Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 301145
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
745 AM EDT THU OCT 30 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 330 AM EDT THU OCT 30 2014

OUR FIRST SIGNIFICANT BLAST OF COLD AIR WILL ARRIVE ON HALLOWEEN
BEHIND A STRONG COLD FRONT DROPPING SOUTH FROM CANADA. NORTH WINDS
GUSTING OVER 40 MPH COMBINED WITH TEMPERATURES IN THE 30S WILL
CREATE WIND CHILLS AROUND 20 DEGREES BY THE END OF THE DAY. ALSO
MANY AREAS WILL SEE THE FIRST SNOWFALL OF THE SEASON WITH SOME
LIGHT ACCUMULATIONS POSSIBLE ON THE GRASS. TEMPERATURES WILL
MODERATE ABOVE NORMAL NEXT WEEK.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU OCT 30 2014

FORECAST REMAINS ESSENTIALLY UNCHANGED AS 00Z MODELS REMAIN
CONSISTENT ON THE INTENSE SHORTWAVE AND COLD FRONT DROPPING SOUTH
THROUGH THE GREAT LAKES REGION LATE TONIGHT AND FRIDAY. THE MAIN
IMPACT FROM THIS SYSTEM IS GOING TO BE THE STRONG GUSTY WINDS AND
THE COLD TEMPERATURES... ESPECIALLY SINCE THIS IS THE FIRST TASTE OF
WINTER. HOWEVER THE SNOW POTENTIAL WILL NEED TO BE MONITORED TOO.

P-TYPE WITH THIS SYSTEM REMAINS CHALLENGING. THE LOW LEVEL COLD AIR
MOVES IN RATHER QUICKLY ON FRIDAY AND LOOKS TO ARRIVE WHILE THE DEEP
MOISTURE AND LIFT ASSOCIATED WITH THE UPPER LOW IS STILL OVERHEAD.
THIS COULD MAKE THINGS VERY INTERESTING AS SOUNDINGS SUPPORT SNOW
OVER MUCH OF THE AREA AFTER 18Z WHILE THERE IS EVEN SOME SEMBLANCE
OF A MID LEVEL DEFORMATION ZONE TRYING TO TAKE SHAPE OVERHEAD.

IF HEAVIER CONVECTIVE PRECIP RATES OCCUR ON FRIDAY... WHICH LOOKS
QUITE POSSIBLE...SOME QUICK WET SNOW ACCUMULATIONS ARE CERTAINLY
POSSIBLE. THE BEST POTENTIAL WOULD BE IN THE HIGHER ELEVATION
NEAR/NORTH OF U.S. 10... BUT WOULD NOT RULE OUT SOME ACCUMULATIONS
ELSEWHERE. ONE LIMITING FACTOR IS THE WARMTH OF THE GROUND THIS
EARLY IN THE SEASON... BUT HEAVIER CONVECTIVE RATES COULD EASILY
OVERCOME THIS.

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU OCT 30 2014

HIGH PRESSURE ALOFT AND AT THE SFC WILL LEAD TO FAIR SKIES SATURDAY
NIGHT THROUGH MONDAY. AS THE RIDGE MOVES EAST...A COLD FRONT WILL
APPROACH MONDAY NIGHT AND TUESDAY AND GIVE US A PRETTY GOOD CHANCE
OF RAIN. INSTABILITY IS LOW SO THUNDER ISN/T EXPECTED. A QUARTER
INCH OF RAIN SEEMS POSSIBLE WITH THE SYSTEM. A STRONG FETCH OFF THE
GULF WILL RIDE NORTHEAST AHEAD OF THE FRONT. WE`LL START TO DRY OUT
WEDNESDAY AFTER THE FRONT MOVES BY. THE AIR BEHIND THE FRONT ISN/T
COMING OUT OF NORTHERN CANADA SO WE WON/T SEE MUCH OF A TEMPERATURE
DROP BEHIND IT.

HIGHS THROUGH THE PERIOD WILL CLIMB FROM THE LOWER 40S SATURDAY TO
THE LOWER 50S BY MONDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 745 AM EDT THU OCT 30 2014

VFR CIGS AROUND 3500-4000 FT ARE EXPECTED TODAY INTO TONIGHT.
AFTER 06Z AND ESPECIALLY TOWARD 12Z FRIDAY LOOK FOR CIGS TO LOWER
INTO MVFR CATEGORY WITH RAIN SHOWERS BECOMING MORE WIDESPREAD.

THE OUTLOOK BEYOND 12Z FRIDAY IS FOR SIGNIFICANT AVIATION IMPACTS
INCLUDING NORTH WINDS GUSTING OVER 35 KTS AND FREEZING LEVELS
DESCENDING BELOW 1000 FT AGL. THIS WILL SUPPORT RAIN SHOWERS
CHANGING TO SNOW SHOWERS LEADING TO THE POTENTIAL FOR OCNL
REDUCTIONS TO VSBYS INTO THE IFR CATEGORY.

&&

.MARINE...
ISSUED AT 330 AM EDT THU OCT 30 2014

THE GALE WARNING FOR FRIDAY/FRIDAY NIGHT LOOKS GOOD AND NO CHANGES
NEEDED THERE. IT IS POSSIBLE A FEW BRIEF GUSTS TO 50 KNOTS COULD
OCCUR... WHICH IS STORM WARNING CRITERIA... HOWEVER THE BULK OF THE
EVENT SHOULD BE A GALE.


&&

.HYDROLOGY...
ISSUED AT 343 PM EDT WED OCT 29 2014

WHATEVER QPF WE WILL SEE THIS WEEK WILL BE LIGHT SO IT SHOULD HAVE
NO IMPACT ON AREA RIVERS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...GALE WARNING FROM 8 AM FRIDAY TO 5 AM EDT SATURDAY FOR
     LMZ844>849.

&&

$$

SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...93
AVIATION...MEADE
HYDROLOGY...WDM
MARINE...MEADE






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