Area Forecast Discussion
Issued by NWS Green Bay, WI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KGRB 051202
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
602 AM CST FRI FEB 5 2016

UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE

.SHORT TERM...TODAY...TONIGHT...AND SATURDAY
ISSUED AT 245 AM CST FRI FEB 5 2016

A QUIET BUT PERSISTENT PATTERN FOR THE LATER HALF OF THE WORK WEEK
AND INTO THE FIRST PORTION OF THE WEEKEND. PARADE OF WEAK CLIPPER
SYSTEMS PASS OVER THE REGION DURING THE OVERNIGHT HOURS WHICH
INCLUDE THIS MORNINGS DEPARTING WEAK CLIPPER AND ANOTHER WEAK
CLIPPER FOR TONIGHT. NOT MUCH PCPN EXPECTED WITH THESE 2 SYSTEMS SO
WILL CONTINUE WITH LOWER END CHC POPS OR NON MEASURABLE FLURRIES.

THE PRIMARY CHALLENGE WILL BE CLOUD TRENDS AND AFFECTS ON
TEMPERATURES. CLEARING TREND AGAIN WILL ATTEMPT TO MOVE INTO
PARTS OF CENTRAL AND NORTH CENTRAL WISCONSIN THIS MORNING.
SIMILAR TO YESTERDAY...A FEW HOURS OF CLEARING BEFORE DAYBREAK
WILL PROVIDE ENOUGH TIME FOR CRASHING TEMPS OVER THE FRESH SNOW
COVER. ANTICIPATE SIMILAR CONDITIONS THIS MORNING AND AGAIN LATE
TONIGHT. AS FAR AS DAYTIME HIGHS...PLENTY OF SUNSHINE ON THURSDAY
PRODUCE TEMPS FROM THE LOWER 20S NORTH TO UPPER 20S CENTRAL AND
EAST CENTRAL...AND EXPECT SIMILAR RESULTS TODAY AND PERHAPS EVEN
FOR SATURDAY.

WINDS APPEAR TOO WESTERLY THROUGH SATURDAY FOR LAKE EFFECT
MENTION FAR NORTH.

.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY
ISSUED AT 245 AM CST FRI FEB 5 2016

LONG-RANGE MODEL GUIDANCE REMAINS IN GOOD AGREEMENT WITH THE
DEVELOPMENT OF A HIGHLY-AMPLIFIED MEAN FLOW CONSISTING OF A WRN
NOAM UPR RDG AND E-CNTRL NOAM UPR TROF THRU THE MIDDLE OF NEXT
WEEK BEFORE THE UPR RDG WEAKENS A BIT LATE NEXT WEEK. MAIN FCST
FOCUS TO BE ON THE THIRD IN A SERIES OF CLIPPER SYSTEMS THAT IS
FCST TO IMPACT THE GREAT LAKES DURING THE SUNDAY INTO MON NGT TIME
FRAME. TEMPS TO BE ABOVE NORMAL THRU MON...THEN FALL TO BELOW
NORMAL LEVELS FOR TUE THRU THU.

MODELS ARE IN FAIR AGREEMENT IN TAKING THIS CLIPPER E-SE TOWARD SE
MANITOBA OR NW MN BY 12Z SUNDAY. SW WINDS IN ADVANCE OF THE
CLIPPER WL INCREASE ISEN LIFT OVER WI AND PERHAPS BRING A CHC OF
LIGHT SNOW ACROSS NRN WI IN THE VCNTY OF A STALLED FRONTAL
BOUNDARY. DO NOT BUY THE GEM THAT RACES PCPN THRU MOST OF THE FCST
AREA SAT NGT AS IT WL TAKE SOME TIME TO SATURATE THE ATMOSPHERE.
PREFER TO JUST THICKEN UP THE CLOUDS BUT KEEP CNTRL/E-CNTRL WI DRY
THRU THE NGT. MILD CONDITIONS ARE EXPECTED WITH MIN TEMPS IN THE
LWR 20 NORTH...MID 20S SOUTH. THERE ARE STILL ISSUES AMONG THE
MODELS WITH RESPECT TO THE TRACK AND INTENSITY OF THE SFC LOW
HEADED INTO SUNDAY WITH THE NAM/GFS TAKING A MORE SE TRACK
COMPARED TO A E-SE TRACK ON THE GEM/ECMWF. THIS DIFFERENCE MAY NOT
MATTER AS A CDFNT IS FCST TO PUSH THRU MOST OF WI AND PROVIDE ENUF
LIFT TO BRING A CHC OF LIGHT SNOW TO MUCH OF THE REGION. TEMPS
OVER FAR SRN SECTIONS OF THE FCST AREA MAY WARM UP JUST ENUF TO
HAVE A LITTLE RAIN MIX WITH THE SNOW. THE MILD CONDITIONS WOULD
LIMIT ACCUMULATION POTENTIAL WITH NRN WI RECEIVING NEAR ONE
INCH...WHILE SRN SECTIONS ONLY GET A FEW TENTHS OF AN INCH.

