000
FXUS63 KAPX 050456
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1156 PM EST WED DEC 4 2013

.SYNOPSIS...
ISSUED AT 339 PM EST WED DEC 4 2013

LOW PRESSURE OVER THE UPPER MISSISSIPPI VALLEY WILL MOVE INTO
ONTARIO OVERNIGHT...AND CONTINUE THE WARM TEMPERATURES OVER THE
STATE. AS THE COLD FRONT BEGINS TO PUSH INTO THE STATE...LATE
TONIGHT INTO THURSDAY MORNING...THE RAIN WILL CHANGE TO SNOW IN
WESTERN UPPER MICHIGAN...BUT KEEPING EASTERN UPPER AND ALL OF LOWER
MICHIGAN WARM ENOUGH FOR RAIN. DRIER AIR WILL MOVE INTO THE STATE
THURSDAY MORNING STOPPING THE PRECIPITATION. THEN ARCTIC AIR WILL
SETTLE INTO THE AREA BY THURSDAY AFTERNOON AND LASTING INTO THIS
WEEKEND. THIS WILL RESULT IN LAKE EFFECT SNOW SHOWERS FOR EASTERN
UPPER AND NORTHWEST LOWER MICHIGAN. MORE COLD AIR AND ADDITIONAL
SNOW CHANCES ARE EXPECTED TO CONTINUE RIGHT INTO NEXT WORK WEEK.

&&

.UPDATE...
ISSUED AT 1150 PM EST WED DEC 4 2013

TEMPERATURES CONTINUE TO CLIMB OUT AHEAD OF THE APPROACHING COLD
FRONT DUE TO ARRIVE IN ANOTHER FEW HOURS. THE RAIN AND DRIZZLE
CONTINUES TO RETREAT TO THE NORTH...AND TEMPERATURES HAVE RISEN
ABOVE FREEZING ACROSS EASTERN UPPER ENDING THE FREEZING RAIN
THREAT. THIS LINES UP WELL WITH THE ENDING OF THE SPECIAL WEATHER
STATEMENT AT MIDNIGHT. THE FOG STILL PERSISTS BUT IS NOT AS DENSE
AS IT WAS EARLIER...AND SHOULD DISSIPATE BEHIND THE COLD FRONT.

UPDATE ISSUED AT 801 PM EST WED DEC 4 2013

DID PUT OUT THE SPECIAL WEATHER STATEMENT DUE TO EXPECTED LIGHT
FREEZING RAIN ACROSS EASTERN UPPER OVER THE NEXT COUPLE OF HOURS.
ALSO ADDED IN THUNDER NEAR SAGINAW BAY COUNTIES AS A FEW STRIKES
POPS UP DOWN THAT WAY AS THE WARM AIR CONTINUES TO SURGE
NORTHWARD.

UPDATE ISSUED AT 632 PM EST WED DEC 4 2013

NO MAJOR UPDATES NECESSARY TO THIS POINT WITH WARMER AIR AND THE
BATCH OF RAIN MOVING IN FROM THE SOUTH. THE RAIN HAS LIFTED THE
FOG IN MOST AREAS...AT LEAST TO THE POINT TO WHICH IT IS NOT DENSE
ANYMORE. WILL HAVE TO EVALUATE EASTERN UPPER AND POSSIBLY ISSUE
ANOTHER SPECIAL WEATHER STATEMENT ADVISING OF LIGHT ICING.

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 339 PM EST WED DEC 4 2013

THE STORM SYSTEM WHICH WAS ORGANIZING OVER THE PLAINS SINCE TUESDAY WILL
CONTINUE TO WORK NORTH INTO WISCONSIN THIS EVENING...BEFORE LIFTING
INTO JAMES BAY THURSDAY. THIS PATTERN WILL ALLOW MILD TEMPS AND
ABOVE FREEZING DEW PTS TO CONTINUE STREAMING OVR THE NRN LAKES
THROUGH THE OVERNIGHT HOURS. CURRENT SFC OBS SHOW A MAJORITY OF NRN
MI HAS ALREADY WARMED ABOVE FREEZING...EXCEPT FOR ERN UPPER MICHIGAN
WHERE MANY LOCATIONS TEMP/DEW PTS ARE LINGERING IN THE MID AND
UPPER 20S. MODEL SOUNDINGS AND TEMP PROGS CONTINUE TO SUPPORT
WARMING TEMPS AND DEW PTS ACRS THE ENTIRE CWA TONIGHT WITH 925MB
TEMPS WARMING TO BTWN 4C/8C WHILE 850MB TEMPS WARM TO AROUND 4C.
MODEL SOUNDINGS SHOW ABOVE FREEZING LAYER EXTENDING FROM THE SFC
THROUGH 8KFT ACRS NRN LWR UNTIL BTWN 09Z AND 12Z WHEN THE ABOVE
FREEZING LAYER FALLS TO UNDER 3K FT. HOWEVER OVER ERN UPPER...
WARMING WILL TREND MUCH SLOWER WITH THE DEPTH OF THE SFC BASED COLD
LAYER REMAINING DEEPER THAN 3K FT TIL BTWN 21Z AND 00Z...BEFORE
FINALLY WARMING ABV FREEZING ARND 03Z.

