT UPPER LEVEL FLOW WITH TWO
UPPER LEVEL WAVES TRAVERSING THE EASTER 2/3 OF THE CONUS. THIS
WILL BRING SEVERAL BOUTS OF LIGHT RAIN SHOWERS OVER THE WEEKEND.
TEMPERATURES WILL HOVER JUST UNDER THE CLIMO NORMS FOR THE PERIOD.
HIGH PRESSURE SHOULD DRY THINGS OUT FOR EARLY NEXT WEEK.

MARINE...

MODERATE TO FRESH NORTHWEST WINDS WILL BECOME INCREASINGLY GUSTY AS
COLD AIR POURS INTO THE AREA TONIGHT INTO TUESDAY. GUSTS WILL
APPROACH NEAR GALES AT TIMES DURING THE AFTERNOON. SIGNIFICANT WAVE
HEIGHTS WILL BUILD TO 7 FEET OR HIGHER OVER THE OPEN WATERS OF
CENTRAL LAKE HURON AND WILL BE IN EXCESS OF 4 FEET ALONG THE EXPOSED
NEARSHORE WATERS OF THE THUMB. THIS IN COMBINATION WITH FREQUENT
GUSTS OF 25 KNOTS SUPPORTS CONTINUANCE OF THE SMALL CRAFT ADVISORIES
FOR LAKE HURON. WINDS AND WAVES WILL SUBSIDE WITH THE ARRIVAL OF
HIGH PRESSURE ON TUESDAY NIGHT.

CLIMATE...

SNOWIEST WINTER SEASON

CITY       2013-2014        RECORD        TO TIE RECORD
FLINT       82.6"      82.9" (1974-75)         0.3"
DETROIT     91.7"      93.6" (1880-81)         1.9"

RECORD LOW HIGH TEMPERATURE FOR APRIL 15:
DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...NONE.

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL 4 PM TUESDAY.

LAKE ST CLAIR...NONE.

MI WATERS OF LAKE ERIE...NONE.

&&

$$

AVIATION.....DRK
UPDATE.......DRK
SHORT TERM...CB
LONG TERM....JVC/MM
MARINE.......JVC
CLIMATE......JVC


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









000
FXUS63 KDTX 150147
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
947 PM EDT MON APR 14 2014

.UPDATE...
WE HAVE TO AREAS OF PRECIPITATION HEADING INTO THE AREA. A 700MB
FGEN BAND WORKING EAST THROUGH SW MI AND A SHORTWAVE TRACKING
NORTH FROM TENNESSEE. THE FGEN BAND IS DRIFTING EAST BUT THE
FORCING AND MOISTURE ARE SHEARING NE INTO NORTHERN MI AWAY FROM
THE AREA. REPORT FROM GRR HAD 1.5 INCHES OF SNOW THUS FAR IN
NEWAYGO CO. WITH QPF LESSENING AS IT
APPROACHES AND LOTS OF STANDING WATER TO ABSORB THE SNOW...MIDLAND/BAY/SAGINAW
SHOULD MISS OUT ON THESE TOTALS BUT UP TO AN INCH STILL SEEMS
REASONABLE. THE OTHER AREA OF INTEREST WILL AFFECT THE EASTERN
PORTION OF THE CWA OVERNIGHT. TEMPS ARE STILL ABOVE FREEZING AND
FALLING BUT THIS WILL YIELD A FEW HOURS OF LIGHT RAIN OR MIXED
PRECIP BEFORE THE CHANGEOVER. HIGHRES MODELS STILL COMING IN WITH
AROUND 0.3-0.4 INCHES OF QPF WHICH HAS BEEN PRETTY CONSISTENT.
THERE IS A CONVECTIVE NATURE TO THE STORM WITH A FEW LIGHTNING
STRIKES OCCURRING. WHETHER WE HAVE LIGHTNING OR NOT
HERE...CONVECTION WILL HELP WITH INCREASING RATES FOR A FEW HOURS
IF IT LASTS INTO SE MI...MOST LIKELY BETWEEN 05-09Z. STILL AGREE
WITH AROUND 1-3 INCHES OF SNOW BY TUESDAY MORNING FOR LOCATIONS
EAST OF A LINE FROM BAD AXE TO FLINT TO ADRIAN.

&&

.AVIATION...ISSUED 759 PM EDT MON APR 14 2014

//DISCUSSION...

THE NEXT LOW PRESSURE SYSTEM IS SURGING NORTH FROM THE LOWER
MISSISSIPPI VALLEY. THIS WILL BRING A PERIOD OF SNOW TO THE REGION
STARTING AROUND 03Z AND TAPERING OFF AROUND 10Z TUESDAY MORNING.
MODELS CONTINUE TO ADVERTISE HIGHER RATES FOR SEVERAL HOURS AS GOOD
FORCING ALOFT ADVECTS OVER THE REGION. THIS WILL RESULT IN IFR/LIFR
CONDITIONS WITH ACCUMULATIONS UP TO A FEW INCHES BY MORNING. WINDS
WILL STAY SLIGHTLY ELEVATED...AROUND 12 KNOTS...THROUGH THE NIGHT AS
PRESSURE GRADIENT TIGHTEN OVER THE STATE. GUSTS WILL REACH NEAR 25
KNOTS TOMORROW AFTERNOON BEFORE HIGH PRESSURE BUILDS IN ALLOW THEM
TO RELAX.

FOR DTW...CONFIDENCE IS HIGH IN A BURST OF MODERATE TO HEAVY
SNOWFALL TONIGHT. THE OVERALL POTENTIAL FOR ACCUMULATION ON PAVED
SURFACES REMAINS UNKNOWN.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET THROUGH TUESDAY MORNING.

* HIGH CONFIDENCE PRECIPITATION TYPE WILL BE SNOW TONIGHT.

&&

.PREV DISCUSSION...ISSUED 321 PM EDT MON APR 14 2014

SHORT TERM...THROUGH THIS EVENING

SURFACE LOW PRESSURE AT 990 MB HAS ROCKETED NORTHEASTWARD TO FAR
WESTERN QUEBEC. INITIAL LOW LEVEL COLD AIR ADVECTION IS UNDERWAY IN
THE WAKE OF THE COLD FRONT...WITH A HIGH AMOUNT OF STABILITY HAVING
DEVELOPED IN THE 2-4 KFT AGL LAYER. THIS STABILITY HAS DAMPENED THE
WIND RESPONSE WITH WINDSPEEDS NOW IN THE 15 TO 30 MPH RANGE. EXPECT
THIS TO LARGELY HOLD NOW INTO THE EARLY EVENING HOURS. THE SURFACE
TEMPERATURE RESPONSE HAS BEEN NOTEWORTHY...READINGS OUTSIDE NOW 20
DEGREES COOLER THAN HIGHS ACHIEVED THIS MORNING.

LONG TERM...

FLOW AROUND THE SOUTHERN PERIPHERY OF THE CENTRAL U.S. TROUGH WILL
BECOME INCREASINGLY CONSOLIDATED OVER THE NEXT SEVERAL HOURS AS THE
SOUTHERN STREAM SHORTWAVE OVER THE LOWER GREAT PLAINS BECOMES
INCREASINGLY SHEARED AND ABSORBED INTO THE PREVAILING SOUTHWEST
FLOW. AS THIS OCCURS, THE UPPER TROUGH WILL TRANSITION TO A MORE
NEUTRAL TILT AND THE MASS GRADIENT WILL STRENGTHEN CONSIDERABLY,
ELICITING AN IMPRESSIVE JET RESPONSE. THIS JETLET WILL PROPAGATE
RAPIDLY NORTHEAST, TRAVERSING THE GREAT LAKES 03-09Z. AT THE SAME
TIME, STRONG COLD ADVECTION WILL BE ONGOING AND DEEPENING WITH TIME
IN THE LOW-LEVELS IN THE WAKE OF THIS AFTERNOON`S SURFACE COLD
FRONT. THE H7 PORTION OF THE FRONTAL SLOPE, ALREADY SHOWING SIGNS OF
LIFE FROM SE KANSAS INTO NW ILLINOIS WILL REMAIN ACTIVE AS IT SLIDES
EAST WITH THE MAIN UPPER TROUGH, BRINGING LIGHT TO MODERATE SNOW TO
NORTHWESTERN PORTIONS OF THE AREA.

MEANWHILE, EXTREMELY LOW STATIC STABILITY COMBINED WITH POTENTIAL
FOR UPRIGHT INSTABILITY WILL STRONGLY FAVOR A LOWER PORTION OF THE
FRONTAL SLOPE BECOMING ACTIVE AS FORCING ASSOCIATED WITH THE
AFOREMENTIONED JET RACES INTO THE AREA FROM THE SOUTHWEST. THE BIG
QUESTION THEN BECOMES EXACT PLACEMENT AND JUST HOW QUICKLY THE
COLUMN COOLS, ESPECIALLY FOR SOUTHEASTERN AREAS, INCLUDING METRO
DETROIT. SYNOPTICALLY, ALL LOCATIONS SHOULD CHANGE TO SNOW BY 05Z,
WITH THE METRO AREA CHANGING OVER LAST. THIS EXPECTATION IS
COMPLICATED, HOWEVER, BY THE FACT THAT POTENTIALLY VERY STRONG
ASCENT WILL AID IN COOLING THE COLUMN AND MAY ALLOW AN EARLIER
CHANGEOVER DURING THE HEAVIEST PRECIPITATION. IN ADDITION, THE
POTENTIAL FOR CONVECTION INTRODUCES BOTH THE POTENTIAL FOR
OVERACHIEVING FROM THE METRO AREA SOUTHWARD AS WELL AS THE POTENTIAL
FOR THE RESULTANT LATENT HEATING TO WARM THE COLUMN ABOVE FREEZING.
UNFORTUNATELY, IT APPEARS THAT EVALUATION OF THE EXACT NATURE OF
PRECIP OVER THE AFOREMENTIONED AREA WILL HAVE TO BE AN ONGOING
PROCESSES THIS EVENING. WILL THEREFORE FAVOR A MIDDLE-OF-THE-ROAD
FORECAST FOR ACCUMS TO ALLOW FOR LATER REFINEMENTS EITHER UP OR DOWN.

AS FOR FORECAST AMOUNTS, WEAKER FORCING AND A WET GROUND/STANDING
WATER WILL LIMIT SNOW RATIOS INVOF THE SAGINAW VALLEY. ELSEWHERE,
FAVORABLE NOCTURNAL TIMING, DRIER GROUND, AND HIGHER SNOWFALL RATES
WILL FAVOR SOMETHING CLOSER TO 12:1. GENERALLY EXPECTING AMOUNTS TO
RANGE FROM AROUND AN INCH IN THE SAGINAW VALLEY TO 3 INCHES FROM THE
METRO AREA SOUTH. COULD CERTAINLY SEE SNOWFALL RATES ON THE ORDER OF
AN INCH PER HOUR ACCOMPANIED BY THUNDER ON A LOCAL BASIS. FOLLOWED
AN ARW/NMM BLEND FOR QPF AMOUNTS DUE TO GENERAL CONSENSUS WITH
LARGER SCALE MODELS AND THEIR SIMILAR HANDING OF FINE SCALE
FEATURES, PARTICULARLY INVOF THE METROPOLITIAN AREA. THE FORECAST IN
ITS CURRENT FORM CALLS FOR BREAKING THE ALL-TIME RECORDS FOR
SNOWIEST WINTER SEASON AT BOTH DETROIT AND FLINT (SEE CLIMATE
SECTION).

