Area Forecast Discussion
Issued by NWS Marquette, MI

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FXUS63 KMQT 281949
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
249 PM EST FRI NOV 28 2014

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 248 PM EST FRI NOV 28 2014

COMPLEX SHORT TERM...AS IS NORMALLY THE CASE DURING TRANSITIONS FROM
SNOW TO MIXED PRECIP AND FREEZING RAIN/DRIZZLE.

A FAST MOVING AREA OF SNOW HAS BEEN TRACKING ACROSS THE SRN CWA
TODAY AND IS NOW MOVING INTO THE SERN CWA. THE SNOW IS AHEAD OF A
WEAK SHORTWAVE CURRENTLY OVER MN AND IN AN AREA OF WAA. GENERALLY UP
TO 1 INCH OF SNOW HAS BEEN OBSERVED WITH THE SYSTEM SNOW. ADDITIONAL
MORE ISOLATED SNOW SHOWERS ARE LOCATED W/WSW OF THE CWA MORE TOWARD
THE SHORTWAVE...WHICH WILL MAINLY MOVE ALONG AND S OF THE WI BORDER
THROUGH THIS AFTERNOON.

LATER THIS EVENING INTO THE OVERNIGHT HOURS ATTENTION TURNS TO AREAS
NEAR LAKE MICHIGAN AS SLY WINDS BRING AN LES BAND NOW ARCHING TO THE
MACKINAC BRIDGE INTO THE AREA. ADDITIONALLY...UPSLOPE/ONSHORE S-SSE
FLOW WILL BRING SNOW SHOWERS TO MUCH OF THE AREA MAINLY E OF A LINE
FROM SAWYER TO MENOMINEE. DO NOT THIS THIS BAND WILL DROP AS MUCH
SNOW IN ANY ONE AREA AS PREVIOUSLY THOUGHT DUE TO MODELS SHOWING THE
BAND BEING MORE TRANSIENT. THIS MAKES SENSE GIVEN THAT LOW LEVEL
FLOW WILL VEER WITH HEIGHT AND ALSO WINDS WILL VEER WITH TIME. HAVE
AROUND 2 INCHES OF SNOW FOR THESE AREAS FROM NOW THROUGH TONIGHT.

THINGS BECOME MORE COMPLICATED LATE TONIGHT AS AN 800-900MB WARM
NOSE WITH ABOVE FREEZING TEMPS MOVES IN FROM THE SW. PRECIP AT THIS
POINT WILL BE MAINLY CONFINED TO DOWNSTREAM OF LAKE MICHIGAN...BUT
LIGHT/ISOLATED PRECIP IS ALSO POSSIBLE ELSEWHERE AS WAA CONTINUES.
ADDITIONALLY...MODELS SHOW A NARROW AREA OF PRECIP AT OR S OF
MENOMINEE ASSOCIATED WITH ANOTHER WEAK SHORTWAVE CURRENTLY OVER ND
RIGHT AROUND THE TIME OF PTYPE TRANSITION. NATURALLY LOTS OF
UNCERTAINTY HOW MUCH AND WHERE THIS PRECIP WILL OCCUR. PRECIP MAY
INITIALLY BE SLEET DURING THE TRANSITION TO FREEZING RAIN AND
EVENTUALLY FREEZING DRIZZLE AS THE DGZ DRIES OUT. IF THAT BAND DOES
SET UP OVER MENOMINEE...GREATER AMOUNTS OF INITIALLY SNOW...THEN
POSSIBLY SLEET AND FREEZING RAIN WOULD OCCUR. MAIN AREA OF CONCERN
WITH FREEZING PRECIP IS DOWNSTREAM OF LAKE MICHIGAN...MAINLY NEAR
AND E OF A LINE FROM MANISTIQUE TO NEWBERRY...WHERE FLOW OFF LAKE
MICHIGAN WILL KEEP PRECIP GOING AS LAKE EFFECT PRECIP COMES TO AN
END. TRANSITION WILL OCCUR CLOSER TO 12Z OVER THE ERN U.P. EVEN WITH
HIGH TEMPS EXPECTED TO BE IN THE MID 30S SAT...ROAD SFC TEMPS IN THE
LOW TO MID 20S WILL LEAD TO ANY LIQUID PRECIPITATION FREEZING ON
CONTACT WITH UNTREATED ROADWAYS...ESPECIALLY BARE ROADS AND ROADS
COVERED IN HARD PACKED SNOW. THEREFORE...MAIN THREAT FROM FREEZING
PRECIP IS ON ROAD/SIDEWALKS...WITH NO SIGNIFICANT THREAT TO ELEVATED
SURFACES. AM NOT VERY CONFIDENT ON AMOUNT OF FREEZING PRECIP
ACCUMULATIONS. WITH FRESH SNOW FALLING TONIGHT /HOPEFULLY HELPING TO
MAKE A CRUSTY COVER ON THE ROADS WHEN THE FREEZING PRECIP
FALLS...THUS KEEPING THE ROADS FROM BECOMING AS SLICK/...AND THE
POTENTIAL IMPACTS FROM FREEZING PRECIP BEING VERY DEPENDENT ON ROAD
SURFACE TREATMENT AND CLEARING OF THE SNOW OFF THE ROADS...WILL NOT
ISSUE ANY HEADLINES FOR THE FREEZING PRECIP. HOWEVER...WILL ISSUE AN
SPS HIGHLIGHTING THE THREAT OVER THE ERN AREAS. ANOTHER AREA THAT
MAY SEE BETTER CHANCES OF FREEZING PRECIP IS THE KEWEENAW PENINSULA
AS SSE WINDS UPSLOPE INTO NRN PORTIONS OF THE PENINSULA...BUT AM
LESS CERTAIN IN THIS AREA AND THINK AMOUNTS WILL BE LOWER THAN OVER
THE ERN UPPER PENINSULA. PRECIP SHOULD DIMINISH SOME OVER THE ERN
U.P. AND THE NRN KEWEENAW SAT AFTERNOON...BUT NOT COMPLETELY END.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 336 AM EST FRI NOV 28 2014

