Area Forecast Discussion
Issued by NWS Gaylord, MI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KAPX 201759
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1259 PM EST THU NOV 20 2014

.SYNOPSIS...
ISSUED AT 339 AM EST THU NOV 20 2014

LAKE EFFECT SNOW...AT TIMES HEAVY...WILL CONTINUE IN THE TRADITIONAL
SNOW BELT AREAS TODAY. HIGH PRESSURE BRINGS A GRADUAL END TO LAKE
SNOWS TONIGHT...AND ESPECIALLY ON FRIDAY. MILDER WEATHER ARRIVES FOR
THIS WEEKEND INTO THE START OF NEXT WEEK...ALONG WITH PERIODS OF
RAIN.

&&

.UPDATE...
ISSUED AT 1045 AM EST THU NOV 20 2014

OVERVIEW: DEEP TROUGHING/COLD AIR SPANS FROM HUDSON BAY DOWN THROUGH
THE GREAT LAKES AND OHIO VALLEY. NEEDLESS TO SAY...ANOMALOUSLY COLD
AIR WITH A POCKET OF -20C OR COLDER H8 AIR AND A WHOPPING POCKET OF
-40C H5 AIR OR COLDER ROTATING THROUGH THE NRN GREAT LAKES THIS
MORNING. THUS...STEEP LOW-MID LEVEL LAPSE RATES/NO INVERSION TO
SPEAK OF AND RESULTING TREMENDOUS LAKE INDUCED INSTABILITY HAS
BROUGHT ABOUT INTENSE LAKE EFFECT SNOW BANDS OVER THE LAST 18 HOURS
WITH SNOWFALL RATES RUNNING 1 TO 2 INCHES PER HOUR.

STACKED LOW PRESSURE SYSTEM RESIDES NORTHEAST OF THE REGION ALONG
THE ONTARIO/QUEBEC BORDER. REGIONAL MESO-ANALYSIS REVEALING AN AXIS
OF VERY STRONG CONVERGENCE WITHIN A BROADER LOW LEVEL SFC TROUGH
SITTING ACROSS EASTERN LAKE SUPERIOR WITH A COUPLE OF INTENSE LAKE
BANDS CONVERGING RIGHT INTO NRN CHIPPEWA COUNTY (INCLUDING THE
SOO)...ALTHOUGH THOSE BANDS ARE GETTING SHOVED SOUTHWARD A BIT.
SECOND POCKET OF CONVERGENCE NOTED OVER NRN LAKE MICHIGAN WHERE THE
STRONGEST LAKE EFFECT BANDS HAVE/ARE LOCATED...AIDED BY A LONGER
FETCH ACROSS LAKE MICHIGAN AND CONNECTIONS BACK TO GREEN BAY. THESE
BANDS HAVE ALSO BEEN PUSHED SOUTHWARD JUST A BIT OVER THE LAST
COUPLE OF HOURS HELPING TO SPREAD THE SNOW AMOUNTS OUT...SOME.

THUS FAR...HIGHEST SNOW AMOUNTS HAVE OCCURRED ACROSS ANTRIM AND
OTSEGO COUNTIES AND A PORTION OF KALKASKA AND CRAWFORD
COUNTIES...WHERE SOMEWHERE ON THE ORDER OF 8 TO 15 INCHES HAVE
FALLEN PER SPOTTER REPORTS AND RADAR SNOWFALL ESTIMATES. LESSER
AMOUNTS ACROSS CHIPPEWA COUNTY BUT ONLY BECAUSE SNOW BANDS HAVE BEEN
MORE TRANSIENT.

REST OF TODAY INTO TONIGHT...A SLOW IMPROVEMENT. STACKED LOW SLOWLY
MOVES OFF TO THE EAST TODAY BEFORE STRONG HIGH PRESSURE/SUBSIDENCE
AND DRIER AIR BUILDS INTO THE REGION TONIGHT. BUT WE STILL HAVE
SEVERAL MORE HOURS OF DECENT LAKE EFFECT TO GET THROUGH THIS
AFTERNOON INTO THIS EVENING BEFORE MARKED IMPROVEMENT OCCURS. LOW
LEVEL MEAN FLOW EXPECTED TO SLOWLY VEER MORE NORTHWESTERLY IN TIME
WHICH WILL KEEP THE OVERALL FOCUS OF THE HEAVIER SNOW SHOWERS OVER
THE TRADITIONAL SNOW BELT AREAS. WITHIN THOSE SNOW BELTS...SEVERAL
MORE HOURS OF 1 TO 2 INCH/HOUR SNOWS SUGGESTS ANOTHER 7 TO 14
INCHES. BUT TYPICALLY...LES BANDS NOT LIKELY TO REMAIN FIXED OVER
ANY PARTICULAR SPOT AND 7 INCHES (ADDITIONAL) IS PROBABLY A TOP
END.

