Area Forecast Discussion
Issued by NWS Gaylord, MI

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000
FXUS63 KAPX 171817
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
217 PM EDT FRI OCT 17 2014

.SYNOPSIS...
ISSUED AT 446 AM EDT FRI OCT 17 2014

UPPER LEVEL LOW PRESSURE OVER THE WESTERN LAKES THIS MORNING WILL
CROSS INTO MICHIGAN TODAY...SENDING A COLD FRONT THROUGH THE REGION
BY EVENING. THAT FRONT WILL BRING A ROUND OF SHOWERS FOR MOST AREAS
THIS EVENING INTO TONIGHT...GRADUALLY TAPERING OFF ON SATURDAY AS
HIGH PRESSURE ARRIVES. MUCH OF SUNDAY LOOKS DRY WITH A LITTLE
SUNSHINE...BEFORE ANOTHER ROUND OF SHOWERS ARRIVES SUNDAY NIGHT INTO
MONDAY.

&&

.UPDATE...
ISSUED AT 1143 AM EDT FRI OCT 17 2014

OVERVIEW: POTENT SHORT WAVE ADVANCING INTO THE WESTERN GREAT LAKES
TODAY...PHASING WITH LARGER SCALE TROUGH THAT IS ALREADY IN PLACE
ACROSS THE GREAT LAKES. MAIN VORTICITY CENTER IS ROTATING ACROSS NRN
WISCONSIN ALONG WITH AN INITIAL BATCH OF SHOWERS. AT THE
SFC...LARGER AREA OF LOW PRESSURE IS DEVELOPING ALONG THE
ONTARIO/QUEBEC BORDER WITH A COLD FRONT STRETCHING DOWN THROUGH
EASTERN UPPER MICHIGAN AND ON INTO NRN WISCONSIN. MEANWHILE...DEEPER
MOISTURE AND WIDESPREAD PRECIP HAS ROTATED UP ACROSS ONTARIO ALONG
THE NRN SIDE OF THE LARGER SCALE TROUGH...BUT IS CURRENTLY IN THE
PROCESS OF PIVOTING BACK DOWN INTO NRN MICHIGAN.

REST OF TODAY...POTENT SHORT WAVE WILL SWING DOWN INTO LOWER
MICHIGAN THROUGH THE COURSE OF THE AFTERNOON INTO THE EARLY EVENING
HOURS. ATTENDING BATCH OF SHOWERS WILL ALSO ROTATE INTO NRN LOWER
MICHIGAN AND LIKELY EXPAND ACROSS NRN LOWER MICHIGAN AS CORE OF
COLDER AIR (-19C TO -22C AT 500 MB) COMES IN ALOFT AT PEAK
"HEATING." SO...DRIZZLE...WILL GIVE WAY TO INCREASING SHOWER CHANCES
ACROSS NRN LOWER MICHIGAN AS WE GO THROUGH THE AFTERNOON HOURS. FOR
EASTERN UPPER MICHIGAN...MORE WIDESPREAD PRECIP WILL START TO PIVOT
BACK INTO EASTERN UPPER MICHIGAN THROUGH THE AFTERNOON ALSO BRINGING
INCREASING PRECIP CHANCES UP THAT WAY.

THUNDER CHANCES...WITH -19C TO -22C 500 MB CORE OF AIR SLIDING DOWN
THROUGH CENTRAL LOWER MICHIGAN AT PEAK HEATING AND POCKET OF H7-H5
LAPSE RATES PUSHING 7C/KM...CANNOT RULE THE POSSIBILITIES OF SOME
THUNDER ACROSS PARTS OF NRN LOWER MICHIGAN. DON/T THINK THE CHANCES
ARE VERY HIGH BUT WE ALREADY HAVE IT IN THE FORECAST AND WILL KEEP
IT.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 446 AM EDT FRI OCT 17 2014

...SHOWERS TO INCREASE TODAY/BECOMING WINDIER THIS AFTERNOON...

HIGH IMPACT WEATHER POTENTIAL: GUSTY NORTH TO NORTHWEST WINDS
DEVELOPING THIS AFTERNOON AND CONTINUING TONIGHT.  WIND GUSTS AROUND
40MPH EXPECTED ALONG LAKESHORE AREAS IMPACTED BY NORTHWEST ONSHORE
FLOW. AN ISOLATED THUNDERSTORM POSSIBLE THIS AFTERNOON COINCIDENT
WITH PASSING OF UPPER LEVEL COLD POOL.

