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000
FXUS63 KGRB 240440
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
1040 PM CST FRI JAN 23 2015

UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 250 PM CST FRI JAN 23 2015

THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SHORTWAVE
TROUGH MOVING TO THE EAST-SOUTHEAST OVER FAR NORTHWEST WISCONSIN AND
THE WESTERN UPPER PENINSULA.  AHEAD OF THIS SHORTWAVE...A MID AND
UPPER LEVEL FRONT COMBINED WILL MID-LEVEL LAPSE RATES OF 6.5-7.0
C/KM ARE CONTRIBUTING TO A BAND OF LIGHT PRECIP.  SURFACE OBS AND A
FEW REPORTS INDICATE THAT THE PTYPE IS MAINLY SNOW...OCCASIONALLY
MIXED WITH SLEET.  THE LEADING EDGE OF THIS PRECIP BAND IS
FIGHTING DRY AIR...BUT PRECIP IS REACHING THE GROUND FROM MEDFORD TO
MARINETTE.  THIS BAND OF PRECIP WILL CONTINUE TO MOVE SOUTHEAST AND
CLEAR THE FORECAST AREA EARLY THIS EVENING.  EXPECTING LITTLE TO NO
ACCUMULATION WITH ANY SNOW...BUT IT WILL LIKELY BRIEFLY DROP
VSBYS TO 2SM IN SPOTS.  BEHIND THE SHORTWAVE...AN AREA OF CLEARING
IS MOVING SOUTHEAST OVER CENTRAL MINNESOTA TO THE FAR WESTERN UPPER
PENINSULA.  THEN ANOTHER AREA OF STRATUS OVER NORTHERN MINNESOTA IS
DIVING SOUTHEAST AND WILL REACH N-C WISCONSIN BETWEEN 21Z-00Z.
PRECIP AND SKY TRENDS ARE THE MAIN FORECAST CONCERNS.

TONIGHT...THE SHORTWAVE AND MID-LEVEL FRONT WILL BE MOVING
SOUTHEAST ACROSS NORTHEAST AND EAST-CENTRAL WISCONSIN EARLY IN THE
EVENING.  LEFT A SLIGHT CHANCE OF LIGHT SNOW IN THE FORECAST UNTIL
7PM WHEN THINK ANY PRECIP WILL HAVE EXITED THE AREA.  BEHIND THE
FRONT...SKIES WILL EVENTUALLY BECOME MOSTLY CLEAR OR PARTLY CLOUDY
FOR A PERIOD THIS EVENING BEFORE LOW STRATUS OVER NORTHERN MINNESOTA
SPREADS SOUTHEAST ACROSS NORTHERN WISCONSIN.  MODELS APPEAR TO BE
TOO AGGRESSIVE WITH LOW LEVEL MOISTURE...SO SLOWED DOWN THE ARRIVAL
OF THIS STRATUS.  BUT ONCE IT MOVES IN...THINK OVERCAST CONDITIONS
WILL STICK AROUND FOR THE REST OF THE NIGHT.  THE PREVIOUS FORECAST
INCLUDED A CHANCE OF FLURRIES AND FREEZING DRIZZLE IN THE SNOWBELT.
BUT LOOKING AT PROGGED SOUNDINGS...MOISTURE DEPTH IS SHALLOW BELOW
850MB SO AM SKEPTICAL THAT PRECIP WILL OCCUR.  BUT DOES NOT TAKE
MUCH THIS TIME OF THE YEAR...SO LEFT IN THE FORECAST TO MATCH UP
WITH SURROUNDING OFFICES.  LOWS IN THE MIDDLE TO UPPER 20S.

SATURDAY...SHALLOW ARCTIC COLD FRONT WILL BE DROPPING SOUTH ACROSS
LAKE SUPERIOR TO THE U.P. BORDER DURING THE AFTERNOON.  AHEAD OF
THIS BOUNDARY...THE LOW STRATUS WILL BE HARD TO REMOVE ESPECIALLY
WITH MID AND HIGH CLOUDS MOVING OVERHEAD AHEAD OF THE NEXT CLIPPER.
PRECIPITATION AHEAD OF THE SHORTWAVE SHOULD REMAIN WELL WEST OF THE
REGION THROUGH THE AFTERNOON.  MAY SEE A FEW FLURRIES OR VERY PATCHY
FREEZING DRIZZLE ACROSS N-C WISCONSIN WITH NW WINDS IN PLACE...BUT
NOT EXPECTING ANY ACCUMULATIONS. HIGH TEMPS MAINLY IN THE LOWER TO
MIDDLE 30S.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 250 PM CST FRI JAN 23 2015

MEAN FLOW ALOFT IS EXPECTED TO REMAIN FROM THE NORTHWEST LATE THIS
WEEKEND AND THROUGHOUT THE UPCOMING WEEK.  THE MAIN FOCUS OF THIS
FORECAST IS ON SATURDAY NIGHT THROUGH MONDAY NIGHT AS A COUPLE OF
CLIPPER SYSTEMS IMPACT THE AREA. THE AXIS OF HEAVIEST SNOW WITH
THE SATURDAY NIGHT/SUNDAY SYSTEM WILL BE TO OUR SOUTHWEST...CLOSER
TO THE SURFACE LOW AND BETTER UPPER LEVEL SUPPORT. THE 12Z GFS
ONLY HAD SMALL QPF IN PARTS OF MARATHON COUNTY AND WOOD COUNTY
06Z-12Z SUNDAY...OTHER MODELS GENERALLY HAD QPF ACROSS MOST OR ALL
OF THE FORECAST AREA. KEPT CLOSE TO WHAT SURROUNDING OFFICES HAD
ALONG OUR BORDERS AND WHAT THE MAJORITY OF THE MODELS HAD FOR POPS
AND QPF. THIS RESULTED IN A SMALLER CHANGE TO FORECAST SNOW
TOTALS THAN WPC GUIDANCE...WHICH HAD LESS THAN AN INCH EVEN IN
CENTRAL WISCONSIN...WOULD SUGGEST.

SNOW TOTALS ARE EVEN MORE UNCERTAIN WITH THE NEXT SYSTEM THAT IS
EXPECTED TO BRING SNOW TO THE AREA MONDAY INTO MONDAY NIGHT. WENT
NO HIGHER THAN CHANCE POPS WITH THE SYSTEM. ONCE IT DEPARTS THERE
COULD BE SOME LAKE EFFECT SNOW SHOWERS IN FAR NORTH CENTRAL
WISCONSIN ON TUESDAY. ANOTHER SYSTEM MAY IMPACT THE AREA ON
WEDNESDAY NIGHT/THURSDAY...BUT FORECASTER CONFIDENCE THIS FAR OUT
IS RATHER POOR.
&&

.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1038 PM CST FRI JAN 23 2015

STLT IMAGERY SUGGESTS MVFR CIGS MAY NOT BE AS SOLID/PERSISTENT AS
EARLIER EXPECTED. WL PROBABLY SEE SOME BREAK IN LOWER CIGS
OVERNIGHT...SO WL ADD TO THE TAFS. SFC OBS SUGGEST A BAND OF S- WL
ACCOMPANY COLD FRONT SWD ACRS THE AREA TOMORROW AFTN/EVENING...SO
ADDED THAT AS WELL.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM.....MPC
LONG TERM......MG
AVIATION.......SKOWRONSKI