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000
FXUS63 KAPX 171105
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
705 AM EDT MON MAR 17 2014

.SYNOPSIS...
ISSUED AT 315 AM EDT MON MAR 17 2014

ARCTIC HIGH PRESSURE OVER NORTHERN MICHIGAN WILL BEGIN TO PULL EAST
OF THE REGION TODAY...WITH SOME INCREASING UPPER LEVEL CLOUDINESS
EXPECTED...ALONG WITH SOMEWHAT MILDER TEMPERATURES.  LOW PRESSURE
WILL ORGANIZE OVER THE CENTRAL PLAINS ON TUESDAY...AND MOVE INTO THE
GREAT LAKES REGION ON TUESDAY NIGHT AND WEDNESDAY... BRINGING A
WINTRY MIX OF PRECIPITATION TO THE AREA.  HIGH PRESSURE WILL
GRADUALLY BUILD BACK INTO THE REGION ON THURSDAY...WITH TEMPERATURES
REMAINING BELOW SEASONAL NORMS.

&&

.UPDATE...
ISSUED AT 658 AM EDT MON MAR 17 2014

HIGH CLOUDS CONTINUE TO STREAM IN OVERHEAD...WITH THICKER MID
CLOUD SET TO ARRIVE LATER THIS MORNING AND THIS AFTERNOON. NO
CHANGES TO FORECAST...TEMPS DID NOT GET AS COLD AS PREVIOUSLY
THOUGHT...BUT THE DAY STARTS OUT WITH SINGLE DIGITS ABOVE AND
BELOW ZERO READINGS.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 315 AM EDT MON MAR 17 2014

...COLD START WITH A QUICK REBOUND AND SMALL CHANCE FOR LIGHT SNOW
NORTH AND WEST TONIGHT...

IMPACTS: NONE.

CONFIDENCE: FAIRLY LOW ON SNOW DEVELOPMENT AND MINOR ACCUMULATION
POTENTIAL IN EASTERN UPPER TONIGHT.

CURRENT WEATHER AND SYNOPTIC PATTERN/EVOLUTION:

COLD OUTSIDE WITH CALM WINDS...DRY AIR AND ONLY SOME HIGH LEVEL THIN
CIRRUS. TEMPERATURES HAVE TUMBLED INTO THE TEENS AND LOWER 20S BELOW
ZERO IN THE LOWER LYING AREAS NORTH...AND MAINLY SINGLE DIGITS BELOW
ZERO ELSEWHERE...WITH JUST SOME SPORADIC LOCALES SLIGHTLY ABOVE
ZERO...WHERE THERE IS A BREATH OF WIND...SUCH AS WHERE LAND BREEZES
RESIDE. THE PATTERN SHOWS SFC HIGH PRESSURE JUST EAST OF US...WITH A
WEAK SOUTHERLY RETURN FLOW TRYING TO DEVELOP. THE UPPER LEVEL FLOW
IN WNW AND RATHER BRISK...WITH A NOTICEABLE LITTLE WAVE...ALBEIT
WEAKENING/SHEARING OUT...OVER THE ARROWHEAD OF MN. THIS WAVE WAS
WORKING WITH BETTER DYNAMICS AND LOW LEVEL WAA/H8 JETLET 50KT+
EARLIER...BUT THINGS ARE WEAKENING FAST. THIS WAVE...COMBINED WITH
OTHER VERY WEAK VORTICITY IS STREAMING OUR WAY...AND TRYING TO
MOISTEN UP THE MID AND UPPER LEVELS. CONSIDERING OUR 00Z APX
SOUNDING WAS 0.04" PWAT...THAT`S A TALL TASK. EVEN FURTHER
UPSTREAM...A MORE SIGNIFICANT SHORTWAVE PUSHING THROUGH THE WESTERN
CONUS WAS REALLY SQUASHING THE UPPER RIDGING THAT WAS WORKING
THROUGH THE ROCKIES. OBVIOUSLY...FORCING IS MUCH STRONGER WITH 100+
KT UPPER JET AND STRONG LOW LEVEL JET/WARM AND MOIST ADVECTION OF
THE PACIFIC...RESULTING IN WIDESPREAD PRECIPITATION. LOW PRESSURE
WITH THIS SHORTWAVE WAS DEVELOPING OVER MT...WITH A WARM FRONT
DEVELOPING ACROSS SD TOWARD IA. WEAK FGEN NOTED ALONG AND NORTH OF
THIS FEATURE WITH HIGH LEVEL PRECIPITATION...AND JUST SOME SPOTTY
FLURRIES AND SPRINKLES HITTING GROUND...AS CEILINGS WERE STILL QUITE
HIGH ABOVE 6-7KFT. THE WEAKENING ARROWHEAD WAVE WILL CONTINUE TO
WEAKEN AS IT CROSS NRN MICHIGAN TODAY...ALONG WITH THE OTHER EVEN
WEAKER EMBEDDED VORTICITY. THE STRONGER SHORTWAVE FROM THE WEST
COAST WILL LIFT THROUGH THE CENTRAL ROCKIES AND OUT INTO THE CENTRAL
PLAINS ALONG WITH DEEPENING LOW PRESSURE AROUND DAYBREAK TOMORROW.
THE WARM FRONT PIVOTS FROM THIS LOW UP THROUGH SRN MN/WI AND FAR SRN
LAKE MICHIGAN. FOR LATE TODAY AND TONIGHT...WE DO SEE MORE WARM AND
MOIST ADVECTION...MOSTLY ALOFT...BUT THE POTENTIAL FOR A BRIEF
PERIOD OR TWO OF WEAK FGEN IS THERE...ESPECIALLY IN THE NW CWA
FOCUSED IN EASTERN UPPER.