PATTERN SYNOPSIS/FORECAST: DOUBLE BARRELED LOW PRESSURE CENTERS
FLANK THE UPPER GREAT LAKES THIS MORNING....998MB LOW CENTER OVER
FAR WESTERN QUEBEC...WITH AND ELONGATED 999MB LOW OVER NORTHEAST
MINNESOTA/NORTHWEST WISCONSIN.  THE FORMER IS THE SURFACE RESPONSE
OF A NEGATIVE TILT SHORT WAVE TROUGH OVER THE GREAT LAKES/MID
ATLANTIC REGION...WHILE THE SURFACE LOW OVER THE UPPER MIDWEST
ATTACHED TO A COMPACT UPPER LOW OVER NORTHERN MINNESOTA.  STILL
PLENTY OF TRAPPED LOW LEVEL MOISTURE ACROSS NORTHERN MICHIGAN PER
00Z APX RAOB (SATURATED BELOW 775MB)...WHILE DRIER AIR REMAINS
POISED ACROSS THE UPPER MISSISSIPPI VALLEY (00Z MPX/DVN SOUNDINGS
IN PARTICULAR).  "WAVES" OF DRIZZLE HAVE BEEN SWEEPING ACROSS THE
FORECAST AREA FROM WEST TO EAST DURING THE NIGHT...SPOTTY SHOWERS
ALSO LOCATED OVER LAKE HURON.  MORE SUBSTANTIAL RAIN WAS PUSHING
BACK WEST ACROSS NORTHEAST ONTARIO TOWARD LAKE SUPERIOR.  THERE IS
CLEARING PUSHING ACROSS CENTRAL AND SOUTHERN LAKE MICHIGAN.

STRONG PRESSURE FALLS OCCURRING COINCIDENT WITH AND TO THE NORTHWEST
OF THE QUEBEC LOW PRESSURE CENTER (3-4MB/3H)...SUPPORTING DEEPENING
AND A CONTINUED NORTHWARD TRACK TODAY.  NORTHWEST WISCONSIN SURFACE
LOW TRACKING EAST TOWARD AN ELONGATED AXIS OF 2MB/3H PRESSURE FALLS
ACROSS UPPER MICHIGAN/EASTERN WISCONSIN.  EVENTUALLY THESE DISPARATE
FEATURES WILL BECOME DOMINATED BY THE DOWNSTREAM SYSTEM AS IT
ABSORBS THE ENERGY OVER THE UPPER MIDWEST AND FORMS ONE MAIN AREA OF
LOW PRESSURE/CYCLONIC FLOW CENTERED OVER NORTHERN QUEBEC BY
TONIGHT.  THIS PROCESS WILL INCREASE NORTHWEST WINDS ACROSS MICHIGAN
AND PULL COLDER AIR ACROSS THE STATE TONIGHT INTO SATURDAY.

PRIMARY FORECAST CONCERNS: IMPACTS OF ARRIVING SHORT WAVE LATER
TODAY FROM THE WEST...AND OVERALL DETERIORATING WEATHER AS SYSTEMS
CONSOLIDATE INTO ONE (PRECIPITATION AND WIND CONCERNS).  ANY THUNDER
CHANCES BENEATH THE ARRIVING UPPER LEVEL COLD POOL THIS AFTERNOON?

TODAY/TONIGHT...WILL PROBABLY DEALING WITH SOME CONTINUED DRIZZLE OR
A MISTY LIGHT RAIN THIS MORNING AS MOIST LAYER DEPTH INCREASES WITH
APPROACH OF UPSTREAM SHORT WAVE TROUGH.  WILL PROBABLY SEE MORE
SUBSTANTIAL PRECIPITATION START DEVELOPING TOWARD MIDDAY AS STRONGER
FORCING AND COOLER MID LEVEL TEMPERATURES ARRIVE.  SO PERIODS OF
LIGHT RAIN/DRIZZLE TO GIVE WAY TO MORE SHOWERY ACTIVITY HEADING INTO
THE AFTERNOON.  500MB TEMPERATURES FALLING BELOW -20C MAY SUPPORT A
CONVECTIVE COMPONENT TO PRECIPITATION THIS AFTERNOON.  WHILE
INSTABILITY PARAMETERS ARE MINIMAL...DECENT OVERLAP BETWEEN LOW
LEVEL (925-850MB) THETA-E AND DYNAMIC TROPOPAUSE POTENTIAL
TEMPERATURE SUGGESTS AT LEAST SOME ISOLATED THUNDER...WHICH HAD BEEN
OCCURRING ACROSS MINNESOTA WITHIN THE MID LEVEL COLD POOL EARLIER
TONIGHT.  WINDS WILL BEGIN TO RAMP UP DURING THE LATTER HALF OF THE
AFTERNOON WITH THE SHIFT TO NORTHWEST.  WIND GUSTS 25-30MPH EXPECTED
WITH GUSTS 30-40MPH ALONG SHORELINE AREAS IMPACTED BY ONSHORE FLOW
IN NORTHWEST WINDS.