THE CLIPPER IS PROGGED TO SLOWLY MOVE ACROSS THE GREAT LAKES
SUNDAY NGT INTO MON...WHILE THE UPR TROF DEEPENS OVER E-CNTRL
NOAM. THE COMBINATION OF CYCLONIC FLOW AND VARIOUS PIECES OF
SHORTWAVE ENERGY DROPPING SE WITHIN THE UPR TROF WL CONT TO BRING
SNOW CHCS TO NE WI. MOST OF THE SNOW APPEARS TO BE OF THE LIGHT
VARIETY WITH MOST LOCATIONS SEEING AN INCH OR LESS OF SNOW SUNDAY
NGT AND UNDER AN INCH ON MON. AN EXCEPTION WOULD BE N-CNTRL WI
WHERE THE WINDS WL BECOME NORTHERLY AND AS COLDER AIR ADVECTS INTO
THE REGION...LEAD TO LAKE ENHANCEMENT FROM SUPERIOR. ANOTHER THING
TO WATCH ON MON WL BE THE TIGHTENING PRESSURE GRADIENT WHICH WOULD
ALLOW BLOWING AND DRIFTING SNOW TO OCCUR. ONSET OF CAA WL ONLY
ALLOW MAX TEMPS TO REACH THE MID TO UPR 20S CNTRL WI...UPR 20S TO
LWR 30S DESPITE ANOTHER MILD START TO THE DAY.

THIS PESKY SYSTEM IS EXPECTED TO LINGER OVER THE GREAT LAKES ALL
THE WAY INTO TUE BEFORE FINALLY SHIFTING FAR ENUF TO THE EAST TO
ALLOW THE SNOW CHCS TO DIMINISH. MAIN CONCERN FOR MON NGT/TUE WL
BE THE LAKE EFFECT SNOW THREAT FOR N-CNTRL WI AS TRAJS ARE
FAVORABLE...DELTA-T VALUES RISE INTO THE LWR TO MID 20S AND THE
FLOW REMAINS CYCLONIC. HAVE RAISED POPS OVER PARTS OF VILAS CNTY
INTO THE LIKELY CATEGORY FOR NOW. A NOTICEABLE AIR MASS CHANGE WL
BE FELT ON TUE WITH MAX TEMPS ONLY IN THE TEENS NRN/CNTRL WI...
AROUND 20 DEGS E-CNTRL WI. ADD IN GUSTY N-NW WINDS AND WIND CHILLS
WL BE IN THE SINGLE DIGITS TO LWR TEENS ABOVE ZERO.

THE LAKE EFFECT SNOW SHWR CHCS LOOK TO PERSIST INTO WED AS THE
REGION IS LOCKED UNDER A COLD NW FLOW ALOFT. A RDG OF HI PRES IS
FCST TO BUILD ACROSS THE PLAINS INTO THE UPR MIDWEST BY WED AND
MAY ALLOW SKIES TO AT LEAST BECOME PARTLY CLOUDY TUE NGT THRU WED
AWAY FROM N-CNTRL WI. IF SOME CLEARING CAN OCCUR...TEMPS TUE NGT
COULD FALL BELOW ZERO OVER PARTS OF CNTRL/N-CNTRL WI. MAX TEMPS ON
WED ARE EXPECTED TO BE ABOUT 10 DEGS BELOW NORMAL.

CLOUDS LOOK TO BE ON THE INCREASE NEXT THU AS THERE ARE SIGNS OF
YET ANOTHER CLIPPER SYSTEM TO BE HEADED TOWARD THE GREAT LAKES. A
RETURN TO SOUTHERLY WINDS AHEAD OF THIS CLIPPER SHOULD SEND MAX
TEMPS THU TO AROUND 20 DEGS NORTH...LWR 20S SOUTH.
&&

.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 602 AM CST FRI FEB 5 2016

PATCHY MVFR CONDITIONS WILL LINGER TO AROUND 14Z TODAY
OTHERWISE VFR CONDITIONS EXPECTED TODAY. MID LEVEL CLOUDS WILL BE
ON THE INCREASE FROM WEST TO EAST THIS AFTERNOON AND EVENING AS
ANOTHER WEAK CLIPPER SYSTEM APPROACHES. SCATTERED MVFR VSBYS DUE
TO SNOW WITH MVFR CIGS MAY DEVELOP TONIGHT AS THE SYSTEM TRACKS
OVER THE AREA.
&&

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

$$

SHORT TERM.....TDH
LONG TERM......AK
AVIATION.......TDH


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.