WEATHER EXPECTATIONS:

CIRRUS AND EVEN SOME MID CLOUD WILL THICKEN THROUGH THE DAY
RESULTING IN A MOSTLY CLOUDY SKY...WHILE LOW LEVEL WINDS TURN
SOUTHEAST AND ADVECT MILDER AIR BACK INTO THE REGION. THIS WILL
HELP VERY COLD DAYBREAK TEMPERATURES RISE INTO THE LOW TO MIDDLE
20S...UPPER 20S ACROSS DOWNSLOPING REGIMES OF NW LOWER. COULD SEE
SOME PERIODS OF LIGHT SNOW/FLURRIES ACROSS MAINLY THE NW HALF OF THE
CWA...ESPECIALLY EASTERN UPPER. MAYBE A FEW TENTHS OF AN INCH OF
SNOW THERE...BUT CERTAINLY INSIGNIFICANT. SKIES WILL BE MORE ON THE
CLOUDY SIDE ESPECIALLY LATER TODAY AND THIS EVENING. COULD SEE SOME
THINNER CLOUDS IN THE SRN CWA LATE TONIGHT. LOWS MAINLY IN THE TEENS
TO LOWER 20S IN THOSE SAME DOWNSLOPING REGIMES.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 AM EDT MON MAR 17 2014

...ACCUMULATING SNOW INCREASINGLY LIKELY EASTERN UPPER TUE-WED...

HIGH IMPACT WEATHER POTENTIAL: SOME FREEZING RAIN POTENTIAL NORTHERN
LOWER TUESDAY NIGHT/EARLY WED /PARTICULARLY ON BACK ROADS/...WITH
ACCUMULATING SNOW POSSIBLE NORTH OF THE BRIDGE.  ADDITIONAL CHANCE
FOR SNOW SOUTHERN AREAS ON FRIDAY.