COLD AIR CHARACTERIZED BY H85 TEMPS AROUND -13C WILL BE FIRMLY
ENTRENCHED FOR THE BALANCE OF THE DAY ON TUESDAY. DAYTIME HEATING
WILL SUPPORT AN EXPANSION OF BOUNDARY LAYER CLOUD COVER AND
SUPERSATURATION SUPPORTIVE OF FLURRIES OR SNOW SHOWERS. BUILDING
HIGH PRESSURE AND REBOUNDING HEIGHTS ALOFT WILL FAVOR CLEARING AND
COLD TEMPERATURES ON TUESDAY NIGHT. TEMPERATURES WILL REBOUND A
SOLID 10 DEGREES BY WEDNESDAY UNDER SHORTWAVE RIDGING AND AND A
DEVELOPING SOUTHEAST GRADIENT IN ADVANCE OF LOW PRESSURE OVER THE
UPPER MS VALLEY.

THE WEEKEND WILL FEATURE TURBULENT UPPER LEVEL FLOW WITH TWO
UPPER LEVEL WAVES TRAVERSING THE EASTER 2/3 OF THE CONUS. THIS
WILL BRING SEVERAL BOUTS OF LIGHT RAIN SHOWERS OVER THE WEEKEND.
TEMPERATURES WILL HOVER JUST UNDER THE CLIMO NORMS FOR THE PERIOD.
HIGH PRESSURE SHOULD DRY THINGS OUT FOR EARLY NEXT WEEK.

MARINE...

MODERATE TO FRESH NORTHWEST WINDS WILL BECOME INCREASINGLY GUSTY AS
COLD AIR POURS INTO THE AREA TONIGHT INTO TUESDAY. GUSTS WILL
APPROACH NEAR GALES AT TIMES DURING THE AFTERNOON. SIGNIFICANT WAVE
HEIGHTS WILL BUILD TO 7 FEET OR HIGHER OVER THE OPEN WATERS OF
CENTRAL LAKE HURON AND WILL BE IN EXCESS OF 4 FEET ALONG THE EXPOSED
NEARSHORE WATERS OF THE THUMB. THIS IN COMBINATION WITH FREQUENT
GUSTS OF 25 KNOTS SUPPORTS CONTINUANCE OF THE SMALL CRAFT ADVISORIES
FOR LAKE HURON. WINDS AND WAVES WILL SUBSIDE WITH THE ARRIVAL OF
HIGH PRESSURE ON TUESDAY NIGHT.

CLIMATE...

SNOWIEST WINTER SEASON

CITY       2013-2014        RECORD        TO TIE RECORD
FLINT       82.6"      82.9" (1974-75)         0.3"
DETROIT     91.7"      93.6" (1880-81)         1.9"

RECORD LOW HIGH TEMPERATURE FOR APRIL 15:
DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

&&

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

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL 4 PM TUESDAY.

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

&&

$$

UPDATE.......DRK
AVIATION.....DRK
SHORT TERM...CB
LONG TERM....JVC/MM
MARINE.......JVC
CLIMATE......JVC
CLIMATE......DRK


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








000
FXUS63 KDTX 142359
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
759 PM EDT MON APR 14 2014


.AVIATION...

//DISCUSSION...

THE NEXT LOW PRESSURE SYSTEM IS SURGING NORTH FROM THE LOWER
MISSISSIPPI VALLEY. THIS WILL BRING A PERIOD OF SNOW TO THE REGION
STARTING AROUND 03Z AND TAPERING OFF AROUND 10Z TUESDAY MORNING.
MODELS CONTINUE TO ADVERTISE HIGHER RATES FOR SEVERAL HOURS AS GOOD
FORCING ALOFT ADVECTS OVER THE REGION. THIS WILL RESULT IN IFR/LIFR
CONDITIONS WITH ACCUMULATIONS UP TO A FEW INCHES BY MORNING. WINDS
WILL STAY SLIGHTLY ELEVATED...AROUND 12 KNOTS...THROUGH THE NIGHT AS
PRESSURE GRADIENT TIGHTEN OVER THE STATE. GUSTS WILL REACH NEAR 25
KNOTS TOMORROW AFTERNOON BEFORE HIGH PRESSURE BUILDS IN ALLOW THEM
TO RELAX.

FOR DTW...CONFIDENCE IS HIGH IN A BURST OF MODERATE TO HEAVY
SNOWFALL TONIGHT. THE OVERALL POTENTIAL FOR ACCUMULATION ON PAVED
SURFACES REMAINS UNKNOWN.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET THROUGH TUESDAY MORNING.

* HIGH CONFIDENCE PRECIPITATION TYPE WILL BE SNOW TONIGHT.

&&

.PREV DISCUSSION...ISSUED 321 PM EDT MON APR 14 2014

SHORT TERM...THROUGH THIS EVENING

SURFACE LOW PRESSURE AT 990 MB HAS ROCKETED NORTHEASTWARD TO FAR
WESTERN QUEBEC. INITIAL LOW LEVEL COLD AIR ADVECTION IS UNDERWAY IN
THE WAKE OF THE COLD FRONT...WITH A HIGH AMOUNT OF STABILITY HAVING
DEVELOPED IN THE 2-4 KFT AGL LAYER. THIS STABILITY HAS DAMPENED THE
WIND RESPONSE WITH WINDSPEEDS NOW IN THE 15 TO 30 MPH RANGE. EXPECT
THIS TO LARGELY HOLD NOW INTO THE EARLY EVENING HOURS. THE SURFACE
TEMPERATURE RESPONSE HAS BEEN NOTEWORTHY...READINGS OUTSIDE NOW 20
DEGREES COOLER THAN HIGHS ACHIEVED THIS MORNING.

LONG TERM...

FLOW AROUND THE SOUTHERN PERIPHERY OF THE CENTRAL U.S. TROUGH WILL
BECOME INCREASINGLY CONSOLIDATED OVER THE NEXT SEVERAL HOURS AS THE
SOUTHERN STREAM SHORTWAVE OVER THE LOWER GREAT PLAINS BECOMES
INCREASINGLY SHEARED AND ABSORBED INTO THE PREVAILING SOUTHWEST
FLOW. AS THIS OCCURS, THE UPPER TROUGH WILL TRANSITION TO A MORE
NEUTRAL TILT AND THE MASS GRADIENT WILL STRENGTHEN CONSIDERABLY,
ELICITING AN IMPRESSIVE JET RESPONSE. THIS JETLET WILL PROPAGATE
RAPIDLY NORTHEAST, TRAVERSING THE GREAT LAKES 03-09Z. AT THE SAME
TIME, STRONG COLD ADVECTION WILL BE ONGOING AND DEEPENING WITH TIME
IN THE LOW-LEVELS IN THE WAKE OF THIS AFTERNOON`S SURFACE COLD
FRONT. THE H7 PORTION OF THE FRONTAL SLOPE, ALREADY SHOWING SIGNS OF
LIFE FROM SE KANSAS INTO NW ILLINOIS WILL REMAIN ACTIVE AS IT SLIDES
EAST WITH THE MAIN UPPER TROUGH, BRINGING LIGHT TO MODERATE SNOW TO
NORTHWESTERN PORTIONS OF THE AREA.

MEANWHILE, EXTREMELY LOW STATIC STABILITY COMBINED WITH POTENTIAL
FOR UPRIGHT INSTABILITY WILL STRONGLY FAVOR A LOWER PORTION OF THE
FRONTAL SLOPE BECOMING ACTIVE AS FORCING ASSOCIATED WITH THE
AFOREMENTIONED JET RACES INTO THE AREA FROM THE SOUTHWEST. THE BIG
QUESTION THEN BECOMES EXACT PLACEMENT AND JUST HOW QUICKLY THE
COLUMN COOLS, ESPECIALLY FOR SOUTHEASTERN AREAS, INCLUDING METRO
DETROIT. SYNOPTICALLY, ALL LOCATIONS SHOULD CHANGE TO SNOW BY 05Z,
WITH THE METRO AREA CHANGING OVER LAST. THIS EXPECTATION IS
COMPLICATED, HOWEVER, BY THE FACT THAT POTENTIALLY VERY STRONG
ASCENT WILL AID IN COOLING THE COLUMN AND MAY ALLOW AN EARLIER
CHANGEOVER DURING THE HEAVIEST PRECIPITATION. IN ADDITION, THE
POTENTIAL FOR CONVECTION INTRODUCES BOTH THE POTENTIAL FOR
OVERACHIEVING FROM THE METRO AREA SOUTHWARD AS WELL AS THE POTENTIAL
FOR THE RESULTANT LATENT HEATING TO WARM THE COLUMN ABOVE FREEZING.
UNFORTUNATELY, IT APPEARS THAT EVALUATION OF THE EXACT NATURE OF
PRECIP OVER THE AFOREMENTIONED AREA WILL HAVE TO BE AN ONGOING
PROCESSES THIS EVENING. WILL THEREFORE FAVOR A MIDDLE-OF-THE-ROAD
FORECAST FOR ACCUMS TO ALLOW FOR LATER REFINEMENTS EITHER UP OR DOWN.

AS FOR FORECAST AMOUNTS, WEAKER FORCING AND A WET GROUND/STANDING
WATER WILL LIMIT SNOW RATIOS INVOF THE SAGINAW VALLEY. ELSEWHERE,
FAVORABLE NOCTURNAL TIMING, DRIER GROUND, AND HIGHER SNOWFALL RATES
WILL FAVOR SOMETHING CLOSER TO 12:1. GENERALLY EXPECTING AMOUNTS TO
RANGE FROM AROUND AN INCH IN THE SAGINAW VALLEY TO 3 INCHES FROM THE
METRO AREA SOUTH. COULD CERTAINLY SEE SNOWFALL RATES ON THE ORDER OF
AN INCH PER HOUR ACCOMPANIED BY THUNDER ON A LOCAL BASIS. FOLLOWED
AN ARW/NMM BLEND FOR QPF AMOUNTS DUE TO GENERAL CONSENSUS WITH
LARGER SCALE MODELS AND THEIR SIMILAR HANDING OF FINE SCALE
FEATURES, PARTICULARLY INVOF THE METROPOLITIAN AREA. THE FORECAST IN
ITS CURRENT FORM CALLS FOR BREAKING THE ALL-TIME RECORDS FOR
SNOWIEST WINTER SEASON AT BOTH DETROIT AND FLINT (SEE CLIMATE
SECTION).

