Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 270449
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1149 PM EST WED NOV 26 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 315 PM EST WED NOV 26 2014

...ONLY MINOR WEATHER IMPACTS ANTICIPATED THROUGH THE THANKSGIVING
HOLIDAY AND WEEKEND...

LAKE EFFECT SNOW ACCUMULATIONS OF 1 TO 3 INCHES ARE POSSIBLE ALONG
THE ENTIRE LAKESHORE WEST OF ROUTE 131 THURSDAY MORNING...AND THEN
MAINLY SOUTH OF SOUTH HAVEN / WEST OF ROUTE 131 THURSDAY
AFTERNOON. ISOLATED AMOUNTS OF 4 OR 5 INCHES ARE POSSIBLE SOUTH OF
HOLLAND BUT UNLIKELY. SNOW SHOWERS WILL BE ACCOMPANIED BY BRISK
NORTHWEST WINDS AND SLOWLY FALLING TEMPERATURES IN THE 20S.

THERE WILL LIKELY BE ANOTHER 1 TO 2 INCH SNOW ACCUMULATION ACROSS
ALL OF SOUTHWEST MICHIGAN FRIDAY AFTERNOON. THE SNOW MAY END AS A
BRIEF PERIOD OF FREEZING DRIZZLE FRIDAY NIGHT. TEMPERATURES WILL
SLOWLY RISE THROUGH THE DAY AND SHOULD BE AT OR ABOVE FREEZING BY
MID MORNING SATURDAY.

SUNDAY TRAVEL LOOKS OKAY WITH AREAS OF LIGHT RAIN / DRIZZLE AND
FOG. TEMPERATURES WILL BE WELL ABOVE FREEZING ALL AREAS.

COLD AIR RETURNS ON MONDAY WITH FLURRIES LIKELY AND FALLING
TEMPERATURES...DOES NOT LOOK LIKE LAKE EFFECT WILL BE VERY ACTIVE
AT THIS TIME WITH BLUSTERY NORTHWEST WINDS.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 222 PM EST WED NOV 26 2014
CONSIDERED AN ADVISORY FOR THURSDAY FOR COMBO OF LAKE-EFFECT AND
SOME BLOWING SNOW BUT OPTED OUT FOR NOW. OVERALL FAIRLY CONFIDENT
WITH MODEST LAKE EFFECT SNOW EVENT ON THURSDAY WITH HIGHEST TOTALS
(1 TO 3 INCHES) SOUTHWEST ALLEGAN COUNTY...VAN BUREN COUNTY AND
FURTHER SOUTH INTO NORTHERN INDIANA. JUST DONT THINK THE SNOW
INTENSITY OR TIME DURATION AT ANY ONE LOCATION WILL BE ENOUGH
IMPACT WISE...STILL THERE WILL ISOLATED SPOTS WITH SLICK ROADS AND
BRIEFLY POOR VISIBILITY.

A WEAK SHORTWAVE WITH SFC COLD AIR ADVECTION WILL INITIATE THE
LAKE-EFFECT SNOW BANDS THURSDAY MORNING BUT OVERALL FLOW BECOMES MORE
ANTICYCLONIC BY EVENING AND AS A RESULT MOISTURE / LIFT ONLY
BRIEFLY GET TO 10 KFT THURSDAY MORNING BEFORE SETTLING BACK
TOWARDS 5KFT BY EVENING. ALSO WIND DIRECTION WILL GRADUALLY SHIFT
FROM WNW EARLY TO NNW BY EVENING WITH SNOW BANDS SHIFTING
SOUTHWARD THROUGHOUT THE DAY EVENTUALLY BECOMING MAINLY SHORE
PARALLEL BY EVENING.

FRIDAY/S OVERRUNING EVENT WILL BE ASSOCIATED WITH A WEAK CLIPPER
SLIDING EAST-SOUTHEAST ALONG ADVANCING WARM FRONT. GOOD
WAA/ISENTROPIC LIFT WILL LEAD TO A LARGE AREA OF LIGHT SNOW ALONG
AND NORTH OF H85 FRONTAL INTERSECTION. GFS/ECMWF/FIM BLEND WOULD
SUGGEST HIGHEST AMOUNTS (2 TO 3 INCH) RANGE WOULD BE NORTH OF
I-96. MOST OF THE DEEPER LIFT MOVES EAST OF THE AREA BY FRIDAY
EVENING SO WOULD NOT BE SURPRISED TO SEE SOME FREEZING DRIZZLE
FRIDAY EVENING AS THERE WILL STILL BE SOME GOOD LOW LEVEL
CONVERGENCE ASSOCIATED WITH ADVANCING WARM FRONT.