HEADLINES...NOT PLANNING MUCH OF A CHANGE WITH THE LATE MORNING
UPDATE AS MOST OF THE WARNINGS CURRENTLY IN PLACE HAVE VERIFIED AND
ARE CERTAINLY WARRANTED. MAY NEED TO ADD KALKASKA COUNTY INTO THE
MIX AS WINDS VEER MORE NW...AND LEELANAU IS ALWAYS A WILD CARD. NOT
SO SURE ABOUT WARNINGS IN EMMET AND CHEBOYGAN COUNTIES WHERE LESS
SNOW HAS FALLEN AND FOCUS WILL TEND TO MOVE OUT OF THOSE LOCATIONS
TODAY. BUT WILL LEAVE THEM ALONE FOR NOW...AND RE-ASSESS FOR THE
AFTERNOON FORECAST PACKAGE.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 339 AM EST THU NOV 20 2014

...HEAVY LAKE EFFECT SNOW CONTINUES...

HIGH IMPACT WEATHER POTENTIAL: SIGNIFICANT LAKE EFFECT SNOW EVENT
WITH EXTREMELY DIFFICULT TRAVEL IN WEST-NORTHWEST FLOW FAVORED
AREAS.

PATTERN SYNOPSIS/FORECAST:  UPPER LOW NORTH OF LAKE SUPERIOR WITH
DEEP TROUGH AND CYCLONIC FLOW ACROSS THE GREAT LAKES.  SEVERAL
EMBEDDED SHORTWAVE FEATURES WITHIN THE TROUGH ROTATING ACROSS
MICHIGAN.  DEEP MOISTURE AND ABUNDANT OVERLAKE INSTABILITY RESULTING
IN IMPRESSIVE LAKE EFFECT SNOW DOWNWIND OF LAKES MICHIGAN AND
SUPERIOR.  LONGWAVE TROUGH WILL GRADUALLY SHIFT EAST THROUGH TONIGHT
WITH FLOW BECOMING WEAKLY ANTICYCLONIC BY FRIDAY MORNING HELPING TO
DIMINISH THE LAKE EFFECT SNOW MACHINE.

HISTORIC WEEK OF LAKE EFFECT SNOW FOR NORTHERN MICHIGAN AND ONE THAT
WE WILL LIKELY TALK ABOUT FOR YEARS TO COME.  JUST LOOKING AT
GAYLORD... RECORDS HAVE BEEN SET FOR DEEPEST NOVEMBER SNOWDEPTH /20
INCHES/...MOST SNOW EVER IN A 5 DAY PERIOD /30+ INCHES/ AND POSSIBLY
THE SNOWIEST NOVEMBER ON RECORD.  FOR TODAY...MUCH OF THE SAME WITH
INTENSE WEST-NORTHWEST FLOW LAKE EFFECT.  SOME HINTS ON SATELLITE OF
SOME DRIER AIR MOVING ACROSS GREEN BAY/LAKE MICHIGAN POSSIBLY TIED
TO AN AREA OF WEAK SUBSIDENCE BEHIND A SHORTWAVE TROF.  THIS HAS HAD
SOME EFFECT AT WEAKENING/DISRUPTING THE MOST INTENSE SNOW
BANDS...BUT STILL SEEING A FEW DOMINATE BANDED STRUCTURES TIED
DIRECTLY TO NORTHERN GREEN BAY EXTENDING INTO NORTHERN CRAWFORD
COUNTY AND OTSEGO COUNTY. OVER EASTERN UPPER...IMPRESSIVE BAND OF
SNOW COMING RIGHT THROUGH WHITEFISH BAY INTO SAULT STE. MARIE.
AREAS NORTH OF M-28 IN CHIPPEWA COUNTY WILL CONTINUE TO BE HIT
HARD THROUGHOUT THE DAY. THE DRIER AIR AND WEAKENED BANDS WILL BE
SHORT-LIVED AS FORECAST SOUNDINGS ARE QUITE IMPRESSIVE TODAY WITH
STRONG OMEGA PEGGED RIGHT THROUGH THE DGZ...WITH DEEP MOISTURE UP
THROUGH 600MB. EVEN OUTSIDE OF THE DOMINATE BANDS...MULTIPLE LAKE
EFFECT BANDS WILL CREATE SEVERAL INCHES OF SNOW AND AREAS OF POOR
VISIBILITY/SNOW COVERED ROADS.

