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 221936
AFDGRB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
236 PM CDT WED APR 22 2015

FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND THURSDAY
ISSUED AT 235 PM CDT WED APR 22 2015

MAIN FCST ISSUES OVER THE NEXT 24 HOURS CENTER ON PCPN TRENDS...
TIMING OF CLEARING ON THU AND TEMPS AS WE REMAIN UNSEASONABLY COOL
FOR THIS TIME OF YEAR.

THE 19Z MSAS SFC ANALYSIS INDICATED AN AREA OF LOW PRES ON THE
ONTARIO/QUEBEC BORDER WITH SEVERAL WEAK TROFS ROTATING SOUTH AND
EAST ACROSS THE GREAT LAKES. A RDG OF HI PRES WAS SITUATED FROM
THE CNTRL PLAINS NWD TO LAKE WINNIPEG. VSBL SATL IMAGERY SHOWED A
PLETHORA OF CLOUDS OVER THE GREAT LAKES WITH TEH WRN EDGE OF THESE
CLOUDS ON THE WI/MN BORDER. THE RADAR MOSAIC PAINTED SEVERAL
PATCHES OF PCPN ROTATING SEWD THRU WI THEN EWD THRU LWR MI. MOST
OF THIS PCPN WAS IN THE FORM OF LIGHT SNOW WITH THE LOWEST VSBYS
DOWNWIND OF LAKE SUPERIOR.

DIURNALLY DRIVEN RAIN/SNOW SHWRS OVER CNTRL/E-CNTRL WI TO
GRADUALLY DISSIPATE EARLY THIS EVENING WITH THE LOSS OF DAYTIME
HEATING. NRN WI TO CONT SEEING SCT SNOW SHWRS/FLURRIES THRU MUCH
OF THE NGT AS LAKE EFFECT CONDITIONS REMAIN FAVORABLE. CANNOT RULE
OUT UP TO AN ADDITIONAL INCH OF ACCUMULATION ACROSS NW PARTS OF
VILAS CNTY THIS EVENING BEFORE THE SNOW ACTIVITY SLOWLY BEGINS TO
BECOME MORE SCATTERED OVRNGT. THE CYCLONIC FLOW OVER WI DOES
SLOWLY WEAKEN TNGT...BUT STILL BE ENUF OF A FORCE TO KEEP CLOUDS
AROUND...ESPECIALLY OVER THE ERN HALF OF THE FCST AREA (OF COURSE
INCLUDING THE NORTH). MIN TEMPS WL BE TRICKY TNGT AS WINDS
DIMINISH TO UNDER 10 MPH AND EXPECT SOME BREAKS IN THE CLOUDS TO
OCCUR (ESPECIALLY OVER CNTRL WI). FOR NOW...HAVE MIN TEMPS RANGING
FROM THE LWR TO MID 20S NORTH...UPR 20S E-CNTRL WI.

IMPROVING CONDITIONS ARE EXPECTED ON THU AS THE CYCLONIC FLOW
PULLS AWAY AND THE RDG OF HI PRES PUSHES INTO THE WRN GREAT LAKES.
THE AIR MASS ALOFT IS STILL QUITE COOL BY LATE APRIL STANDARDS...
THUS EXPECT SOME FAIR WEATHER CU TO POP UP THU MORNING. ACROSS
VILAS CNTY...LINGERING LAKE EFFECT SNOW CHCS SHOULD GRADUALLY
TAPER OFF BY MIDDAY AS THE HI PRES APPROACHES. BY THU AFTERNOON...
INFLUX OF DRIER AIR SHOULD ALLOW FOR MORE SUNSHINE ACROSS NE WI
AND EVEN WITH THE COOL AIR ALOFT...MAX TEMPS ARE FCST TO REACH THE
LWR TO MID 40S NORTH...AROUND 50 DEGS E-CNTRL WI (AWAY FROM LAKE
MI).

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 235 PM CDT WED APR 22 2015

THURSDAY NIGHT THROUGH NEXT WEDNESDAY

UPPER LEVEL RIDGING WILL BE IN CONTROL OF THE WEATHER THURSDAY
NIGHT...SENDING OVERNIGHT LOWS INTO THE 20S ACROSS NORTHEAST
WISCONSIN WITH LIGHT WINDS AND MOSTLY CLEAR SKIES PROVIDING
ABUNDANT RADIATIONAL COOLING. DESPITE THE WELL BELOW NORMAL LOW
TEMPERATURES...LOWS WILL STILL BE SEVERAL DEGREES ABOVE RECORD
VALUES.