COLD AIR CHARACTERIZED BY H85 TEMPS AROUND -13C WILL BE FIRMLY
ENTRENCHED FOR THE BALANCE OF THE DAY ON TUESDAY. DAYTIME HEATING
WILL SUPPORT AN EXPANSION OF BOUNDARY LAYER CLOUD COVER AND
SUPERSATURATION SUPPORTIVE OF FLURRIES OR SNOW SHOWERS. BUILDING
HIGH PRESSURE AND REBOUNDING HEIGHTS ALOFT WILL FAVOR CLEARING AND
COLD TEMPERATURES ON TUESDAY NIGHT. TEMPERATURES WILL REBOUND A
SOLID 10 DEGREES BY WEDNESDAY UNDER SHORTWAVE RIDGING AND AND A
DEVELOPING SOUTHEAST GRADIENT IN ADVANCE OF LOW PRESSURE OVER THE
UPPER MS VALLEY.

THE WEEKEND WILL FEATURE TURBULENT UPPER LEVEL FLOW WITH TWO
UPPER LEVEL WAVES TRAVERSING THE EASTER 2/3 OF THE CONUS. THIS
WILL BRING SEVERAL BOUTS OF LIGHT RAIN SHOWERS OVER THE WEEKEND.
TEMPERATURES WILL HOVER JUST UNDER THE CLIMO NORMS FOR THE PERIOD.
HIGH PRESSURE SHOULD DRY THINGS OUT FOR EARLY NEXT WEEK.

MARINE...

MODERATE TO FRESH NORTHWEST WINDS WILL BECOME INCREASINGLY GUSTY AS
COLD AIR POURS INTO THE AREA TONIGHT INTO TUESDAY. GUSTS WILL
APPROACH NEAR GALES AT TIMES DURING THE AFTERNOON. SIGNIFICANT WAVE
HEIGHTS WILL BUILD TO 7 FEET OR HIGHER OVER THE OPEN WATERS OF
CENTRAL LAKE HURON AND WILL BE IN EXCESS OF 4 FEET ALONG THE EXPOSED
NEARSHORE WATERS OF THE THUMB. THIS IN COMBINATION WITH FREQUENT
GUSTS OF 25 KNOTS SUPPORTS CONTINUANCE OF THE SMALL CRAFT ADVISORIES
FOR LAKE HURON. WINDS AND WAVES WILL SUBSIDE WITH THE ARRIVAL OF
HIGH PRESSURE ON TUESDAY NIGHT.

CLIMATE...

SNOWIEST WINTER SEASON

CITY       2013-2014        RECORD        TO TIE RECORD
FLINT       82.6"      82.9" (1974-75)         0.3"
DETROIT     91.7"      93.6" (1880-81)         1.9"

RECORD LOW HIGH TEMPERATURE FOR APRIL 15:
DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

&&

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

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL 4 PM TUESDAY.

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

&&

$$

AVIATION.....DRK
SHORT TERM...CB
LONG TERM....JVC/MM
MARINE.......JVC
CLIMATE......JVC


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








000
FXUS63 KDTX 141921
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
321 PM EDT MON APR 14 2014

.SHORT TERM...THROUGH THIS EVENING

SURFACE LOW PRESSURE AT 990 MB HAS ROCKETED NORTHEASTWARD TO FAR
WESTERN QUEBEC. INITIAL LOW LEVEL COLD AIR ADVECTION IS UNDERWAY IN
THE WAKE OF THE COLD FRONT...WITH A HIGH AMOUNT OF STABILITY HAVING
DEVELOPED IN THE 2-4 KFT AGL LAYER. THIS STABILITY HAS DAMPENED THE
WIND RESPONSE WITH WINDSPEEDS NOW IN THE 15 TO 30 MPH RANGE. EXPECT
THIS TO LARGELY HOLD NOW INTO THE EARLY EVENING HOURS. THE SURFACE
TEMPERATURE RESPONSE HAS BEEN NOTEWORTHY...READINGS OUTSIDE NOW 20
DEGREES COOLER THAN HIGHS ACHIEVED THIS MORNING.

&&

.LONG TERM...

FLOW AROUND THE SOUTHERN PERIPHERY OF THE CENTRAL U.S. TROUGH WILL
BECOME INCREASINGLY CONSOLIDATED OVER THE NEXT SEVERAL HOURS AS THE
SOUTHERN STREAM SHORTWAVE OVER THE LOWER GREAT PLAINS BECOMES
INCREASINGLY SHEARED AND ABSORBED INTO THE PREVAILING SOUTHWEST
FLOW. AS THIS OCCURS, THE UPPER TROUGH WILL TRANSITION TO A MORE
NEUTRAL TILT AND THE MASS GRADIENT WILL STRENGTHEN CONSIDERABLY,
ELICITING AN IMPRESSIVE JET RESPONSE. THIS JETLET WILL PROPAGATE
RAPIDLY NORTHEAST, TRAVERSING THE GREAT LAKES 03-09Z. AT THE SAME
TIME, STRONG COLD ADVECTION WILL BE ONGOING AND DEEPENING WITH TIME
IN THE LOW-LEVELS IN THE WAKE OF THIS AFTERNOON`S SURFACE COLD
FRONT. THE H7 PORTION OF THE FRONTAL SLOPE, ALREADY SHOWING SIGNS OF
LIFE FROM SE KANSAS INTO NW ILLINOIS WILL REMAIN ACTIVE AS IT SLIDES
EAST WITH THE MAIN UPPER TROUGH, BRINGING LIGHT TO MODERATE SNOW TO
NORTHWESTERN PORTIONS OF THE AREA.

MEANWHILE, EXTREMELY LOW STATIC STABILITY COMBINED WITH POTENTIAL
FOR UPRIGHT INSTABILITY WILL STRONGLY FAVOR A LOWER PORTION OF THE
FRONTAL SLOPE BECOMING ACTIVE AS FORCING ASSOCIATED WITH THE
AFOREMENTIONED JET RACES INTO THE AREA FROM THE SOUTHWEST. THE BIG
QUESTION THEN BECOMES EXACT PLACEMENT AND JUST HOW QUICKLY THE
COLUMN COOLS, ESPECIALLY FOR SOUTHEASTERN AREAS, INCLUDING METRO
DETROIT. SYNOPTICALLY, ALL LOCATIONS SHOULD CHANGE TO SNOW BY 05Z,
WITH THE METRO AREA CHANGING OVER LAST. THIS EXPECTATION IS
COMPLICATED, HOWEVER, BY THE FACT THAT POTENTIALLY VERY STRONG
ASCENT WILL AID IN COOLING THE COLUMN AND MAY ALLOW AN EARLIER
CHANGEOVER DURING THE HEAVIEST PRECIPITATION. IN ADDITION, THE
POTENTIAL FOR CONVECTION INTRODUCES BOTH THE POTENTIAL FOR
OVERACHIEVING FROM THE METRO AREA SOUTHWARD AS WELL AS THE POTENTIAL
FOR THE RESULTANT LATENT HEATING TO WARM THE COLUMN ABOVE FREEZING.
UNFORTUNATELY, IT APPEARS THAT EVALUATION OF THE EXACT NATURE OF
PRECIP OVER THE AFOREMENTIONED AREA WILL HAVE TO BE AN ONGOING
PROCESSES THIS EVENING. WILL THEREFORE FAVOR A MIDDLE-OF-THE-ROAD
FORECAST FOR ACCUMS TO ALLOW FOR LATER REFINEMENTS EITHER UP OR DOWN.

AS FOR FORECAST AMOUNTS, WEAKER FORCING AND A WET GROUND/STANDING
WATER WILL LIMIT SNOW RATIOS INVOF THE SAGINAW VALLEY. ELSEWHERE,
FAVORABLE NOCTURNAL TIMING, DRIER GROUND, AND HIGHER SNOWFALL RATES
WILL FAVOR SOMETHING CLOSER TO 12:1. GENERALLY EXPECTING AMOUNTS TO
RANGE FROM AROUND AN INCH IN THE SAGINAW VALLEY TO 3 INCHES FROM THE
METRO AREA SOUTH. COULD CERTAINLY SEE SNOWFALL RATES ON THE ORDER OF
AN INCH PER HOUR ACCOMPANIED BY THUNDER ON A LOCAL BASIS. FOLLOWED
AN ARW/NMM BLEND FOR QPF AMOUNTS DUE TO GENERAL CONSENSUS WITH
LARGER SCALE MODELS AND THEIR SIMILAR HANDING OF FINE SCALE
FEATURES, PARTICULARLY INVOF THE METROPOLITIAN AREA. THE FORECAST IN
ITS CURRENT FORM CALLS FOR BREAKING THE ALL-TIME RECORDS FOR
SNOWIEST WINTER SEASON AT BOTH DETROIT AND FLINT (SEE CLIMATE
SECTION).

COLD AIR CHARACTERIZED BY H85 TEMPS AROUND -13C WILL BE FIRMLY
ENTRENCHED FOR THE BALANCE OF THE DAY ON TUESDAY. DAYTIME HEATING
WILL SUPPORT AN EXPANSION OF BOUNDARY LAYER CLOUD COVER AND
SUPERSATURATION SUPPORTIVE OF FLURRIES OR SNOW SHOWERS. BUILDING
HIGH PRESSURE AND REBOUNDING HEIGHTS ALOFT WILL FAVOR CLEARING AND
COLD TEMPERATURES ON TUESDAY NIGHT. TEMPERATURES WILL REBOUND A
SOLID 10 DEGREES BY WEDNESDAY UNDER SHORTWAVE RIDGING AND AND A
DEVELOPING SOUTHEAST GRADIENT IN ADVANCE OF LOW PRESSURE OVER THE
UPPER MS VALLEY.

THE WEEKEND WILL FEATURE TURBULENT UPPER LEVEL FLOW WITH TWO
UPPER LEVEL WAVES TRAVERSING THE EASTER 2/3 OF THE CONUS. THIS
WILL BRING SEVERAL BOUTS OF LIGHT RAIN SHOWERS OVER THE WEEKEND.
TEMPERATURES WILL HOVER JUST UNDER THE CLIMO NORMS FOR THE PERIOD.
HIGH PRESSURE SHOULD DRY THINGS OUT FOR EARLY NEXT WEEK.

&&

.MARINE...

MODERATE TO FRESH NORTHWEST WINDS WILL BECOME INCREASINGLY GUSTY AS
COLD AIR POURS INTO THE AREA TONIGHT INTO TUESDAY. GUSTS WILL
APPROACH NEAR GALES AT TIMES DURING THE AFTERNOON. SIGNIFICANT WAVE
HEIGHTS WILL BUILD TO 7 FEET OR HIGHER OVER THE OPEN WATERS OF
CENTRAL LAKE HURON AND WILL BE IN EXCESS OF 4 FEET ALONG THE EXPOSED
NEARSHORE WATERS OF THE THUMB. THIS IN COMBINATION WITH FREQUENT
GUSTS OF 25 KNOTS SUPPORTS CONTINUANCE OF THE SMALL CRAFT ADVISORIES
FOR LAKE HURON. WINDS AND WAVES WILL SUBSIDE WITH THE ARRIVAL OF
HIGH PRESSURE ON TUESDAY NIGHT.