LOW LEVEL WINDS VEER SLIGHTLY MORE WEST-NORTHWEST THIS AFTERNOON
WHICH MAY HELP TO DISRUPT/WEAKEN THE GREEN BAY CONNECTION AND SPREAD
OUT THE LAKE EFFECT BANDS.  THE REMAINDER OF THE AREA WILL FORECAST
SOUNDINGS ALSO SHOW A GRADUAL DECREASE IN THE STRONGEST OMEGA
THROUGH THE DGZ.  WITH THAT SAID...SEE LITTLE REASON WHY PARTS OF
THE WARNING AREA /GENERALLY FROM WESTERN ANTRIM TO OTSEGO TO
NORTHERN CRAWFORD COUNTY/ WILL NOT SEE AN ADDITIONAL 6-10 INCHES OF
SNOW TODAY.  THIS COULD EASILY BRING 24 HOUR SNOWFALL TOTALS TO 1-2
FEET IN SOME AREAS.  WINDS REMAIN GUSTY WITH WIDESPREAD BLOWING SNOW
AND EXTREMELY DIFFICULT TRAVEL.

SLOW BUT STEADY IMPROVEMENT TONIGHT WITH FLOW ALOFT TURNING MORE
ANTICYCLONIC AND INVERSIONS LOWERING TOWARD 800MMB.  LAKE EFFECT
SNOW STILL ONGOING BUT MUCH LESS INTENSE WITH DECREASING MOISTURE
PROFILES.

HEADLINES:  ALL CURRENT HEADLINES WILL REMAIN.  GIVEN HOW FAR SOME
OF THE STRONGER BANDS HAVE PUSHED INLAND...WILL ADD OSCODA COUNTY TO
THE ADVISORY.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 339 AM EST THU NOV 20 2014

...A RETURN TO SOMETHING RESEMBLING NORMAL...FINALLY...

HIGH IMPACT WEATHER POTENTIAL: POSSIBLE LIGHT FREEZING RAIN EVENT
SATURDAY MORNING.

PATTERN SYNOPSIS/CURRENT CONDITIONS:

PRIMARY FORECAST CONCERNS/CHALLENGES: SIGNIFICANT CHANGES JUST
AROUND THE CORNER...WITH A DECISIVE FLOOD OF MUCH MILDER PACIFIC
ORIGINATED AIR INTO THE AREA THIS WEEKEND INTO THE START OF NEXT
WEEK. DRIVER BEHIND SUCH AGGRESSIVE CHANGES IS COMPLETE BREAKDOWN OF
CURRENTLY ANOMALOUSLY AMPLIFIED PATTERN AS EXTENDED AND STRONG
PACIFIC UPPER JET SLAMS ACROSS THE WEST COAST LATER THIS WEEK.
ASSOCIATED DEVELOPMENT OF WESTERN TROUGH...MOISTURE RICH SOUTHERLY
FLOW OUT AHEAD OF IT...AND INTERACTION BETWEEN NORTHERN AND SOUTHERN
SHORTWAVES LOOKS TO DRUM UP A POTENTIALLY STRONG STORM SYSTEM BY
LATER THIS WEEKEND INTO MONDAY. GOOD NEWS FOR THE SNOW
WEARY...HOWEVER...WITH A NEARLY A COMPLETE LACK OF ANY COLD AIR BY
THAT TIME...SUGGESTING MUCH OF THE PRECIPITATION FALLING AS RAIN
(PERHAPS A TOUCH OF FREEZING RAIN AT THE ONSET). ANOTHER SURGE OF
COLD AIR TO FOLLOW THIS SYSTEM INTO MID-WEEK...BUT CURRENT
INDICATIONS IT WILL BE NOT NEARLY AS COLD AS THIS RECENT NOW MULTI-
DAY RECORD SETTING COLD SPELL.

PRIMARY FORECAST CHALLENGES/CONCERNS: MAIN EMPHASIS ON TEMPERATURE
TRENDS AND POTENTIAL FOR A TOUCH OF FREEZING RAIN EARLY SATURDAY.

