Area Forecast Discussion
Issued by NWS Gaylord, MI

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000
FXUS63 KAPX 162313
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
713 PM EDT THU OCT 16 2014

.SYNOPSIS...
ISSUED AT 415 PM EDT THU OCT 16 2014

UPPER LEVEL LOW PRESSURE WILL CONTINUE TO MEANDER ACROSS THE REGION
TONIGHT...PROVIDING A FEW PERIODS OF DRIZZLE AND PERHAPS A COUPLE
SHOWERS AT TIMES. MUCH BETTER RAIN CHANCES WILL ARRIVE LATER FRIDAY
INTO FRIDAY NIGHT...AS A STRONG COLD FRONT PUSHES THROUGH THE GREAT
LAKES. THAT FEATURE WILL USHER IN MUCH COLDER CONDITIONS FOR THE
WEEKEND...BUT WITH RAIN CHANCES DIMINISHING BY SATURDAY NIGHT AND
SUNDAY AS HIGH PRESSURE ARRIVES.

&&

.SHORT TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 415 PM EDT THU OCT 16 2014

OVERVIEW: SPLIT FLOW PATTERN ACROSS EASTERN NORTH AMERICA WITH A
DEEP CUT-OFF LOW SPANNING MUCH OF THE EASTERN CONUS AND CIRCULATION
CENTER ROUGHLY OVER LAKE ERIE. STRONG W/SW UPPER LEVEL FLOW BARRELING
INTO THE WEST COAST WITH ANOTHER PACIFIC SHORT WAVE ADVANCING THROUGH
THE NRN PLAINS. THIS NEXT WAVE WILL PHASE WITH CURRENT CUT-OFF OVER
THE GREAT LAKES OVER THE NEXT 12 TO 24 HOURS AND CARVE OUT ANOTHER
DEEP TROUGH OVER THE REGION LATE FRIDAY INTO THE WEEKEND.

BUT FOR TONIGHT...WE CONTINUE TO DEAL WITH DEEP MOISTURE/LOW CLOUDS
ROTATING ACROSS THE GREAT LAKES AROUND THE UPPER LOW...GENERATING
SOME DRIZZLE/SPOTTY SHOWERS FROM TIME TO TIME. POCKET OF COLD AIR
ALOFT WITH THE UPPER LOW (-17C TO -19C AT 500 MB) SITS ACROSS THE
EASTERN PART OF LOWER MICHIGAN. ALONG WITH DAYTIME "HEATING"...SPOTTY
SHOWERS HAVE FINALLY DEVELOPED OVER NORTHEAST LOWER MICHIGAN.
EXPECT THIS ACTIVITY TO SLOWLY FIZZLE OUT THIS EVENING. HOWEVER...
FORECAST SOUNDINGS REVEAL A FAIRLY DEEP SATURATED LOW LEVEL UP
THROUGH AT LEAST 850 MB THROUGHOUT THE NIGHT SUGGESTING DRIZZLE
WILL REMAIN A GOOD POSSIBILITY PARTICULARLY OVERNIGHT AS WE START
TO SEE SOME QG FORCING PRESSING IN FROM THE WEST.

OTHERWISE...TEMPS DONT GO VERY FAR FROM THIS AFTERNOONS READINGS...
DIPPING INTO THE UPPER 40S TO LOWER 50S.

.LONG TERM...(FRIDAY THROUGH THURSDAY)
ISSUED AT 415 PM EDT THU OCT 16 2014

...CONTINUED UNSETTLED AND TRENDING COOLER...

HIGH IMPACT WEATHER POTENTIAL: GALE FORCE WIND POTENTIAL FRIDAY
NIGHT THROUGH SATURDAY.

PATTERN SUMMARY/FORECAST: LONGWAVE PATTERN REMAINS RATHER STAGNANT
THROUGH THE UPCOMING LONG TERM FORECAST PERIOD...WITH LONGWAVE
TROUGHING ANCHORED NEAR 150W /GULF OF ALASKA/ WHICH TELECONNECTS TO
DOWNSTREAM RIDGING OVER WESTERN NOAM...AND EASTERN TROUGHING...
ALLOWING FOR THE NORTHERN STREAM TO DOMINATE CONDITIONS OVER THE
GREAT LAKES REGION.  THE BIGGEST CHANGE IN THIS COMPARED TO WHAT WE
HAVE SEEN OF LATE IS THE WESTERN RIDGE...WHICH WILL HELP REORIENT
THE FLOW ALOFT TO NORTHWESTERLY...ALLOWING A RENEWAL OF COLDER THAN
NORMAL TEMPERATURES FOR THE LONG TERM FORECAST PERIOD. THE
DEVELOPING DOMINANCE OF THE NORTHERN STREAM SUGGESTS LITTLE THREAT
FOR HIGH IMPACT WEATHER OUTSIDE OF MARINE GALE POTENTIAL UNDER
STRENGTHENING POLAR FLOW.