PATTERN SUMMARY: OVERNIGHT ANALYSIS OF THE LONGWAVE PATTERN SUGGESTS
A THREE-WAVE PATTERN ACROSS THE NORTHERN HEMISPHERE WITH OUR WINTER
NEMESIS /A LONGWAVE TROUGH/ RIGHT WHERE WE/D EXPECT IT...OVER THE
EASTERN QUARTER OF NORTH AMERICA.  TO THE WEST OF THIS...THE PATTERN
IS SOMEWHAT DIFFERENT THAN WE HAVE SEEN FOR MUCH OF THE WINTER...
WITH WATER VAPOR IMAGERY REVEALING AN ONSLAUGHT OF PACIFIC
FLOW/MOISTURE AND RELATIVE WARMTH INVADING WESTERN NORTH AMERICA AS
RECENT EASTERN PACIFIC RIDGING FOLDS EAST AHEAD OF A MODEST LOW
PRESSURE SYSTEM THAT IS NOW EMERGING EAST OF THE CANADIAN ROCKIES.
THIS SYSTEM WILL EVENTUALLY TEAM UP WITH ADDITIONAL SHORTWAVE ENERGY
TO PROVIDE OUR WELL-ADVERTISED MID-WEEK WEATHER MAKER.  BEYOND
THIS...WE NEED TO LOOK FURTHER UPSTREAM WHERE DETERMINISTIC/ENSEMBLE
GUIDANCE IS IN RATHER GOOD AGREEMENT THAT RIDGING WILL AGAIN
DEVELOP/CLOSE OFF OVER ALASKA FORMING A BLOCKING PATTERN OVER THE
CENTRAL/EASTERN PACIFIC.  THIS WILL ALLOW FOR A GRADUAL RESURGENCE
OF THE NORTHERN STREAM...WITH TROUGHING OVER EASTERN NOAM TIGHTENING
IT/S GRIP TO END THE FORECAST PERIOD. AS THIS OCCURS...THE STORM
TRACK WILL GRADUALLY SINK SOUTH...BUT MAY REMAIN CLOSE ENOUGH FOR
ADDITIONAL PRECIPITATION CHANCES TO END THE WEEK.

IN SUMMARY...A POTENTIALLY ACTIVE WEATHER WEEK IS IN STORE WITH AT
LEAST 1 AND PERHAPS 2 PRECIPITATION CHANCES.  GIVEN THE ONSLAUGHT OF
PACIFIC AIR...WILL CERTAINLY HAVE PRECIPITATION TYPE ISSUES FOR THE
FIRST EVENT...WITH ANY LATE WEEK PRECIPITATION...IF IT OCCURS...TO
TAKE THE FORM OF SNOW WITH THE INCREASING INFLUENCE OF THE NORTHERN
STREAM.  TEMPERATURES WARM TO START THE PERIOD /TO NEAR CLIMO/...BUT
BACK TO AROUND 10F BELOW CLIMO TO END THE WEEK...AND LIKELY COLDER
THAN THIS FOR THIS COMING WEEKEND.

NOW FOR SOME DETAILS...

TUESDAY: DEVELOPING LOW PRESSURE OVER THE CENTRAL PLAINS BEGINS TO
MAKE PROGRESS INTO MID AN UPPER MISSISSIPPI VALLEY TOWARDS EVENING.
STRIP OF MID LEVEL MOISTURE LOOKS TO LAY ACROSS EASTERN UPPER TO
START THE DAY...WITH STRENGTHENING SOUTHERLY LLJ IMPINGING ON FRONT
AT H8 TO CONSOLIDATE A STRIP OF FGEN FORCING IN THIS LOCATION.
UNCERTAINTY TO WHETHER THIS CAN OVERCOME SOME INITIALLY DRY
AIR...BUT A CHANCE OF SN IS WARRANTED OVER EASTERN UPPER GIVEN THIS
SETUP.  FURTHER SOUTH...LLEVEL AIRMASS IS TOO DRY...AND WITH
SOUTHEASTERLY LLEVEL FLOW AND /INITIALLY/ DRY SOUTHERLIES AT
H8...SEE NO PRECIP CONCERNS OVER NORTHERN LOWER.  T9S SUPPORT 40 OR
A LITTLE WARMER OVER NORTHERN LOWER AND WILL CONTINUE THE TREND OF
PREVIOUS FORECASTS OF REMAINING ON THE WARMER END OF THE GUIDANCE
/FOLLOWING BEST PERFORMING T GUIDANCE OF LATE/. A GOOD BIT COOLER
OVER EASTERN UPPER WITH FLOW OFF OF ICY LAKE HURON/GEORGIAN BAY...AS
WELL AS COOLER TEMPS ALOFT AND ADDITIONAL CLOUD COVER.  LOWER 30S
LIKELY ALL WE/LL BE ABLE TO DO UP HERE.