&&

.CLIMATE...

SNOWIEST WINTER SEASON

CITY       2013-2014        RECORD        TO TIE RECORD
FLINT       82.6"      82.9" (1974-75)         0.3"
DETROIT     91.7"      93.6" (1880-81)         1.9"

RECORD LOW HIGH TEMPERATURE FOR APRIL 15:
DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

&&

.AVIATION...ISSUED 245 PM EDT MON APR 14 2014

//DISCUSSION...

THE MAIN SURFACE COLD FRONT HAS PASSED THROUGH SOUTHEASTERN
MICHIGAN. COLDER AND MORE STABLE AIR WILL NOW FILTER INTO THE
REGION ALLOWING WIND SPEEDS TO MARGINALLY EASE DURING THE NEXT
HOUR OR TWO IN THE 20 TO 30 MPH RANGE. THE NEXT WAVE OF LOW
PRESSURE WILL LIFT DUE NORTHWARD THIS EVENING. PRECIPITATION IS
EXPECTED TO OVERSPREAD SOUTHEASTER MICHIGAN AFTER 3Z...PERSISTING
UNTIL AROUND 10Z. IT IS APPEARING MORE LIKELY THAT HIGH
PRECIPITATION INTENSITY WILL BE PRESENT DUE TO LOW STATIC
STABILITY ALOFT. THESE HIGHER PRECIPITATION RATES WILL SUPPORT A
PRECIPITATION TYPE AS ALL SNOW AT THE START. SNOWFALL
ACCUMULATIONS OF A FEW INCHES WILL BE POSSIBLE TONIGHT WITH SOME
ACCUMULATION ON PAVED SURFACES.

FOR DTW...CONFIDENCE IS HIGH IN A BURST OF MODERATE TO HEAVY
SNOWFALL TONIGHT. THE OVERALL POTENTIAL FOR ACCUMULATION ON PAVED
SURFACES REMAINS UNKNOWN.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET TONIGHT.

* MEDIUM CONFIDENCE PRECIPITATION TYPE WILL BE SNOW TONIGHT.

&&

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

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL 4 PM TUESDAY.

LAKE ST CLAIR...
     SMALL CRAFT ADVISORY...UNTIL 4 PM MONDAY.

MI WATERS OF LAKE ERIE...
     SMALL CRAFT ADVISORY...UNTIL 4 PM MONDAY.

&&

$$

SHORT TERM...CB
LONG TERM....JVC/MM
MARINE.......JVC
CLIMATE......JVC
AVIATION.....CB


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








000
FXUS63 KDTX 141846 CCA
AFDDTX

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
245 PM EDT MON APR 14 2014


.AVIATION...

//DISCUSSION...

THE MAIN SURFACE COLD FRONT HAS PASSED THROUGH SOUTHEASTERN
MICHIGAN. COLDER AND MORE STABLE AIR WILL NOW FILTER INTO THE
REGION ALLOWING WIND SPEEDS TO MARGINALLY EASE DURING THE NEXT
HOUR OR TWO IN THE 20 TO 30 MPH RANGE. THE NEXT WAVE OF LOW
PRESSURE WILL LIFT DUE NORTHWARD THIS EVENING. PRECIPITATION IS
EXPECTED TO OVERSPREAD SOUTHEASTER MICHIGAN AFTER 3Z...PERSISTING
UNTIL AROUND 10Z. IT IS APPEARING MORE LIKELY THAT HIGH
PRECIPITATION INTENSITY WILL BE PRESENT DUE TO LOW STATIC
STABILITY ALOFT. THESE HIGHER PRECIPITATION RATES WILL SUPPORT A
PRECIPITATION TYPE AS ALL SNOW AT THE START. SNOWFALL
ACCUMULATIONS OF A FEW INCHES WILL BE POSSIBLE TONIGHT WITH SOME
ACCUMULATION ON PAVED SURFACES.

FOR DTW...CONFIDENCE IS HIGH IN A BURST OF MODERATE TO HEAVY
SNOWFALL TONIGHT. THE OVERALL POTENTIAL FOR ACCUMULATION ON PAVED
SURFACES REMAINS UNKNOWN.

//DTW THRESHOLD THREATS...

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET TONIGHT.

* MEDIUM CONFIDENCE PRECIPITATION TYPE WILL BE SNOW TONIGHT.

&&

.PREV DISCUSSION...ISSUED 1223 PM EDT MON APR 14 2014

UPDATE...

THE ACTIVE WARM SECTOR THAT BROUGHT STRONG SOUTHERLY WIND GUSTS
OF 60 MPH THIS MORNING HAS NOW BEEN SQUEEZED EASTWARD OUT OF
SOUTHEASTERN MICHIGAN. THE 14.12Z KDTX SOUNDING SHOWED THE
FAVORABLE ENVIRONMENT FOR WIND WELL WITH A MIXED ATMOSPHERE FROM
THE SURFACE TO 7 KFT AGL. THE MAIN COLD FRONT/WIND SHIFT IS NOW
BISECTING THE CWA IN HALF WHICH WILL USHER IN A MORE STABLE
AIRMASS AT THE SURFACE FOR THE AFTERNOON. RECENT OBSERVATIONS
SUPPORT AN INITIAL TEMPERATURE FALL OF ROUGHLY 15 DEGREES...WITH
TEMPERATURES ACROSS WESTERN LOWER MICHIGAN ALREADY IN THE LOW 40S.
BEFORE THE COLDER AND MORE DENSE AIR MASS MAKES IT HERE...LOOKING
AT A FEW HOUR PERIOD WHERE WESTERLY WIND GUSTS OF 30 TO 35 MPH
WILL STILL BE POSSIBLE. GIVEN THE DOWNWARD TREND...CANCELLED THE
HIGH WIND WARNING THAT WAS IN EFFECT.

THE MIDLEVEL DRY SLOT ASSOCIATED WITH THE STRONG LOW PRESSURE
SYSTEM HAS CAUGHT UP TO SOUTHEASTERN MICHIGAN. ISENTROPIC
DOWNGLIDE AND SUBSIDENCE HAS ENDED THE THREAT FOR ADDITIONAL
WIDESPREAD RAINFALL. FOR THIS REASON...ENDED THE FLOOD WATCH.
QUIET WEATHER IN THE PRECIPITATION DEPARTMENT IS NOW EXPECTED
THROUGH APPROXIMATELY 3Z TONIGHT WHEN THE NEXT WAVE WILL BEGIN TO WORK
INTO SOUTHEASTERN MICHIGAN FROM THE SOUTH.

PREV DISCUSSION...ISSUED 415 AM EDT MON APR 14 2014

SHORT TERM... TODAY AND TONIGHT

A PROTOTYPICAL STRONG SPRING LOW PRESSURE SYSTEM WILL BRING A WIDE
RANGE OF IMPACTFUL WEATHER TO SE MICHIGAN TODAY THROUGH TONIGHT. IN
SUMMARY...THE FLOOD WATCH WILL REMAIN IN EFFECT TODAY FOR THE
SAGINAW VALLEY AND NORTHERN THUMB. GUSTY SOUTHERLY WIND WILL BE
MONITORED BUT IS EXPECTED TO REMAIN JUST BELOW ADVISORY LEVELS IN
THE WARM SECTOR OVER SE MICHIGAN WITH A BRIEF 45 MPH GUST POSSIBLE
WITH THE COLD FRONT. RAIN CHANGING TO SNOW TONIGHT IS EXPECTED TO
OCCUR WITH SUFFICIENT RATE FOR A COUPLE INCHES OF ACCUMULATION ON
GRASSY SURFACES MOST LOCATIONS BY SUNRISE TUESDAY.

OBSERVATIONS AT PRESS TIME INDICATE IMPRESSIVE EARLY MORNING
TEMPERATURES AROUND 70 OVER MOST OF THE AREA THAT HAS NOT HAD
RAINFALL DURING THE NIGHT. THESE READINGS WILL BE THE HIGHS FOR THE
DAY WITH TEMPERATURES FALLING OFF A FEW DEGREES AS RAIN OVERSPREADS
THE REST OF THE REGION...AND OF COURSE MORE SHARPLY WITH THE PASSAGE
OF THE FRONT DURING THE AFTERNOON.

SHOWERS WITH A RUMBLE OF THUNDER WILL CONTINUE OVER THE SAGINAW
VALLEY AND NORTHERN THUMB DURING THE MORNING...AND FILL IN OVER THE
REST OF SE MICHIGAN WITHIN THE LOW LEVEL THETA-E RIDGE WITH THE HELP
OF INCREASING SHORT WAVE SUPPORT ALOFT. THIS PROCESS WILL HELP SHIFT
THE PRIMARY RAINFALL AXIS SOUTHWARD FROM THE WATCH AREA DURING THE
MORNING WITH IMPROVING CONDITIONS THERE WITH THE FRONTAL PASSAGE.
AVERAGE RAINFALL TOTALS AROUND 0.5 INCH SOUTH OF THE WATCH AREA
COULD CONTAIN A LOCAL 1 INCH TOTAL WHEN INCLUDING A SURGE OF
CONVECTION ALONG THE FRONT.

IMPRESSIVE COLD ADVECTION WILL THEN GET UNDERWAY DURING THE
AFTERNOON AND CONTINUE TONIGHT. THIS WILL SET UP THE LOW LEVEL
THERMAL PROFILE FOR A RAIN/SNOW TRANSITION. FORCING FOR STRONG
VERTICAL MOTION WILL RELOAD WITH A COMBINATION OF SUPPORT WITH THE
PRIMARY UPPER LEVEL TROUGH AND STRONG MID LEVEL FRONTOGENESIS. THIS
IS EXPECTED TO PRODUCE SNOWFALL RATES CAPABLE OF ACCUMULATING 1 TO
LOCALLY 3 INCHES ON GRASSY SURFACES BY SUNRISE TUESDAY. THE WILD
CARD WILL BE ON PAVED SURFACES WHICH WILL TEND TO HOLD ON TO THE
RECENT WARMTH FOR A LONGER PERIOD OF TIME.

LONG TERM...

LONGWAVE NORTH AMERICAN TROUGH AXIS WILL BE IN PLACE ON TUESDAY OVER
THE CENTRAL GREAT LAKES...RESULTING IN THE COLDEST DAY OF THE
FORECAST PERIOD...AS LOW LEVEL THERMAL TROUGH...850 MB TEMPS OF -12
TO -14 C RESIDE OVER SOUTHEAST MICHIGAN...LIKELY CAPPING MAXES BELOW
40 DEGREES...OR NEAR RECORD TERRITORY FOR APRIL 15TH. STEEP LOW
LEVEL LAPSE RATES INTERSECTING DENDRITIC SNOW GROWTH ZONE WILL
PROBABLY PRODUCE A FEW FLURRIES OR LIGHT SNOW SHOWERS.

