Area Forecast Discussion
Issued by NWS Gaylord, MI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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 160217
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1017 PM EDT TUE APR 15 2014

.SYNOPSIS...
ISSUED AT 340 PM EDT TUE APR 15 2014

HIGH PRESSURE WILL KEEP NORTHERLY FLOW AND UNSEASONAL COLD CANADIAN
AIR OVER THE GREAT LAKES THROUGH MID WEEK. THE NEXT WEATHER MAKER
WILL MOVE IN FOR THURSDAY AND FRIDAY AS ANOTHER STORM SYSTEM MOVES
IN FROM THE PLAINS. THE LOW IS EXPECTED TO TRACK ACROSS THE UPPER
PENINSULA...KEEPING MOST THE ACTION UP THERE FOR THURSDAY...WITH THE
FRONT TRAILING THROUGH THE LOWER...AND SHIFTING ACTIVE WEATHER TO
THE LOWER PENINSULA FOR THURSDAY NIGHT AND FRIDAY. OF THE UPCOMING
WEEKEND...SATURDAY APPEARS TO BE THE BETTER DAY FOR HUNTING
EGGS...AS ANOTHER SLOPPY SYSTEM MAY BE IN THE OFFING FOR EASTER
SUNDAY.

&&

.UPDATE...
ISSUED AT 1017 PM EDT TUE APR 15 2014

INCREASED POPS AND SNOW AMOUNTS FOR THE STRAITS AND TIP OF THE
MITT BASED ON RADAR TRENDS OVER THE PAST FEW HOURS. SHORT WAVE
SEEMS TO BE PERPETUATING OUR LAKE ENHANCED SNOW SHOWER
ACTIVITY...FOCUSING THE GREATEST POPS AND SNOW AMOUNTS ACROSS
EMMET AND CHEBOYGAN COUNTIES. HAVE INCREASE SNOW AMOUNTS TO 1 TO 2
INCHES FOR THESE AREAS...AND EXTENDED CHANCE POPS INTO THE
OVERNIGHT HOUR AS WELL. LOW LEVEL FLOW WILL SLOWLY BACK OVERNIGHT
AS THE RIDGE AXIS MOVES OVERHEAD...WITH SNOW SHOWER CHANCES ENDING
BY AROUND DAYBREAK OR SO AS LOW LEVEL FLOW BECOMES NEARLY STRAIT
FROM THE SOUTH.

&&

.SHORT TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 340 PM EDT TUE APR 15 2014

INTRIGUING LITTLE FORECAST FOR A FEW HOURS INTO THE EVENING...BUT
WITH NO MAJOR FORECAST ISSUES...SAVE FOR HOW COLD TEMPS WILL GET
TONIGHT...AND WHETHER OR NOT WE CAN SET ANY RECORDS. EARLY AFTERNOON
ANALYSIS PLACES RATHER DEEP UPPER TROUGHING OVERNIGHT...COINCIDENT
WITH QUITE THE PUSH OF COLD AIR AS H8 TEMPS HAVE DIPPED INTO THE -15
TO -17C RANGE. AS WOULD BE EXPECTED THIS TIME OF YEAR...THE LAKES
DID THEIR THING EARLY WITH SUFFICIENT SHEAR TO BAND UP SOME
STREAMERS...WHILE DIURNAL DISRUPTION IS TAKING ITS TOLL THIS
AFTERNOON...HELPING MORE THINGS INTO A MORE CELLULAR APPEARANCE
WHILE DRY AIR ENTRAINMENT HELPS DIMINISH THE OVERALL COVERAGE. A
LOOK UPSTREAM INTO THE WESTERN U.P. AND WISCONSIN SHOWS A MUCH MORE
ROBUST STRATOCU DECK WITH CONVECTIVE SNOW SHOWERS...TIED TO A VERY
SUBTLE SHORTWAVE AND QUITE STEEP LOWER LEVEL LAPSE RATES...AND (OF
COURSE) SLIGHTLY DEEPER MOISTURE.

