Area Forecast Discussion
Issued by NWS Green Bay, WI

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000
FXUS63 KGRB 162237
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
537 PM CDT THU OCT 16 2014

UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 251 PM CDT THU OCT 16 2014

CLEARING LINE PRETTY ABRUPT BASED ON VISIBLE SATELLITE IMAGERY.
IT WAS CLOUDY AND AROUND 50 OVER FAR NORTHEAST AND EAST-CENTRAL
WISCONSIN. WHERE SKIES CLEARED...TEMPERATURES REBOUNDED INTO THE
LOWER TO MIDDLE 60S AT MARSHFIELD...WISCONSIN RAPIDS AND WAUTOMA.
SOME CONCERN THAT CLEARING WILL STOP THIS EVENING ONCE THE SUN SETS.

IMPRESSIVE SHORTWAVE WILL DROP SOUTHEAST INTO THE REGION OVERNIGHT
AND FRIDAY MORNING. CLOUDS WILL BE ON THE INCREASE FOR PLACES THAT
CLEARED OUT THIS AFTERNOON AND TONIGHT. THIS SHORTWAVE FEATURE HAD
A BAND OF PRECIPITATION WITH BASED ON REGIONAL RADARS OVER THE
PLAINS. THERE WERE ALSO A FEW LIGHTNING STRIKES WITH THIS FEATURE
AS WELL. DECIDED TO ADD A MENTION/DEPICTION OF THUNDER ACROSS THE
FAR NORTH LATE TONIGHT INTO FRIDAY MORNING. MAIN STORY BEHIND THIS
SYSTEM WILL BE STRONG NORTHWEST WINDS.

MODELS INDICATED BEST PRESSURE RISES ACROSS THE FORECAST AREA
FRIDAY AFTERNOON ALONG WITH STRONGEST DOWNWARD VERTICAL MOTION AT
700MB TOWARDS 00Z. THE COMBINATION OF INCREASING STRONG LOW LEVEL
WINDS AND THE ABOVE MENTIONED REASONS...THINK WIND GUSTS ACROSS
NORTHEAST WISCONSIN WILL BE IN THE 30 TO 40 MPH RANGE WITH HIGHER
GUSTS POSSIBLE ACROSS DOOR COUNTY WHERE BETTER MIXING WILL OCCUR FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 251 PM CDT THU OCT 16 2014

BESIDES THE CONTINUATION OF THE PRECIP FROM FRIDAY INTO FRIDAY
NIGHT...THE ONLY OTHER SYSTEM TO CONTEND WITH WILL BE THE CLIPPER
TYPE SURFACE LOW THAT WILL TRACK ACROSS THE REGION SUNDAY NIGHT INTO
EARLY MONDAY.  THE LATEST MEDIUM RANGE MODELS HAVE TRENDED TO THE
NORTHEAST WITH THE SURFACE LOW TRACK...BUT THE ECMWF APPEARS TO LIE
IN THE MIDDLE OF THE TIGHTLY CLUSTERED SOLUTION ENVELOP.  WILL RELY
ON ITS SOLUTION FOR THIS FORECAST.  DURING LATER PERIODS...THERE IS
BETTER AGREEMENT BETWEEN THE GFS/GEM/AND ENSEMBLE MEAN.

FRIDAY NIGHT THROUGH SUNDAY...A SHORTWAVE TROUGH WILL BE EXITING THE
REGION EARLY FRIDAY NIGHT...BUT PLENTY OF MOISTURE WILL EXIST
THROUGH THE COLUMN BEHIND THE WAVE...WHICH WILL BE GOOD FOR SHOWERS
OVER EASTERN WISCONSIN AND ALSO OVER N-C WISCONSIN WHERE FLOW WILL
BE NNW OFF LAKE SUPERIOR.  SOME SNOW WILL LIKELY MIX IN OVER N-C
WISCONSIN BY LATE IN THE EVENING...PERHAPS TURNING TO ALL SNOW
OVERNIGHT.  SMALL ACCUMULATIONS ON GRASSY SURFACES APPEARS
POSSIBLE.  NORTHWEST WINDS WILL REMAIN GUSTY...WITH SOME GUSTS UP TO
45 MPH POSSIBLE OVER DOOR COUNTY.  DESPITE REALLY DRY AIR ARRIVING
ABOVE 850MB...ANTICIPATE CLOUDS TO STICK AROUND LONGER THAN MODELS
INDICATE DUE TO A SHARP INVERSION ON SATURDAY.  SHOULD SEE CLEARING
OCCUR THROUGH THE DAY THOUGH AS MIXING ERODES THE CLOUD COVER.   WINDS
WILL ALSO BE SUBSIDING AS WELL.  BUT TEMPS SHOULD REMAIN MAINLY IN
THE 40S.  QUIET CONDITIONS WILL PREVAIL ON SATURDAY NIGHT THANKS TO
HIGH PRESSURE...THEN WILL SEE INCREASING CLOUDS ON SUNDAY WITH A
CHANCE OF LIGHT RAIN ARRIVING SUNDAY AFTERNOON OVER N-C WISCONSIN.

