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000
FXUS63 KGRB 182358
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
658 PM CDT TUE JUN 18 2013

UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND WEDNESDAY
ISSUED AT 226 PM CDT TUE JUN 18 2013

TONIGHT AND WEDNESDAY

QUIET WEATHER IS EXPECTED THROUGH THE SHORT TERM. SFC ANALYSIS SHOWED
A LARGE AREA OF HIGH PRESSURE BUILDING SOUTH THROUGH THE AREA
TODAY...RESULTING IN SUNNY SKIES AND LIGHT EASTERLY WINDS.
VISIBLE SAT SHOWED LITTLE IN THE WAY OF AFTERNOON FAIR WEATHER
CLOUDS...SHOWING JUST HOW DRY AND STABLE THE AIR IS OVER
WISCONSIN. SHORTWAVE SWINGING THROUGH SOUTHERN WISCONSIN WAS
NOTED IN THE WATER VAPOR LOOP THIS AFTERNOON...HOWEVER ANY
EFFECTS FROM THIS FEATURE WILL BE WAY SOUTH AND EAST OF OUR AREA.
MAIN FORECAST CONCERN WILL BE MIN TEMPS TONIGHT AND AFTERNOON
SCATTERED CLOUDS ON WEDNESDAY.

HIGH PRESSURE WILL SIT OVER WI TONIGHT SO EXPECT CLEAR SKIES WITH
LIGHT AND VARIABLE WINDS OVERNIGHT. THIS MORNINGS MODELS HAD
SLIGHTLY COOLER TEMPS TONIGHT...SO TOOK A DEGREE OR TWO OFF OF THE
LOW TEMPS FROM THE PREVIOUS FORECAST. IN GENERAL THOUGH...LOWS
TONIGHT SHOULD NOT DROP AS LOW AS THIS MORNING DUE TO 850MB WARM
AIR ADVECTION DEVELOPING AFTER MIDNIGHT.

WEDNESDAY LOOKS LIKE A BEAUTIFUL DAY. HIGH PRESSURE WILL SHIFT
SLIGHTLY EAST BY WEDNESDAY MORNING...SO HIGH TEMPS WILL RETURN
TO NEAR NORMAL WITH THE RETURN FLOW AND SOUTHERLY WINDS. CENTRAL
AND NORTH CENTRAL WISCONSIN SHOULD SEE MORE CLOUDS TOMORROW THAN
TODAY AS MOISTURE BEGINS TO FLOW INTO THE AREA...HOWEVER SKIES
SHOULD STILL REMAIN PARTY CLOUDY TO MOSTLY SUNNY ACROSS NORTHEAST
WISCONSIN.

.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY
ISSUED AT 226 PM CDT TUE JUN 18 2013

MAIN FCST CONCERN IS PCPN TRENDS AND THE POTENTIAL FOR SEVERE TSTMS
AND HEAVY RAINFALL LATE THIS WEEK INTO EARLY NEXT WEEK.

LINGERING CANADIAN HIGH PRESSURE SHOULD KEEP WEDNESDAY NIGHT MAINLY
DRY...BUT AS THE HIGH SHIFTS EAST...SOUTHERLY RETURN FLOW WILL
BRING AN INCREASINGLY MOIST AND UNSTABLE AIR MASS INTO THE REGION
THURSDAY INTO THURSDAY NIGHT. PCPN CHANCES WILL GRADUALLY INCREASE
ACROSS OUR WESTERN AND NORTHERN COUNTIES ON THURSDAY...AND OVER
THE REST OF THE FA THURSDAY NIGHT.

A CANADIAN COLD FRONT WILL SAG SOUTH INTO THE REGION ON FRIDAY AS
A WARM FRONT LIFTS NE OUT OF THE PLAINS. EVENTUALLY THESE BOUNDARIES
SHOULD COMBINE TO PRODUCE A PERSISTENT WEST TO EAST ORIENTED FRONT
SOMEWHERE ACROSS WI...NEAR THE SOUTHERN EDGE OF THE ZONAL WESTERLY
FLOW ALOFT. SOUTH TO SOUTHWEST FLOW FROM THE SFC TO 850 MB WILL
ASCEND THE FRONTAL BOUNDARY...LEADING TO PERIODIC CONVECTIVE
DEVELOPMENT. THIS PATTERN WILL REMAIN IN PLACE FROM FRIDAY THROUGH
TUESDAY...WITH CAPES OF AT LEAST 1500-3000 J/KG (GFS HAS VALUES
AROUND 5000 J/KG AT TIMES)...MID-LEVEL LAPSE RATES OF 7-8 C/KM...
PRECIPITABLE WATER VALUES OF 1.5 TO 2 INCHES...AND DEW SFC POINTS
IN THE UPPER 60S AND 70S. THIS PATTERN IS FAVORABLE FOR MCS
DEVELOPMENT...WITH ASSOCIATED SVR TSTM AND HEAVY RAINFALL
POTENTIAL. UNFORTUNATELY...CONFIDENCE IN DETERMINING THE BEST
PERIODS FOR MCS DEVELOPMENT DURING THIS 5-DAY TIME FRAME IS LOW.
WILL CARRY MID-RANGE CHANCE POPS (40-50 PERCENT) THROUGH THE
PERIOD...AND MENTION THE POTENTIAL FOR SEVERAL BOUTS OF SVR TSTMS
AND HEAVY RAINFALL IN THE HAZARDOUS WEATHER OUTLOOK.

TEMPERATURES WILL WARM TO ABOVE NORMAL BY THURSDAY...AND SHOULD
GET WELL INTO THE 80S THIS WEEKEND AND EARLY NEXT WEEK. THE WARMTH
WILL BE ACCOMPANIED BY HIGH HUMIDITY. SUMMER APPEARS TO BE ON THE
WAY.
&&

.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 657 PM CDT TUE JUN 18 2013

SATELLITE AND SURFACE OBS SHOWED CLOUDS ACROSS THE
NORTHEAST CORNER OF WISCONSIN WITH VFR CIGS. THESE CLOUDS SHOULD
BE OUT OF THE STATE BY 03Z OR 04Z. OTHERWISE SKIES WERE CLEAR
ACROSS THE AREA AND SHOULD REMAIN THAT WAY OVERNIGHT. A WEAK
SURFACE PRESSURE GRADIENT AROUND HIGH PRESSURE OVER THE REGION
SHOULD ALLOW WINDS TO DROP OFF TO LIGHT AND VARIABLE/CALM DURING
THE NIGHT. VFR CONDITIONS SHOULD CONTINUE THROUGH WEDNESDAY.
&&

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

$$

SHORT TERM.....WOLF
LONG TERM......KIECKBUSCH
AVIATION.......MG