A LOW PRESSURE SYSTEM WILL ATTEMPT TO UNDERCUT THE RIDGE BY
TRACKING SOUTH THROUGH THE MISSOURI VALLEY DURING THE WEEKEND.
ALTHOUGH THERE ARE DIFFERING SOLUTIONS REGARDING THE NORTHWARD
EXTENT OF THE PRECIPITATION SHIELD ACROSS NORTHEAST
WISCONSIN...THE HUDSON BAY HIGH FEEDING DRY AIR ON NORTHEASTERLY
WINDS WILL MAKE THE TASK OF HYDRO-METEORS REACHING THE GROUND A
FAIRLY MONUMENTAL TASK. THEREFORE WILL CONTINUE WITH THE LOW 20 TO
30 PERCENT CHANCE POPS ACROSS THE SOUTHERN AND WESTERN CWA AS THE
MAIN MID LEVEL PV ANOMALY SURGES NORTHWARD FRIDAY NIGHT.

RIDGING THEN REESTABLISHES ITSELF ACROSS THE WESTERN GREAT LAKES
BEHIND THIS LOW ON SUNDAY AS AN ELONGATED TROUGH AND STRUNG OUT
SHORTWAVE TRACK THROUGH THE NORTHERN PLAINS REGION DURING THE
BEGINNING OF NEXT WEEK. THE AFOREMENTIONED RIDGE WILL KEEP THIS
TROUGH AT BAY...MAINTAINING DRY CONDITIONS THROUGH MONDAY NIGHT.
THE FORECAST BECOMES A BIT TENUOUS TUESDAY AND WEDNESDAY AS THIS
TROUGH TRACKS THROUGH THE WESTERN GREAT LAKES TUESDAY AND
WEDNESDAY. WHILE THE ECMWF BRINGS THIS TROUGH THROUGH WET...THE
GFS IS RATHER DRY DESPITE THE MID LEVEL SUPPORT. THE AMOUNT OF LOW
LEVEL DRY AIR IN PLACE IS TROUBLING WHICH WOULD SEEM TO FAVOR THE
DRY GFS SOLUTION...HOWEVER WILL MAINTAIN THE LOW CHANCY POPS AT
THIS TIME GIVEN THE UNCERTAINTY THAT FAR OUT. ON THE POSITIVE SIDE
TEMPERATURES REBOUND BACK INTO THE 50S AS 850 MB TEMPERATURES
RECOVER BACK INTO POSITIVE TERRITORY BY SUNDAY...LASTING THROUGH
NEXT WEDNESDAY. &&

.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1235 PM CDT WED APR 22 2015

PLENTY OF HI-END MVFR/LOW-END VFR CONDITIONS TO PREVAIL THIS
AFTERNOON INTO THE EVENING HOURS AS MOISTURE CONTS TO WRAP-AROUND
A LARGE...CLOSED AREA OF LOW PRES OVER E-CNTRL ONTARIO. MAINLY SCT
RAIN/SNOW SHWRS WL ALSO PERSIST INTO THE EVENING BEFORE
DIMINISHING WITH THE LOSS OF DAYTIME HEATING. EXCEPTION WOULD BE
THE RHI TAF SITE WHERE LAKE EFFECT SNOW SHWRS/FLURRIES/CLOUDS TO
PERSIST THRU MUCH OF TNGT WITH CIGS IN THE MVFR CATEGORY. A RDG OF
HI PRES IS PROGGED TO GRADUALLY PUSH INTO WI ON THU. FAIR WX CU IN
THE LOW-END VFR RANGE SHOULD DEVELOP IN THE MORNING...THEN TEND TO
DISSIPATE IN THE AFTERNOON AS THE RDG BUILDS EAST. ANTICIPATE
WIDESPREAD VFR CONDITIONS BY THU AFTERNOON.
&&

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

$$

SHORT TERM.....AK
LONG TERM......KURIMSKI
AVIATION.......AK





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