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 281703
AFDAPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1203 PM EST FRI NOV 28 2014

.SYNOPSIS...
ISSUED AT 405 AM EST FRI NOV 28 2014

HIGH PRESSURE ACROSS THE GREAT LAKES WILL SLIP EAST OF THE STATE TODAY...
ALLOWING WARMER AIR TO BEGIN SPREADING INTO THE REGION. BUT THIS
WILL ALSO BRING A BATCH OF LIGHT SNOWFALL ACROSS NORTHERN MICHIGAN
THIS AFTERNOON THROUGH TONIGHT...AND A FEW MORE INCHES OF
ACCUMULATION. WARMER AIR CONTINUES TO SPREAD INTO THE GREAT LAKES
FOR A GOOD PART OF THE WEEKEND. BUT THIS WILL ALSO BRING SOME
LIGHT RAIN...DRIZZLE AND FOG POSSIBILITIES BACK INTO THE PICTURE
BEFORE ANOTHER SHOT OF COLDER AIR ARRIVES EARLY NEXT WEEK.

&&

.UPDATE...
ISSUED AT 959 AM EST FRI NOV 28 2014

NOT A WHOLE LOT OF CHANGE TO INHERITED FORECAST. DID SLOW DOWN
ARRIVAL OF WIDESPREAD LIGHT SNOW BY A FEW HOURS AS MID LEVELS HAVE
BEEN SLOW TO SATURATE AND CURRENT BAND OF STRONGEST FORCING SLIDES
BY TO OUR SOUTHWEST. STILL THINKING AT LEAST THE SOUTHWEST HALF OF
THE AREA WILL SEE PERSISTENT LIGHT SNOW BY THIS AFTERNOON...WITH
SOME LIGHT ACCUMULATIONS BY EVENING.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 405 AM EST FRI NOV 28 2014

OVERVIEW: UPPER TROUGH AXIS AND CORE OF COLDEST AIR NOW ADVANCING
EASTWARD OUT OF THE GREAT LAKES...WHILE FLOW PATTERN ACROSS THE
CONUS IS ONCE AGAIN FLATTENING OUT THANKS TO DEEP LOW PRESSURE IN
THE FAR EASTERN PACIFIC PRESSING INTO THE WEST COAST. THIS WILL OPEN
THE DOOR TO WARMER AIR TO AGAIN SPREAD BACK THROUGH THE EASTERN
CONUS IN THE COMING DAYS AND BRING A BIT OF A "WARM UP." HERE AT
HOME...SFC RIDGE AXIS CONTINUES TO BUILD INTO THE GREAT LAKES THIS
MORNING. NW FLOW AND LINGERING LAKE SNOW SHOWERS HAVE PERSISTED
THROUGH A GOOD PART OF THE NIGHT...BUT DWINDLING AND SHIFTING INTO
THE NRN SNOW BELTS AS LOW LEVEL FLOW FINALLY BACKING MORE WESTERLY
WITH TIME. UPSTREAM...ELONGATED AXIS OF WARM ADVECTION STRETCHES
FROM THE NRN PLAINS INTO THE MIDWEST SPREADING ANOTHER ROUND OF
LIGHT SNOW INTO THE FAR WESTERN GREAT LAKES.

TODAY...SFC RIDGE AXIS PUSHES EAST OF THE REGION THIS
MORNING...WHILE LOW LEVEL MEAN FLOW BACKS SOUTHWESTERLY. THIS WILL
PUSH REMAINING LIGHT LAKE EFFECT SNOW SHOWERS UP ALONG THE NW
MICHIGAN SHORELINE INTO THE STRAITS WITH JUST MINOR LIGHT
ACCUMULATIONS ANTICIPATED. MEANWHILE...AFOREMENTIONED PUSH OF WARMER
AIR INTO THE GREAT LAKES BEGINS LATER THIS MORNING AND CONTINUES
THROUGH THE AFTERNOON INTO TONIGHT...SPREADING UPSTREAM SNOWFALL W-E
ACROSS THE CWA. HAVE SLOWED ARRIVAL OF HIGHER POPS INTO THE
AFTERNOON WITH ARRIVAL OF STRONGER QG-ASCENT AND WEDGE OF DRIER MID
LEVEL AIR FINALLY SATURATES. BUT STRONGEST FORCING AND "HIGHER" QPF
IS STILL LOOKING TO SLIDE ACROSS NRN AND CENTRAL LOWER MICHIGAN
WHERE AN INCH OR TWO OF SNOW IS EXPECTED THROUGH THE DAY INTO THIS
EVENING. SW FLOW LAKE ENHANCEMENT MAY ADD A LITTLE BIT MORE TO AREAS
AROUND THE STRAITS AND WEST ACROSS MACKINAC COUNTY. DONT THINK IT
WILL RISE TO ADVISORY LEVEL ACCUMULATIONS...BUT AS USUAL...DAY SHIFT
WILL NEED TO KEEP AN EYE ON HOW THINGS UNFOLD.