SHOWERS WILL CONTINUE TONIGHT AS SHORT WAVE TROUGH PASSES BY...850MB
TEMPERATURES DROPPING BELOW ZERO AND A DECREASE IN OVER WATER
STABILITY WILL ALLOW FOR SOME LAKE ENHANCEMENT TO OCCUR.  WON`T RULE
OUT SOME SNOWFLAKES MIXING IN ESPECIALLY ACROSS EASTERN UPPER
OVERNIGHT...BUT WON`T ADD TO THE FORECAST AT THIS POINT.  GUSTY
NORTH TO NORTHWEST WINDS TO CONTINUE.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 446 AM EDT FRI OCT 17 2014

...TYPICAL OCTOBER WEATHER RIGHT ON INTO NEXT WEEK...

HIGH IMPACT WEATHER POTENTIAL: GALE POTENTIAL CONTINUES ON MOST OF
THE LAKES THROUGH SATURDAY.

PATTERN SUMMARY/EVOLUTION: SOUNDING LIKE A BROKEN RECORD HERE...BUT
NO REAL CHANGES ARE EXPECTED TO THE OVERALL GOING PATTERN WE HAVE
SEEN OF LATE. SIMPLY PUT...THAT MEANS AN OVERALL FLAVOR OF UPPER
TROUGHING ACROSS THE GREAT LAKES...REINFORCED AT VARIOUS TIMES BY
ADDITIONAL SHORTWAVE ENERGY DIVING OUT OF CENTRAL CANADA. THE FIRST
OF THOSE REINFORCING SHOTS ARRIVES INTO SATURDAY...WITH ANOTHER
TOWARD MONDAY...BEFORE SOME BETTER NEWS BEGINS TO ARRIVE TOWARD MID
AND LATE WEEK AS HEIGHTS JUST TO OUR WEST AT LEAST BRIEFLY BEGIN TO
REBOUND...ALL WHILE LOW LEVEL RIDGING TAKES A FIRM GRIP ON NORTHERN
MICHIGAN. WITH THAT SAID...CONFIDENCE IS RATHER LOW THAT FAR OUT
WITH REGARD TO JUST HOW MUCH RESIDUAL UPPER TROUGHING WILL RESIDE
OVER THE EASTERN CONUS...WHICH COULD AND WILL HAVE A BIG INFLUENCE
ON OUR LOCAL ABILITY TO SEE ANY WARMER TEMPS.

BREAKING IT ALL DOWN...THINGS LOOK LIKE THIS:

SATURDAY: WELCOME BACK FALL! MUCH COLDER AIR WILL BE WELL ENTRENCHED
OVERHEAD TO START THE DAY...WITH DEEP CYCLONIC FLOW/MOISTURE AND
EXCELLENT LAKE INSTABILITY PROMOTING WIDESPREAD SHOWERS FOR MANY
AREAS...AIDED BY STRONGER FLOW TO ADVECT THE PRECIP FARTHER INLAND.
THAT PROCESS WILL BREAK DOWN THROUGH MIDDAY AND THE AFTERNOON AS
SHARP DRYING ALOFT SPREADS IN...WITH MOISTURE THINNING DOWN BELOW
875MB BY 18Z AND FURTHER LOWERING THEREAFTER. AS IS OFTEN THE
CASE...AND GIVEN SUCH CHILLY LOW LEVEL TEMPS (I.E. GREAT OVER-WATER
INSTABILITY)...SUSPECT MOMENTUM WILL BE ENOUGH TO MAINTAIN SOME
SHOWERS THROUGH EARLY AFTERNOON BUT LIKELY ENDING THEREAFTER AS
INCREASINGLY ANTICYCLONIC FLOW ARRIVES AND MOISTURE THINS EVEN MORE.
DEFINITELY A CHILLY/BREEZY DAY WITH SOME HIGHER TERRAIN SPOTS
PERHAPS STRUGGLING TO EVEN HIT 40...WITH LOW/MID 40S ELSEWHERE. AS
HAS BEEN ALLUDED TO RECENTLY...THE CHANCE FOR A LITTLE SNOW TO MIX
IN SATURDAY MORNING ISN`T ZERO GIVEN SUCH A CHILLY AIR MASS AND
MELTING LEVELS JUST BELOW 2KFT.