NAM SHOWS A SHORTWAVE OVER THE PACIFIC NW 12Z SAT WITH THE UPPER
FLOW BEING ZONAL OVER THE UPPER GREAT LAKES. THE TROUGH HEADS EAST
INTO THE NORTHERN ROCKIES 12Z SUN AND INTO THE UPPER GREAT LAKES SUN
NIGHT. COLD AIR MOVES IN ON SUNDAY AND LOOKS LIKE TEMPERATURES WILL
BE FALLING THEN. NAM SHOWS SOME 850-500 MB Q-VECTOR CONVERGENCE AND
DEEPER MOISTURE ON SUN MOVING THROUGH THE AREA.

DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST EXCEPT TO BRING
THE COLDER AIR IN QUICKER FOR SAT NIGHT INTO SUNDAY. TEMPERATURES
WILL BE FALLING ALL DAY ON SUNDAY AND HAVE A NON-DIURNAL TEMPERATURE
CURVE FOR THIS. WILL ALSO KEEP MIXED PCPN IN THE FORECAST FOR SAT
WITH FREEZING RAIN/DRIZZLE AND SNOW IN THE MORNING CHANGING TO RAIN
LATE IN THE AFTERNOON AND KEEP LOW CHANCE POPS IN THE FORECAST.

IN THE EXTENDED...GFS AND ECMWF SHOW A DEEP 500 MB TROUGH WITH VERY
COLD AIR 12Z MON OVER THE UPPER GREAT LAKES. 850 MB TEMPERATURES ARE
DOWN TO AROUND -28C AT THAT TIME. THEY QUICKLY MODIFY WITH THE
TROUGH PASSING OFF TO THE EAST 12Z TUE WITH ANOTHER UPPER TROUGH
PASSING THROUGH THE AREA TUE NIGHT. THIS UPPER TROUGH DIGS INTO THE
EASTERN U.S. 12Z THU. THE EXTENDED FORECAST PERIOD LOOKS PRETTY
ACTIVE WITH SNOW THROUGH THE PERIOD AND NO DRY WEATHER EXPECTED AS
LAKE EFFECT WILL BE IN THERE AS WELL. TEMPERATURES WILL START OFF
VERY COLD AND THEN MODIFY WITH TIME WITH TEMPERATURES REMAINING
BELOW NORMAL.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1244 PM EST FRI NOV 28 2014

AT IWD...SNOW SHOULD END EARLY THIS EVENING. -FZDZ MAY START EARLY
SAT...BUT NOT SURE HOW MUCH WILL ACCUMULATE OR HOW LONG IT WILL LAST.

AT CMX...CONDITIONS ARE NOT EXPECTED TO CHANGE MUCH THROUGH THIS
EVENING. UPSLOPE FLOW IS EXPECTED TONIGHT...WHICH MAY LEAD TO -FZDZ.
WAS CONFIDENT ENOUGH TO INCLUDE FZDZ IN THE FORECAST...BUT AM
UNCERTAIN HOW MUCH WILL ACCUMULATE AND HOW LONG IT WILL PERSIST.

AT SAW...COMPLEX FORECAST AS UPSLOPE FLOW OFF LAKE MICHIGAN WILL
LEAD TO WORSENING CONDITIONS TONIGHT. PRECIPITATION SHOULD
TRANSITION TO LIGHT FREEZING RAIN OR FREEZING DRIZZLE LATE TONIGHT
OR EARLY SAT...BUT AM UNSURE HOW MUCH WILL ACCUMULATE AND HOW LONG
IT WILL PERSIST.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 248 PM EST FRI NOV 28 2014

A DEVELOPING LOW PRESSURE SYSTEM OVER THE PLAINS WILL CONTINUE TO
MOVE TOWARD THE UPPER GREAT LAKES INTO SATURDAY. THIS WILL ALLOW FOR
WINDS TO GRADUALLY TURN SOUTH LATER TODAY INTO TONIGHT...BUT THEY
SHOULD STAY BELOW 20-25 KT. THE FRONT MOVES THOUGH SUNDAY...WHILE
STRONG ARCTIC HIGH PRESSURE BUILDS INTO THE PLAINS. THIS WILL ALLOW
NW GALES TO DEVELOP LATER SUNDAY AND CONTINUE INTO MONDAY. THE HIGH
RAPIDLY SHIFTS OVER THE LAKE MONDAY AFTERNOON...THEN MOVES INTO
QUEBEC BY TUESDAY. HIGH WILL ALLOW FOR A BRIEF RESPITE OF GALES MON
AFTN INTO MONDAY NIGHT...WITH SOUTHERLY GALES POSSIBLE AGAIN ON
TUESDAY ON THE BACK SIDE OF THE HIGH. &&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...TITUS
LONG TERM...07
AVIATION...TITUS
MARINE...TITUS






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