THE STRENGTH OF EACH OF THESE LONGWAVE FEATURES WILL VARY SOME
THROUGH THE FORECAST PERIOD WITH EACH SUCCESSIVE DEEPENING OF THE
EASTERN NOAM TROUGH ALLOWING FOR PRECIPITATION CHANCES /BOTH WITH
COLD FRONTAL PASSAGE AS WELL AS SUBSEQUENT LAKE EFFECT
PRECIPITATION/.

MODEL AGREEMENT/CONFIDENCE: STRONG CONFIDENCE THROUGH NEXT TUESDAY
WITH ABOVE-AVERAGE CONFIDENCE THROUGH THE END OF THE FORECAST PERIOD
THURSDAY.  PRIMARY DIFFERENCE CONTINUES TO BE WITH THE MOVEMENT OF
THE EASTERN TROUGH...WITH THE ECMWF CONTINUING TO BE MUCH SLOWER
THAN THE GFS...WITH THE GEFS PROVIDING SUPPORT FOR THE SLOWER
ECMWF.  DIFFERENCES CONTINUE TO BE SMALL ENOUGH TO SUPPORT A
CONSENSUS APPROACH...WHICH WILL BE FOLLOWED FOR THIS PACKAGE.

MIDDLE RANGE /FRIDAY THROUGH SUNDAY/:

LITTLE HOPE FOR THOSE SEEKING SOME DRY WEATHER AS INITIAL CUTOFF
LOW CURRENTLY OVER THE EASTERN GREAT LAKES WILL LIFT NORTH JUST IN
TIME TO ALLOW IMPRESSIVE COMPACT SHORTWAVE NOW OVER THE DAKOTAS TO
DROP INTO THE WESTERN GREAT LAKES EARLY FRIDAY...PASSING OVERHEAD BY
FRIDAY EVENING.  QG SUPPORT FOR ASCENT IS STRONG WITH A QUICK BURST
OF WARM ADVECTION EARLY BEING REPLACED BY ROBUST COLD ADVECTION
ALONG/BEHIND A POTENT COLD FRONT THAT PUSHES THROUGH THE REGION
DURING THE LATE AFTERNOON/EVENING.  SEE LITTLE ROOM FOR DRY
WEATHER...AS THERE WILL BE SUBSTANTIAL MOISTURE IN THE DEVELOPING
MORNING WARM SECTOR /PWATS 0.75"/ FOR THE AFOREMENTIONED QG FORCING
TO WORK WITH AND PRODUCE SCATTERED/NUMEROUS SHOWERS THAT SHOULD BE
FOCUSED IN NICE LLEVEL CONVERGENCE MAX OVER THE TIP OF THE MITT
BETWEEN WARM SECTOR AND STRENGTHENING/ARRIVING COLD FRONT FROM THE
NORTH.  BY AFTERNOON...THE COLD FRONT WILL ADVANCE SOUTH AND EAST
WITH STRENGTHENING COLD ADVECTION AND DEEP MOISTURE ALLOWING THE
LAKES TO GET INVOLVED.  AHEAD OF THIS COLD FRONT...SHRA ACTIVITY
WILL EXPAND THROUGHOUT NORTHEAST LOWER.  ALL OF THIS SPELLS
WIDESPREAD SHRA ACTIVITY AS WE MOVE THROUGH THE EVENING AS
TEMPERATURES QUICKLY FALL BACK THROUGH THE 40S /AFTER A MILD START/
UNDER DEVELOPING COLD ADVECTION.