DETAILS: THE BEGINNING TO THE END OF THIS FRIGID PATTERN BEGINS AS
QUICKLY AS FRIDAY WITH RAPID HEIGHT RISES AS LONG WAVE PATTERN
QUICKLY TRANSITIONS TO ONE OF A MUCH MORE ZONAL FLAVOR. WHILE
WARMING ALOFT IS ACTUALLY QUITE AGGRESSIVE...PER THE USUAL...SUCH
WARMING WILL NOT BE REALIZED AS QUICKLY AT THE SURFACE...WITH HIGHS
STUCK MOSTLY IN THE MID 20S (DEEP SNOWPACK FOR SOME AREAS ONLY
HELPING THE COOLING CAUSE). OTHER THAN A FEW LINGERING LIGHT SNOW
SHOWERS DURING THE MORNING...A RATHER UNEVENTFUL DAY WITH EVEN SOME
PEEKS OF SUNSHINE EXPECTED. WEAK WAVE AND INITIAL STAGES OF MOIST
ADVECTION SPREAD ACROSS THE AREA LATE FRIDAY NIGHT INTO SATURDAY.
DYNAMICS ANYTHING BUT IMPRESSIVE...AND MOISTURE THROUGH THE COLUMN
REMAINS DISJOINTED. GUIDANCE CONTINUES TO SPIT OUT SOME VERY LIGHT
PRECIPITATION. HARD TO ARGUE WITH SUCH...BUT WILL KEEP POPS LOW
GIVEN ABOVE. AS FOR PRECIP TYPE...THAT IS A TOUCH OF A CHALLENGE AS
OFF THE DECK SURFACE TEMPERATURES WARM TO ABOVE FREEZING LEVELS
RATHER AGGRESSIVELY AS PRECIPITATION ARRIVES. DEFINITELY SOME ROOM
FOR EVAP COOLING OVERNIGHT FRIDAY...PERHAPS ALLOWING MAINLY LIGHT
SNOW INITIALLY TO REACH THE SURFACE. WARM ADVECTION AND LOWER LEVEL
SATURATION EXPECTED TO LEAD TO FULL MELTING SATURDAY MORNING. AND
THERE LIES THE CONCERN...WITH SKIN TEMPERATURES EXPECTED TO REMAIN
SEVERAL DEGREES BELOW FREEZING. NOT LOOKING LIKE A SIGNIFICANT
EVENT...BUT DEFINITELY COULD SEE SOME LIGHT FREEZING RAIN/DRIZZLE
SATURDAY MORNING THAT MAY LEAD TO SOME HAZARDOUS DRIVING CONDITIONS.
MAINLY JUST RAIN EXPECTED FOR THE AFTERNOON AS SURFACE TEMPS RISE TO
JUST ABOVE FREEZING.

AFTER WAFFLING BACK AND FORTH FOR THE LAST SEVERAL CYCLES...GUIDANCE
HAS COME INTO MUCH BETTER AGREEMENT DEVELOPING SIGNIFICANT LOW
PRESSURE ACROSS THE MID MISSISSIPPI VALLEY REGION SUNDAY
MORNING...STRENGTHENING IT TO SUB 980MB LEVELS AS IT MOVES NNE TO
VICINITY WISCONSIN/NORTHERN LAKE MICHIGAN MONDAY MORNING. AREA WILL
SQUARELY BE IN THE WARM SECTOR...WITH H8 TEMPERATURES SEVERAL
DEGREES ABOVE ZERO. RAIN WILL BE THE PRECIP TYPE SUNDAY INTO THE
START OF MONDAY...OF WHICH THERE COULD BE A DECENT AMOUNT LATE
SUNDAY THROUGH SUNDAY NIGHT GIVEN DEEP LAYER JET DYNAMICS AND PWAT
VALUES SURGING TO JUST SHY OF ONE INCH VALUES. NOT ESPECIALLY
CONSIDERED ABOUT ANY FLOODING ISSUES WITH RAIN TOTALS LIKELY TO
REMAIN SUB ONE INCH AND RATHER LIMITED WATER CONTENT EVEN IN THE
DEEPEST SNOW PACK AREAS.