OVERALL EXPECT WINTRY MIXED PCPN TO LINGER OVER ERN UPPER THIS
EVENING IN THE FORM OF LIGHT SNOW AND FREEZING DRIZZLE...TRENDING
TOWARD DRIZZLE AND LIGHT RAIN OVERNIGHT AS THE SFC BASED COLD POOL
WARMS ABOVE FREEZING. FOR NRN LWR...WILL MENTION ALL LIQUID PCPN
ACROSS NORTHEAST LWR THROUGH THE OVERNIGHT AS MODEL SOUNDINGS SHOW
WARM AIR LINGERING THROUGH 12Z THURSDAY. FOR NORTHWEST LOWER...MODEL
SOUNDINGS SHOW COLDER AIR FILTERING BACK INTO THE WRN GREAT LAKES
BTWN 09Z AND 12Z ON THE BACKSIDE OF THE EXITING PLAINS SYSTEM...SO
WILL MENTION WINTRY MIX OVR NWR TWD DAWN. PCPN ADVANCING INTO THE
NRN LAKES THIS EVENING IN ADVANCE OF APPROACHING PLAINS SYSTEM...
WILL QUICKLY TREND TOWARD DRIZZLE ARND 06Z AS MID AND UPPER LVL MSTR
STRIP OUT WHILE LOW LVL MSTR REMAINS SATURATED.

AM CONCERNED ABOUT FREEZING DRIZZLE/RAIN OVER ERN UPPER AND STRAITS
REGION THIS EVENING UNTIL SFC WARMS...MAY ISSUE AN ADVSY FOR AREAS
NORTH OF THE STRAITS THIS EVENING. ALSO...THERE IS A CONCERN FOR
DENSE FOG OVER MUCH OF NRN LWR MICHIGAN TONIGHT. CURRENT SFC OBS
ALREADY SHOWING SEVERAL LOCATIONS WITH VSBY 1/2 MILE OR LESS. WITH
THE SFC TEMP OF THE SNOW NOW ARND FREEZING AND EXPECTED TO WARM
SLIGHTLY...WOULD EXPECT WIDESPREAD FOG TO REMAIN AN ISSUE FOR MUCH
OF NRN MI.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 339 PM EST WED DEC 4 2013

OVERVIEW: FAIRLY AMPLIFIED/BLOCKY THREE-WAVE PATTERN IN PLACE ACROSS
THE NRN HEMISPHERE WITH SHARP/BLOCKING RIDGE IN THE EASTERN PACIFIC
TO THE GULF OF ALASKA. DOWNSTREAM LONG WAVE TROUGH ENCOMPASSES MUCH
OF NOAM WITH VERY COLD UNSEASONABLE AIR PLUNGING INTO THE WESTERN
CONUS AND NRN PLAINS ON THE HEELS OF A STRONG SHORT WAVE DIGGING
INTO THE PLAINS. BAGGY LOW PRESSURE STRETCHED ALONG THE MISSISSIPPI
RIVER VALLEY THIS MORNING. SFC WARM FRONT RESIDES ROUGHLY ACROSS
ILLINOIS/INDIANA/OHIO...WHILE WARM NOSE ALOFT HAS BEEN MAKING STEADY
NORTHWARD PROGRESS INTO THE GREAT LAKES (12 APX SOUNDING HAD A THIN
>0C WARM NOSE CENTERED AROUND 850 MB). TEMPS WILL CONTINUE TO CLIMB
THROUGH THIS EVENING BEFORE PLUNGING BACK DOWN TONIGHT AND TURNING
COLD TO WRAP UP THE WORK WEEK (SEE SHORT TERM FORECAST DISCUSSION).