GOOD MOISTURE...T8S FALLING BELOW ZERO AND GENERALLY NEUTRAL SUPPORT
FOR ASCENT/DESCENT ALOFT SUGGESTS A GOOD NIGHT OF LAKE EFFECT
ACTIVITY AS SURFACE HIGH WELL NORTH OF THE GREAT LAKES REGION SLOWLY
BLEEDS SOUTH TOWARDS THE AREA.  FLOW IS GENERALLY 340 DEGREES IN THE
MIXED LAYER...WITH INVERSION HEIGHTS BELOW 5KFT. DESPITE THESE
SHALLOW INVERSION HEIGHTS...AS SUGGESTED BY THE PREVIOUS
FORECASTER...DEEP MOISTURE AND GOOD LLEVEL CYCLONIC FLOW WILL REALLY
MAKE THIS MORE OF A LAKE ENHANCED SETUP WITH WIDESPREAD SHOWER
ACTIVITY EXPECTED THROUGH THE NIGHT.  WET BULB ZERO HEIGHTS FALL TO
AROUND 2KFT BY DAYBREAK SATURDAY...WHICH WOULD ALLOW FOR SOME MIX
WITH SNOW OVER THE HIGH TERRAIN AND WILL INCLUDE THIS POSSIBILITY IN
THE FORECAST AFTER MIDNIGHT AS LOWS FALL THROUGH THE 30S.

SUBSTANTIAL DRYING ALOFT ARRIVES SATURDAY AS SURFACE RIDGE AXIS
BUILDS INTO THE WESTERN LAKES.  AS IS TYPICAL FOR LAKE EFFECT...THE
LLEVEL RESPONSE WILL HOLD ON LONGER THAN THIS INITIAL DRYING
ALOFT...SO EXPECT SHRA ACTIVITY TO CONTINUE THROUGH THE
MORNING...WITH ACTIVITY WANING DURING THE DAY AS MOISTURE THINS.
CLOUDS...ON THE OTHER HAND...WILL BE MUCH HARDER TO ELIMINATE...WITH
SKIES LIKELY TO REMAIN MOSTLY CLOUDY THROUGH EVENING. HIGHS WILL NOT
BE GOING MUCH OF ANYWHERE GIVEN T9S BELOW 0C...WITH INHERITED LOWER
40S LOOKING VERY GOOD...DESPITE BEING ON THE LOW END OF THE GUIDANCE
ENVELOPE.  THESE CLOUDS WILL LIKELY HOLD ON TO SOME EXTENT INTO
SATURDAY NIGHT...REDUCING CONFIDENCE IN THE OVERNIGHT LOW
TEMPERATURE FORECAST.  TEMPS IN THE MID 20S ARE CERTAINLY PLAUSIBLE
WITH ENOUGH CLEARING...BUT WILL CONTINUE TO GO A BIT WARMER THAN
THIS GIVEN AT LEAST SOME EXPECTED CLOUD COVER.

THE WEEKEND WILL END QUIETLY WITH A RIDGE OF HIGH PRESSURE BRIEFLY
BUILDING INTO NORTHERN MICHIGAN ON SUNDAY WITH THE LLEVEL FLOW
BACKING WESTERLY AND EVEN SOUTHWESTERLY BY AFTERNOON.  WITH T9S
REBOUNDING A FEW DEGREES...EXPECT HIGHS TO REACH THE MID/UPPER
40S...WHICH...DESPITE REMAINING WELL BELOW NORMAL...WILL FEEL WARMER
GIVEN WHAT SHOULD BE AMPLE SUNSHINE AND LIGHTER WINDS.

LONG RANGE /MONDAY THROUGH THURSDAY/:

SUNDAY NIGHT-MONDAY:  NICE SLUG OF QG FORCING ASSOCIATED WITH
ARRIVING NORTHERN STREAM SHORTWAVE WILL ALLOW FOR A BAND OF SHOWERS
AS THIS FORCING BECOMES COLLOCATED WITH LLEVEL WARM ADVECTION AND
LFQ JET DYNAMICS.  HAVE NO QUALMS WITH INHERITED LIKELY POPS AND
DEPENDING ON SYSTEM TIMING...COULD SEE MONDAY TURN OUT QUITE CHILLY
/HIGHS IN THE 40S CWA-WIDE?/ WITH CHILLY NORTHWEST WINDS DEVELOPING
TOWARDS EVENING. CYCLONIC FLOW CONTINUES THROUGH MONDAY NIGHT...WITH
AMPLE RESIDUAL MOISTURE ALLOWING LOW CLOUDS /AND POTENTIALLY SOME
FOG-DRIZZLE/.  NORTHEASTERLY FLOW CONFIGURATION AND PRETTY MARGINAL
TEMPERATURES ALOFT SUGGEST LITTLE LAKE-INDUCED PRECIPITATION...BUT
WILL LIKELY HELP ENTRENCH THE CLOUDS AND POTENTIAL DRIZZLE MENTIONED
ABOVE.