TONIGHT...AXIS OF WARM ADVECTION FORCING/LIGHT SNOWFALL SLIPS EAST
OF THE REGION WHILE THINGS DRY OUT A BIT UPSTAIRS. WILL KEEP SOME
LIGHT SNOW CHANCES GOING OVERNIGHT...ALTHOUGH PATCHY FREEZING
DRIZZLE REMAINS A POSSIBILITY AS FORECAST SOUNDINGS SUGGEST SOME
MODEST DRYING ABOVE -10C.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 405 AM EST FRI NOV 28 2014

HIGH IMPACT WEATHER POTENTIAL: THE MIXED PRECIPITATION SATURDAY
MORNING MAY CONTAIN FREEZING RAIN. OTHERWISE, LAKE EFFECT IN THE
LATER PERIODS.

FORECAST CHALLENGES: DETERMINING THE RAIN/FREEZING RAIN/SNOW AREA AS
THE WARM ADVECTION RETREATS NORTHWARD PRIOR TO THE COLD FRONT MOVING
INTO THE UPPER GREAT LAKES.

OVERVIEW(ANALYSIS AND FORECAST)...WEAKLY AMPLIFIED RIDGE/TROUGH
PATTERN OVER THE CONUS THIS MORNING WITH THE TROUGH AXIS EAST OF THE
UPPER GREAT LAKES AND THE SFC HIGH BUILDING INTO THE LOWER OHIO
VALLEY. FRIDAY`S WARM ADVECTION SNOW GIVES WAY TO THE MID-LEVEL
MOISTURE STRIPPING OUT ENOUGH TO PRODUCE A LIGHT RAIN/FREEZING RAIN
SCENARIO/SNOW SCENARIO, MAINLY IN THE HIGHER ELEVATIONS. THEN AS THE
REST OF THE FORCING AND MOISTURE LEAVES THE REGION, MELTING AND LOW
LEVEL MOISTURE WILL PRODUCE FOG OVER THE SNOW PACK. SUNDAY, THE COLD
FRONT MOVES THROUGH AND BRINGS THE COLD AIR BACK INTO THE UPPER GREAT
LAKES AND SETS OFF LAKE EFFECT SNOW WHICH STAYS UNTIL MONDAY. MODELS
DISAGREE ON THE NEXT SYSTEM AFFECTING THE REGION ON TUESDAY, BUT DO
AGREE ON THE SNOW STARTING AGAIN WITH LES, AND THEN SYSTEM SNOW.

(11/29)SATURDAY...THE WARM FRONT PUSHES INTO THE SW COUNTIES BY 00Z.
INITIALLY THERE IS A DRY PATCH IN THE MID-LEVELS (AROUND 700 MB).
LOOKING AT THE SOUNDINGS OVER THE REGION, E UPPER SHOULD REMAIN ALL
SNOW AS THE MOISTURE REMAINS INTACT ENOUGH TO CONTINUE SNOW
PRODUCTION. IN N LOWER HOWEVER, THE ISSUE BECOMES THE DRY SLOT AND
THE WARMING TO NEAR 0C BY 18Z AT 850 MB. THE SFC TEMPERATURES ARE
STILL EXPECTED TO BE BELOW FREEZING. HOWEVER, THE ECMWF IS SHOWING
BETTER MOISTURE IN THE COLUMNS, WITH THE TEMPERATURE PROFILES NOT
GETTING ABOVE FREEZING. SO SNOW IS POSSIBLE, AND THUSLY, HAVE LEFT
THE FORECAST WITH RAIN/FREEZING RAIN/SNOW. LOOKS LIKE THE ONLY PLACE
THAT WON`T HAVE MORNING FZDZ/FZRA IS ALONG THE LAKE MICHIGAN SHORE
WHERE THE SFC TEMPERATURES QUICKLY GET ABOVE FREEZING. AFTER 18Z,
THE SFC TEMPERATURES RISE ABOVE 0C, SO WILL EXPECT THAT RAIN WILL BE
PREDOMINATE, WITH A MIX IN E UPPER.