AN UPPER WAVE WILL EJECT OUT OF THE GULF OF ALASKA AND ROTATE
THROUGH THE NORTHERN ROCKIES TUESDAY/TUESDAY NIGHT...WITH SURFACE
LOW DEVELOPING OVER NORTHERN PLAINS. THE STRENGTH OF THIS SYSTEM AND
CORRESPONDING WARM ADVECTION PATTERN EXTENDING INTO OUR AREA ON
WEDNESDAY IS IN QUESTION...AS MORE POTENT UPPER WAVE
RETROGRADES/DROPS SOUTHWEST THROUGH CENTRAL CANADA...SHEARING OUT
AND DAMPENING THE LEAD WAVE...ALLOWING THE SURFACE LOW TO QUICKLY
WEAKEN. STILL...INCREASING AND DEEPENING SOUTHWEST FLOW AS WE HEAD
INTO THURSDAY...COUPLED WITH APRIL INSOLATION SHOULD SPELL TEMPS
CLIMBING BACK INTO THE MID/UPPER 50S AT THE VERY LEAST.

00Z EURO INDICATING YET ANOTHER UPPER WAVE COMING OUT OF THE FOUR
CORNERS REGION...ARRIVING FRIDAY NIGHT...PRODUCING ADDITIONAL
RAINFALL TO THE AREA.

MARINE...

A STRONG COLD WILL SWING THROUGH THE CENTRAL GREAT LAKES
TODAY...CAUSING THE SOUTHERLY WINDS OF 20 TO 30 KNOTS TO SHIFT TO
THE NORTHWEST AS WE HEAD INTO TUESDAY. A GOOD DEAL OF COLD AIR WILL
FUNNEL INTO THE AREA TONIGHT INTO TOMORROW...CONDUCIVE TO GOOD WAVE
GROWTH AS LOW LEVEL LAPSE RATES BECOME STEEP...AND WAVES IN EXCESS
OF 4 FEET ARE EXPECTED OVER PARTS OF LAKE HURON. FREQUENT GUSTS OF
25 KNOTS OVER ALL MARINE AREAS ALSO SUPPORTS SMALL CRAFT ADVISORIES
FOR MUCH OF THE NEARSHORE WATERS. HIGH PRESSURE ARRIVING TUESDAY
EVENING WILL ALLOW WINDS TO QUICKLY DIMINISH...REMAINING LIGHT INTO
WEDNESDAY.

HYDROLOGY...

SURFACE OBSERVATIONS AND RADAR ESTIMATES DURING THE NIGHT
INDICATE RAINFALL UNFOLDED ABOUT AS EXPECTED. BASIN AVERAGE TOTALS
RANGE FROM 0.25 INCH TO 0.75 INCH ACROSS THE
CASS...TITTABAWASSEE...AND SAGINAW BASINS SINCE 00Z LAST NIGHT.
THE BULK FELL 00Z-06Z BUT WITH THE CASS ADDING TO TOTALS SINCE
THEN UP TO PRESS TIME AND POSSIBLY PUSHING AN INCH FOR A 12 HR
TOTAL 00Z-12Z THIS MORNING. GAGE OBSERVATIONS ARE ON A SLIGHTLY
STEEPER GLIDE PATH WITH THE LATEST FORECASTS AND ON TRACK FOR OF A
HIGH CONFIDENCE MODERATE STAGE ON THE TITTABAWASSEE...AND
CHALLENGE FOR MAJOR STAGE. OVERNIGHT RAINFALL DISTRIBUTION SHOULD
ALSO KEEP THE CASS RIVER ON PACE TO MATCH THE FORECAST UPDATED
LAST EVENING FOR FLOOD STAGE AT FRANKENMUTH DURING THE MORNING.
DOWNSTREAM ON THE SAGINAW...THERE IS MORE TIME TO ASSESS THE TOTAL
BASIN COLLECTION IN UPCOMING FORECASTS.

CLIMATE...

SNOWIEST WINTER SEASON

CITY       2013-2014        RECORD
FLINT       82.6"      82.9" (1974-75)
DETROIT     91.7"      93.6" (1880-81)

LOW MAX RECORDS FOR APRIL 15:

DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

&&

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

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL 4 PM TUESDAY.

LAKE ST CLAIR...
     SMALL CRAFT ADVISORY...UNTIL 4 PM MONDAY.

MI WATERS OF LAKE ERIE...
     SMALL CRAFT ADVISORY...UNTIL 4 PM MONDAY.

&&

$$

AVIATION.....CB
UPDATE.......CB
SHORT TERM...BT
LONG TERM....SF
MARINE.......SF
HYDROLOGY....BT
CLIMATE......SF


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











000
FXUS63 KDTX 141753
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
153 PM EDT MON APR 14 2014


.AVIATION...

//DISCUSSION...

THE MAIN SURFACE COLD FRONT HAS PASSED THROUGH SOUTHEASTERN
MICHIGAN. COLDER AND MORE STABLE AIR WILL NOW FILTER INTO THE
REGION ALLOWING WIND SPEEDS TO MARGINALLY EASE DURING THE NEXT
HOUR OR TWO IN THE 20 TO 30 MPH RANGE. THE NEXT WAVE OF LOW
PRESSURE WILL LIFT DUE NORTHWARD THIS EVENING. PRECIPITATION IS
EXPECTED TO OVERSPREAD SOUTHEASTER MICHIGAN AFTER 3Z...PERSISTING
UNTIL AROUND 10Z. IT IS APPEARING MORE LIKELY THAT HIGH
PRECIPITATION INTENSITY WILL BE PRESENT DUE TO LOW STATIC
STABILITY ALOFT. THESE HIGHER PRECIPITATION RATES WILL SUPPORT A
PRECIPITATION TYPE AS ALL SNOW AT THE START. SNOWFALL
ACCUMULATIONS OF A FEW INCHES WILL BE POSSIBLE TONIGHT WITH SOME
ACCUMULATION ON PAVED SURFACES.

FOR DTW...CONFIDENCE IS HIGH IN A BURST OF MODERATE TO HEAVY
SNOWFALL TONIGHT. THE OVERALL POTENTIAL FOR ACCUMULATION ON PAVED
SURFACES REMAINS UNKNOWN.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE IN WIND GUSTS GREATER THAN 35 KNOTS THIS
  MORNING.

* MEDIUM CONFIDENCE IN THUNDERSTORMS THIS MORNING AND EARLY
AFTERNOON.

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET THIS AFTERNOON AND
TONIGHT.

* MEDIUM CONFIDENCE THAT PRECIPITATION TYPE WILL CHANGE TO SNOW
TONIGHT.

&&

.PREV DISCUSSION...ISSUED 1223 PM EDT MON APR 14 2014

UPDATE...

THE ACTIVE WARM SECTOR THAT BROUGHT STRONG SOUTHERLY WIND GUSTS
OF 60 MPH THIS MORNING HAS NOW BEEN SQUEEZED EASTWARD OUT OF
SOUTHEASTERN MICHIGAN. THE 14.12Z KDTX SOUNDING SHOWED THE
FAVORABLE ENVIRONMENT FOR WIND WELL WITH A MIXED ATMOSPHERE FROM
THE SURFACE TO 7 KFT AGL. THE MAIN COLD FRONT/WIND SHIFT IS NOW
BISECTING THE CWA IN HALF WHICH WILL USHER IN A MORE STABLE
AIRMASS AT THE SURFACE FOR THE AFTERNOON. RECENT OBSERVATIONS
SUPPORT AN INITIAL TEMPERATURE FALL OF ROUGHLY 15 DEGREES...WITH
TEMPERATURES ACROSS WESTERN LOWER MICHIGAN ALREADY IN THE LOW 40S.
BEFORE THE COLDER AND MORE DENSE AIR MASS MAKES IT HERE...LOOKING
AT A FEW HOUR PERIOD WHERE WESTERLY WIND GUSTS OF 30 TO 35 MPH
WILL STILL BE POSSIBLE. GIVEN THE DOWNWARD TREND...CANCELLED THE
HIGH WIND WARNING THAT WAS IN EFFECT.

THE MIDLEVEL DRY SLOT ASSOCIATED WITH THE STRONG LOW PRESSURE
SYSTEM HAS CAUGHT UP TO SOUTHEASTERN MICHIGAN. ISENTROPIC
DOWNGLIDE AND SUBSIDENCE HAS ENDED THE THREAT FOR ADDITIONAL
WIDESPREAD RAINFALL. FOR THIS REASON...ENDED THE FLOOD WATCH.
QUIET WEATHER IN THE PRECIPITATION DEPARTMENT IS NOW EXPECTED
THROUGH APPROXIMATELY 3Z TONIGHT WHEN THE NEXT WAVE WILL BEGIN TO WORK
INTO SOUTHEASTERN MICHIGAN FROM THE SOUTH.

PREV DISCUSSION...ISSUED 415 AM EDT MON APR 14 2014

SHORT TERM... TODAY AND TONIGHT

A PROTOTYPICAL STRONG SPRING LOW PRESSURE SYSTEM WILL BRING A WIDE
RANGE OF IMPACTFUL WEATHER TO SE MICHIGAN TODAY THROUGH TONIGHT. IN
SUMMARY...THE FLOOD WATCH WILL REMAIN IN EFFECT TODAY FOR THE
SAGINAW VALLEY AND NORTHERN THUMB. GUSTY SOUTHERLY WIND WILL BE
MONITORED BUT IS EXPECTED TO REMAIN JUST BELOW ADVISORY LEVELS IN
THE WARM SECTOR OVER SE MICHIGAN WITH A BRIEF 45 MPH GUST POSSIBLE
WITH THE COLD FRONT. RAIN CHANGING TO SNOW TONIGHT IS EXPECTED TO
OCCUR WITH SUFFICIENT RATE FOR A COUPLE INCHES OF ACCUMULATION ON
GRASSY SURFACES MOST LOCATIONS BY SUNRISE TUESDAY.

OBSERVATIONS AT PRESS TIME INDICATE IMPRESSIVE EARLY MORNING
TEMPERATURES AROUND 70 OVER MOST OF THE AREA THAT HAS NOT HAD
RAINFALL DURING THE NIGHT. THESE READINGS WILL BE THE HIGHS FOR THE
DAY WITH TEMPERATURES FALLING OFF A FEW DEGREES AS RAIN OVERSPREADS
THE REST OF THE REGION...AND OF COURSE MORE SHARPLY WITH THE PASSAGE
OF THE FRONT DURING THE AFTERNOON.