THURSDAY THROUGH FRIDAY...SECONDARY COLD FRONT EARLY AND WSW COLD
ADVECTION ON THE BACKSIDE OF THE FRONT WITH A BIG TRANSITION DURING
THE DAY THURSDAY...AS H8 TEMPS START A FEW DEGREES EITHER SIDE OF 0C
EARLY THURSDAY MORNING TO -8C TO -12C BY LATE AFTERNOON. WELL
DEFINED DRY SLOT PUNCHING UP THROUGH THE REGION WILL ALREADY BE IN
PLACE THURSDAY MORNING AND THERE WONT BE MUCH GOING AT LEAST THROUGH
THE MORNING HOURS OTHER THAN PERHAPS A THIN CORRIDOR OF CLOUDS
MOVING THROUGH EARLY ALONG THE SECONDARY COLD FRONT. LAKE EFFECT
POSSIBILITIES IMPROVE THURSDAY AFTERNOON AND THURSDAY NIGHT AS 900
MB TEMPS (TOP OF THE FORECAST MIXED LAYER) SETTLE DOWN AROUND -12C
AND LOW LEVEL MEAN FLOW SETTLES INTO A WESTERLY DIRECTION. LAKE SFC
TEMPS HAVE BEEN FALLING RAPIDLY IN RECENT DAYS...DOWN AROUND 6C OR
SO ON AVERAGE FOR NRN LAKE MICHIGAN AND EASTERN LAKE SUPERIOR. BUT
RESULTING "DELTA T/S" IN THE HIGH TEENS TO NEAR 20C ARE CERTAINLY
ENOUGH FOR LAKE EFFECT SNOWS. HOWEVER...GUIDANCE CONTINUES TO
ADVERTISE A BIG WEDGE OF DRY AIR GETTING STRUNG OUT FROM THE PLAINS
ACROSS THE LOWER LAKES WHICH WILL THROTTLE LAKE CONVECTION. IN
ADDITION...STRONG SUBSIDENCE AND RESULTING INVERSION HEIGHTS GETTING
SQUASHED TO LESS THAN 5K FEET WILL FURTHER HAMPER LAKE EFFECT SNOWS
THROUGH FRIDAY. ACROSS UPPER MICHIGAN...WESTERLY FLOW REGIME (OR
EVEN WSW REINFORCED BY PERSISTENT LAKE AGGREGATE TROUGH LATCHED ON
TO THE LAKE SUPERIOR SHORELINE) WILL KEEP MOST LAKE CONVECTION OUT
CHIP/MACK COUNTIES. UPSHOT...ANTICIPATE ONLY LIGHT LAKE EFFECT SNOW
SHOWERS LATER THURSDAY THROUGH FRIDAY MAINLY IMPACTING NW LOWER
MICHIGAN AND ESPECIALLY NORTH OF M-72 WITH A BETTER FETCH ACROSS THE
LAKE. HAVE SCT-NMRS SNOW SHOWERS BUT LIGHT ACCUMULATIONS DESPITE THE
COLD AIR (LESS THAN AN INCH FOR EACH FORECAST PERIOD).

FRIDAY NIGHT THROUGH SATURDAY...LARGE EXPANSE OF HIGH PRESSURE STILL
LOOKING TO BUILD FROM THE PLAINS EASTWARD ACROSS THE GREAT LAKES BY
SATURDAY EVENING. LOW LEVEL MEAN FLOW MAY VEER SLIGHTLY MORE WNW AND
DRAG A LITTLE BETTER LOW LEVEL MOISTURE INTO NRN MICHIGAN. FORECAST
SOUNDINGS SHOW AN UPTICK IN INVERSION HEIGHTS FRIDAY NIGHT INTO
SATURDAY NOT SO MUCH IN RESPONSE TO ANY SYNOPTIC FORCING MECHANISM
BUT RATHER BETTER COLD ADVECTION AROUND 850MB DRAGGING A POCKET OF
-18C TO -22C AIR INTO NRN MICHIGAN. SO...MIGHT BE ENOUGH TO PRODUCE
AN UPTICK IN WESTERLY FLOW SNOW SHOWERS AND SOME ACCUMULATIONS
DURING THIS TIME. BUT BY SATURDAY NIGHT...HIGH PRESSURE STRETCHES
OUT ACROSS THE GREAT LAKES. WEAKENING WIND REGIME