COLD FRONT PLOWS ACROSS THE AREA MONDAY...ACCOMPANIED BY SOME GUSTY
WINDS AND FALLING TEMPERATURES. LINGERING SHOWERS WILL TURN OVER TO
SNOW...WITH SOME LAKE ENHANCED SNOWS EXPECTED MONDAY NIGHT INTO
TUESDAY WITH LINGERING MOISTURE AND H8 TEMPERATURES DROPPING ONCE
AGAIN TO SUB -10C LEVELS. PLENTY OF QUESTION MARKS HEADING INTO THE
REMAINDER OF THE WEEK...WITH MID RANGE GUIDANCE VARYING
SIGNIFICANTLY. SHOULD BE A CHILLY PERIOD...BUT NOT NEARLY AS COLD AS
THIS CURRENT PATTERN. CONCERNS WITH ADDITIONAL LAKE SNOWS/PASSING
WAVES ARGUES FOR AT LEAST SOME SNOW CHANCES THROUGH THURSDAY.

TEMPERATURES...BY RECENT STANDARDS...A "WARM" WEEKEND INTO THE START
OF NEXT WEEK...WITH MID/UPPER 30 HIGHS SATURDAY REACHING INTO THE
LOWER AND MIDDLE 40S SUNDAY INTO THE START OF MONDAY. HARD TO
BELIEVE...BUT NORMAL HIGHS THIS TIME OF YEAR ARE STILL IN THE UPPER
30S AND LOWER 40S. AS MENTIONED...COOLER TUESDAY THROUGH
THURSDAY...WITH HIGHS BACK DOWN INTO THE 20S AND 30S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1259 PM EST THU NOV 20 2014

HEAVY LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO IMPACT NW LOWER
MICHIGAN THROUGH THE AFTERNOON...RESULTING IN LOW MVFR TO IFR
CONDITIONS AT TVC/MBL AT TIMES. PLN MAY CATCH A BREAK FOR A WHILE AS
HEAVIEST SNOW SHOWERS HAVE SHIFTED A BIT FURTHER SOUTH...BUT
ANOTHER BATCH OF HEAVIER SNOWS MAY SHIFT OUT OF EASTERN UPPER AND
DOWN INTO THE TIP OF THE MITT OVER THE NEXT FEW HOURS.

SNOW SHOWERS WILL WIND THEMSELVES DOWN TONIGHT AS HIGH PRESSURE
AND DRIER AIR BUILD ACROSS THE REGION. TVC/MBL/PLN WILL LIKELY
CONTINUE TO SEE SNOW SHOWERS...BUT FLIGHT CONDITIONS WILL LARGELY
REMAIN MVFR OR BETTER. APN GETS OUT OF THE SNOW SHOWERS TONIGHT
WITH VFR CONDITIONS ANTICIPATED THERE.

WINDS...GUSTY FROM THE W/WNW THROUGH THE AFTERNOON WITH A GRADUAL
VEERING TOWARD NW (310 DEGREES) BY EVENING. GUSTINESS ENDS THIS
EVENING.

&&

.MARINE...
ISSUED AT 339 AM EST THU NOV 20 2014

GALE FORCE GUSTS EXPECTED ON PORTIONS OF LAKE MICHIGAN
THIS MORNING AND ACROSS NORTHERN LAKE HURON INTO TONIGHT...WITH
SMALL CRAFT ADVISORIES ELSEWHERE. WEST/NORTHWEST FLOW LAKE EFFECT
SNOW WILL CONTINUE THROUGHOUT TODAY...RESULTING IN AREAS OF REDUCED
VISIBILITIES ALONG THE COASTLINE.  ANOTHER STORM SYSTEM WILL MOVE
INTO THE GREAT LAKES FRIDAY NIGHT INTO THIS WEEKEND BRINGING WARMER
TEMPERATURES BUT ALSO ADDITIONAL MARINE HEADLINES AS THE GRADIENT
TIGHTENS.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR MIZ018-
     020-025>027-029-031-032.

     LAKE EFFECT SNOW WARNING UNTIL 5 AM EST FRIDAY FOR MIZ008-016-
     017-019-021>023-028.

LH...SMALL CRAFT ADVISORY UNTIL 5 AM EST FRIDAY FOR LHZ345-346-349.

     GALE WARNING UNTIL 11 PM EST THIS EVENING FOR LHZ347-348.

LM...SMALL CRAFT ADVISORY UNTIL 5 AM EST FRIDAY FOR LMZ323-341-342-
     344>346.

LS...SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR LSZ321-
     322.

&&

$$

UPDATE...ADAM
SYNOPSIS...MSB
SHORT TERM...KEYSOR
LONG TERM...MSB
AVIATION...ADAM
MARINE...KEYSOR


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.