IT IS THIS FEATURE OF INTEREST INTO THE EVENING...WITH PERSISTENT
HINTS FOR A FEW DAYS ON WEAK INCREASING LOW LEVEL FRONTOGENESIS
ARCING FROM THE CENTRAL U.P. TOWARD THE TIP OF THE MITT BETWEEN
ROUGHLY 00-05Z. BASED ON CURRENT RADAR TRENDS AND SHORT TERM
PROGS...CONTINUE TO BELIEVE THIS AXIS OF STEEP 850-700MB LAPSE RATES
WILL RESULT IN AT LEAST SCATTERED SNOW SHOWERS SHOWING SOME LIFE AS
THEY TRACK INTO THE AREA THIS EVENING...PRIMARILY ACROSS NORTHERN
LOWER. DON`T ANTICIPATE ANYTHING TOO OUT OF CONTROL...BUT GIVEN SAID
REMNANT INSTABILITY...WOULDN`T BE SHOCKED TO SEE ENOUGH TO
(RE)WHITEN THE GROUND. IN THIS SETUP...OVERNIGHT LOWS ARE TRICKY AS
THE WINDOW OF CLEARING MAY BE LIMITED...BUT HAVE TO BELIEVE GIVEN
THE ALREADY COLD START AND HIGH PRESSURE EVENTUALLY SLIDING OVERHEAD
THAT WE CAN MUSTER READINGS DOWN INTO THE TEENS...AND PROBABLY
SINGLE DIGITS IN SPOTS. THESE SHOULD BE GOOD ENOUGH TO PUSH SOME
RECORD VALUES IN MANY SPOTS...BEFORE THICKER MID/HIGH CLOUDS ROLL IN
AFTER 09Z.

.LONG TERM...(WEDNESDAY THROUGH TUESDAY)
ISSUED AT 340 PM EDT TUE APR 15 2014

HIGH IMPACT WEATHER POTENTIAL: ACCUMULATING SNOW LATE WEDNESDAY -
THURSDAY OVER EASTERN U.P.  LOWER CHANCE OF ACCUMULATING SNOW OVER
PRIMARILY NORTHEAST LOWER MICHIGAN THURSDAY NIGHT.

PATTERN SUMMARY: EARLY AFTERNOON WATER VAPOR IMAGERY SHOWS A
HIGHLY-AMPLIFIED PATTERN ACROSS NOAM WITH LONGWAVE TROUGH ANCHORED
PRETTY MUCH OVERHEAD.  THIS HAS USHERED IN A CHILLY AIRMASS CHANGE
OVER THE PAST 48 HOURS WITH A RETURN TO SOME LAKE EFFECT SNOW.  THE
PRIMARY UPSTREAM CHANGE IN THE CURRENT UPPER PATTERN THROUGH THIS
WEEK WILL BE A RETURN TO TROUGHING OVER THE GULF OF ALASKA WHICH
WILL HELP REINVIGORATE THE EASTERN PACIFIC JET CAUSING THE
DOWNSTREAM PATTERN TO BECOME MORE PROGRESSIVE.

WITH THIS TRANSITION TO A MORE PROGRESSIVE PATTERN...NUMEROUS
DISTURBANCES IN THE FLOW SHOULD ALLOW FOR A RELATIVELY UNSETTLED
PERIOD WITH NUMEROUS CHANCES OF MAINLY LIGHT PRECIPITATION.

HOVMOLLER ANALYSIS REVEALS THE LONG TERM RIDGE-TROUGH LOCATIONS
CHANGE LITTLE...WHICH INDICATES THAT DESPITE THE IMPLIED WARM UP OF
A MORE PACIFIC-DOMINATED FLOW...THE OVERALL PATTERN THROUGH 10 DAYS
FAVORS COOLER THAN NORMAL TEMPERATURES.

MIDDLE RANGE /WEDNESDAY THROUGH FRIDAY/:

COMPACT NORTHERN STREAM SHORTWAVE NOW SEEN OVER
WASHINGTON/OREGON/IDAHO WILL RACE SOUTH AND EAST AND TEAM UP WITH
LEE-SIDE CYCLONE JUST EAST OF THE ROCKIES TO PRODUCE A COMPACT
SURFACE LOW THAT WILL MOVE ACROSS THE NORTHERN PLAINS ON WEDNESDAY.
HIGH PRESSURE OVER THE GREAT LAKES REGION WILL SHIFT EAST WITH
SIGNIFICANT WARM ADVECTION THROUGH THE DAY. WHILE MID/UPPER LEVEL
CLOUDS WILL HAVE OVERSPREAD THE REGION BY MORNING...LLEVEL MOISTURE
WILL BE LACKING UNDER DRY SOUTHEASTERLY LLEVEL FLOW.  THUS...EXPECT
A DRY MORNING BEFORE SLOWLY INCREASING LLEVEL MOISTURE SHOULD ALLOW
TOP-DOWN SATURATION PROCESS TO COMPLETE AND SOME LIGHT SNOW TO BREAK
OUT FROM THE STRAITS NORTH WITH A SMALL POSSIBILITY SOUTH OF THIS
FROM M-32 NORTH.  AMAZINGLY...PTYPE SHOULD NOT BE IN QUESTION WITH
RETREATING ARCTIC AIRMASS STILL PLENTY COLD ENOUGH TO PRODUCE SNOW
AS LLEVELS SATURATE.  ALWAYS TOUGH TO ACCUMULATE SNOW IN APRIL
DURING THE DAYTIME...SO SEE NO MORE THAN A COATING...PRIMARILY ON
GRASSY SURFACES THROUGH EVENING.  HIGHS STUCK NEAR FREEZING IN
EASTERN UPPER...WITH UPPER 30S TO AROUND 40 WITH PERHAPS SOME
FILTERED SUN IN NORTHERN LOWER.

