000
FXUS63 KGRB 251137
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
537 AM CST SUN JAN 25 2015

UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND MONDAY
ISSUED AT 359 AM CST SUN JAN 25 2015

SKY COVERS AND TEMPERATURES TODAY AND TONIGHT...AND PCPN TRENDS
LATE TONIGHT INTO MONDAY...ARE THE MAIN FCST CONCERNS.

THE ARCTIC FRONT HAS MOVED WELL SOUTH OF THE REGION EARLY THIS
MORNING...AND TEMPERATURES CONTINUE TO FALL DESPITE THE PRESENCE
OF WIDESPREAD LOW CLOUDS. CLEAR SKIES WERE OBSERVED NORTH OF LAKE
SUPERIOR...BENEATH THE ARCTIC HIGH...AND SOME BREAKS IN THE CLOUDS
WERE ALSO NOTED IN PARTS OF THE EASTERN U.P. AND NORTHERN LOWER
MI. PCPN WITH THE CLIPPER SYSTEM HAS REMAINED SOUTHWEST OF THE
FCST AREA.

ASIDE FROM A FEW FLURRIES DUE TO THE DEPARTING CLIPPER SYSTEM
AND NE FLOW OFF THE GREAT LAKES...A DRY DAY IS IN STORE. EXPECT
WIDESPREAD CLEARING TO OCCUR BY THIS AFTERNOON AS DRY AIR
CONTINUES TO ADVECT INTO THE REGION AND THE SFC HIGH DROPS SE
INTO WI. HIGH TEMPS SHOULD BE IN THE UPPER TEENS AND LOWER 20S.
BRISK NE WINDS IN THE FOX VALLEY/LKSHR AREAS WILL DECREASE LATE
IN THE DAY.

HAVE LOWERED MIN TEMPS A FEW DEGREES TONIGHT...AS CLEAR SKIES AND
LIGHT WINDS SHOULD ALLOW TEMPS TO DROP OFF IN THE EVG BEFORE
WAA CLOUDS ARRIVE. THE WAA...COMBINED WITH THE APPROACH OF S/W
TROF LATE...SHOULD GENERATE A CHANCE OF LIGHT SNOW OVER OUR FAR
NW COUNTIES TOWARD DAYBREAK ON MONDAY.

ON MONDAY...MODELS OFFER DIFFERING OPINIONS ON THE NEXT CLIPPER
SYSTEM. GIVEN THAT THE CURRENT CLIPPER WENT FARTHER SOUTHWEST
THAN EXPECTED...SUSPECT THAT THE ECMWF`S FARTHER SW TRACK ON
MONDAY MAY BE THE WAY TO GO. HOWEVER...RECENT MODEL TRENDS DO
NOT INSPIRE A HIGH LEVEL OF CONFIDENCE. WILL GO WITH MID-RANGE
(HIGH CHC/LOW LIKELY) POPS...WITH ACCUMS GENERALLY IN THE
1-2 INCH RANGE. SHALLOWING MOISTURE IN OUR SW COUNTIES LATE IN
THE DAY MAY RESULT IN A CHANCE OF FREEZING DRIZZLE...BUT THIS
IS LESS LIKELY IF THE ECMWF STORM TRACK VERIFIES.

.LONG TERM...MONDAY NIGHT THROUGH SATURDAY
ISSUED AT 359 AM CST SUN JAN 25 2015

AT 500MB...EAST COAST TROUGH AND WESTERN RIDGE WILL DOMINATE THE
PATTERN DURING THE PERIOD. FIRST CLIPPER SYSTEM WILL EXIT THE AREA
MONDAY NIGHT...WITH LAKE EFFECT SNOW SHOWERS LINGERING INTO TUESDAY
MORNING ACROSS THE NORTH. NEXT CLIPPER SYSTEM WILL DROP SOUTHEAST
INTO THE AREA WEDNESDAY NIGHT INTO THURSDAY. A LOT OF ISSUES TO
DEAL WITH WITH RESPECT TO LOCATION OF CLIPPER SYSTEM AND WILL IT
TAP DRIER TO THE EAST/NORTHEAST AT THE ONSET OF THE SYSTEM.
UNLIKE THE LAST FEW CLIPPER SYSTEMS...THIS FEATURE SHOULD HAVE A
PRONOUNCED INVERTED TROUGH ON THE NORTH SIDE OF THE SYSTEM TO
FOCUS CONVERGENCE AND DEVELOP SNOW ALONG THIS BOUNDARY EVEN IF
CLIPPER SYSTEM CONTINUES TO TREND SOUTH. STILL A LOT OF
UNCERTAINTY WITH SNOW AMOUNTS...AS INVERTED TROUGHS CAN PRODUCE
MORE SNOW THAN WHAT YOU WOULD THINK ON TOP OF THE SYNOPTIC SYSTEM.

IT APPEARS THE ARCTIC FRONT WILL SWEEP ACROSS THE REGION LATE FRIDAY
NIGHT AND SATURDAY. THE ARCTIC FRONT WILL BE ACCOMPANIED BY SNOW
SHOWER ACTIVITY AND FALLING TEMPERATURES DURING THE DAY SATURDAY.
SUNDAY AND MONDAY WILL BE DOWN RIGHT COLD BASED ON 00Z ECMWF.
&&

.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 528 AM CST SUN JAN 25 2015

MVFR CIGS AND SCATTERED FLURRIES WERE FOUND ACROSS THE REGION EARLY
THIS MORNING. GUSTY NE WINDS WERE OCCURRING...ESPECIALLY OVER THE
FOX VALLEY AND LAKESHORE AREAS.

LOW CLOUDS ARE EXPECTED TO BREAK UP TODAY AS DRIER AIR MOVES INTO
THE REGION AND HIGH PRESSURE APPROACHES. HOWEVER...CONFIDENCE IN
THE PRECISE TIMING OF THE CLEARING IS LOW. FOR NOW...HAVE BROUGHT
THE CLEARING INTO THE TAF SITES BETWEEN 17Z-19Z.

MID-LEVEL CLOUDS WILL INCREASE TONIGHT AHEAD OF THE NEXT CLIPPER
LOW PRESSURE SYSTEM. PATCHY LIGHT SNOW IS EXPECTED TO PUSH INTO
PARTS OF NC WI TOWARD DAYBREAK.

&&

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

$$

SHORT TERM.....KIECKBUSCH
LONG TERM......ECKBERG
AVIATION.......KIECKBUSCH