TUESDAY NIGHT - WEDNESDAY:  REASONABLE...BUT NOT TERRIFIC AGREEMENT
ON THE PERIOD AS CENTRAL PLAINS LOW PRESSURE SYSTEM EJECTS NORTH AND
EAST INTO THE GREAT LAKES REGION.  MODEL TRENDS CONTINUE TO BE FOR A
SLIGHTLY WEAKER AND FURTHER EAST SOLUTION...WHICH IS MORE TOWARDS AN
ECMWF-LIKE SOLUTION.  THE GFS/SREF ARE ON THE NORTHERN END OF THE
ENVELOPE...WITH ALMOST ALL GEFS MEMBERS CLOSER TO THE ECMWF...WITH
THE GGEM ALSO IN THIS LATTER CAMP.  WILL TREND THE FORECAST TOWARDS
THIS WEAKER/COOLER SOLUTION...WHICH ALTERS PTYPE THINKING A TAD.
FIRST AND FOREMOST...PATTERN RECOGNITION DOES NOT SUPPORT A
SIGNIFICANT FREEZING RAIN EVENT GIVEN RAPIDLY RETREATING HIGH...WITH
THE BEST ICING LIKELY TIED TO COLD ROADWAY TEMPERATURES...ALTHOUGH
NOT AS BAD AS RECENTLY GIVEN A "MILD" DAY ON TUESDAY WITH MUCH
HIGHER SUN ANGLES THAN THE LAST TIME WE DEALT WITH THIS SCENARIO.
SECOND...GGEM/ECMWF TAKEN ALONE WOULD BRING NOTHING BUT SNOW FOR
MUCH OF CHIP/MACK...AND WITH A CONSENSUS LOW TRACK MORE THROUGH THE
CENTER OF THE CWA...THIS IS CERTAINLY PLAUSIBLE.  THEREFORE...WILL
ADJUST WORDING SLIGHTLY...REMOVING ZR MENTION FROM EASTERN
UPPER...AND LEAVING SNOW AS A POSSIBLE TYPE THROUGH THE EVENT. BY
THE SECOND HALF OF WEDNESDAY...CONFIDENCE IS HIGHER THAT ALL AREAS
TRANSITION BACK TO SNOW IN DEFORMATION/WRAP-AROUND MOISTURE.

QPF/SNOW: WITH SHORTWAVE GOING NEGATIVE TILT AS GULF MOISTURE TAP
ARRIVES...PRECIPITATION SHOULD EXPAND OVERHEAD QUITE RAPIDLY AFTER
MIDNIGHT TUESDAY NIGHT THROUGH EARLY WEDNESDAY.  FOR LOCATION SOUTH
AND EAST OF THE LOW TRACK /SOMEWHERE NEAR THE STRAITS/ SEE AMOUNTS
NOT GETTING TOO OUT OF HAND...WITH A 36 HR TOTAL THROUGH WEDNESDAY
NIGHT OF A FEW TENTHS.  TO THE NORTH AND WEST...WHERE PRECIPITATION
LASTS A LITTLE LONGER...COULD CERTAINLY ADD ANOTHER TENTH OR
TWO...WHICH WILL LIKELY BRING TOTALS HERE CLOSER TO ONE HALF INCH.
SREF 1/2" PROBS ARE CLOSE TO 50 PERCENT HERE...WITH THE ACTUAL
CHANCES LIKELY A LITTLE HIGHER GIVEN THAT THE SREF IS A BIT OF A
NORTHERN OUTLIER.  SNOW RATIOS WON/T BE TERRIFIC GIVEN WARM SURFACE
LAYER...AND WHILE THERE REMAINS SOME QUESTION IN TRACK...COULD
CERTAINLY SEE ADVISORY LEVEL SNOWS NORTH OF THE BRIDGE.  WARNING
AMOUNTS DO NOT LOOK LIKELY AT THIS TIME GIVEN QPF VALUES.  CERTAINLY
LOOKING LIKE A SLOPPY MORNING COMMUTE WEDNESDAY FOR EASTERN
UPPER...WITH SOME ISOLATED SLICK SPOTS ON THE BACK ROADS OF NORTHERN
LOWER.  WILL CONTINUE TO HIGHLIGHT THIS POTENTIAL IN THE MORNING
HWO.

TEMPERATURES:  NON-DIURNAL TEMPERATURE TREND TUESDAY NIGHT WITH
TEMPERATURES WARMING TO ABOVE FREEZING NORTHERN LOWER AND AROUND 30
EASTERN UPPER.  HIGHS WEDNESDAY QUICKLY MAKE A RUN AT 40 OVER MUCH
OF NORTHERN LOWER /PARTICULARLY NE/ WITH MID 30S OVER EASTERN UPPER
GIVEN THIS COOLER SCENARIO.