CONFIDENCE A LITTLE SHAKY FOR WEDNESDAY NIGHT AS AFOREMENTIONED LOW
WEAKENS AS UPSTREAM SHORTWAVE DAMPENS IN RESPONSE TO DOWNSTREAM
CONFLUENT FLOW.  GULF MOISTURE IS LACKING...WITH PWATS MAKING A RUN
AT 0.5-0.6".  THESE VALUES...WHILE NOT IMPRESSIVE...AREN/T BAD
DURING A POTENTIAL SNOW-PRODUCING SCENARIO.  SYSTEM WILL HAVE SOME
JET ENTRANCE REGION DYNAMICS TO WORK WITH AS A BAND OF H8-7 FGEN IN
THE REGION OF MODEST QVECTOR SUPPORT AND ISENTROPIC ASCENT SHOULD
FAVOR A BAND OF SNOW ACROSS MUCH OF UPPER MICHIGAN.  PRIMARY
QUESTIONS ARE HOW RAPIDLY THIS BAND LIFTS NORTH AND...WITH A PRETTY
WEAK LLJ RESPONSE IN THE WARM SECTOR OF THIS LOW...JUST HOW INTENSE
THE BANDING WILL BE.  THE POTENTIAL EXISTS FOR AN NEAR-ADVISORY
LEVEL SNOWFALL /BEST ESTIMATE 2-4?/...WITH A VERY QUICK DROP OFF TO
THE SOUTH ACROSS ALL OF NORTHERN LOWER.  LOWS WILL BE SIGNIFICANTLY
WARMER THAN 24 HOURS PREVIOUS...IN THE UPPER 20S NORTH TO LOWER 30S
SOUTH...WITH TEMPS STEADY OR SLOWLY RISING OVERNIGHT.

LOW PRESSURE CONTINUES TO WASH OUT OVERHEAD ON THURSDAY WITH FORCING
FOR ASCENT WANING AS MOISTURE PLUME SLOWLY SHIFTS EAST.  OUTSIDE OF
ANY RESIDUAL SNOW /EVEN MIXING WITH RAIN AT THIS POINT/ OVER EASTERN
UPPER EARLY...COULD SEE THE POTENTIAL FOR SOME SHRAS OVER NORTHERN
LOWER AS MOIST CYCLONIC FLOW CONTINUES WITH SOME AFTERNOON SHALLOW
INSTABILITY.  T9 REACH +3 OVER NORTHERN LOWER SUGGESTING HIGHS IN
THE UPPER 40S TO 50...WITH HIGHS STUCK AT OR BELOW 40 OVER EASTERN
UPPER WHERE THE SURFACE WARM FRONT NEVER ARRIVES.

HAVE TO WATCH ANOTHER SNEAKY POTENTIAL SNOW EVENT THURSDAY NIGHT AS
NEXT UPSTREAM SHORTWAVE CATCHES UP TO DEPARTING MOISTURE PLUME IN
THE PRESENCE OF A 100KT JET STREAK CENTERED OVER NORTHERN MICHIGAN
TO PROMOTE A BAND OF FRONTOGENETICALLY-FORCED PRECIPITATION OVER
CENTRAL MICHIGAN AND POTENTIALLY PARTS OF NORTHEAST LOWER.
TEMPERATURE PROFILES WOULD BE MARGINALLY SUPPORTIVE OF SNOW GIVEN
STRONG ENOUGH RATES...WITH A FEW WET INCHES OF SNOW CERTAINLY
POSSIBLE IF THIS BAND MATERIALIZES. HOWEVER...AT THIS TIME...BEST
CHANCES FOR THIS REMAIN JUST SOUTH OF THE FORECAST AREA.  WILL
HIGHLIGHT THIS POTENTIAL IN THE AFTERNOON HWO.  LOWS LOOK TO FALL TO
WITHIN A FEW DEGREES OF 30.

ANY PRECIPITATION ACTIVITY SHOULD SHIFT EAST DURING THE DAY FRIDAY
WITH POPS GRADUALLY DIMINISHING UNDER COLD ADVECTION.  COLD
ADVECTION TAKES T9 TO AROUND -4C BY AFTERNOON...INDICATING THAT
WHILE THE TREND WILL BE FOR DRYING...AND EVEN SOME AFTERNOON BREAKS
OF SUN...TEMPERATURES WILL REMAIN COLD WITH HIGHS ONLY IN THE UPPER
30S OVER EASTERN UPPER/COAST OF NW LOWER WITH 40S OVER NE LOWER
LIKELY MELTING ANY SNOW THAT FALLS THURSDAY NIGHT THROUGH DAYBREAK
FRIDAY.