SHOWERS WITH A RUMBLE OF THUNDER WILL CONTINUE OVER THE SAGINAW
VALLEY AND NORTHERN THUMB DURING THE MORNING...AND FILL IN OVER THE
REST OF SE MICHIGAN WITHIN THE LOW LEVEL THETA-E RIDGE WITH THE HELP
OF INCREASING SHORT WAVE SUPPORT ALOFT. THIS PROCESS WILL HELP SHIFT
THE PRIMARY RAINFALL AXIS SOUTHWARD FROM THE WATCH AREA DURING THE
MORNING WITH IMPROVING CONDITIONS THERE WITH THE FRONTAL PASSAGE.
AVERAGE RAINFALL TOTALS AROUND 0.5 INCH SOUTH OF THE WATCH AREA
COULD CONTAIN A LOCAL 1 INCH TOTAL WHEN INCLUDING A SURGE OF
CONVECTION ALONG THE FRONT.

IMPRESSIVE COLD ADVECTION WILL THEN GET UNDERWAY DURING THE
AFTERNOON AND CONTINUE TONIGHT. THIS WILL SET UP THE LOW LEVEL
THERMAL PROFILE FOR A RAIN/SNOW TRANSITION. FORCING FOR STRONG
VERTICAL MOTION WILL RELOAD WITH A COMBINATION OF SUPPORT WITH THE
PRIMARY UPPER LEVEL TROUGH AND STRONG MID LEVEL FRONTOGENESIS. THIS
IS EXPECTED TO PRODUCE SNOWFALL RATES CAPABLE OF ACCUMULATING 1 TO
LOCALLY 3 INCHES ON GRASSY SURFACES BY SUNRISE TUESDAY. THE WILD
CARD WILL BE ON PAVED SURFACES WHICH WILL TEND TO HOLD ON TO THE
RECENT WARMTH FOR A LONGER PERIOD OF TIME.

LONG TERM...

LONGWAVE NORTH AMERICAN TROUGH AXIS WILL BE IN PLACE ON TUESDAY OVER
THE CENTRAL GREAT LAKES...RESULTING IN THE COLDEST DAY OF THE
FORECAST PERIOD...AS LOW LEVEL THERMAL TROUGH...850 MB TEMPS OF -12
TO -14 C RESIDE OVER SOUTHEAST MICHIGAN...LIKELY CAPPING MAXES BELOW
40 DEGREES...OR NEAR RECORD TERRITORY FOR APRIL 15TH. STEEP LOW
LEVEL LAPSE RATES INTERSECTING DENDRITIC SNOW GROWTH ZONE WILL
PROBABLY PRODUCE A FEW FLURRIES OR LIGHT SNOW SHOWERS.

AN UPPER WAVE WILL EJECT OUT OF THE GULF OF ALASKA AND ROTATE
THROUGH THE NORTHERN ROCKIES TUESDAY/TUESDAY NIGHT...WITH SURFACE
LOW DEVELOPING OVER NORTHERN PLAINS. THE STRENGTH OF THIS SYSTEM AND
CORRESPONDING WARM ADVECTION PATTERN EXTENDING INTO OUR AREA ON
WEDNESDAY IS IN QUESTION...AS MORE POTENT UPPER WAVE
RETROGRADES/DROPS SOUTHWEST THROUGH CENTRAL CANADA...SHEARING OUT
AND DAMPENING THE LEAD WAVE...ALLOWING THE SURFACE LOW TO QUICKLY
WEAKEN. STILL...INCREASING AND DEEPENING SOUTHWEST FLOW AS WE HEAD
INTO THURSDAY...COUPLED WITH APRIL INSOLATION SHOULD SPELL TEMPS
CLIMBING BACK INTO THE MID/UPPER 50S AT THE VERY LEAST.

00Z EURO INDICATING YET ANOTHER UPPER WAVE COMING OUT OF THE FOUR
CORNERS REGION...ARRIVING FRIDAY NIGHT...PRODUCING ADDITIONAL
RAINFALL TO THE AREA.

MARINE...

A STRONG COLD WILL SWING THROUGH THE CENTRAL GREAT LAKES
TODAY...CAUSING THE SOUTHERLY WINDS OF 20 TO 30 KNOTS TO SHIFT TO
THE NORTHWEST AS WE HEAD INTO TUESDAY. A GOOD DEAL OF COLD AIR WILL
FUNNEL INTO THE AREA TONIGHT INTO TOMORROW...CONDUCIVE TO GOOD WAVE
GROWTH AS LOW LEVEL LAPSE RATES BECOME STEEP...AND WAVES IN EXCESS
OF 4 FEET ARE EXPECTED OVER PARTS OF LAKE HURON. FREQUENT GUSTS OF
25 KNOTS OVER ALL MARINE AREAS ALSO SUPPORTS SMALL CRAFT ADVISORIES
FOR MUCH OF THE NEARSHORE WATERS. HIGH PRESSURE ARRIVING TUESDAY
EVENING WILL ALLOW WINDS TO QUICKLY DIMINISH...REMAINING LIGHT INTO
WEDNESDAY.

HYDROLOGY...

SURFACE OBSERVATIONS AND RADAR ESTIMATES DURING THE NIGHT
INDICATE RAINFALL UNFOLDED ABOUT AS EXPECTED. BASIN AVERAGE TOTALS
RANGE FROM 0.25 INCH TO 0.75 INCH ACROSS THE
CASS...TITTABAWASSEE...AND SAGINAW BASINS SINCE 00Z LAST NIGHT.
THE BULK FELL 00Z-06Z BUT WITH THE CASS ADDING TO TOTALS SINCE
THEN UP TO PRESS TIME AND POSSIBLY PUSHING AN INCH FOR A 12 HR
TOTAL 00Z-12Z THIS MORNING. GAGE OBSERVATIONS ARE ON A SLIGHTLY
STEEPER GLIDE PATH WITH THE LATEST FORECASTS AND ON TRACK FOR OF A
HIGH CONFIDENCE MODERATE STAGE ON THE TITTABAWASSEE...AND
CHALLENGE FOR MAJOR STAGE. OVERNIGHT RAINFALL DISTRIBUTION SHOULD
ALSO KEEP THE CASS RIVER ON PACE TO MATCH THE FORECAST UPDATED
LAST EVENING FOR FLOOD STAGE AT FRANKENMUTH DURING THE MORNING.
DOWNSTREAM ON THE SAGINAW...THERE IS MORE TIME TO ASSESS THE TOTAL
BASIN COLLECTION IN UPCOMING FORECASTS.

CLIMATE...

SNOWIEST WINTER SEASON

CITY       2013-2014        RECORD
FLINT       82.6"      82.9" (1974-75)
DETROIT     91.7"      93.6" (1880-81)

LOW MAX RECORDS FOR APRIL 15:

DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

&&

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

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL 4 PM TUESDAY.

LAKE ST CLAIR...
     SMALL CRAFT ADVISORY...UNTIL 4 PM MONDAY.

MI WATERS OF LAKE ERIE...
     SMALL CRAFT ADVISORY...UNTIL 4 PM MONDAY.

&&

$$

AVIATION.....CB
UPDATE.......CB
SHORT TERM...BT
LONG TERM....SF
MARINE.......SF
HYDROLOGY....BT
CLIMATE......SF


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








000
FXUS63 KDTX 141623
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1223 PM EDT MON APR 14 2014

.UPDATE...

THE ACTIVE WARM SECTOR THAT BROUGHT STRONG SOUTHERLY WIND GUSTS
OF 60 MPH THIS MORNING HAS NOW BEEN SQUEEZED EASTWARD OUT OF
SOUTHEASTERN MICHIGAN. THE 14.12Z KDTX SOUNDING SHOWED THE
FAVORABLE ENVIRONMENT FOR WIND WELL WITH A MIXED ATMOSPHERE FROM
THE SURFACE TO 7 KFT AGL. THE MAIN COLD FRONT/WIND SHIFT IS NOW
BISECTING THE CWA IN HALF WHICH WILL USHER IN A MORE STABLE
AIRMASS AT THE SURFACE FOR THE AFTERNOON. RECENT OBSERVATIONS
SUPPORT AN INITIAL TEMPERATURE FALL OF ROUGHLY 15 DEGREES...WITH
TEMPERATURES ACROSS WESTERN LOWER MICHIGAN ALREADY IN THE LOW 40S.
BEFORE THE COLDER AND MORE DENSE AIR MASS MAKES IT HERE...LOOKING
AT A FEW HOUR PERIOD WHERE WESTERLY WIND GUSTS OF 30 TO 35 MPH
WILL STILL BE POSSIBLE. GIVEN THE DOWNWARD TREND...CANCELLED THE
HIGH WIND WARNING THAT WAS IN EFFECT.

THE MIDLEVEL DRY SLOT ASSOCIATED WITH THE STRONG LOW PRESSURE
SYSTEM HAS CAUGHT UP TO SOUTHEASTERN MICHIGAN. ISENTROPIC
DOWNGLIDE AND SUBSIDENCE HAS ENDED THE THREAT FOR ADDITIONAL
WIDESPREAD RAINFALL. FOR THIS REASON...ENDED THE FLOOD WATCH.
QUIET WEATHER IN THE PRECIPITATION DEPARTMENT IS NOW EXPECTED
THROUGH APPROXIMATELY 3Z TONIGHT WHEN THE NEXT WAVE WILL BEGIN TO WORK
INTO SOUTHEASTERN MICHIGAN FROM THE SOUTH.

&&

.AVIATION...ISSUED 710 AM EDT MON APR 14 2014

//DISCUSSION...

VFR CONDITIONS WITH A MILD BUT GUSTY SOUTH WIND WILL BE IN PLACE TO
START THE MORNING AHEAD OF LOW PRESSURE SLIDING TO THE WEST AND
NORTH OF THE TERMINAL CORRIDOR. POCKETS OF SHOWERS WILL BRING BRIEF
MVFR/IFR CONDITIONS AND WIND GUSTS POTENTIALLY REACHING 40 KNOTS
PRECEDING THE FRONT. CONDITIONS WILL THEN WORSEN TO LOWER END MVFR
CEILING OVER LARGER AREAS AS THE LOW EXITS AND PULLS A STRONG COLD
FRONT THROUGH SE MICHIGAN. SHORT LIVED IMPROVEMENT TO VFR IS AGAIN
EXPECTED BY MID AFTERNOON BEFORE A NEW ROUND OF WINTER WEATHER MOVES
IN TONIGHT. A MIX OF RAIN AND SNOW WITH LOW CEILING WILL PERSIST
THROUGH SUNRISE TUESDAY ALONG WITH A BRISK NORTHWEST WIND.