WOULD NOT BE SURPRISED IF THE LOW CLOUDS HANG AROUND INTO TUESDAY
BEFORE GRADUAL IMPROVEMENT AS HIGH PRESSURE BUILDS IN FROM THE
NORTH.  T9S 2-4C SUGGEST HIGHS AS HIGH AS 50...BUT WITH
AFOREMENTIONED CLOUD CONCERNS...WILL CONTINUE WITH VALUES A LITTLE
COOLER THAN THIS...GENERALLY IN THE UPPER 40S.  QUIET NIGHT TUESDAY
NIGHT WITH HIGH PRESSURE CENTERED JUST NORTHEAST OF THE GREAT LAKES.
CONTINUED RESIDUAL CLOUDS MAY IMPACT TEMPERATURES TUESDAY
NIGHT...BUT WITH THE CHILLY START...COULD CERTAINLY MAKE A RUN AT
THE LOWER 30S GIVEN ENOUGH CLEARING.

VERY QUIET TO END THE FORECAST PERIOD WEDNESDAY-THURSDAY WITH HIGH
PRESSURE ANCHORED NEAR OR JUST EAST OF THE GREAT LAKES REGION.
AFOREMENTIONED TIMING DIFFERENCES ON THE EASTWARD MOVEMENT OF THE
EASTERN NOAM TROUGH WOULD YIELD DIFFERENCES IN TEMPERATURES AT THIS
RANGE...BUT A RETURN TO CLIMATOLOGICAL HIGH TEMPS /HIGHS IN THE 50S/
AND DRY CONDITIONS ALSO YIELDING CHILLY NIGHTS NEAR FREEZING.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 713 PM EDT THU OCT 16 2014

MAINLY IFR CONDITIONS ARE EXPECTED TONIGHT INTO EARLY FRIDAY AS
CIGS CONTINUE TO LOWER AS AREAS OF FOG DEVELOP THANKS TO AMPLE LOW
LEVEL MOISTURE. A FEW SHOWERS ARE ALSO POSSIBLE TONIGHT INTO EARLY
FRIDAY...BUT WIDESPREAD RAIN SHOWERS WILL DEVELOP ON FRIDAY AS A
STRONG SHORT WAVE SWINGS THRU MICHIGAN. CIGS AND VSBYS WILL
IMPROVE SLIGHTLY TO LOW MVFR AS THESE SHOWERS DEVELOP. LIGHT/CALM
WINDS TONIGHT WILL BECOME SW BY MID TO LATE FRIDAY MORNING...AND
WILL THEN SHIFT TO THE NW AND INCREASE TO 15 TO 25 KTS LATE FRIDAY
AFTERNOON BEHIND THE SURFACE REFLECTION OF THE SHORT WAVE.

&&

.MARINE...
ISSUED AT 415 PM EDT THU OCT 16 2014

OVERALL LIGHT WINDS WILL PERSIST ON THE LAKES TONIGHT INTO FRIDAY.
BUT BIG CHANGES TAKE SHAPE FRIDAY NIGHT INTO SATURDAY AS ANOTHER
DEEP TROUGH AND SFC LOW PRESSURE SWINGS THROUGH THE NRN LAKES
REGION. BEHIND THE SFC LOW...GUSTY NW WINDS DEVELOP FRIDAY NIGHT
AND PERSIST THROUGH SATURDAY WITH GALE FORCE WIND GUSTS A GOOD
POSSIBILITY OVER MOST OF THE NRN MICHIGAN NEARSHORE AREAS.
THUS...GALE WATCH WILL BE ISSUED WITH THIS AFTERNOONS FORECAST.
WINDS DIMINISH LATE SATURDAY NIGHT INTO SUNDAY.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...GALE WATCH FROM FRIDAY EVENING THROUGH SATURDAY EVENING FOR
     LHZ347>349.
LM...GALE WATCH FROM FRIDAY EVENING THROUGH SATURDAY EVENING FOR
     LMZ323-342-344>346.
LS...GALE WATCH FROM FRIDAY EVENING THROUGH SATURDAY EVENING FOR
     LSZ321.

&&

$$

SYNOPSIS...TL
SHORT TERM...ADAM
LONG TERM...ARNOTT
AVIATION...MR
MARINE...ADAM






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