REST OF THE FORECAST...THE NEXT SHORTWAVE TROUGH AND ASSOCIATED
SURFACE LOW WILL DIVE SOUTHEAST ACROSS THE REGION SUNDAY NIGHT.
BEST CHANCES OF RAIN WILL OCCUR OVER NE WISCONSIN IN THE WARM
ADVECTION ZONE...BUT THE BETTER FORCING SHOULD RESIDE NE OF THE
STATE.  WILL ADJUST POPS SLIGHTLY.  NNW FLOW WILL RESUME BEHIND THE
SYSTEM ON MONDAY WHEN THERMAL TROUGHING AND FLOW OFF LAKE SUPERIOR
SHOULD LEAD TO FAIRLY WIDESPREAD CLOUDS.  PARTIAL CLEARING SHOULD OCCUR
MONDAY NIGHT...BUT BETTER CHANCES WILL BE ON TUESDAY.  THEN LOOKS
LIKE A PERIOD OF DRY WEATHER TUESDAY THROUGH THURSDAY.
&&

.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 532 PM CDT THU OCT 16 2014

EVEN THOUGH THE TRAILING EDGE OF THE LOW CLDS FM THE SYSTEM THAT
HAS AFFECTED THE AREA SINCE LATE SUNDAY HAVE YET TO CLR THE
AREA...ANOTHER SYSTEM WL RACE IN FM THE W OVERNIGHT. MOISTURE IS
MUCH MORE LIMITED WITH THE NEW SYSTEM...BUT DYNAMICS WL BE STG AND
THAT SHOULD EVENTUALLY RESULT IN SOME PCPN. BEFORE THAT...HOWEVER...
WEAKENING PRESSURE GRADIENT BTWN THE SYSTEMS MAY ALLOW FOG AND
SOME LOW CLDS TO REFORM ACRS THE AREA TNGT. BOUNDARY LAYER WINDS
EXPECTED TO REMAIN STG ENOUGH TO KEEP THINGS FM DROPPING TOO
FAR...BUT STILL EXPECT IFR CONDITIONS TO DEVELOP AT ALL THE TAF
SITES DURING THE NGT.
&&

.MARINE...
ISSUED AT 251 PM CDT THU OCT 16 2014

WINDS WILL VEER TO THE NORTH-NORTHWEST BEHIND A COLD FRONT
FRIDAY AFTERNOON AND INCREASE QUICKLY AFTER 21Z.  AS TEMPERATURES
BECOME UNSTABLE ALOFT...SHOULD SEE EXCELLENT MOMENTUM TRANSFER OF
THE 40-45 KNOTS AT 925-900 MB TO THE SURFACE LATE FRIDAY AFTERNOON
INTO FRIDAY NIGHT.  THE CENTRAL BAY OF GREEN BAY AND LAKE MICHIGAN
NEARSHORE ADJACENT TO DOOR COUNTY WILL STAND THE GREATEST CHANCE OF
REACHING GALE CRITERIA...AND A GALE WARNING MAY BE ISSUED BY FUTURE
SHIFTS.  BECAUSE OF A LESSER OVER-WATER TRAJECTORY...THE CHANCE OF
GALE FORCE WINDS ARE LOWER OVER THE SOUTHERN BAY AND SOUTH OF THE
DOOR PENINSULA.  THE THREAT OF GALES WILL SUBSIDE LATE FRIDAY NIGHT
OR SATURDAY MORNING.
&&

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

$$

SHORT TERM.....ECKBERG
LONG TERM......MPC
AVIATION.......SKOWRONSKI
MARINE.........MPC











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