000
FXUS63 KGRR 250035
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
735 PM EST SAT JAN 24 2015

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 318 PM EST SAT JAN 24 2015

A COLD FRONT WILL COME THROUGH TONIGHT WITH SOME FLURRIES OR LIGHT
SNOW SHOWERS. A CLIPPER WILL PASS SOUTH OF LOWER MICHIGAN ON
SUNDAY WITH ONLY LIGHT SNOW EXPECTED. IT WILL BE COLDER ON MONDAY
AND ANOTHER CLIPPER COULD BRING LIGHT SNOW ON MONDAY NIGHT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 318 PM EST SAT JAN 24 2015

FORECAST ISSUES IN THE NEAR TERM ARE FOR LIGHT PRECIP THIS EVENING
AND SNOW AMOUNTS WITH THE CLIPPER LATE TONIGHT INTO SUNDAY.

COLD FRONT MOVES SOUTH THROUGH LOWER MICHIGAN THIS EVENING WITH VERY
LIGHT PRECIPITATION. OBSERVATIONS UP NORTH INDICATE THAT P TYPE IS
SNOW AND LAPS AND MODELS SOUNDINGS SUGGEST THAT WILL BE THE CASE
THIS EVENING. KEPT THE SLIGHT CHANCE POPS FOR THIS EVENING.

AS FOR THE CLIPPER...THE 12Z GUIDANCE IS STILL CLUSTERED ON A
TRACK WELL SOUTH OF LOWER MICHIGAN WITH THE NORTHERN EDGE OF THE
MEASURABLE SNOW EXTENDING ALONG THE I-96 CORRIDOR. WILL GO WITH AN
INCH OR TWO ALONG I-94 AND LESS THAN AN INCH TO I-96. SFC HIGH
BUILDING IN SUNDAY NIGHT WITH NE FLOW BRINGS CLEARING AND COLD
TEMPERATURES INTO MONDAY.

THE UPPER TROUGH AMPLIFIES AND GOES NEGATIVE TILT ON MONDAY AND
THE CLIPPER BOMBS OUT OVER THE ATLANTIC. A WEAK CLIPPER DIVES
SOUTHEAST ACROSS WISCONSIN AND SHEARS OUT IN THE AMPLIFYING
TROUGH MONDAY NIGHT...WITH SOME AREAS OF LIGHT SNOW MOVING INTO
WESTERN LOWER MICHIGAN AS IT DISSIPATES.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 318 PM EST SAT JAN 24 2015

NO MAJOR STORMS EXPECTED DURING THE LONG TERM. HOWEVER...A COUPLE
CHANCES OF LIGHT SNOW DO EXIST.

WEDNESDAY NIGHT AND THURSDAY ANOTHER CLIPPER WILL MOVE OVER LOWER
MICHIGAN. HOWEVER...THIS ONE WILL HAVE A LITTLE GULF INFLOW TO IT SO
THE CHANCES OF ACCUMULATING SNOW ARE HIGHER. WE COULD SEE A COUPLE
OF INCHES FROM THIS SYSTEM.

A SHOT OF ARCTIC AIR WILL MOVE SOUTH FRIDAY AND INSTABILITY WILL
INCREASE OVER THE LAKE TO THE POINT THAT LAKE EFFECT SNOW WILL
DEVELOP. H8 TEMPS FALL TO AROUND -15C CREATING FAVORABLE DELTA T/S.
MOISTURE MAY BE A BIT LACKING THOUGH AND SO ACCUMS MAY NOT BE
SIGNIFICANT.

HIGHS WILL BE MAINLY IN THE LOWER TO MID 30S THROUGH THURSDAY BEFORE
FALLING INTO THE MID 20S LATER IN THE PERIOD.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 734 PM EST SAT JAN 24 2015

CONDITIONS VARY BETWEEN MVFR AND VFR TONIGHT ACROSS THE AREA...BUT
SHOULD GRAVITATE TO MVFR IN ALL AREAS AS WE MOVE INTO THE
OVERNIGHT HOURS. A COLD FRONT WILL SAG SOUTH THROUGH THE STATE TONIGHT
AS WELL...WHICH WILL TOUCH OFF SOME LIGHT SNOW POSSIBLY MIXED WITH
SOME LIGHT RAIN EARLY THIS EVENING.

THE MVFR CONDITIONS WILL CONTINUE ON SUNDAY WITH THE CEILINGS
REMAINING IN PLACE. A CLIPPER SYSTEM WILL BRING SOME LIGHT SNOW TO
THE I94 TAF SITES LATE TONIGHT AND INTO SUNDAY. NOT EXPECTING
ANYTHING TOO HEAVY...BUT SOME MVFR VSBYS DUE TO LIGHT SNOW IS VERY
PLAUSIBLE.

BOTTOM LINE...PLENTY OF MVFR CONDITIONS ARE EXPECTED THE NEXT 24
HOURS...WITH SOME SCATTERED LIGHT SNOW TONIGHT AND MORE WIDESPREAD
LIGHT SNOW FOR THE I94 TAF SITES ON SUNDAY.


&&

.HYDROLOGY...
ISSUED AT 318 PM EST SAT JAN 24 2015

A SLIGHT AMOUNT OF SNOW MELT OBSERVED TODAY BUT NOT ENOUGH TO BE A
CONCERN. ICE ON THE RIVERS IS NOT MOVING AND WATER LEVELS ARE
HOLDING STEADY IF NOT DROPPING SLIGHTLY. SNOW AND COLD TEMPERATURES
FOR THE COMING WEEK WILL KEEP THINGS IN PLACE. CURRENTLY NO
SUSPECTED ICE JAMS IN THE AREA... BUT WILL CONTINUE MONITORING FOR
ANY THAT DO DEVELOP. SERIOUS ICE JAMS AND FLOODING CONCERNS ARE
UNLIKELY UNTIL A SIGNIFICANT WARM UP AND RAINFALL... WHICH IS
CONFIDENTLY NOT ON THE 1-2 WEEK HORIZON.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...93
AVIATION...DUKE
HYDROLOGY...CAS