000
FXUS63 KGRB 250439
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
1039 PM CST SAT JAN 24 2015

UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 250 PM CST SAT JAN 24 2015

THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A SOUTHWARD
MOVING ARCTIC COLD FRONT REACHING THE U.P. BORDER EARLY THIS
AFTERNOON.  BEHIND THIS FRONT IS A VERY COLD/DRY AIRMASS AS EVIDENT
BY TEMPS ONLY IN THE SINGLE DIGITS AND DEWPOINTS BELOW ZERO OVER ONTARIO.
THE FRONT IS MAINLY INACTIVE AT THE MOMENT.  WEAK SHORTWAVE ACTIVITY
COMBINED WITH UPPER DIVERGENCE IS CONTRIBUTING TO SCATTERED SNOW
SHOWERS AND FLURRIES THAT ARE MOVING ACROSS NORTHWEST AND
NORTH-CENTRAL WISCONSIN.  EXPECTATION IS THAT THESE LIGHT SNOW
SHOWERS WILL GRADUALLY DROP SOUTH INTO CENTRAL AND EAST-CENTRAL
WISCONSIN LATER THIS AFTERNOON.  FARTHER WEST...A CLIPPER SYSTEM IS
DROPPING SOUTHEAST ACROSS THE NORTHERN PLAINS WITH A DECENT SWATH OF
SNOW OCCURRING OVER NORTH DAKOTA.  SNOWFALL POTENTIAL ALONG THE
FRONT AND FROM THE CLIPPER ARE THE MAIN FORECAST CONCERNS.

TONIGHT...AN ARCTIC COLD FRONT WILL BE DROPPING SOUTH ACROSS THE
AREA THIS EVENING WHILE A CLIPPER TRACKS SOUTHEAST ACROSS THE
CENTRAL PLAINS AND INTO THE CENTRAL MISSISSIPPI VALLEY.  PERHAPS
COULD SEE A FEW FLURRIES ALONG THE FRONT OVER FAR NORTHERN WISCONSIN
EARLY THIS EVENING...BUT ANTICIPATING BETTER CHANCES OF SNOW TO
OCCUR ALONG THE FRONT AS IT MOVES INTO CENTRAL WISCONSIN AND THE FOX
VALLEY BY MID-EVENING.  GUIDANCE IS INDICATING DECENT MID-LEVEL FGEN
DEVELOPING ALONG THE FRONT IN ADDITION TO INCREASING LARGE SCALE
FORCING AHEAD OF THE SHORTWAVE.  AS A RESULT...KEPT LOW CHANCE
POPS IN THE FORECAST THERE.  STILL ANTICIPATING A GLANCING BLOW FROM
THE CLIPPER SYSTEM AFTER MIDNIGHT...THOUGH THE LATEST RUNS OF
MESOMODELS SUGGEST THE SNOW WILL MISS THE FORECAST AREA ENTIRELY.
AREAS FROM WISC RAPIDS TO WAUTOMA COULD SEE UP TO A HALF INCH...BUT
AMOUNTS WILL BE LESS FARTHER NORTH.  WITH THE PASSAGE OF THE
FRONT...NORTHEAST WINDS WILL BECOME GUSTY OVER THE FOX VALLEY AND
LAKESHORE.  WOULD NOT BE SURPRISED TO SEE A FEW GUSTS UP TO 30 MPH.
LOWS FALLING INTO THE UPPER SINGLE DIGITS IN THE FAR NORTH...TO THE
LOWER 20S IN THE SOUTH.

SUNDAY...A SMALL CHANCE OF SNOW WILL LINGER FROM WAUTOMA TO
MANITOWOC EARLY IN THE MORNING...BUT ANY SNOW SHOULD BE DEPARTING
QUICKLY AS THE CLIPPER MOVES TOWARDS THE OHIO VALLEY.  MEANWHILE
ARCTIC HIGH PRESSURE WILL BE BUILDING SOUTHEAST OVER LAKE SUPERIOR.
THIS ARCTIC HIGH WILL BRING A VERY DRY AIRMASS INTO THE NORTHERN
PART OF THE STATE (DEWPOINTS OVER ONTARIO ARE BELOW 0F).  EVEN
THOUGH TEMPS WILL BE UNSTABLE OVER LAKE SUPERIOR AND
MICHIGAN...EXPECT THIS DRY AIR TO ERODE THE CLOUD COVER AS LAKE
EFFECT STREAMERS BECOME RETREAT CLOSER TO THE SHORELINES.  THINK ITS
POSSIBLE TO SEE SOME SUN IN THE AFTERNOON AS A RESULT.  TEMPS WILL
FALL BACK INTO THE MIDDLE TEENS TO LOWER 20S.

.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 250 PM CST SAT JAN 24 2015

WEAKENING CLIPPER SYSTEM SHOULD BRING LIGHT SNOW FOR
MONDAY THROUGH MONDAY EVENING. AN INCH OR LESS LIKELY IN MOST PLACES.
A BETTER CHANCE OF ACCUMULATING SNOW WEDNESDAY NIGHT AND THURSDAY
AS A CLIPPER SYSTEM AND ONE MOVING EAST FROM THE CENTRAL PLAINS
PHASE JUST TO OUR SOUTH. SHOULD BE ABLE TO GET A FEW INCHES DESPITE
MEAGER MOISTURE. VERY COLD AIR LOOKS LIKELY EARLY NEXT WEEK. SUBZERO
HIGH TEMPERATURES AND WIND CHILLS OF 30 BELOW POSSIBLE NEXT MONDAY
AND TUESDAY IF GFS AND ECMWF FORECASTS ARE CORRECT.
&&

.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1037 PM CST SAT JAN 24 2015

COLD FRONT WL FINISH DROPPING SWD ACRS AREA OVERNIGHT. THE FRONT
WL BE FOLLOWED BY MAINLY FLURRIES...BUT A FEW SHSN POSSIBLE S OF
AUW AND NEAR MTW. FLOW ACRS LAKES MICHIGAN/SUPERIOR WL KEEP MVFR
CIGS IN PLACE FOR A WHILE...BUT INCOMING AIR MASS IS VERY DRY...SO
STILL EXPECT CLDS TO DISSIPATE TOMORROW.
&&

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

$$

SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......SKOWRONSKI