FOR DTW... A PREFRONTAL TROUGH WILL BRING A BAND OF SHOWERS CAPABLE
OF BRIEF HEAVY RAINFALL AND 40 KNOT WIND GUSTS. IT MAY BE TOO SOON
IN THE DAY FOR THUNDERSTORM DEVELOPMENT BUT THESE TRENDS WILL BE
MONITORED. THE COLD FRONT PASSAGE BY 17Z WILL PULL COLD AIR BACK
INTO THE REGION DURING THE REST OF TODAY AND TONIGHT. THIS WILL
CHANGE PRECIPITATION TYPE TO SNOW BY MIDNIGHT WITH CONFIDENCE
INCREASING ON POTENTIAL FOR AN INCH OR TWO OF SNOW ACCUMULATION ON
GRASSY SURFACES BY SUNRISE TUESDAY. CONFIDENCE IS LOWER ON PAVED
SURFACES DUE TO HEAT RETENTION FROM RECENT WARM DAYS.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE IN WIND GUSTS GREATER THAN 35 KNOTS THIS
  MORNING.

* MEDIUM CONFIDENCE IN THUNDERSTORMS THIS MORNING AND EARLY
AFTERNOON.

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET THIS AFTERNOON AND
TONIGHT.

* MEDIUM CONFIDENCE THAT PRECIPITATION TYPE WILL CHANGE TO SNOW
TONIGHT.

&&

.PREV DISCUSSION...ISSUED 415 AM EDT MON APR 14 2014

SHORT TERM... TODAY AND TONIGHT

A PROTOTYPICAL STRONG SPRING LOW PRESSURE SYSTEM WILL BRING A WIDE
RANGE OF IMPACTFUL WEATHER TO SE MICHIGAN TODAY THROUGH TONIGHT. IN
SUMMARY...THE FLOOD WATCH WILL REMAIN IN EFFECT TODAY FOR THE
SAGINAW VALLEY AND NORTHERN THUMB. GUSTY SOUTHERLY WIND WILL BE
MONITORED BUT IS EXPECTED TO REMAIN JUST BELOW ADVISORY LEVELS IN
THE WARM SECTOR OVER SE MICHIGAN WITH A BRIEF 45 MPH GUST POSSIBLE
WITH THE COLD FRONT. RAIN CHANGING TO SNOW TONIGHT IS EXPECTED TO
OCCUR WITH SUFFICIENT RATE FOR A COUPLE INCHES OF ACCUMULATION ON
GRASSY SURFACES MOST LOCATIONS BY SUNRISE TUESDAY.

OBSERVATIONS AT PRESS TIME INDICATE IMPRESSIVE EARLY MORNING
TEMPERATURES AROUND 70 OVER MOST OF THE AREA THAT HAS NOT HAD
RAINFALL DURING THE NIGHT. THESE READINGS WILL BE THE HIGHS FOR THE
DAY WITH TEMPERATURES FALLING OFF A FEW DEGREES AS RAIN OVERSPREADS
THE REST OF THE REGION...AND OF COURSE MORE SHARPLY WITH THE PASSAGE
OF THE FRONT DURING THE AFTERNOON.

SHOWERS WITH A RUMBLE OF THUNDER WILL CONTINUE OVER THE SAGINAW
VALLEY AND NORTHERN THUMB DURING THE MORNING...AND FILL IN OVER THE
REST OF SE MICHIGAN WITHIN THE LOW LEVEL THETA-E RIDGE WITH THE HELP
OF INCREASING SHORT WAVE SUPPORT ALOFT. THIS PROCESS WILL HELP SHIFT
THE PRIMARY RAINFALL AXIS SOUTHWARD FROM THE WATCH AREA DURING THE
MORNING WITH IMPROVING CONDITIONS THERE WITH THE FRONTAL PASSAGE.
AVERAGE RAINFALL TOTALS AROUND 0.5 INCH SOUTH OF THE WATCH AREA
COULD CONTAIN A LOCAL 1 INCH TOTAL WHEN INCLUDING A SURGE OF
CONVECTION ALONG THE FRONT.

IMPRESSIVE COLD ADVECTION WILL THEN GET UNDERWAY DURING THE
AFTERNOON AND CONTINUE TONIGHT. THIS WILL SET UP THE LOW LEVEL
THERMAL PROFILE FOR A RAIN/SNOW TRANSITION. FORCING FOR STRONG
VERTICAL MOTION WILL RELOAD WITH A COMBINATION OF SUPPORT WITH THE
PRIMARY UPPER LEVEL TROUGH AND STRONG MID LEVEL FRONTOGENESIS. THIS
IS EXPECTED TO PRODUCE SNOWFALL RATES CAPABLE OF ACCUMULATING 1 TO
LOCALLY 3 INCHES ON GRASSY SURFACES BY SUNRISE TUESDAY. THE WILD
CARD WILL BE ON PAVED SURFACES WHICH WILL TEND TO HOLD ON TO THE
RECENT WARMTH FOR A LONGER PERIOD OF TIME.

LONG TERM...

LONGWAVE NORTH AMERICAN TROUGH AXIS WILL BE IN PLACE ON TUESDAY OVER
THE CENTRAL GREAT LAKES...RESULTING IN THE COLDEST DAY OF THE
FORECAST PERIOD...AS LOW LEVEL THERMAL TROUGH...850 MB TEMPS OF -12
TO -14 C RESIDE OVER SOUTHEAST MICHIGAN...LIKELY CAPPING MAXES BELOW
40 DEGREES...OR NEAR RECORD TERRITORY FOR APRIL 15TH. STEEP LOW
LEVEL LAPSE RATES INTERSECTING DENDRITIC SNOW GROWTH ZONE WILL
PROBABLY PRODUCE A FEW FLURRIES OR LIGHT SNOW SHOWERS.

AN UPPER WAVE WILL EJECT OUT OF THE GULF OF ALASKA AND ROTATE
THROUGH THE NORTHERN ROCKIES TUESDAY/TUESDAY NIGHT...WITH SURFACE
LOW DEVELOPING OVER NORTHERN PLAINS. THE STRENGTH OF THIS SYSTEM AND
CORRESPONDING WARM ADVECTION PATTERN EXTENDING INTO OUR AREA ON
WEDNESDAY IS IN QUESTION...AS MORE POTENT UPPER WAVE
RETROGRADES/DROPS SOUTHWEST THROUGH CENTRAL CANADA...SHEARING OUT
AND DAMPENING THE LEAD WAVE...ALLOWING THE SURFACE LOW TO QUICKLY
WEAKEN. STILL...INCREASING AND DEEPENING SOUTHWEST FLOW AS WE HEAD
INTO THURSDAY...COUPLED WITH APRIL INSOLATION SHOULD SPELL TEMPS
CLIMBING BACK INTO THE MID/UPPER 50S AT THE VERY LEAST.

00Z EURO INDICATING YET ANOTHER UPPER WAVE COMING OUT OF THE FOUR
CORNERS REGION...ARRIVING FRIDAY NIGHT...PRODUCING ADDITIONAL
RAINFALL TO THE AREA.

MARINE...

A STRONG COLD WILL SWING THROUGH THE CENTRAL GREAT LAKES
TODAY...CAUSING THE SOUTHERLY WINDS OF 20 TO 30 KNOTS TO SHIFT TO
THE NORTHWEST AS WE HEAD INTO TUESDAY. A GOOD DEAL OF COLD AIR WILL
FUNNEL INTO THE AREA TONIGHT INTO TOMORROW...CONDUCIVE TO GOOD WAVE
GROWTH AS LOW LEVEL LAPSE RATES BECOME STEEP...AND WAVES IN EXCESS
OF 4 FEET ARE EXPECTED OVER PARTS OF LAKE HURON. FREQUENT GUSTS OF
25 KNOTS OVER ALL MARINE AREAS ALSO SUPPORTS SMALL CRAFT ADVISORIES
FOR MUCH OF THE NEARSHORE WATERS. HIGH PRESSURE ARRIVING TUESDAY
EVENING WILL ALLOW WINDS TO QUICKLY DIMINISH...REMAINING LIGHT INTO
WEDNESDAY.

HYDROLOGY...

SURFACE OBSERVATIONS AND RADAR ESTIMATES DURING THE NIGHT
INDICATE RAINFALL UNFOLDED ABOUT AS EXPECTED. BASIN AVERAGE TOTALS
RANGE FROM 0.25 INCH TO 0.75 INCH ACROSS THE
CASS...TITTABAWASSEE...AND SAGINAW BASINS SINCE 00Z LAST NIGHT.
THE BULK FELL 00Z-06Z BUT WITH THE CASS ADDING TO TOTALS SINCE
THEN UP TO PRESS TIME AND POSSIBLY PUSHING AN INCH FOR A 12 HR
TOTAL 00Z-12Z THIS MORNING. GAGE OBSERVATIONS ARE ON A SLIGHTLY
STEEPER GLIDE PATH WITH THE LATEST FORECASTS AND ON TRACK FOR OF A
HIGH CONFIDENCE MODERATE STAGE ON THE TITTABAWASSEE...AND
CHALLENGE FOR MAJOR STAGE. OVERNIGHT RAINFALL DISTRIBUTION SHOULD
ALSO KEEP THE CASS RIVER ON PACE TO MATCH THE FORECAST UPDATED
LAST EVENING FOR FLOOD STAGE AT FRANKENMUTH DURING THE MORNING.
DOWNSTREAM ON THE SAGINAW...THERE IS MORE TIME TO ASSESS THE TOTAL
BASIN COLLECTION IN UPCOMING FORECASTS.

CLIMATE...

SNOWIEST WINTER SEASON

CITY       2013-2014        RECORD
FLINT       82.6"      82.9" (1974-75)
DETROIT     91.7"      93.6" (1880-81)

LOW MAX RECORDS FOR APRIL 15:

DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

&&

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

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL 4 PM TUESDAY.

LAKE ST CLAIR...
     SMALL CRAFT ADVISORY...UNTIL 4 PM MONDAY.

MI WATERS OF LAKE ERIE...
     SMALL CRAFT ADVISORY...UNTIL 4 PM MONDAY.

&&

$$

UPDATE.......CB
AVIATION.....BT
SHORT TERM...BT
LONG TERM....SF
MARINE.......SF
HYDROLOGY....BT
CLIMATE......SF
HYDROLOGY....CB
CLIMATE......CB


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








000
FXUS63 KDTX 141110
AFDDTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
710 AM EDT MON APR 14 2014

.AVIATION...

//DISCUSSION...

VFR CONDITIONS WITH A MILD BUT GUSTY SOUTH WIND WILL BE IN PLACE TO
START THE MORNING AHEAD OF LOW PRESSURE SLIDING TO THE WEST AND
NORTH OF THE TERMINAL CORRIDOR. POCKETS OF SHOWERS WILL BRING BRIEF
MVFR/IFR CONDITIONS AND WIND GUSTS POTENTIALLY REACHING 40 KNOTS
PRECEDING THE FRONT. CONDITIONS WILL THEN WORSEN TO LOWER END MVFR
CEILING OVER LARGER AREAS AS THE LOW EXITS AND PULLS A STRONG COLD
FRONT THROUGH SE MICHIGAN. SHORT LIVED IMPROVEMENT TO VFR IS AGAIN
EXPECTED BY MID AFTERNOON BEFORE A NEW ROUND OF WINTER WEATHER MOVES
IN TONIGHT. A MIX OF RAIN AND SNOW WITH LOW CEILING WILL PERSIST
THROUGH SUNRISE TUESDAY ALONG WITH A BRISK NORTHWEST WIND.