.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 315 PM EST WED NOV 26 2014

THE ZONAL FLOW PATTERN BEGINS SATURDAY AND CONTINUES UNTIL THE
MIDDLE OF NEXT WEEK. WE/LL SEE TWO MAIN LOW PRESSURE SYSTEMS MOVE
ACROSS THE GREAT LAKES DURING THE PERIOD.

WARM ADVECTION PCPN WILL BE WINDING DOWN SATURDAY AS A LOW CHANCE OF
LIGHT RAIN. ZONAL FLOW USUALLY MEANS WARMER TEMPERATURES AND WE/LL
SEE TEMPS IN THE 40S OVER THE WEEKEND. A CLIPPER MOVING ACROSS THE
NRN TIER OF STATES SATURDAY WILL DRAG A COLD FRONT THROUGH THE CWA
SUNDAY NIGHT. MOISTURE IS VERY LIMITED THOUGH SO CHANCES OF SNOW
WILL BE ON THE LOW SIDE.

MONDAY WILL BE THE COLDEST DAY WITH HIGHS AROUND 30 BUT CHANCES FOR
SNOW WILL REMAIN LOW DUE TO SHALLOW MOISTURE. PCPN CHANCES WILL
INCREASE WEDNESDAY AHEAD OF THE NEXT SYSTEM...BUT MUCH OF THE PCPN
WILL BE RAIN AS TEMPS CLIMB TO AROUND 40. MIXED RAIN AND SNOW LOOKS
POSSIBLE OVER THE NRN CWA WHERE COLDER TEMPS WILL HANG ON A BIT
LONGER.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1144 PM EST WED NOV 26 2014

LIMITED IMPACTS EXPECTED THROUGH MOST OF THE NIGHT...WITH
VFR/MVFR CONDITIONS CONTINUING TO PREVAIL. LATE TONIGHT THROUGH
THURSDAY...TAF SITES CLOSER TO LAKE MICHIGAN WILL SEE A RISK FOR
IFR AND LOWER CONDITIONS. THE WIND WILL SHIFT TO THE NORTH
NORTHWEST THURSDAY AFTERNOON AND EVENING. THIS WILL CAUSE THE SNOW
BANDS TO MIGRATE CLOSE TO THE SHORELINE OR EVEN PUSH OFFSHORE.
INLAND LOCATIONS SHOULD SEE A TREND TO VFR THURSDAY AFTERNOON.
KAZO WILL BE CLOSE TO THE IMPACT SNOW BANDS INTO THURSDAY
AFTERNOON.

&&

.MARINE...
ISSUED AT 222 PM EST WED NOV 26 2014
STILL LOOKING AT POTENTIAL FOR SMALL CRAFT ADVISORY THURSDAY WITH
NEXT PUSH OF ARCTIC AIR INTO THE REGION. GUST TO 30 KTS ARE LIKELY
FOR THURSDAY MID MORNING THROUGH EARLY AFTERNOON BEFORE THEY BEGIN
TO DIMINISH. WINDS WILL THEN REMAIN BELOW ADVISORY LEVELS UNTIL
MONDAY WHEN ANOTHER ARCTIC SURGE WILL RESULT IN GUSTY NORTHWEST
WINDS AND HIGH CHOP.


&&

.HYDROLOGY...
ISSUED AT 1138 AM EST WED NOV 26 2014

FIRST AND FOREMOST...RIVER ADVISORIES CONTINUE TO DWINDLE IN TIME.
THE ADVISORIES THAT REMAIN SHOULD ONLY REACH LOW END CRITERIA
AND ARE NOT EXPECTED TO PRESENT ANY REAL PROBLEMS.

THE SECOND ITEM TO NOTE IS THE MULTIPLE CHANCES FOR PRECIPITATION
THROUGH THE WEEK. EACH EVENT IS EXPECTED TO BE RATHER LIGHT. THESE EVENTS
COME LATE TONIGHT INTO THANKSGIVING DAY AND AGAIN FRIDAY...MOSTLY IN
THE FORM OF SNOW. TEMPERATURES WILL WARM ENOUGH OVER THE WEEKEND
TO CHANGE SOME OF THE LEFT OVER PRECIPITATION TO LIGHT RAIN.
BETTER PRECIPITATION IS POSSIBLE NEAR LUDINGTON...BALDWIN AND REED
CITY...BUT EVEN THIS IS NOTHING OF ANY MAJOR CONCERN. OVERALL
PRECIPITATION AND RUNOFF FROM MELTING SNOW MAY CAUSE SOME WITHIN
BANK RISES NEXT WEEK WITH NO NOTABLE FLOOD CONCERNS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY FROM 9 AM THURSDAY TO 3 AM EST FRIDAY FOR
     LMZ844>849.

&&

$$

SYNOPSIS...COBB
SHORT TERM...COBB
LONG TERM...93
AVIATION...MJS
HYDROLOGY...JAM
MARINE...COBB






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