Severe Thunderstorm Warning 34, NWS Green Bay, WI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
245 PM CDT TUE JUN 29 2004

.SHORT TERM...TONIGHT AND WEDNESDAY. FORECAST FOCUS ON PRECIPITATION
CHANCES.

DEVELOPING SHOWERS AND THUNDERSTORMS WILL BE A SIGN OF THINGS TO COME
THIS EVENING AS THE FRONTAL BOUNDARY SINKS THROUGH THE CWA THIS EVENING.
MODEL INDICATED CAPES AROUND 1500 J/KG AND LI/S OF -3 TO -5 SHOULD BE
SUFFICIENT FOR SMALL HAIL WITH SOME BORDERLINE SEVERE HAIL POSSIBLE WITH
STRONGER STORMS. HOWEVER SHEAR VALUES WILL BE MARGINAL AS HELICITY
VALUES STRUGGLE TO GET ABOVE 100 SO DAMAGING WINDS ARE LESS OF A
CONCERN. THE ACTIVITY SHOULD DIE OFF SOON AFTER THE SUN GOES DOWN AS
SKIES CLEAR OUT SOME AFTER MIDNIGHT.

MOST OF WEDNESDAY WILL BE DRY AND PARTLY SUNNY AS ANOTHER FRONTAL
BOUNDARY BRINGS A CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS NORTH-
CENTRAL WISCONSIN LATE IN THE AFTERNOON. LI/S WILL BE -2 TO -4 WITH
CAPES OF 1000 TO 1500 J/KG BUT MORE IMPORTANTLY THERE WILL BE A BIT MORE
SHEAR AS HELICITY VALUES APPROACH 150 WITH MUCH STRONGER MIDDLE AND
UPPER LEVEL WINDS. IN ADDITION A STRONG 80 TO 90 KNOT JET STREAM WILL BE
PUNCHING INTO THE REGION AS WE ARE ON THE LEFT FRONT OF THE JET. THESE
DYNAMICS PUT US INTO THE SPC SLIGHT RISK FOR DAY 2 WHICH LOOKS GOOD
CONSIDERING ALL THE FACTORS. GIVEN THE STRONGER WINDS DAMAGING WINDS AND
LARGE HAIL WILL BOTH BE A THREAT. HOWEVER THE THREAT SHOULD STAY IN
NORTH-CENTRAL WISCONSIN AT LEAST DURING THE LATE AFTERNOON HOURS.

.LONG TERM...WEDS NGT THROUGH NEXT TUESDAY...MAIN CONCERN IS THE TIMING
OF THE FRONTAL BOUNDARY OVER THE HOLIDAY WEEKEND...AND ASSOC PRECIP CHCS
AND TEMPS.

MODELS ARE IN GOOD AGREEMENT IN BRINGING INITIAL CANADIAN COLD FRONT
THROUGH THE AREA WEDS NGT INTO EARLY THU. STG/SVR TSTMS ARE PSBL
OVER N WI DURING THE EVG...AS THE LFQ OF UPPER JET PUNCHES INTO THE
RGN AND LLVL MOISTURE CONVG INCREASES AHEAD OF THE FRONTAL BOUNDARY.
WILL PLACE HIGHEST POPS OVER N WI DURING THE EVG HOURS. PRECIP SHOULD
COME TO AN END ACROSS NORTHERN WI LATE WEDS NGT...AND ACROSS THE REST OF
THE AREA ON THU. HIGH PRESSURE SHOULD KEEP DRY WEATHER IN PLACE THU NGT
INTO FRI.

TIMING OF THE SECOND CANADIAN COLD FRONT IS HARDER TO PINPOINT OVER THE
WEEKEND. THE ECMWF/UKMET SUPPORT OUR CURRENT FCST...WHICH HAS THE FRONT
SHIFTING SE OF GRB CWA BY SUNDAY MORNING. THE GFS/CANADIAN SUPPORT A
SLOWER SOLN...WHICH WOULD AT LEAST KEEP A CHC OF PRECIP OVER THE FA
THROUGH SUNDAY. HOWEVER...THE GFS HAS NOT BEEN VERY CONSISTENT OVER
THE PAST FEW WEEKS...AND THE LATEST RUN HAS TRENDED FASTER AGAIN.
THEREFORE...WILL STAY WITH THE MORE PROGRESSIVE SOLN...WHICH IS FAVORED
BY HPC AND AGREES BETTER WITH THE YDAYS MODEL CONCENSUS. WILL HAVE
SMALL CHC POPS IN THE FCST FRI NGT THROUGH SAT NGT...THEN DRY SUN/MON.
ANOTHER WEAK SYSTEM APPROACHING FROM THE NORTHERN PLAINS MAY BRING A CHC
OF TSTMS TO THE RGN ON TUES.

&&

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

KURIMSKI/KIECKBUSCH
WWW.CRH.NOAA.GOV/GRB

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREEN BAY WI
1145 AM CDT TUE JUN 29 2004

WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-301645-
VILAS-ONEIDA-FOREST-FLORENCE-NORTHERN MARINETTE-SOUTHERN MARINETTE-
LINCOLN-LANGLADE-MENOMINEE-NORTHERN OCONTO-SOUTHERN OCONTO-DOOR-
MARATHON-SHAWANO-WOOD-PORTAGE-WAUPACA-OUTAGAMIE-BROWN-KEWAUNEE-WAUSHARA-
WINNEBAGO-CALUMET-MANITOWOC-
1145 AM CDT TUE JUN 29 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH-CENTRAL AND NORTHEAST
WISCONSIN.

.DAY ONE...THIS AFTERNOON AND TONIGHT

THERE IS A CHANCE OF THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. A
FRONTAL BOUNDARY WILL MOVE SOUTH OVER THE FORECAST AREA THIS AFTERNOON.
INSTABILITY AND MOISTURE MAY BE SUFFICIENT TO DEVELOP A FEW
THUNDERSTORMS ALONG OR NEAR THE FRONTAL BOUNDARY. SOME ISOLATED
THUNDERSTORMS MAY PRODUCE LARGE HAIL AND GUSTY WINDS THIS AFTERNOON AND
EVENING.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THERE IS A CHANCE OF THUNDERSTORMS WEDNESDAY AFTERNOON AND NIGHT. THERE
IS A SLIGHT RISK FOR SEVERE STORMS...MAINLY NORTH OF A LINE FROM
MARINETTE...TO NEOPIT...TO WAUSAU. SOME OF THESE STORMS MAY BE SEVERE
WITH DAMAGING WINDS AND LARGE HAIL.

THERE IS A CHANCE FOR THUNDERSTORMS THURSDAY AND SATURDAY. HOWEVER THESE
STORMS ARE NOT EXPECTED TO BE SEVERE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND TONIGHT.

KURIMSKI
WWW.CRH.NOAA.GOV/GRB