SATURDAY NIGHT-SUNDAY: A MUCH QUIETER PERIOD ON TAP AS LOW LEVEL
RIDGING BUILDS ACROSS THE AREA ALONG WITH A SIGNIFICANTLY DRIER
AIR MASS. GIVEN THE SETUP WITH PERSISTENT SHALLOW INSTABILITY...HAVE
LITTLE DOUBT WE WILL BE DEALING WITH PESKY REMNANT LAKE CLOUD COVER
THROUGH THE NIGHT AND PROBABLY EVEN INTO PART OF SUNDAY AS THE LOW
LEVEL FLOW BACKS FROM NORTHERLY TO SOUTHWESTERLY. THAT OF COURSE
MAKES TEMPS DARN NEAR IMPOSSIBLE SATURDAY NIGHT BUT GIVEN THE COLD
START AND TYPICAL NATURE FOR LAKE CLOUDS TO THIN AT TIMES FARTHER
INLAND OVERNIGHT...SUSPECT SOME SPOTS WILL EASILY END UP DOWN IN THE
20S. WHATEVER CLOUDS ARE STILL AROUND SUNDAY MORNING SHOULD SLOWLY
THIN WITH LOW LEVEL WARM ADVECTION KICKING INTO GEAR...BUT OF COURSE
JUST IN TIME FOR ADDITIONAL THICKER MID/HIGH CLOUDS TO ARRIVE DURING
THE AFTERNOON...AHEAD OF THE NEXT UPPER WAVE DIGGING INTO THE UPPER
MIDWEST.

SUNDAY NIGHT-MONDAY: CLASSIC CLIPPER SYSTEM STILL ON TRACK TO MAKE
AN APPEARANCE TO START THE NEW WORK WEEK...AS ANOTHER FAIRLY ROBUST
SHORTWAVE DIGS THROUGH THE NORTHERN LAKES. STILL A TOUCH OF
PLACEMENT DISAGREEMENT WITH VARIOUS PIECES OF GUIDANCE...BUT THE
OVERALL TREND IS WELL ESTABLISHED FOR A BRIEF BURST OF WARM
ADVECTION PRECIP SOMETIME LATER SUNDAY NIGHT...FOLLOWED BY SOME
ADDITIONAL DIURNALLY-DRIVEN AND LAKE ENHANCED SHOWERS BENEATH THE
CORE OF COOLEST AIR ALOFT INTO MONDAY AFTERNOON. GOING LIKELY POPS
CAN PROBABLY STAND A BOOST SIMPLY BASED ON THE PATTERN...THOUGH
REMNANT UNCERTAINTY REGARDING THE EXACT PLACEMENT OF THE BETTER
FORCING MANDATES LEAVING THAT TO LATER SHIFTS. TEMPS ON MONDAY ARE
CERTAINLY TROUBLESOME...BUT GET THE FEELING MANY SPOTS WILL END UP
ON THE COOLISH SIDE...STRUGGLING THROUGH THE LOWER HALF OF THE 40S
WITH BOUTS OF SHOWERS.