WEDNESDAY NIGHT: COLD ADVECTION CONTINUES...WITH AMPLE REMNANT
MOISTURE AND DEEP CYCLONIC FLOW.  CONTINUED SHSN /WITH PERHAPS A
MINOR AMOUNT OF LAKE ENHANCEMENT/ LOOK TO BE A GOOD BET /LIKE
INHERITED LIKELY POPS/ AS T8S FALL BACK INTO THE MINUS TEENS.  COULD
SEE UP TO AN INCH OVER THE HIGHER TERRAIN NORTHERN LOWER AND ALL OF
EASTERN UPPER. ARRIVING AIRMASS IS COOL FOR MID MARCH...BUT NOT AS
COOL AS IT HAS BEEN RECENTLY...WITH CLOUDS/PRECIP/WIND KEEPING LOWS
GENERALLY NEAR OR A LITTLE ABOVE 20F.

EXTENDED RANGE /THURSDAY THROUGH SUNDAY/: LOW PRESSURE CONTINUES TO
PULL AWAY FROM THE REGION /WITH PERHAPS SOME LINGERING AM
SHSN/...WITH TEMPERATURES RETURNING TO BELOW SEASONAL NORMS AS A
WEAK AXIS OF HIGH PRESSURE MOVES OVERHEAD.  ADDITIONAL SHORTWAVE
ENERGY IS SHOWN BY THE ECMWF/GFS/GGEM TO PUSH ALONG THE SOUTHERN
EDGE OF THE GRADUALLY DEEPENING EASTERN TROUGH ON FRIDAY...BUT LARGE
DISPARITIES REMAIN IN STRENGTH/LOCATION OF THE SURFACE REFLECTION OF
THIS SYSTEM WITH THE GGEM MOST AMPLIFIED AND THE GFS NOT EVEN
CLOSING OFF A SURFACE FEATURE.  TEND TO SIDE MORE WITH THE GFS/ECMWF
SIDE OF THE ENVELOPE GIVEN STRENGTHENING NORTHERN STREAM LIKELY
KEEPING ANY STORM TRACK WELL SOUTH OF OUR REGION.  BEST CHANCES FOR
SNOW LOOK TO BE OVER LOWER MICHIGAN...AND AT THIS POINT AT OR SOUTH
OF MY SOUTHERN ZONES. IT REMAINS PRUDENT...HOWEVER...TO CONTINUE LOW
CHANCE POPS UP TO THE BRIDGE UNTIL CONFIDENCE GROWS.  BEYOND THIS
SYSTEM...THERE REMAINS GOOD AGREEMENT OF ARCTIC HIGH PRESSURE
PUSHING TOWARDS THE GREAT LAKES REGION WITH A RETURN TO PERHAPS -20C
AT H8...WHICH WOULD SET THE STAGE FOR POTENTIAL RECORD LOWS TO END
THE PERIOD GIVEN THE TYPICAL CONCERNS FOR CLOUDINESS/WINDS/ETC.
CONSENSUS HIGHS 10-15F BELOW SEASONAL NORMS /MID 20S/ ARE A
REASONABLE PLACE TO START...BUT PERHAPS COULD NEED DOWNWARD
ADJUSTMENT IF THESE EARLY LOOKS AT THE GUIDANCE BECOME A FULL
REALITY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 658 AM EDT MON MAR 17 2014

...VFR THROUGH THE TAF PERIOD...

HIGH CLOUDS CONTINUE TO STREAM OVERHEAD...WITH THICKER MID CLOUD
SET TO ARRIVE LATE MORNING/AFTERNOON AND HOLD THROUGH THE NIGHT.
MAYBE A FLURRY ACROSS PLN TONIGHT. SE WINDS AOB 10KT WITH MINIMAL
GUSTINESS TODAY WEAKENING AT NIGHT. LOW LEVEL WIND SHEAR WAS
MARGINAL AT BEST...MAYBE IT COULD GET BACK INTO THE TAFS IF WINDS
INCREASE ALOFT.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.

&&

$$

UPDATE...SMD
SYNOPSIS...ARNOTT
SHORT TERM...SMD
LONG TERM...ARNOTT
AVIATION...SMD