FOR DTW... A PREFRONTAL TROUGH WILL BRING A BAND OF SHOWERS CAPABLE
OF BRIEF HEAVY RAINFALL AND 40 KNOT WIND GUSTS. IT MAY BE TOO SOON
IN THE DAY FOR THUNDERSTORM DEVELOPMENT BUT THESE TRENDS WILL BE
MONITORED. THE COLD FRONT PASSAGE BY 17Z WILL PULL COLD AIR BACK
INTO THE REGION DURING THE REST OF TODAY AND TONIGHT. THIS WILL
CHANGE PRECIPITATION TYPE TO SNOW BY MIDNIGHT WITH CONFIDENCE
INCREASING ON POTENTIAL FOR AN INCH OR TWO OF SNOW ACCUMULATION ON
GRASSY SURFACES BY SUNRISE TUESDAY. CONFIDENCE IS LOWER ON PAVED
SURFACES DUE TO HEAT RETENTION FROM RECENT WARM DAYS.

//DTW THRESHOLD THREATS...

* MEDIUM CONFIDENCE IN WIND GUSTS GREATER THAN 35 KNOTS THIS
  MORNING.

* MEDIUM CONFIDENCE IN THUNDERSTORMS THIS MORNING AND EARLY
AFTERNOON.

* HIGH CONFIDENCE IN CIGS BELOW 5000 FEET THIS AFTERNOON AND
TONIGHT.

* MEDIUM CONFIDENCE THAT PRECIPITATION TYPE WILL CHANGE TO SNOW
TONIGHT.

&&

.PREV DISCUSSION...ISSUED 415 AM EDT MON APR 14 2014

SHORT TERM... TODAY AND TONIGHT

A PROTOTYPICAL STRONG SPRING LOW PRESSURE SYSTEM WILL BRING A WIDE
RANGE OF IMPACTFUL WEATHER TO SE MICHIGAN TODAY THROUGH TONIGHT. IN
SUMMARY...THE FLOOD WATCH WILL REMAIN IN EFFECT TODAY FOR THE
SAGINAW VALLEY AND NORTHERN THUMB. GUSTY SOUTHERLY WIND WILL BE
MONITORED BUT IS EXPECTED TO REMAIN JUST BELOW ADVISORY LEVELS IN
THE WARM SECTOR OVER SE MICHIGAN WITH A BRIEF 45 MPH GUST POSSIBLE
WITH THE COLD FRONT. RAIN CHANGING TO SNOW TONIGHT IS EXPECTED TO
OCCUR WITH SUFFICIENT RATE FOR A COUPLE INCHES OF ACCUMULATION ON
GRASSY SURFACES MOST LOCATIONS BY SUNRISE TUESDAY.

OBSERVATIONS AT PRESS TIME INDICATE IMPRESSIVE EARLY MORNING
TEMPERATURES AROUND 70 OVER MOST OF THE AREA THAT HAS NOT HAD
RAINFALL DURING THE NIGHT. THESE READINGS WILL BE THE HIGHS FOR THE
DAY WITH TEMPERATURES FALLING OFF A FEW DEGREES AS RAIN OVERSPREADS
THE REST OF THE REGION...AND OF COURSE MORE SHARPLY WITH THE PASSAGE
OF THE FRONT DURING THE AFTERNOON.

SHOWERS WITH A RUMBLE OF THUNDER WILL CONTINUE OVER THE SAGINAW
VALLEY AND NORTHERN THUMB DURING THE MORNING...AND FILL IN OVER THE
REST OF SE MICHIGAN WITHIN THE LOW LEVEL THETA-E RIDGE WITH THE HELP
OF INCREASING SHORT WAVE SUPPORT ALOFT. THIS PROCESS WILL HELP SHIFT
THE PRIMARY RAINFALL AXIS SOUTHWARD FROM THE WATCH AREA DURING THE
MORNING WITH IMPROVING CONDITIONS THERE WITH THE FRONTAL PASSAGE.
AVERAGE RAINFALL TOTALS AROUND 0.5 INCH SOUTH OF THE WATCH AREA
COULD CONTAIN A LOCAL 1 INCH TOTAL WHEN INCLUDING A SURGE OF
CONVECTION ALONG THE FRONT.

IMPRESSIVE COLD ADVECTION WILL THEN GET UNDERWAY DURING THE
AFTERNOON AND CONTINUE TONIGHT. THIS WILL SET UP THE LOW LEVEL
THERMAL PROFILE FOR A RAIN/SNOW TRANSITION. FORCING FOR STRONG
VERTICAL MOTION WILL RELOAD WITH A COMBINATION OF SUPPORT WITH THE
PRIMARY UPPER LEVEL TROUGH AND STRONG MID LEVEL FRONTOGENESIS. THIS
IS EXPECTED TO PRODUCE SNOWFALL RATES CAPABLE OF ACCUMULATING 1 TO
LOCALLY 3 INCHES ON GRASSY SURFACES BY SUNRISE TUESDAY. THE WILD
CARD WILL BE ON PAVED SURFACES WHICH WILL TEND TO HOLD ON TO THE
RECENT WARMTH FOR A LONGER PERIOD OF TIME.

LONG TERM...

LONGWAVE NORTH AMERICAN TROUGH AXIS WILL BE IN PLACE ON TUESDAY OVER
THE CENTRAL GREAT LAKES...RESULTING IN THE COLDEST DAY OF THE
FORECAST PERIOD...AS LOW LEVEL THERMAL TROUGH...850 MB TEMPS OF -12
TO -14 C RESIDE OVER SOUTHEAST MICHIGAN...LIKELY CAPPING MAXES BELOW
40 DEGREES...OR NEAR RECORD TERRITORY FOR APRIL 15TH. STEEP LOW
LEVEL LAPSE RATES INTERSECTING DENDRITIC SNOW GROWTH ZONE WILL
PROBABLY PRODUCE A FEW FLURRIES OR LIGHT SNOW SHOWERS.

AN UPPER WAVE WILL EJECT OUT OF THE GULF OF ALASKA AND ROTATE
THROUGH THE NORTHERN ROCKIES TUESDAY/TUESDAY NIGHT...WITH SURFACE
LOW DEVELOPING OVER NORTHERN PLAINS. THE STRENGTH OF THIS SYSTEM AND
CORRESPONDING WARM ADVECTION PATTERN EXTENDING INTO OUR AREA ON
WEDNESDAY IS IN QUESTION...AS MORE POTENT UPPER WAVE
RETROGRADES/DROPS SOUTHWEST THROUGH CENTRAL CANADA...SHEARING OUT
AND DAMPENING THE LEAD WAVE...ALLOWING THE SURFACE LOW TO QUICKLY
WEAKEN. STILL...INCREASING AND DEEPENING SOUTHWEST FLOW AS WE HEAD
INTO THURSDAY...COUPLED WITH APRIL INSOLATION SHOULD SPELL TEMPS
CLIMBING BACK INTO THE MID/UPPER 50S AT THE VERY LEAST.

00Z EURO INDICATING YET ANOTHER UPPER WAVE COMING OUT OF THE FOUR
CORNERS REGION...ARRIVING FRIDAY NIGHT...PRODUCING ADDITIONAL
RAINFALL TO THE AREA.

MARINE...

A STRONG COLD WILL SWING THROUGH THE CENTRAL GREAT LAKES
TODAY...CAUSING THE SOUTHERLY WINDS OF 20 TO 30 KNOTS TO SHIFT TO
THE NORTHWEST AS WE HEAD INTO TUESDAY. A GOOD DEAL OF COLD AIR WILL
FUNNEL INTO THE AREA TONIGHT INTO TOMORROW...CONDUCIVE TO GOOD WAVE
GROWTH AS LOW LEVEL LAPSE RATES BECOME STEEP...AND WAVES IN EXCESS
OF 4 FEET ARE EXPECTED OVER PARTS OF LAKE HURON. FREQUENT GUSTS OF
25 KNOTS OVER ALL MARINE AREAS ALSO SUPPORTS SMALL CRAFT ADVISORIES
FOR MUCH OF THE NEARSHORE WATERS. HIGH PRESSURE ARRIVING TUESDAY
EVENING WILL ALLOW WINDS TO QUICKLY DIMINISH...REMAINING LIGHT INTO
WEDNESDAY.

HYDROLOGY...

SURFACE OBSERVATIONS AND RADAR ESTIMATES DURING THE NIGHT
INDICATE RAINFALL UNFOLDED ABOUT AS EXPECTED. BASIN AVERAGE TOTALS
RANGE FROM 0.25 INCH TO 0.75 INCH ACROSS THE
CASS...TITTABAWASSEE...AND SAGINAW BASINS SINCE 00Z LAST NIGHT.
THE BULK FELL 00Z-06Z BUT WITH THE CASS ADDING TO TOTALS SINCE
THEN UP TO PRESS TIME AND POSSIBLY PUSHING AN INCH FOR A 12 HR
TOTAL 00Z-12Z THIS MORNING. GAGE OBSERVATIONS ARE ON A SLIGHTLY
STEEPER GLIDE PATH WITH THE LATEST FORECASTS AND ON TRACK FOR OF A
HIGH CONFIDENCE MODERATE STAGE ON THE TITTABAWASSEE...AND
CHALLENGE FOR MAJOR STAGE. OVERNIGHT RAINFALL DISTRIBUTION SHOULD
ALSO KEEP THE CASS RIVER ON PACE TO MATCH THE FORECAST UPDATED
LAST EVENING FOR FLOOD STAGE AT FRANKENMUTH DURING THE MORNING.
DOWNSTREAM ON THE SAGINAW...THERE IS MORE TIME TO ASSESS THE TOTAL
BASIN COLLECTION IN UPCOMING FORECASTS.

CLIMATE...

SNOWIEST WINTER SEASON

CITY       2013-2014        RECORD
FLINT       82.6"      82.9" (1974-75)
DETROIT     91.7"      93.6" (1880-81)

LOW MAX RECORDS FOR APRIL 15:

DTW 36 (1904)
FNT 35 (1944)
MBS 33 (1944)

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...FLOOD WATCH...MIZ047-MIZ048-MIZ049-MIZ053-MIZ054-MIZ055...UNTIL 8
     PM MONDAY.

LAKE HURON...
     SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
     HURON INCLUDING OUTER SAGINAW BAY...UNTIL 4 PM TUESDAY.

LAKE ST CLAIR...
     SMALL CRAFT ADVISORY...UNTIL 4 PM MONDAY.

MI WATERS OF LAKE ERIE...
     SMALL CRAFT ADVISORY...UNTIL 4 PM MONDAY.

&&

$$

AVIATION.....BT
SHORT TERM...BT
LONG TERM....SF
MARINE.......SF
HYDROLOGY....BT
CLIMATE......SF


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









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