EXTENDED RANGE /SATURDAY THROUGH TUESDAY/:

ECMWF/GFS COMPROMISE FAVORED THROUGH THE THIS PERIOD AS THE GGEM A
STARK OUTLIER AND NOT CONSISTENT WITH RECENT TRENDS FROM SUGGESTED
FROM HOVMOLLER ANALYSIS.

WEAK RIDGE OF HIGH PRESSURE ARRIVES SATURDAY BEHIND DEPARTING
SHORTWAVE PROMISING ANOTHER BREAK WEATHER-WISE...BUT CONTINUATION OF
TEMPERATURES BELOW SEASONAL NORMS.

GFS/ECMWF AGREEMENT WEAKENS AS WE REACH SUNDAY/MONDAY BUT THERE IS
SOME CONSENSUS OF A RETURN OF THE GULF MOISTURE STREAM AS HIGH
PRESSURE PUSHES EAST OF THE GREAT LAKES WITH SHORTWAVE TROUGHING
WELL NORTH OF THE AREA ACROSS CENTRAL CANADA...WITH MUCH WEAKER
SHORTWAVE ENERGY PASSING THROUGH THE GREAT LAKES.  SHOWER CHANCES
LOOK LIKELY DURING THIS PERIOD /PARTICULARLY OVER NORTHERN LOWER/
BUT WITH NO STRONG FORCING TO HANG YOUR HAT ON...TIMING REMAINS
UNCERTAIN WITH CHANCE POPS WARRANTED AT THIS TIME.  AIRMASS ALOFT
SLOWLY MODERATES...BUT WITH CLOUDS/POTENTIAL PRECIPITATION
CHANCES...WILL CONTINUE WITH HIGHS AT OR BELOW SEASONAL NORMS...WITH
DECENT CHANCES THAT ONE OF THESE TWO DAYS MAY END UP COOLER STILL.

THERE IS MODEST AGREEMENT IN COOL HIGH PRESSURE SETTLING INTO THE
GREAT LAKES REGION AGAIN TO END THE FORECAST PERIOD BY TUESDAY WHICH
PROMISES ANOTHER BREAK IN PRECIPITATION WITH /SORRY FOR THE BROKEN
RECORD/ CONTINUED COOLER THAN NORMAL TEMPERATURES.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 730 PM EDT TUE APR 15 2014

MAINLY VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THRU 00Z
THURSDAY AS HIGH PRESSURE SLIDES OVER MICHIGAN. THE EXCEPTION WILL
BE AT PLN WHERE LINGERING LAKE ENHANCED SNOW SHOWERS WILL
OCCASIONALLY DROP CONDITIONS TO MVFR/IFR THIS EVENING...AND THEN
INCREASING CHANCES OF LIGHT SNOW LATE WEDNESDAY AFTERNOON AND
EVENING WILL DROP CONDITIONS TO MVFR AS A WARM FRONT LIFTS INTO
NRN MICHIGAN. LIGHT/VARIABLE WINDS TONIGHT WILL SHIFT TO THE SE AT
AROUND 10 KTS ON WEDNESDAY.


&&

.HYDROLOGY...
ISSUED AT 340 PM EDT TUE APR 15 2014

STILL QUITE A FEW ISSUES ONGOING ACROSS THE SOUTHERN CWA BASED ON
CURRENT RIVER LEVELS...THOUGH THEY AREA FALLING WITH TIME. WILL GIVE
THE CURRENT FLOOD WARNING ONE MORE BOOST THROUGH TOMORROW AFTERNOON
AND SEE WHERE THINGS TAKE US. PLENTY OF ACTION WITH AN ONGOING DAM
BREAK IN EXTREME SOUTHEAST ROSCOMMON COUNTY...BUT PER EMERGENCY
MANAGER REPORTS...WAVER LEVELS ARE BEGINNING TO FALL AS THE POND
UPSTREAM OF THE DAM HAS BASICALLY EMPTIED. FLASH FLOOD WARNING WILL
REMAIN IN EFFECT THROUGH 6 PM AT WHICH TIME MANY OF THE IMPACTS
SHOULD BE GONE.

&&

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

&&

$$

UPDATE...MR
SYNOPSIS...KB
SHORT TERM...LAWRENCE
LONG TERM...ARNOTT
AVIATION...MR
HYDROLOGY...LAWRENCE






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