MONDAY NIGHT-THURSDAY: COULD END UP SEEING A FEW LINGERING SHOWERS
INTO MONDAY NIGHT...PENDING THE DEPARTURE TIMING OF THE UPPER
TROUGH. LATEST GUIDANCE TRENDS SUGGEST A SLOWER EVOLUTION MAY BE THE
WAY TO GO...BUT CONFIDENCE NOT EXACTLY HIGH. IN ANY CASE...THE
OVERALL TREND HEADING INTO MIDWEEK WILL BE ONE OF INCREASING
SUNSHINE AND SLOWLY MODERATING TEMPERATURES. THERE IS CONSIDERABLY
UNCERTAINTY REGARDING JUST HOW MUCH UPPER ENERGY WILL CLOSE OFF OVER
THE MID ATLANTIC STATES TOWARD MIDWEEK...BUT BASED ON THE TIME OF
YEAR AND RECENT TRENDS...HIGHLY SUSPECT WE ARE LOOKING AT YET
ANOTHER CLOSED SYSTEM DRIFTING THROUGH THE EASTERN CONUS FOR WHAT
COULD BE A SEVERAL DAY STRETCH INTO LATE WEEK. IN FACT...IT`S NOT
COMPLETELY INCONCEIVABLE THAT THAT FEATURE COULD END UP FARTHER WEST
AS MANY HAVE DONE IN RECENT MEMORY - AN IDEA OFFERED UP BY SEVERAL
GFS ENSEMBLE MEMBERS AND EVEN THE 16/18Z OPERATIONAL GFS. WILL TAKE
THE OPTIMISTIC ROUTE AT THIS JUNCTURE...AS SUGGESTED BY PERSISTENCE
FROM THE ECMWF...ALLOWING FAIRLY ROBUST LOW LEVEL RIDGING FROM
HUDSON BAY TO TAKE OVER INTO MID AND LATE WEEK. THAT RIDGE AND ITS
ASSOCIATED QUITE DRY CANADIAN AIR SHOULD DELIVER SOME MUCH-DESERVED
SUNSHINE FOR THE LATTER PERIODS OF THE FORECAST...THOUGH WITH
SHALLOW MIXING NOT DOING A WHOLE LOT TO PROMOTE MUCH WARMER TEMPS.
STILL...READINGS PUSHING BACK TOWARD CLIMO LEVELS (MAINLY LOW/MID
50S) LOOK DOABLE BY WED-THU...BUT WITH CERTAINLY SOME CHILLY MID
FALL MORNINGS EXPECTED WITH LIGHT WINDS/CLEAR SKIES AND DRY AIR
OVERHEAD.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 216 PM EDT FRI OCT 17 2014

CONDITIONS CONTINUE TO TEETER BETWEEN IFR AND MVFR ACROSS NRN
LOWER MICHIGAN. BUT LOW PRESSURE AND A COLD FRONT WILL SWING
ACROSS NRN LOWER MICHIGAN OVER THE NEXT FEW HOURS...BRINGING
INCREASING SHOWERS AND CIGS DIPPING BACK BELOW 1K FEET THROUGH THE
REST OF THE AFTERNOON AND TONIGHT. RAIN SHOWERS REALLY TAKE OFF
ACROSS NW LOWER MICHIGAN THIS EVENING AS MUCH COLDER AIR SPILLS
INTO THE REGION AND GENERATE WIDESPREAD LAKE EFFECT RAIN SHOWERS.
IN ADDITION...GUSTY NW WINDS DEVELOP THIS EVENING WITH GUSTS
RUNNING 25 TO 30 KNOTS THROUGH THE NIGHT. WINDS WILL DIMINISH A
BIT FOR SATURDAY (STILL RUNNING 10 TO 20 KNOTS). BUT MUCH DRIER
AIR SPREADS INTO THE REGION SATURDAY AND WILL BRING A QUICK END TO
THE SHOWERS AND BRING SOME IMPROVING CIGS.

&&

.MARINE...
ISSUED AT 446 AM EDT FRI OCT 17 2014

WINDS WILL INCREASE ACROSS THE UPPER GREAT LAKES THIS AFTERNOON AND
TONIGHT...AS LOW PRESSURE OVER NORTHWEST WISCONSIN CROSSES LOWER
MICHIGAN TODAY.  THIS WILL SHIFT WINDS AROUND TO THE NORTHWEST AND
TIGHTEN THE PRESSURE GRADIENT ACROSS NORTHERN MICHIGAN.  EXPECT
WINDS TO RAMP UP 20-30KTS BY MID/LATE AFTERNOON ACROSS MOST NEARSHORE
ZONES...AND GALES BY EVENING FOR WHITEFISH BAY AND NORTHERN LOWER
NEARSHORE ZONES (WARNINGS WILL RUN THROUGH SATURDAY).


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EDT SUNDAY
     FOR LHZ346-349.
     GALE WARNING FROM 6 PM THIS EVENING TO 6 PM EDT SATURDAY FOR
     LHZ345-347-348.
LM...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EDT SUNDAY
     FOR LMZ341.
     GALE WARNING FROM 6 PM THIS EVENING TO 6 PM EDT SATURDAY FOR
     LMZ323-342-344>346.
LS...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EDT SUNDAY
     FOR LSZ322.
     GALE WARNING FROM 6 PM THIS EVENING TO NOON EDT SATURDAY FOR
     LSZ321.

&&

$$

UPDATE...ADAM
SYNOPSIS...LAWRENCE
SHORT TERM...JPB
LONG TERM...LAWRENCE
AVIATION...ADAM
MARINE...JPB





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