000
FXUS63 KGRB 051755
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
1155 AM CST WED MAR 5 2014

UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND THURSDAY
ISSUED AT 242 AM CST WED MAR 5 2014

FOR THE REGIONAL WEATHER...A SHORT WAVE WAS SLIDING ALONG THE 850
BOUNDARY ACROSS NORTHEAST IOWA...AND ALONG THE WISCONSIN ILLINOIS
BORDER. BEST ACCUMULATING SNOW WELL SOUTH BUT RADAR TRENDS
INDICATE A PERIOD OF FLURRIES TO BRUSH OVER FAR SOUTHERN PORTIONS
OF THE FORECAST AREA THIS MORNING. LOCAL RADAR ALSO SHOWS WEAK
RETURNS ALONG LAKE MICHIGAN MOVING ONSHORE WITH MANITOWOC
REPORTING FLURRIES AT 07Z. ALSO AT 07Z...A 30 DBZ SNOW SHOWER WAS
MOVED ONSHORE OVER SOUTHERN KEWAUNEE AND NORTHERN MANITOWOC
COUNTIES SO ADD A SW-/SW-- MENTION FOR THE MORNING. WITH AN
EASTERLY COMPONENT IN THE WIND THE NEXT TWO DAYS...THESE LIGHT
PCPN CHANCES MAY PERSIST THROUGH THURSDAY...BUT SHOULD DIMINISH OR
END AS H80 TEMPS MODIFY. FURTHER NORTH OVER UPPER MICHIGAN...ANOTHER
BROKEN BAND OF CLOUDS NOTED WITH A SUBTLE WIND SHIFT OR FRONTAL
BOUNDARY DROPPING SOUTHWARD. A BIT DRIER AIR NOTED BEHIND THIS
BOUNDARY.

OTHERWISE HIGH PRESSURE TO DOMINATE OVER THE REGION TODAY INTO
THURSDAY. DRIER AIR WITH THE PASSING HIGH PRESSURE SYSTEM OVER THE
NORTHERN GREAT LAKES REGION SHOULD ERODE CLOUDS OVER NORTHEAST
WISCONSIN TODAY INTO TONIGHT WHILE CLOUDS MAY PERSIST A BIT MORE
OVER CENTRAL WISCONSIN WHERE RETURN FLOW BEGINS EARLIER. THESE
CLOUDS TRENDS WILL AFFECT TEMP FORECAST NEXT FEW DAYS...ESPECIALLY
OVERNIGHT LOWS TONIGHT.

SMALL PCPN CHANCES RETURN LATE THURSDAY AFTERNOON OVER NORTH
CENTRAL WISCONSIN IN THE DEVELOPING WARM AIR ADVECTION PATTERN.
MODEL TRENDS THIS MORNING IN GOOD AGREEMENT WITH OVERALL HOLDING
OFF THE LIGHT PCPN UNTIL AFTER THURSDAY AFTERNOON. DRY AIR MASS
WITH EVAP COOLING EFFECTS MORE THAN LIKELY WILL PRODUCE LIGHT SNOW
AS H850 TEMPS CLIMB TO NEAR ZERO THURSDAY AFTERNOON.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY
ISSUED AT 242 AM CST WED MAR 5 2014

