000
FXUS63 KGRB 060456
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
1056 PM CST WED MAR 5 2014

UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE

.ISSUED AT 924 PM CST WED MAR 5 2014

HIGH PRESSURE RIDGE VERY SLOWLY DRIFTING SOUTHEAST. ASSOCIATED
AIRMASS VERY DRY. ONLY SCT-BKN HIGH CLOUDS GRAZING THE SOUTHERN
FOX VALLEY. 11U-3.9U SAT IMAGERY CLEARLY SHOWS LOW CLOUDS OVER
IOWA SPREADING NORTHWARD INTO SOUTHERN MINNESOTA AS LOW-LEVEL
SOUTHERLY FLOW INCREASES AHEAD OF APPROACHING FRONTAL SYSTEM NOW
APPROACHING THE WESTERN DAKOTAS. DOES NOT APPEAR THIS CLOUD DECK
WILL AFFECT THE FORECAST AREA OVERNIGHT. TEMPERATURES HAVE FALLEN
VERY RAPIDLY OVER PARTS OF NORTHEAST AND EASTCENTRAL WISCONSIN
UNDER CLEAR SKIES AND WHEN WINDS GO LIGHT. LOWERED MINS BY SEVERAL
DEGREES OVER THIS PART OF THE STATE. HAVE ALREADY FALLEN TO -2 IN
GRB LAST HOUR. TEMPERATURES OVER OCONTO AND MARINETTE COUNTIES
HAVE FALLEN TO -5 TO -8 F. MAY NEED TO ADJUST MINS EVEN A FEW
DEGREES LOWER.

AS FRONTAL SYSTEM APPROACHES FROM THE WEST ON THURSDAY...EXPECT
AN INCREASE IN MAINLY HIGH AND MID-LEVEL CLOUDS. AFOREMENTIONED
STRATUS DECK OVER IOWA...MAY BEGIN TO WORK ITS WAY INTO CENTRAL
WISCONSIN LATER THURSDAY MORNING. SURFACE GRADIENT WILL TIGHTEN
AHEAD OF APPROACHING FRONTAL SYSTEM...THUS EXPECT SOUTHERLY WINDS
TO INCREASE AS THE DAY PROGRESSES...WITH PERHAPS SOME WIND GUSTS
TO AROUND 20 MPH THURSDAY AFTERNOON OVER CENTRAL SECTIONS.

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 310 PM CST WED MAR 5 2014

PRECIPITATION CHANCES AND TYPE ON THURSDAY NIGHT AND FRIDAY ARE
THE MAIN CONCERNS DURING THIS PART OF THE FORECAST. WARM ADVECTION
AHEAD OF AN APPROACHING SURFACE SYSTEM AND MID LEVEL SHORT WAVE
WILL RESULT IN A LAYER OF ABOVE FREEZING AIR...GENERALLY IN THE
950-750MB RANGE...ACROSS MUCH OF THE AREA FROM THURSDAY EVENING
THROUGH MUCH OF THE DAY ON FRIDAY. BUFKIT TIME SECTIONS SHOWED
SOME DRY AIR...SO THERE IS STILL SOME UNCERTAINTY AS TO WHETHER
ANY PRECIPITATION ACTUALLY FALLS. WPC GUIDANCE HAS AT LEAST SOME
MEASURABLE FREEZING RAIN ACROSS THE NORTHWEST HALF OF THE FORECAST
AREA THURSDAY NIGHT...BUT NO MEASURABLE SNOW...SLEET OR FREEZING
RAIN FOR THE AREA ON FRIDAY. HAVE NOTHING HIGHER THAN CHANCE POPS
DUE TO THE PRESENCE OF THE DRY AIR AND LOW GUIDANCE POPS. MENTIONED
FREEZING RAIN CHANCES IN THE FORECAST THURSDAY NIGHT AND FRIDAY
MORNING...ALONG WITH A CHANCE OF SNOW AND SLEET. CHANGED WEATHER
TYPE TO SLEET OR SNOW ACROSS THE ENTIRE AREA WITH RAIN ALSO
POSSIBLE IN THE SOUTHEAST AS SURFACE TEMPERATURES WARM INTO THE
LOWER AND MIDDLE 30S ON FRIDAY.

HIGH TEMPERATURES WILL REMAIN IN THE 20S ON SATURDAY IN THE WAKE
OF THE COLD FRONT...BUT WARM ADVECTION SHOULD KICK IN AGAIN SUNDAY
INTO MONDAY SO A WARMING TREND IS EXPECTED WITH HIGHS NEAR NORMAL
BY MONDAY. THERE MAY BE A CLIPPER SYSTEM OR TWO FOR EARLY NEXT
WEEK...BUT TIMING AMONG MODELS IS UNCERTAIN...LEADING TO A LOW
CONFIDENCE PRECIPITATION FORECAST. EXPECT TEMPERATURES TO BE A BIT
COLDER THAN NORMAL ON TUESDAY AND WEDNESDAY.
&&

.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1052 PM CST WED MAR 5 2014


SURFACE HIGH PRESSURE CURRENTLY OVER THE FORECAST AREA WILL VERY SLOWLY
DRIFT SOUTHEAST OVERNIGHT. AIRMASS ASSOCIATED WITH THIS SYSTEM IS VERY
DRY THUS DO NOT EXPECT MUCH IN THE WAY OF LOW CLOUDS...EXCEPT FOR
CIRRUS/CIRROSTRATUS DECK OVER SOUTHERN WISCONSIN. VFR CONDITIONS
SHOULD PREVAIL OVERNIGHT.

UPSTREAM...MVFR CLOUD DECK ALSO DRIFTING NORTH ACROSS IOWA INTO SOUTHERN
MINNESOTA AHEAD OF FRONTAL SYSTEM MOVING INTO THE DAKOTAS. CURRENT
TRENDS SUGGEST THIS AREA OF MVFR CLOUDS WILL NOT AFFECT ANY OF THE
FORECAST AREA TAF SITES OVERNIGHT. HOWEVER...THEY MAY WORK THEIR
WAY NORTHWARD ACROSS CENTRAL INTO NORTHWEST WISCONSIN AFFECTING
CWA...AUW AND RHI TAF SITES BY MID-MORNING.

WINDS WILL GRADUALLY VEER SOUTHEAST THEN SOUTH THURSDAY WITH
SURFACE PRESSURE GRADIENT INCREASING THROUGHOUT THE DAY. EXPECT
SOUTHERLY WINDS TO GUST TO AROUND 20 KNOTS DURING THE AFTERNOON
OVER CENTRAL AND NORTHERN WISCONSIN.

&&

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

$$

SHORT TERM.....ESB
LONG TERM......MG
AVIATION.......ESB