SUNDAY AND MONDAY...ATTENTION THEN TURNS TO OUR NEXT POTENTIAL STORM
SYSTEM. ANOTHER FAIRLY STRONG SHORT WAVE (WAY UP IN THE NW
TERRITORIES TODAY) SLATED TO DIG INTO THE SW STATES THIS WEEKEND
THEN PHASE WITH THE NRN STREAM AND EJECT THROUGH THE PLAINS AND INTO
THE GREAT LAKES SUNDAY THROUGH MONDAY. ASSOCIATED SFC LOW DEVELOPS
AND DEEPENS OVER THE LOWER MISSISSIPPI RIVER VALLEY AND LIFTS NE
THROUGH SRN LOWER MICHIGAN. OBVIOUSLY A LOT HAS TO HAPPEN BETWEEN
NOW AND THEN AND AS MENTIONED THIS NEXT WAVE IS CURRENTLY WAY UP IN
THE NW TERRITORIES. HOWEVER...MEDIUM RANGE GUIDANCE ENVELOPE HAS
TIGHTENED UP OVER THE LAST FEW RUNS WITH THIS SYSTEM...GIVING AT
LEAST SOME CONFIDENCE THAT WE GET A SNOW MAKER EARLY NEXT WEEK.
CURRENT SOLUTIONS DO NOT DEVELOP A PARTICULARLY STRONG SYSTEM...
AROUND 1000 MB AS IT MOVES THROUGH AND AS SUCH DO NOT FEEL COMPELLED
TO HIGHLIGHT ANY THREATS IN THE HAZARDOUS WEATHER OUTLOOK. BUT IT
HAS POTENTIAL FOR ACCUMULATING SNOW AND SOME GUSTY WINDS AND WILL
NEED TO BE WATCHED OVER THE NEXT FEW DAYS.

TUESDAY AND WEDNESDAY...BEHIND THAT SYSTEM...TURNS VERY COLD ONCE
AGAIN WITH WIDE EXPANSE OF -20C OR COLDER H8 AIR SETTLING INTO THE
NRN PLAINS TO GREAT LAKES. COLD...WITH LAKE SNOWS TO WRAP UP THE
EXTENDED FORECAST.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1150 PM EST WED DEC 4 2013

THE STORM SYSTEM TO OUR WEST WILL DRAG A COLD FRONT ACROSS THE
REGION BETWEEN 06-09Z. CIGS AND VSBYS OUT AHEAD OF THE COLD FRONT
WILL CONTINUE TO BE IFR...THOUGH MVFR CIGS ARE ALSO POSSIBLE.
BEHIND THE FRONT CIGS ARE EXPECTED TO IMPROVE TO MVRF THEN LOW
END VFR THURSDAY MORNING. WINDS WILL SHIFT INTO THE SOUTHWEST AND
PICK UP EARLY THURSDAY AND BE QUITE GUSTY THROUGH THE DAY. LAKE
EFFECT SNOW SHOWERS POSSIBLY IN THE VICINITY THURSDAY...BUT THE
AIRMASS IS A RATHER DRY ONE...SO NO RESTRICTIONS TO CIGS/VSBYS
EXPECTED...EXCEPT FOR POSSIBLE MVFR TOWARD THE VERY END OF THE TAF
PERIOD.

&&

.MARINE...
ISSUED AT 339 PM EST WED DEC 4 2013

STRONG COLD FRONT WILL SWING THROUGH NRN MICHIGAN LATE THIS
EVENING AND OVERNIGHT. BEHIND THE FRONT...A PERIOD OF GUSTY
SOUTHWEST WINDS WILL DEVELOP...PRIMARILY IMPACTING LAKE MICHIGAN
WITH A LONGER FETCH OVER THE LAKES. GALE FORCE GUSTS WILL BE
MARGINAL (AROUND 35 KNOTS)...BUT CLOSE ENOUGH TO WARRANT ISSUING
GALE WARNING FOR THE NEARSHORE AREAS OF NRN LAKE MICHIGAN
OVERNIGHT THROUGH THURSDAY. WINDS VEER MORE WESTERLY AND EASE A
BIT AS WE GO THROUGH THE DAY THURSDAY...AND FURTHER DIMINISH
THURSDAY NIGHT AND FRIDAY. GALES SHOULD END BY LATER
THURSDAY...ALTHOUGH SOME SMALL CRAFT ADVISORY CONDITIONS WILL
LIKELY PERSIST.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 5 PM EST THURSDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST THURSDAY FOR LMZ323.
     GALE WARNING UNTIL 5 PM EST THURSDAY FOR LMZ341-342-344>346.
LS...SMALL CRAFT ADVISORY UNTIL 5 PM EST THURSDAY FOR LSZ321-322.

&&

$$

UPDATE...AS
SYNOPSIS...JL
SHORT TERM...SR
LONG TERM...BA
AVIATION...AS
MARINE...SR