THE ARCTIC AIR THAT HAS BEEN FIRMLY ENTRENCHED ACROSS THE REGION DURING
THE PAST COUPLE OF WEEKS WILL FINALLY RELENT ON FRIDAY. A COLD FRONT
APPROACHING FROM THE WEST WILL ALLOW TEMPERATURE TO RISE WELL INTO
THE 30S. SEVERAL MODELS CONTINUE TO SHOW SOME LIGHT PRECIPITATION ACROSS
THE REGION FRIDAY...WHICH SEEMS REASONABLE WITH FRONT PUSHING THROUGH
THE AREA AND MOISTURE POOLING NEAR 850M WITH FRONTAL PASSAGE. WILL
CONTINUE WITH CHANCE FOR PRECIPITATION THURSDAY NIGHT AND FRIDAY.
PRECIPITATION TYPE TRICKY DEPENDING ON SATURATION OF THE COLUMN
AND HOW WARM TEMPS GET AROUND 850MB. BUFKIT FORECAST SOUNDINGS DID
NOT CLEAR UP WHAT TYPE OF PRECIPITATION WOULD OCCUR DUE TO THERMAL
PROFILE AND DRY AIR NEAR THE SURFACE. DECIDED TO STICK WITH SNOW
AND SLEET THURSDAY NIGHT AND FRIDAY...ALTHOUGH SOME RAIN COULD BE
POSSIBLE FRIDAY AFTERNOON ACROSS EASTERN WISCONSIN AS TEMPERATURES
ARE EXPECTED TO CLIMB INTO THE MIDDLE AND UPPER 30S.

LEFT A LINGERING CHANCE OF LIGHT SNOW FRIDAY EVENING...THEN DRY
CONDITIONS ARE EXPECTED OVER THE WEEKEND. IT WILL TURN COLDER
AGAIN ON SATURDAY WITH SOME MODERATION OF TEMPERATURES ON SUNDAY
AS CLIPPER SYSTEM PASSES TO THE NORTH OF THE STATE. ANOTHER CLIPPER
SYSTEM COULD BRING ANOTHER CHANCE FOR PRECIPITATION EARLY NEXT WEEK...
ALTHOUGH PRECIPITATION TYPE WILL BE QUESTIONABLE DEPENDING OF THE
LOW LEVEL THERMAL PROFILE. TEMPERATURES SHOULD BE FAIRLY MILD ON
SUNDAY NIGHT AND MONDAY.
&&

.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1155 AM CST WED MAR 5 2014

LAKE EFFECT FLURRIES AND SNOW SHOWERS CONTINUE TO DIMINISH ACROSS
KEWAUNEE AND NORTHERN MANITOWOC COUNTIES. MTW SHOULD REMAIN OUT OF
THE LOW CLOUDS AND SNOW ASSOCIATED WITH THIS DIMINISHING BAND...AS
WINDS SHIFT TO THE EAST/SOUTHEAST THIS AFTERNOON AND EVENING AND
CONDITIONS BECOME LESS FAVORABLE FOR LAKE EFFECT ACTIVITY.
OTHERWISE...VFR CONDITIONS ARE EXPECTED ACROSS THE AREA TONIGHT
AS ARCTIC HIGH PRESSURE SLOWLY SHIFTS INTO THE EASTERN GREAT
LAKES.

MET GUIDANCE IS VERY AGGRESSIVE WITH BRINGING IN LOW CLOUDS TO
CENTRAL AND NORTH CENTRAL WISCONSIN...HOWEVER THE MAV CONTINUES
WITH THE VFR CONDITIONS ON THURSDAY. INCREASING WARM AIR AND LOW
LEVEL MOISTURE WOULD FAVOR LOW CLOUD DEVELOP...HOWEVER SOME
QUESTIONS REMAIN ON THE DEPTH AND DEGREE OF THE MOISTURE...WHICH
WILL DETERMINE WHEN THE LOW CLOUDS WILL DEVELOP. ADDED A BROKEN
MVFR CEILING FOR AUW/CWA/RHI...WITH A SCATTERED MVFR DECK FOR
GRB/ATW/MTW TO ACCOUNT FOR THE POSSIBLE LOW CLOUDS...BUT LATER TAF
FORECASTS WILL NEED TO ASSESS CLOUD POTENTIAL AGAIN. MID/HIGH
CLOUDS ARE ALSO EXPECTED ON THURSDAY...AS A COLD FRONT AND UPPER
LEVEL DISTURBANCE APPROACHES FROM THE NORTHWEST.
&&

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

$$

SHORT TERM.....TDH
LONG TERM......ECKBERG
AVIATION.......BERSCH