SATURDAY NIGHT...MID LEVEL AND LOW LEVEL DRY SLOTS MOVE OVER THE
REGION, STOPPING THE RAIN. HOWEVER, THERE IS SOME LOW LEVEL
MOISTURE, THAT WITH DEWPOINTS OVER FREEZING AND A HEALTHY SNOW PACK,
WILL EXPECT THAT FOG WILL RESULT AND CONTINUE OVERNIGHT.

(11/30)SUNDAY...THE FOG WILL BEGIN TO DISSIPATE AS THE COLD FRONT
BEGINS TO PUSH ITS WAY BACK INTO THE UPPER GREAT LAKES. 850 MB
TEMPERATURES FALL QUICKLY FALL TO BELOW -10C BY 00Z, AND WITH THE
WATER TEMPERATURES AROUND +5C TO +6C WILL EXPECT THAT SNOW BANDS
WILL BEGIN FORMING BY THE END OF THE DAY. THE SNOW BANDS WILL BE
MAINLY NNW BANDS OVERNIGHT, SO WILL EXPECT THAT INITIALLY SNOW WILL
FALL IN THE NW FLOW COUNTIES DURING THE DAY, AND SHIFT IN THE
EVENING SETTLING OVER THE NNW COUNTIES NEAR TVC BY THE MORNING.

EXTENDED (MONDAY THROUGH THURSDAY)...(12/1)MONDAY...THE NNW FLOW LES
WILL CONTINUE INTO THE DAY AS THE MOISTURE REMAINS PRETTY DECENT,
BUT WITH THE SFC HIGH MOVING THROUGH THE FORECAST AREA BY THE
EVENING, WILL EXPECT THAT THE SNOW WILL COME TO A HALT.
(12/2)TUESDAY...THE DAY STARTS DRY, BUT THE CHANCES FOR SNOW MOVING
INTO THE REGION INCREASE AS THE NEXT SYSTEM MOVES INTO THE UPPER
GREAT LAKES. THE GFS CONTINUES THE IDEA, BUT THE ECMWF IS HOLDING
BACK AND MAY KEEP THE REGION DRY. (12/3)WEDNESDAY...THE 500 MB
TROUGH DROPS INTO THE REGION SO THERE IS A CHANCE FOR SNOW AS THIS
HAPPENS. IT LOOKS LIKE IT MAY DRY OUT OVERNIGHT.
(12/4)THURSDAY...MODELS DIFFER ON WHETHER THE NEXT SYSTEM MOVES IN
(GFS) OR THE HIGH PRESSURE REMAINS IN CONTROL (ECMWF).

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1158 AM EST FRI NOV 28 2014

WIDESPREAD LIGHT SNOW EXPECTED TO SPREAD ACROSS ALL TAF SITES
LATER THIS AFTERNOON THROUGH MUCH OF THE OVERNIGHT...PRODUCING
MVFR/OCCASIONAL IFR CONDITIONS. SNOW INTENSITY CHANGES WILL BE
FREQUENT...SUGGESTING IFR CONDITIONS WILL BE INTERMITTENT. MID
LEVEL MOISTURE BEGINS TO STRIP OUT LATE...AND ESPECIALLY SATURDAY
MORNING...SUGGESTING FZDZ MAY ENTER THE MIX. CIGS WILL CONTINUE TO
LOWER DURING THE MORNING AS THIS OCCURS...POSSIBLY SUPPORTING MORE
WIDESPREAD IFR CONDITIONS. LIGHT WINDS THROUGHOUT THIS TAF PERIOD.

&&

.MARINE...
ISSUED AT 405 AM EST FRI NOV 28 2014

HEADLINE FREE THROUGH TONIGHT WITH WINDS VEERING SOUTHWEST TODAY.
WINDS INCREASE ON SATURDAY AND ANOTHER ROUND OF SMALL CRAFT
ADVISORIES WILL BE NEEDED ON THE LAKES.


&&

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

$$

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


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